xref: /petsc/src/mat/impls/aij/mpi/mpiaij.c (revision 22559b1cf89f622cefbe79358df6c7a899186386)
1 
2 #include <../src/mat/impls/aij/mpi/mpiaij.h>   /*I "petscmat.h" I*/
3 #include <petsc-private/vecimpl.h>
4 #include <petscblaslapack.h>
5 #include <petscsf.h>
6 
7 /*MC
8    MATAIJ - MATAIJ = "aij" - A matrix type to be used for sparse matrices.
9 
10    This matrix type is identical to MATSEQAIJ when constructed with a single process communicator,
11    and MATMPIAIJ otherwise.  As a result, for single process communicators,
12   MatSeqAIJSetPreallocation is supported, and similarly MatMPIAIJSetPreallocation is supported
13   for communicators controlling multiple processes.  It is recommended that you call both of
14   the above preallocation routines for simplicity.
15 
16    Options Database Keys:
17 . -mat_type aij - sets the matrix type to "aij" during a call to MatSetFromOptions()
18 
19   Developer Notes: Subclasses include MATAIJCUSP, MATAIJCUSPARSE, MATAIJPERM, MATAIJCRL, and also automatically switches over to use inodes when
20    enough exist.
21 
22   Level: beginner
23 
24 .seealso: MatCreateAIJ(), MatCreateSeqAIJ(), MATSEQAIJ,MATMPIAIJ
25 M*/
26 
27 /*MC
28    MATAIJCRL - MATAIJCRL = "aijcrl" - A matrix type to be used for sparse matrices.
29 
30    This matrix type is identical to MATSEQAIJCRL when constructed with a single process communicator,
31    and MATMPIAIJCRL otherwise.  As a result, for single process communicators,
32    MatSeqAIJSetPreallocation() is supported, and similarly MatMPIAIJSetPreallocation() is supported
33   for communicators controlling multiple processes.  It is recommended that you call both of
34   the above preallocation routines for simplicity.
35 
36    Options Database Keys:
37 . -mat_type aijcrl - sets the matrix type to "aijcrl" during a call to MatSetFromOptions()
38 
39   Level: beginner
40 
41 .seealso: MatCreateMPIAIJCRL,MATSEQAIJCRL,MATMPIAIJCRL, MATSEQAIJCRL, MATMPIAIJCRL
42 M*/
43 
44 #undef __FUNCT__
45 #define __FUNCT__ "MatFindNonzeroRows_MPIAIJ"
46 PetscErrorCode MatFindNonzeroRows_MPIAIJ(Mat M,IS *keptrows)
47 {
48   PetscErrorCode  ierr;
49   Mat_MPIAIJ      *mat = (Mat_MPIAIJ*)M->data;
50   Mat_SeqAIJ      *a   = (Mat_SeqAIJ*)mat->A->data;
51   Mat_SeqAIJ      *b   = (Mat_SeqAIJ*)mat->B->data;
52   const PetscInt  *ia,*ib;
53   const MatScalar *aa,*bb;
54   PetscInt        na,nb,i,j,*rows,cnt=0,n0rows;
55   PetscInt        m = M->rmap->n,rstart = M->rmap->rstart;
56 
57   PetscFunctionBegin;
58   *keptrows = 0;
59   ia        = a->i;
60   ib        = b->i;
61   for (i=0; i<m; i++) {
62     na = ia[i+1] - ia[i];
63     nb = ib[i+1] - ib[i];
64     if (!na && !nb) {
65       cnt++;
66       goto ok1;
67     }
68     aa = a->a + ia[i];
69     for (j=0; j<na; j++) {
70       if (aa[j] != 0.0) goto ok1;
71     }
72     bb = b->a + ib[i];
73     for (j=0; j <nb; j++) {
74       if (bb[j] != 0.0) goto ok1;
75     }
76     cnt++;
77 ok1:;
78   }
79   ierr = MPI_Allreduce(&cnt,&n0rows,1,MPIU_INT,MPI_SUM,PetscObjectComm((PetscObject)M));CHKERRQ(ierr);
80   if (!n0rows) PetscFunctionReturn(0);
81   ierr = PetscMalloc((M->rmap->n-cnt)*sizeof(PetscInt),&rows);CHKERRQ(ierr);
82   cnt  = 0;
83   for (i=0; i<m; i++) {
84     na = ia[i+1] - ia[i];
85     nb = ib[i+1] - ib[i];
86     if (!na && !nb) continue;
87     aa = a->a + ia[i];
88     for (j=0; j<na;j++) {
89       if (aa[j] != 0.0) {
90         rows[cnt++] = rstart + i;
91         goto ok2;
92       }
93     }
94     bb = b->a + ib[i];
95     for (j=0; j<nb; j++) {
96       if (bb[j] != 0.0) {
97         rows[cnt++] = rstart + i;
98         goto ok2;
99       }
100     }
101 ok2:;
102   }
103   ierr = ISCreateGeneral(PetscObjectComm((PetscObject)M),cnt,rows,PETSC_OWN_POINTER,keptrows);CHKERRQ(ierr);
104   PetscFunctionReturn(0);
105 }
106 
107 #undef __FUNCT__
108 #define __FUNCT__ "MatFindZeroDiagonals_MPIAIJ"
109 PetscErrorCode MatFindZeroDiagonals_MPIAIJ(Mat M,IS *zrows)
110 {
111   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)M->data;
112   PetscErrorCode ierr;
113   PetscInt       i,rstart,nrows,*rows;
114 
115   PetscFunctionBegin;
116   *zrows = NULL;
117   ierr   = MatFindZeroDiagonals_SeqAIJ_Private(aij->A,&nrows,&rows);CHKERRQ(ierr);
118   ierr   = MatGetOwnershipRange(M,&rstart,NULL);CHKERRQ(ierr);
119   for (i=0; i<nrows; i++) rows[i] += rstart;
120   ierr = ISCreateGeneral(PetscObjectComm((PetscObject)M),nrows,rows,PETSC_OWN_POINTER,zrows);CHKERRQ(ierr);
121   PetscFunctionReturn(0);
122 }
123 
124 #undef __FUNCT__
125 #define __FUNCT__ "MatGetColumnNorms_MPIAIJ"
126 PetscErrorCode MatGetColumnNorms_MPIAIJ(Mat A,NormType type,PetscReal *norms)
127 {
128   PetscErrorCode ierr;
129   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)A->data;
130   PetscInt       i,n,*garray = aij->garray;
131   Mat_SeqAIJ     *a_aij = (Mat_SeqAIJ*) aij->A->data;
132   Mat_SeqAIJ     *b_aij = (Mat_SeqAIJ*) aij->B->data;
133   PetscReal      *work;
134 
135   PetscFunctionBegin;
136   ierr = MatGetSize(A,NULL,&n);CHKERRQ(ierr);
137   ierr = PetscMalloc(n*sizeof(PetscReal),&work);CHKERRQ(ierr);
138   ierr = PetscMemzero(work,n*sizeof(PetscReal));CHKERRQ(ierr);
139   if (type == NORM_2) {
140     for (i=0; i<a_aij->i[aij->A->rmap->n]; i++) {
141       work[A->cmap->rstart + a_aij->j[i]] += PetscAbsScalar(a_aij->a[i]*a_aij->a[i]);
142     }
143     for (i=0; i<b_aij->i[aij->B->rmap->n]; i++) {
144       work[garray[b_aij->j[i]]] += PetscAbsScalar(b_aij->a[i]*b_aij->a[i]);
145     }
146   } else if (type == NORM_1) {
147     for (i=0; i<a_aij->i[aij->A->rmap->n]; i++) {
148       work[A->cmap->rstart + a_aij->j[i]] += PetscAbsScalar(a_aij->a[i]);
149     }
150     for (i=0; i<b_aij->i[aij->B->rmap->n]; i++) {
151       work[garray[b_aij->j[i]]] += PetscAbsScalar(b_aij->a[i]);
152     }
153   } else if (type == NORM_INFINITY) {
154     for (i=0; i<a_aij->i[aij->A->rmap->n]; i++) {
155       work[A->cmap->rstart + a_aij->j[i]] = PetscMax(PetscAbsScalar(a_aij->a[i]), work[A->cmap->rstart + a_aij->j[i]]);
156     }
157     for (i=0; i<b_aij->i[aij->B->rmap->n]; i++) {
158       work[garray[b_aij->j[i]]] = PetscMax(PetscAbsScalar(b_aij->a[i]),work[garray[b_aij->j[i]]]);
159     }
160 
161   } else SETERRQ(PetscObjectComm((PetscObject)A),PETSC_ERR_ARG_WRONG,"Unknown NormType");
162   if (type == NORM_INFINITY) {
163     ierr = MPI_Allreduce(work,norms,n,MPIU_REAL,MPIU_MAX,A->hdr.comm);CHKERRQ(ierr);
164   } else {
165     ierr = MPI_Allreduce(work,norms,n,MPIU_REAL,MPIU_SUM,A->hdr.comm);CHKERRQ(ierr);
166   }
167   ierr = PetscFree(work);CHKERRQ(ierr);
168   if (type == NORM_2) {
169     for (i=0; i<n; i++) norms[i] = PetscSqrtReal(norms[i]);
170   }
171   PetscFunctionReturn(0);
172 }
173 
174 #undef __FUNCT__
175 #define __FUNCT__ "MatDistribute_MPIAIJ"
176 /*
177     Distributes a SeqAIJ matrix across a set of processes. Code stolen from
178     MatLoad_MPIAIJ(). Horrible lack of reuse. Should be a routine for each matrix type.
179 
180     Only for square matrices
181 
182     Used by a preconditioner, hence PETSC_EXTERN
183 */
184 PETSC_EXTERN PetscErrorCode MatDistribute_MPIAIJ(MPI_Comm comm,Mat gmat,PetscInt m,MatReuse reuse,Mat *inmat)
185 {
186   PetscMPIInt    rank,size;
187   PetscInt       *rowners,*dlens,*olens,i,rstart,rend,j,jj,nz,*gmataj,cnt,row,*ld,bses[2];
188   PetscErrorCode ierr;
189   Mat            mat;
190   Mat_SeqAIJ     *gmata;
191   PetscMPIInt    tag;
192   MPI_Status     status;
193   PetscBool      aij;
194   MatScalar      *gmataa,*ao,*ad,*gmataarestore=0;
195 
196   PetscFunctionBegin;
197   ierr = MPI_Comm_rank(comm,&rank);CHKERRQ(ierr);
198   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
199   if (!rank) {
200     ierr = PetscObjectTypeCompare((PetscObject)gmat,MATSEQAIJ,&aij);CHKERRQ(ierr);
201     if (!aij) SETERRQ1(PetscObjectComm((PetscObject)gmat),PETSC_ERR_SUP,"Currently no support for input matrix of type %s\n",((PetscObject)gmat)->type_name);
202   }
203   if (reuse == MAT_INITIAL_MATRIX) {
204     ierr = MatCreate(comm,&mat);CHKERRQ(ierr);
205     ierr = MatSetSizes(mat,m,m,PETSC_DETERMINE,PETSC_DETERMINE);CHKERRQ(ierr);
206     if (!rank) {
207       bses[0] = gmat->rmap->bs;
208       bses[1] = gmat->cmap->bs;
209     }
210     ierr = MPI_Bcast(bses,2,MPIU_INT,0,comm);CHKERRQ(ierr);
211     ierr = MatSetBlockSizes(mat,bses[0],bses[1]);CHKERRQ(ierr);
212     ierr = MatSetType(mat,MATAIJ);CHKERRQ(ierr);
213     ierr = PetscMalloc((size+1)*sizeof(PetscInt),&rowners);CHKERRQ(ierr);
214     ierr = PetscMalloc2(m,PetscInt,&dlens,m,PetscInt,&olens);CHKERRQ(ierr);
215     ierr = MPI_Allgather(&m,1,MPIU_INT,rowners+1,1,MPIU_INT,comm);CHKERRQ(ierr);
216 
217     rowners[0] = 0;
218     for (i=2; i<=size; i++) rowners[i] += rowners[i-1];
219     rstart = rowners[rank];
220     rend   = rowners[rank+1];
221     ierr   = PetscObjectGetNewTag((PetscObject)mat,&tag);CHKERRQ(ierr);
222     if (!rank) {
223       gmata = (Mat_SeqAIJ*) gmat->data;
224       /* send row lengths to all processors */
225       for (i=0; i<m; i++) dlens[i] = gmata->ilen[i];
226       for (i=1; i<size; i++) {
227         ierr = MPI_Send(gmata->ilen + rowners[i],rowners[i+1]-rowners[i],MPIU_INT,i,tag,comm);CHKERRQ(ierr);
228       }
229       /* determine number diagonal and off-diagonal counts */
230       ierr = PetscMemzero(olens,m*sizeof(PetscInt));CHKERRQ(ierr);
231       ierr = PetscMalloc(m*sizeof(PetscInt),&ld);CHKERRQ(ierr);
232       ierr = PetscMemzero(ld,m*sizeof(PetscInt));CHKERRQ(ierr);
233       jj   = 0;
234       for (i=0; i<m; i++) {
235         for (j=0; j<dlens[i]; j++) {
236           if (gmata->j[jj] < rstart) ld[i]++;
237           if (gmata->j[jj] < rstart || gmata->j[jj] >= rend) olens[i]++;
238           jj++;
239         }
240       }
241       /* send column indices to other processes */
242       for (i=1; i<size; i++) {
243         nz   = gmata->i[rowners[i+1]]-gmata->i[rowners[i]];
244         ierr = MPI_Send(&nz,1,MPIU_INT,i,tag,comm);CHKERRQ(ierr);
245         ierr = MPI_Send(gmata->j + gmata->i[rowners[i]],nz,MPIU_INT,i,tag,comm);CHKERRQ(ierr);
246       }
247 
248       /* send numerical values to other processes */
249       for (i=1; i<size; i++) {
250         nz   = gmata->i[rowners[i+1]]-gmata->i[rowners[i]];
251         ierr = MPI_Send(gmata->a + gmata->i[rowners[i]],nz,MPIU_SCALAR,i,tag,comm);CHKERRQ(ierr);
252       }
253       gmataa = gmata->a;
254       gmataj = gmata->j;
255 
256     } else {
257       /* receive row lengths */
258       ierr = MPI_Recv(dlens,m,MPIU_INT,0,tag,comm,&status);CHKERRQ(ierr);
259       /* receive column indices */
260       ierr = MPI_Recv(&nz,1,MPIU_INT,0,tag,comm,&status);CHKERRQ(ierr);
261       ierr = PetscMalloc2(nz,PetscScalar,&gmataa,nz,PetscInt,&gmataj);CHKERRQ(ierr);
262       ierr = MPI_Recv(gmataj,nz,MPIU_INT,0,tag,comm,&status);CHKERRQ(ierr);
263       /* determine number diagonal and off-diagonal counts */
264       ierr = PetscMemzero(olens,m*sizeof(PetscInt));CHKERRQ(ierr);
265       ierr = PetscMalloc(m*sizeof(PetscInt),&ld);CHKERRQ(ierr);
266       ierr = PetscMemzero(ld,m*sizeof(PetscInt));CHKERRQ(ierr);
267       jj   = 0;
268       for (i=0; i<m; i++) {
269         for (j=0; j<dlens[i]; j++) {
270           if (gmataj[jj] < rstart) ld[i]++;
271           if (gmataj[jj] < rstart || gmataj[jj] >= rend) olens[i]++;
272           jj++;
273         }
274       }
275       /* receive numerical values */
276       ierr = PetscMemzero(gmataa,nz*sizeof(PetscScalar));CHKERRQ(ierr);
277       ierr = MPI_Recv(gmataa,nz,MPIU_SCALAR,0,tag,comm,&status);CHKERRQ(ierr);
278     }
279     /* set preallocation */
280     for (i=0; i<m; i++) {
281       dlens[i] -= olens[i];
282     }
283     ierr = MatSeqAIJSetPreallocation(mat,0,dlens);CHKERRQ(ierr);
284     ierr = MatMPIAIJSetPreallocation(mat,0,dlens,0,olens);CHKERRQ(ierr);
285 
286     for (i=0; i<m; i++) {
287       dlens[i] += olens[i];
288     }
289     cnt = 0;
290     for (i=0; i<m; i++) {
291       row  = rstart + i;
292       ierr = MatSetValues(mat,1,&row,dlens[i],gmataj+cnt,gmataa+cnt,INSERT_VALUES);CHKERRQ(ierr);
293       cnt += dlens[i];
294     }
295     if (rank) {
296       ierr = PetscFree2(gmataa,gmataj);CHKERRQ(ierr);
297     }
298     ierr = PetscFree2(dlens,olens);CHKERRQ(ierr);
299     ierr = PetscFree(rowners);CHKERRQ(ierr);
300 
301     ((Mat_MPIAIJ*)(mat->data))->ld = ld;
302 
303     *inmat = mat;
304   } else {   /* column indices are already set; only need to move over numerical values from process 0 */
305     Mat_SeqAIJ *Ad = (Mat_SeqAIJ*)((Mat_MPIAIJ*)((*inmat)->data))->A->data;
306     Mat_SeqAIJ *Ao = (Mat_SeqAIJ*)((Mat_MPIAIJ*)((*inmat)->data))->B->data;
307     mat  = *inmat;
308     ierr = PetscObjectGetNewTag((PetscObject)mat,&tag);CHKERRQ(ierr);
309     if (!rank) {
310       /* send numerical values to other processes */
311       gmata  = (Mat_SeqAIJ*) gmat->data;
312       ierr   = MatGetOwnershipRanges(mat,(const PetscInt**)&rowners);CHKERRQ(ierr);
313       gmataa = gmata->a;
314       for (i=1; i<size; i++) {
315         nz   = gmata->i[rowners[i+1]]-gmata->i[rowners[i]];
316         ierr = MPI_Send(gmataa + gmata->i[rowners[i]],nz,MPIU_SCALAR,i,tag,comm);CHKERRQ(ierr);
317       }
318       nz = gmata->i[rowners[1]]-gmata->i[rowners[0]];
319     } else {
320       /* receive numerical values from process 0*/
321       nz   = Ad->nz + Ao->nz;
322       ierr = PetscMalloc(nz*sizeof(PetscScalar),&gmataa);CHKERRQ(ierr); gmataarestore = gmataa;
323       ierr = MPI_Recv(gmataa,nz,MPIU_SCALAR,0,tag,comm,&status);CHKERRQ(ierr);
324     }
325     /* transfer numerical values into the diagonal A and off diagonal B parts of mat */
326     ld = ((Mat_MPIAIJ*)(mat->data))->ld;
327     ad = Ad->a;
328     ao = Ao->a;
329     if (mat->rmap->n) {
330       i  = 0;
331       nz = ld[i];                                   ierr = PetscMemcpy(ao,gmataa,nz*sizeof(PetscScalar));CHKERRQ(ierr); ao += nz; gmataa += nz;
332       nz = Ad->i[i+1] - Ad->i[i];                   ierr = PetscMemcpy(ad,gmataa,nz*sizeof(PetscScalar));CHKERRQ(ierr); ad += nz; gmataa += nz;
333     }
334     for (i=1; i<mat->rmap->n; i++) {
335       nz = Ao->i[i] - Ao->i[i-1] - ld[i-1] + ld[i]; ierr = PetscMemcpy(ao,gmataa,nz*sizeof(PetscScalar));CHKERRQ(ierr); ao += nz; gmataa += nz;
336       nz = Ad->i[i+1] - Ad->i[i];                   ierr = PetscMemcpy(ad,gmataa,nz*sizeof(PetscScalar));CHKERRQ(ierr); ad += nz; gmataa += nz;
337     }
338     i--;
339     if (mat->rmap->n) {
340       nz = Ao->i[i+1] - Ao->i[i] - ld[i];           ierr = PetscMemcpy(ao,gmataa,nz*sizeof(PetscScalar));CHKERRQ(ierr);
341     }
342     if (rank) {
343       ierr = PetscFree(gmataarestore);CHKERRQ(ierr);
344     }
345   }
346   ierr = MatAssemblyBegin(mat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
347   ierr = MatAssemblyEnd(mat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
348   PetscFunctionReturn(0);
349 }
350 
351 /*
352   Local utility routine that creates a mapping from the global column
353 number to the local number in the off-diagonal part of the local
354 storage of the matrix.  When PETSC_USE_CTABLE is used this is scalable at
355 a slightly higher hash table cost; without it it is not scalable (each processor
356 has an order N integer array but is fast to acess.
357 */
358 #undef __FUNCT__
359 #define __FUNCT__ "MatCreateColmap_MPIAIJ_Private"
360 PetscErrorCode MatCreateColmap_MPIAIJ_Private(Mat mat)
361 {
362   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
363   PetscErrorCode ierr;
364   PetscInt       n = aij->B->cmap->n,i;
365 
366   PetscFunctionBegin;
367   if (!aij->garray) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_PLIB,"MPIAIJ Matrix was assembled but is missing garray");
368 #if defined(PETSC_USE_CTABLE)
369   ierr = PetscTableCreate(n,mat->cmap->N+1,&aij->colmap);CHKERRQ(ierr);
370   for (i=0; i<n; i++) {
371     ierr = PetscTableAdd(aij->colmap,aij->garray[i]+1,i+1,INSERT_VALUES);CHKERRQ(ierr);
372   }
373 #else
374   ierr = PetscMalloc((mat->cmap->N+1)*sizeof(PetscInt),&aij->colmap);CHKERRQ(ierr);
375   ierr = PetscLogObjectMemory(mat,mat->cmap->N*sizeof(PetscInt));CHKERRQ(ierr);
376   ierr = PetscMemzero(aij->colmap,mat->cmap->N*sizeof(PetscInt));CHKERRQ(ierr);
377   for (i=0; i<n; i++) aij->colmap[aij->garray[i]] = i+1;
378 #endif
379   PetscFunctionReturn(0);
380 }
381 
382 #define MatSetValues_SeqAIJ_A_Private(row,col,value,addv) \
383 { \
384     if (col <= lastcol1)  low1 = 0;     \
385     else                 high1 = nrow1; \
386     lastcol1 = col;\
387     while (high1-low1 > 5) { \
388       t = (low1+high1)/2; \
389       if (rp1[t] > col) high1 = t; \
390       else              low1  = t; \
391     } \
392       for (_i=low1; _i<high1; _i++) { \
393         if (rp1[_i] > col) break; \
394         if (rp1[_i] == col) { \
395           if (addv == ADD_VALUES) ap1[_i] += value;   \
396           else                    ap1[_i] = value; \
397           goto a_noinsert; \
398         } \
399       }  \
400       if (value == 0.0 && ignorezeroentries) {low1 = 0; high1 = nrow1;goto a_noinsert;} \
401       if (nonew == 1) {low1 = 0; high1 = nrow1; goto a_noinsert;}                \
402       if (nonew == -1) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Inserting a new nonzero (%D, %D) into matrix", row, col); \
403       MatSeqXAIJReallocateAIJ(A,am,1,nrow1,row,col,rmax1,aa,ai,aj,rp1,ap1,aimax,nonew,MatScalar); \
404       N = nrow1++ - 1; a->nz++; high1++; \
405       /* shift up all the later entries in this row */ \
406       for (ii=N; ii>=_i; ii--) { \
407         rp1[ii+1] = rp1[ii]; \
408         ap1[ii+1] = ap1[ii]; \
409       } \
410       rp1[_i] = col;  \
411       ap1[_i] = value;  \
412       a_noinsert: ; \
413       ailen[row] = nrow1; \
414 }
415 
416 
417 #define MatSetValues_SeqAIJ_B_Private(row,col,value,addv) \
418   { \
419     if (col <= lastcol2) low2 = 0;                        \
420     else high2 = nrow2;                                   \
421     lastcol2 = col;                                       \
422     while (high2-low2 > 5) {                              \
423       t = (low2+high2)/2;                                 \
424       if (rp2[t] > col) high2 = t;                        \
425       else             low2  = t;                         \
426     }                                                     \
427     for (_i=low2; _i<high2; _i++) {                       \
428       if (rp2[_i] > col) break;                           \
429       if (rp2[_i] == col) {                               \
430         if (addv == ADD_VALUES) ap2[_i] += value;         \
431         else                    ap2[_i] = value;          \
432         goto b_noinsert;                                  \
433       }                                                   \
434     }                                                     \
435     if (value == 0.0 && ignorezeroentries) {low2 = 0; high2 = nrow2; goto b_noinsert;} \
436     if (nonew == 1) {low2 = 0; high2 = nrow2; goto b_noinsert;}                        \
437     if (nonew == -1) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Inserting a new nonzero (%D, %D) into matrix", row, col); \
438     MatSeqXAIJReallocateAIJ(B,bm,1,nrow2,row,col,rmax2,ba,bi,bj,rp2,ap2,bimax,nonew,MatScalar); \
439     N = nrow2++ - 1; b->nz++; high2++;                    \
440     /* shift up all the later entries in this row */      \
441     for (ii=N; ii>=_i; ii--) {                            \
442       rp2[ii+1] = rp2[ii];                                \
443       ap2[ii+1] = ap2[ii];                                \
444     }                                                     \
445     rp2[_i] = col;                                        \
446     ap2[_i] = value;                                      \
447     b_noinsert: ;                                         \
448     bilen[row] = nrow2;                                   \
449   }
450 
451 #undef __FUNCT__
452 #define __FUNCT__ "MatSetValuesRow_MPIAIJ"
453 PetscErrorCode MatSetValuesRow_MPIAIJ(Mat A,PetscInt row,const PetscScalar v[])
454 {
455   Mat_MPIAIJ     *mat = (Mat_MPIAIJ*)A->data;
456   Mat_SeqAIJ     *a   = (Mat_SeqAIJ*)mat->A->data,*b = (Mat_SeqAIJ*)mat->B->data;
457   PetscErrorCode ierr;
458   PetscInt       l,*garray = mat->garray,diag;
459 
460   PetscFunctionBegin;
461   /* code only works for square matrices A */
462 
463   /* find size of row to the left of the diagonal part */
464   ierr = MatGetOwnershipRange(A,&diag,0);CHKERRQ(ierr);
465   row  = row - diag;
466   for (l=0; l<b->i[row+1]-b->i[row]; l++) {
467     if (garray[b->j[b->i[row]+l]] > diag) break;
468   }
469   ierr = PetscMemcpy(b->a+b->i[row],v,l*sizeof(PetscScalar));CHKERRQ(ierr);
470 
471   /* diagonal part */
472   ierr = PetscMemcpy(a->a+a->i[row],v+l,(a->i[row+1]-a->i[row])*sizeof(PetscScalar));CHKERRQ(ierr);
473 
474   /* right of diagonal part */
475   ierr = PetscMemcpy(b->a+b->i[row]+l,v+l+a->i[row+1]-a->i[row],(b->i[row+1]-b->i[row]-l)*sizeof(PetscScalar));CHKERRQ(ierr);
476   PetscFunctionReturn(0);
477 }
478 
479 #undef __FUNCT__
480 #define __FUNCT__ "MatSetValues_MPIAIJ"
481 PetscErrorCode MatSetValues_MPIAIJ(Mat mat,PetscInt m,const PetscInt im[],PetscInt n,const PetscInt in[],const PetscScalar v[],InsertMode addv)
482 {
483   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
484   PetscScalar    value;
485   PetscErrorCode ierr;
486   PetscInt       i,j,rstart  = mat->rmap->rstart,rend = mat->rmap->rend;
487   PetscInt       cstart      = mat->cmap->rstart,cend = mat->cmap->rend,row,col;
488   PetscBool      roworiented = aij->roworiented;
489 
490   /* Some Variables required in the macro */
491   Mat        A                 = aij->A;
492   Mat_SeqAIJ *a                = (Mat_SeqAIJ*)A->data;
493   PetscInt   *aimax            = a->imax,*ai = a->i,*ailen = a->ilen,*aj = a->j;
494   MatScalar  *aa               = a->a;
495   PetscBool  ignorezeroentries = a->ignorezeroentries;
496   Mat        B                 = aij->B;
497   Mat_SeqAIJ *b                = (Mat_SeqAIJ*)B->data;
498   PetscInt   *bimax            = b->imax,*bi = b->i,*bilen = b->ilen,*bj = b->j,bm = aij->B->rmap->n,am = aij->A->rmap->n;
499   MatScalar  *ba               = b->a;
500 
501   PetscInt  *rp1,*rp2,ii,nrow1,nrow2,_i,rmax1,rmax2,N,low1,high1,low2,high2,t,lastcol1,lastcol2;
502   PetscInt  nonew;
503   MatScalar *ap1,*ap2;
504 
505   PetscFunctionBegin;
506   if (v) PetscValidScalarPointer(v,6);
507   for (i=0; i<m; i++) {
508     if (im[i] < 0) continue;
509 #if defined(PETSC_USE_DEBUG)
510     if (im[i] >= mat->rmap->N) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Row too large: row %D max %D",im[i],mat->rmap->N-1);
511 #endif
512     if (im[i] >= rstart && im[i] < rend) {
513       row      = im[i] - rstart;
514       lastcol1 = -1;
515       rp1      = aj + ai[row];
516       ap1      = aa + ai[row];
517       rmax1    = aimax[row];
518       nrow1    = ailen[row];
519       low1     = 0;
520       high1    = nrow1;
521       lastcol2 = -1;
522       rp2      = bj + bi[row];
523       ap2      = ba + bi[row];
524       rmax2    = bimax[row];
525       nrow2    = bilen[row];
526       low2     = 0;
527       high2    = nrow2;
528 
529       for (j=0; j<n; j++) {
530         if (v) {
531           if (roworiented) value = v[i*n+j];
532           else             value = v[i+j*m];
533         } else value = 0.0;
534         if (ignorezeroentries && value == 0.0 && (addv == ADD_VALUES)) continue;
535         if (in[j] >= cstart && in[j] < cend) {
536           col   = in[j] - cstart;
537           nonew = a->nonew;
538           MatSetValues_SeqAIJ_A_Private(row,col,value,addv);
539         } else if (in[j] < 0) continue;
540 #if defined(PETSC_USE_DEBUG)
541         else if (in[j] >= mat->cmap->N) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Column too large: col %D max %D",in[j],mat->cmap->N-1);
542 #endif
543         else {
544           if (mat->was_assembled) {
545             if (!aij->colmap) {
546               ierr = MatCreateColmap_MPIAIJ_Private(mat);CHKERRQ(ierr);
547             }
548 #if defined(PETSC_USE_CTABLE)
549             ierr = PetscTableFind(aij->colmap,in[j]+1,&col);CHKERRQ(ierr);
550             col--;
551 #else
552             col = aij->colmap[in[j]] - 1;
553 #endif
554             if (col < 0 && !((Mat_SeqAIJ*)(aij->B->data))->nonew) {
555               ierr = MatDisAssemble_MPIAIJ(mat);CHKERRQ(ierr);
556               col  =  in[j];
557               /* Reinitialize the variables required by MatSetValues_SeqAIJ_B_Private() */
558               B     = aij->B;
559               b     = (Mat_SeqAIJ*)B->data;
560               bimax = b->imax; bi = b->i; bilen = b->ilen; bj = b->j; ba = b->a;
561               rp2   = bj + bi[row];
562               ap2   = ba + bi[row];
563               rmax2 = bimax[row];
564               nrow2 = bilen[row];
565               low2  = 0;
566               high2 = nrow2;
567               bm    = aij->B->rmap->n;
568               ba    = b->a;
569             } else if (col < 0) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Inserting a new nonzero (%D, %D) into matrix", im[i], in[j]);
570           } else col = in[j];
571           nonew = b->nonew;
572           MatSetValues_SeqAIJ_B_Private(row,col,value,addv);
573         }
574       }
575     } else {
576       if (mat->nooffprocentries) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONG,"Setting off process row %D even though MatSetOption(,MAT_NO_OFF_PROC_ENTRIES,PETSC_TRUE) was set",im[i]);
577       if (!aij->donotstash) {
578         mat->assembled = PETSC_FALSE;
579         if (roworiented) {
580           ierr = MatStashValuesRow_Private(&mat->stash,im[i],n,in,v+i*n,(PetscBool)(ignorezeroentries && (addv == ADD_VALUES)));CHKERRQ(ierr);
581         } else {
582           ierr = MatStashValuesCol_Private(&mat->stash,im[i],n,in,v+i,m,(PetscBool)(ignorezeroentries && (addv == ADD_VALUES)));CHKERRQ(ierr);
583         }
584       }
585     }
586   }
587   PetscFunctionReturn(0);
588 }
589 
590 #undef __FUNCT__
591 #define __FUNCT__ "MatGetValues_MPIAIJ"
592 PetscErrorCode MatGetValues_MPIAIJ(Mat mat,PetscInt m,const PetscInt idxm[],PetscInt n,const PetscInt idxn[],PetscScalar v[])
593 {
594   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
595   PetscErrorCode ierr;
596   PetscInt       i,j,rstart = mat->rmap->rstart,rend = mat->rmap->rend;
597   PetscInt       cstart = mat->cmap->rstart,cend = mat->cmap->rend,row,col;
598 
599   PetscFunctionBegin;
600   for (i=0; i<m; i++) {
601     if (idxm[i] < 0) continue; /* SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Negative row: %D",idxm[i]);*/
602     if (idxm[i] >= mat->rmap->N) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Row too large: row %D max %D",idxm[i],mat->rmap->N-1);
603     if (idxm[i] >= rstart && idxm[i] < rend) {
604       row = idxm[i] - rstart;
605       for (j=0; j<n; j++) {
606         if (idxn[j] < 0) continue; /* SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Negative column: %D",idxn[j]); */
607         if (idxn[j] >= mat->cmap->N) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Column too large: col %D max %D",idxn[j],mat->cmap->N-1);
608         if (idxn[j] >= cstart && idxn[j] < cend) {
609           col  = idxn[j] - cstart;
610           ierr = MatGetValues(aij->A,1,&row,1,&col,v+i*n+j);CHKERRQ(ierr);
611         } else {
612           if (!aij->colmap) {
613             ierr = MatCreateColmap_MPIAIJ_Private(mat);CHKERRQ(ierr);
614           }
615 #if defined(PETSC_USE_CTABLE)
616           ierr = PetscTableFind(aij->colmap,idxn[j]+1,&col);CHKERRQ(ierr);
617           col--;
618 #else
619           col = aij->colmap[idxn[j]] - 1;
620 #endif
621           if ((col < 0) || (aij->garray[col] != idxn[j])) *(v+i*n+j) = 0.0;
622           else {
623             ierr = MatGetValues(aij->B,1,&row,1,&col,v+i*n+j);CHKERRQ(ierr);
624           }
625         }
626       }
627     } else SETERRQ(PETSC_COMM_SELF,PETSC_ERR_SUP,"Only local values currently supported");
628   }
629   PetscFunctionReturn(0);
630 }
631 
632 extern PetscErrorCode MatMultDiagonalBlock_MPIAIJ(Mat,Vec,Vec);
633 
634 #undef __FUNCT__
635 #define __FUNCT__ "MatAssemblyBegin_MPIAIJ"
636 PetscErrorCode MatAssemblyBegin_MPIAIJ(Mat mat,MatAssemblyType mode)
637 {
638   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
639   PetscErrorCode ierr;
640   PetscInt       nstash,reallocs;
641   InsertMode     addv;
642 
643   PetscFunctionBegin;
644   if (aij->donotstash || mat->nooffprocentries) PetscFunctionReturn(0);
645 
646   /* make sure all processors are either in INSERTMODE or ADDMODE */
647   ierr = MPI_Allreduce((PetscEnum*)&mat->insertmode,(PetscEnum*)&addv,1,MPIU_ENUM,MPI_BOR,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
648   if (addv == (ADD_VALUES|INSERT_VALUES)) SETERRQ(PetscObjectComm((PetscObject)mat),PETSC_ERR_ARG_WRONGSTATE,"Some processors inserted others added");
649   mat->insertmode = addv; /* in case this processor had no cache */
650 
651   ierr = MatStashScatterBegin_Private(mat,&mat->stash,mat->rmap->range);CHKERRQ(ierr);
652   ierr = MatStashGetInfo_Private(&mat->stash,&nstash,&reallocs);CHKERRQ(ierr);
653   ierr = PetscInfo2(aij->A,"Stash has %D entries, uses %D mallocs.\n",nstash,reallocs);CHKERRQ(ierr);
654   PetscFunctionReturn(0);
655 }
656 
657 #undef __FUNCT__
658 #define __FUNCT__ "MatAssemblyEnd_MPIAIJ"
659 PetscErrorCode MatAssemblyEnd_MPIAIJ(Mat mat,MatAssemblyType mode)
660 {
661   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
662   Mat_SeqAIJ     *a   = (Mat_SeqAIJ*)aij->A->data;
663   PetscErrorCode ierr;
664   PetscMPIInt    n;
665   PetscInt       i,j,rstart,ncols,flg;
666   PetscInt       *row,*col;
667   PetscBool      other_disassembled;
668   PetscScalar    *val;
669   InsertMode     addv = mat->insertmode;
670 
671   /* do not use 'b = (Mat_SeqAIJ*)aij->B->data' as B can be reset in disassembly */
672 
673   PetscFunctionBegin;
674   if (!aij->donotstash && !mat->nooffprocentries) {
675     while (1) {
676       ierr = MatStashScatterGetMesg_Private(&mat->stash,&n,&row,&col,&val,&flg);CHKERRQ(ierr);
677       if (!flg) break;
678 
679       for (i=0; i<n; ) {
680         /* Now identify the consecutive vals belonging to the same row */
681         for (j=i,rstart=row[j]; j<n; j++) {
682           if (row[j] != rstart) break;
683         }
684         if (j < n) ncols = j-i;
685         else       ncols = n-i;
686         /* Now assemble all these values with a single function call */
687         ierr = MatSetValues_MPIAIJ(mat,1,row+i,ncols,col+i,val+i,addv);CHKERRQ(ierr);
688 
689         i = j;
690       }
691     }
692     ierr = MatStashScatterEnd_Private(&mat->stash);CHKERRQ(ierr);
693   }
694   ierr = MatAssemblyBegin(aij->A,mode);CHKERRQ(ierr);
695   ierr = MatAssemblyEnd(aij->A,mode);CHKERRQ(ierr);
696 
697   /* determine if any processor has disassembled, if so we must
698      also disassemble ourselfs, in order that we may reassemble. */
699   /*
700      if nonzero structure of submatrix B cannot change then we know that
701      no processor disassembled thus we can skip this stuff
702   */
703   if (!((Mat_SeqAIJ*)aij->B->data)->nonew) {
704     ierr = MPI_Allreduce(&mat->was_assembled,&other_disassembled,1,MPIU_BOOL,MPI_PROD,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
705     if (mat->was_assembled && !other_disassembled) {
706       ierr = MatDisAssemble_MPIAIJ(mat);CHKERRQ(ierr);
707     }
708   }
709   if (!mat->was_assembled && mode == MAT_FINAL_ASSEMBLY) {
710     ierr = MatSetUpMultiply_MPIAIJ(mat);CHKERRQ(ierr);
711   }
712   ierr = MatSetOption(aij->B,MAT_USE_INODES,PETSC_FALSE);CHKERRQ(ierr);
713   ierr = MatSetOption(aij->B,MAT_CHECK_COMPRESSED_ROW,PETSC_FALSE);CHKERRQ(ierr);
714   ierr = MatAssemblyBegin(aij->B,mode);CHKERRQ(ierr);
715   ierr = MatAssemblyEnd(aij->B,mode);CHKERRQ(ierr);
716 
717   ierr = PetscFree2(aij->rowvalues,aij->rowindices);CHKERRQ(ierr);
718 
719   aij->rowvalues = 0;
720 
721   /* used by MatAXPY() */
722   a->xtoy = 0; ((Mat_SeqAIJ*)aij->B->data)->xtoy = 0;   /* b->xtoy = 0 */
723   a->XtoY = 0; ((Mat_SeqAIJ*)aij->B->data)->XtoY = 0;   /* b->XtoY = 0 */
724 
725   ierr = VecDestroy(&aij->diag);CHKERRQ(ierr);
726   if (a->inode.size) mat->ops->multdiagonalblock = MatMultDiagonalBlock_MPIAIJ;
727   PetscFunctionReturn(0);
728 }
729 
730 #undef __FUNCT__
731 #define __FUNCT__ "MatZeroEntries_MPIAIJ"
732 PetscErrorCode MatZeroEntries_MPIAIJ(Mat A)
733 {
734   Mat_MPIAIJ     *l = (Mat_MPIAIJ*)A->data;
735   PetscErrorCode ierr;
736 
737   PetscFunctionBegin;
738   ierr = MatZeroEntries(l->A);CHKERRQ(ierr);
739   ierr = MatZeroEntries(l->B);CHKERRQ(ierr);
740   PetscFunctionReturn(0);
741 }
742 
743 #undef __FUNCT__
744 #define __FUNCT__ "MatZeroRows_MPIAIJ"
745 PetscErrorCode MatZeroRows_MPIAIJ(Mat A,PetscInt N,const PetscInt rows[],PetscScalar diag,Vec x,Vec b)
746 {
747   Mat_MPIAIJ        *l = (Mat_MPIAIJ*)A->data;
748   PetscErrorCode    ierr;
749   PetscMPIInt       size = l->size,imdex,n,rank = l->rank,tag = ((PetscObject)A)->tag,lastidx = -1;
750   PetscInt          i,*owners = A->rmap->range;
751   PetscInt          *nprocs,j,idx,nsends,row;
752   PetscInt          nmax,*svalues,*starts,*owner,nrecvs;
753   PetscInt          *rvalues,count,base,slen,*source;
754   PetscInt          *lens,*lrows,*values,rstart=A->rmap->rstart;
755   MPI_Comm          comm;
756   MPI_Request       *send_waits,*recv_waits;
757   MPI_Status        recv_status,*send_status;
758   const PetscScalar *xx;
759   PetscScalar       *bb;
760 #if defined(PETSC_DEBUG)
761   PetscBool found = PETSC_FALSE;
762 #endif
763 
764   PetscFunctionBegin;
765   ierr = PetscObjectGetComm((PetscObject)A,&comm);CHKERRQ(ierr);
766   /*  first count number of contributors to each processor */
767   ierr = PetscMalloc(2*size*sizeof(PetscInt),&nprocs);CHKERRQ(ierr);
768   ierr = PetscMemzero(nprocs,2*size*sizeof(PetscInt));CHKERRQ(ierr);
769   ierr = PetscMalloc((N+1)*sizeof(PetscInt),&owner);CHKERRQ(ierr); /* see note*/
770   j    = 0;
771   for (i=0; i<N; i++) {
772     if (lastidx > (idx = rows[i])) j = 0;
773     lastidx = idx;
774     for (; j<size; j++) {
775       if (idx >= owners[j] && idx < owners[j+1]) {
776         nprocs[2*j]++;
777         nprocs[2*j+1] = 1;
778         owner[i]      = j;
779 #if defined(PETSC_DEBUG)
780         found = PETSC_TRUE;
781 #endif
782         break;
783       }
784     }
785 #if defined(PETSC_DEBUG)
786     if (!found) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Index out of range");
787     found = PETSC_FALSE;
788 #endif
789   }
790   nsends = 0;
791   for (i=0; i<size; i++) nsends += nprocs[2*i+1];
792 
793   if (A->nooffproczerorows) {
794     if (nsends > 1) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONG,"You called MatSetOption(,MAT_NO_OFF_PROC_ZERO_ROWS,PETSC_TRUE) but set an off process zero row");
795     nrecvs = nsends;
796     nmax   = N;
797   } else {
798     /* inform other processors of number of messages and max length*/
799     ierr = PetscMaxSum(comm,nprocs,&nmax,&nrecvs);CHKERRQ(ierr);
800   }
801 
802   /* post receives:   */
803   ierr = PetscMalloc((nrecvs+1)*(nmax+1)*sizeof(PetscInt),&rvalues);CHKERRQ(ierr);
804   ierr = PetscMalloc((nrecvs+1)*sizeof(MPI_Request),&recv_waits);CHKERRQ(ierr);
805   for (i=0; i<nrecvs; i++) {
806     ierr = MPI_Irecv(rvalues+nmax*i,nmax,MPIU_INT,MPI_ANY_SOURCE,tag,comm,recv_waits+i);CHKERRQ(ierr);
807   }
808 
809   /* do sends:
810       1) starts[i] gives the starting index in svalues for stuff going to
811          the ith processor
812   */
813   ierr = PetscMalloc((N+1)*sizeof(PetscInt),&svalues);CHKERRQ(ierr);
814   ierr = PetscMalloc((nsends+1)*sizeof(MPI_Request),&send_waits);CHKERRQ(ierr);
815   ierr = PetscMalloc((size+1)*sizeof(PetscInt),&starts);CHKERRQ(ierr);
816 
817   starts[0] = 0;
818   for (i=1; i<size; i++) starts[i] = starts[i-1] + nprocs[2*i-2];
819   for (i=0; i<N; i++) svalues[starts[owner[i]]++] = rows[i];
820 
821   starts[0] = 0;
822   for (i=1; i<size+1; i++) starts[i] = starts[i-1] + nprocs[2*i-2];
823   count = 0;
824   for (i=0; i<size; i++) {
825     if (nprocs[2*i+1]) {
826       ierr = MPI_Isend(svalues+starts[i],nprocs[2*i],MPIU_INT,i,tag,comm,send_waits+count++);CHKERRQ(ierr);
827     }
828   }
829   ierr = PetscFree(starts);CHKERRQ(ierr);
830 
831   base = owners[rank];
832 
833   /*  wait on receives */
834   ierr  = PetscMalloc2(nrecvs,PetscInt,&lens,nrecvs,PetscInt,&source);CHKERRQ(ierr);
835   count = nrecvs; slen = 0;
836   while (count) {
837     ierr = MPI_Waitany(nrecvs,recv_waits,&imdex,&recv_status);CHKERRQ(ierr);
838     /* unpack receives into our local space */
839     ierr = MPI_Get_count(&recv_status,MPIU_INT,&n);CHKERRQ(ierr);
840 
841     source[imdex] = recv_status.MPI_SOURCE;
842     lens[imdex]   = n;
843     slen         += n;
844     count--;
845   }
846   ierr = PetscFree(recv_waits);CHKERRQ(ierr);
847 
848   /* move the data into the send scatter */
849   ierr  = PetscMalloc((slen+1)*sizeof(PetscInt),&lrows);CHKERRQ(ierr);
850   count = 0;
851   for (i=0; i<nrecvs; i++) {
852     values = rvalues + i*nmax;
853     for (j=0; j<lens[i]; j++) lrows[count++] = values[j] - base;
854   }
855   ierr = PetscFree(rvalues);CHKERRQ(ierr);
856   ierr = PetscFree2(lens,source);CHKERRQ(ierr);
857   ierr = PetscFree(owner);CHKERRQ(ierr);
858   ierr = PetscFree(nprocs);CHKERRQ(ierr);
859 
860   /* fix right hand side if needed */
861   if (x && b) {
862     ierr = VecGetArrayRead(x,&xx);CHKERRQ(ierr);
863     ierr = VecGetArray(b,&bb);CHKERRQ(ierr);
864     for (i=0; i<slen; i++) bb[lrows[i]] = diag*xx[lrows[i]];
865     ierr = VecRestoreArrayRead(x,&xx);CHKERRQ(ierr);
866     ierr = VecRestoreArray(b,&bb);CHKERRQ(ierr);
867   }
868   /*
869         Zero the required rows. If the "diagonal block" of the matrix
870      is square and the user wishes to set the diagonal we use separate
871      code so that MatSetValues() is not called for each diagonal allocating
872      new memory, thus calling lots of mallocs and slowing things down.
873 
874   */
875   /* must zero l->B before l->A because the (diag) case below may put values into l->B*/
876   ierr = MatZeroRows(l->B,slen,lrows,0.0,0,0);CHKERRQ(ierr);
877   if ((diag != 0.0) && (l->A->rmap->N == l->A->cmap->N)) {
878     ierr = MatZeroRows(l->A,slen,lrows,diag,0,0);CHKERRQ(ierr);
879   } else if (diag != 0.0) {
880     ierr = MatZeroRows(l->A,slen,lrows,0.0,0,0);CHKERRQ(ierr);
881     if (((Mat_SeqAIJ*)l->A->data)->nonew) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_SUP,"MatZeroRows() on rectangular matrices cannot be used with the Mat options\nMAT_NEW_NONZERO_LOCATIONS,MAT_NEW_NONZERO_LOCATION_ERR,MAT_NEW_NONZERO_ALLOCATION_ERR");
882     for (i = 0; i < slen; i++) {
883       row  = lrows[i] + rstart;
884       ierr = MatSetValues(A,1,&row,1,&row,&diag,INSERT_VALUES);CHKERRQ(ierr);
885     }
886     ierr = MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
887     ierr = MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
888   } else {
889     ierr = MatZeroRows(l->A,slen,lrows,0.0,0,0);CHKERRQ(ierr);
890   }
891   ierr = PetscFree(lrows);CHKERRQ(ierr);
892 
893   /* wait on sends */
894   if (nsends) {
895     ierr = PetscMalloc(nsends*sizeof(MPI_Status),&send_status);CHKERRQ(ierr);
896     ierr = MPI_Waitall(nsends,send_waits,send_status);CHKERRQ(ierr);
897     ierr = PetscFree(send_status);CHKERRQ(ierr);
898   }
899   ierr = PetscFree(send_waits);CHKERRQ(ierr);
900   ierr = PetscFree(svalues);CHKERRQ(ierr);
901   PetscFunctionReturn(0);
902 }
903 
904 #undef __FUNCT__
905 #define __FUNCT__ "MatZeroRowsColumns_MPIAIJ"
906 PetscErrorCode MatZeroRowsColumns_MPIAIJ(Mat A,PetscInt N,const PetscInt rows[],PetscScalar diag,Vec x,Vec b)
907 {
908   Mat_MPIAIJ        *l = (Mat_MPIAIJ*)A->data;
909   PetscErrorCode    ierr;
910   PetscMPIInt       size = l->size,imdex,n,rank = l->rank,tag = ((PetscObject)A)->tag,lastidx = -1;
911   PetscInt          i,*owners = A->rmap->range;
912   PetscInt          *nprocs,j,idx,nsends;
913   PetscInt          nmax,*svalues,*starts,*owner,nrecvs;
914   PetscInt          *rvalues,count,base,slen,*source;
915   PetscInt          *lens,*lrows,*values,m;
916   MPI_Comm          comm;
917   MPI_Request       *send_waits,*recv_waits;
918   MPI_Status        recv_status,*send_status;
919   const PetscScalar *xx;
920   PetscScalar       *bb,*mask;
921   Vec               xmask,lmask;
922   Mat_SeqAIJ        *aij = (Mat_SeqAIJ*)l->B->data;
923   const PetscInt    *aj, *ii,*ridx;
924   PetscScalar       *aa;
925 #if defined(PETSC_DEBUG)
926   PetscBool found = PETSC_FALSE;
927 #endif
928 
929   PetscFunctionBegin;
930   ierr = PetscObjectGetComm((PetscObject)A,&comm);CHKERRQ(ierr);
931   /*  first count number of contributors to each processor */
932   ierr = PetscMalloc(2*size*sizeof(PetscInt),&nprocs);CHKERRQ(ierr);
933   ierr = PetscMemzero(nprocs,2*size*sizeof(PetscInt));CHKERRQ(ierr);
934   ierr = PetscMalloc((N+1)*sizeof(PetscInt),&owner);CHKERRQ(ierr); /* see note*/
935   j    = 0;
936   for (i=0; i<N; i++) {
937     if (lastidx > (idx = rows[i])) j = 0;
938     lastidx = idx;
939     for (; j<size; j++) {
940       if (idx >= owners[j] && idx < owners[j+1]) {
941         nprocs[2*j]++;
942         nprocs[2*j+1] = 1;
943         owner[i]      = j;
944 #if defined(PETSC_DEBUG)
945         found = PETSC_TRUE;
946 #endif
947         break;
948       }
949     }
950 #if defined(PETSC_DEBUG)
951     if (!found) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Index out of range");
952     found = PETSC_FALSE;
953 #endif
954   }
955   nsends = 0;  for (i=0; i<size; i++) nsends += nprocs[2*i+1];
956 
957   /* inform other processors of number of messages and max length*/
958   ierr = PetscMaxSum(comm,nprocs,&nmax,&nrecvs);CHKERRQ(ierr);
959 
960   /* post receives:   */
961   ierr = PetscMalloc((nrecvs+1)*(nmax+1)*sizeof(PetscInt),&rvalues);CHKERRQ(ierr);
962   ierr = PetscMalloc((nrecvs+1)*sizeof(MPI_Request),&recv_waits);CHKERRQ(ierr);
963   for (i=0; i<nrecvs; i++) {
964     ierr = MPI_Irecv(rvalues+nmax*i,nmax,MPIU_INT,MPI_ANY_SOURCE,tag,comm,recv_waits+i);CHKERRQ(ierr);
965   }
966 
967   /* do sends:
968       1) starts[i] gives the starting index in svalues for stuff going to
969          the ith processor
970   */
971   ierr = PetscMalloc((N+1)*sizeof(PetscInt),&svalues);CHKERRQ(ierr);
972   ierr = PetscMalloc((nsends+1)*sizeof(MPI_Request),&send_waits);CHKERRQ(ierr);
973   ierr = PetscMalloc((size+1)*sizeof(PetscInt),&starts);CHKERRQ(ierr);
974 
975   starts[0] = 0;
976   for (i=1; i<size; i++) starts[i] = starts[i-1] + nprocs[2*i-2];
977   for (i=0; i<N; i++) svalues[starts[owner[i]]++] = rows[i];
978 
979   starts[0] = 0;
980   for (i=1; i<size+1; i++) starts[i] = starts[i-1] + nprocs[2*i-2];
981   count = 0;
982   for (i=0; i<size; i++) {
983     if (nprocs[2*i+1]) {
984       ierr = MPI_Isend(svalues+starts[i],nprocs[2*i],MPIU_INT,i,tag,comm,send_waits+count++);CHKERRQ(ierr);
985     }
986   }
987   ierr = PetscFree(starts);CHKERRQ(ierr);
988 
989   base = owners[rank];
990 
991   /*  wait on receives */
992   ierr  = PetscMalloc2(nrecvs,PetscInt,&lens,nrecvs,PetscInt,&source);CHKERRQ(ierr);
993   count = nrecvs; slen = 0;
994   while (count) {
995     ierr = MPI_Waitany(nrecvs,recv_waits,&imdex,&recv_status);CHKERRQ(ierr);
996     /* unpack receives into our local space */
997     ierr = MPI_Get_count(&recv_status,MPIU_INT,&n);CHKERRQ(ierr);
998 
999     source[imdex] = recv_status.MPI_SOURCE;
1000     lens[imdex]   = n;
1001     slen         += n;
1002     count--;
1003   }
1004   ierr = PetscFree(recv_waits);CHKERRQ(ierr);
1005 
1006   /* move the data into the send scatter */
1007   ierr  = PetscMalloc((slen+1)*sizeof(PetscInt),&lrows);CHKERRQ(ierr);
1008   count = 0;
1009   for (i=0; i<nrecvs; i++) {
1010     values = rvalues + i*nmax;
1011     for (j=0; j<lens[i]; j++) lrows[count++] = values[j] - base;
1012   }
1013   ierr = PetscFree(rvalues);CHKERRQ(ierr);
1014   ierr = PetscFree2(lens,source);CHKERRQ(ierr);
1015   ierr = PetscFree(owner);CHKERRQ(ierr);
1016   ierr = PetscFree(nprocs);CHKERRQ(ierr);
1017   /* lrows are the local rows to be zeroed, slen is the number of local rows */
1018 
1019   /* zero diagonal part of matrix */
1020   ierr = MatZeroRowsColumns(l->A,slen,lrows,diag,x,b);CHKERRQ(ierr);
1021 
1022   /* handle off diagonal part of matrix */
1023   ierr = MatGetVecs(A,&xmask,NULL);CHKERRQ(ierr);
1024   ierr = VecDuplicate(l->lvec,&lmask);CHKERRQ(ierr);
1025   ierr = VecGetArray(xmask,&bb);CHKERRQ(ierr);
1026   for (i=0; i<slen; i++) bb[lrows[i]] = 1;
1027   ierr = VecRestoreArray(xmask,&bb);CHKERRQ(ierr);
1028   ierr = VecScatterBegin(l->Mvctx,xmask,lmask,ADD_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1029   ierr = VecScatterEnd(l->Mvctx,xmask,lmask,ADD_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1030   ierr = VecDestroy(&xmask);CHKERRQ(ierr);
1031   if (x) {
1032     ierr = VecScatterBegin(l->Mvctx,x,l->lvec,ADD_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1033     ierr = VecScatterEnd(l->Mvctx,x,l->lvec,ADD_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1034     ierr = VecGetArrayRead(l->lvec,&xx);CHKERRQ(ierr);
1035     ierr = VecGetArray(b,&bb);CHKERRQ(ierr);
1036   }
1037   ierr = VecGetArray(lmask,&mask);CHKERRQ(ierr);
1038 
1039   /* remove zeroed rows of off diagonal matrix */
1040   ii = aij->i;
1041   for (i=0; i<slen; i++) {
1042     ierr = PetscMemzero(aij->a + ii[lrows[i]],(ii[lrows[i]+1] - ii[lrows[i]])*sizeof(PetscScalar));CHKERRQ(ierr);
1043   }
1044 
1045   /* loop over all elements of off process part of matrix zeroing removed columns*/
1046   if (aij->compressedrow.use) {
1047     m    = aij->compressedrow.nrows;
1048     ii   = aij->compressedrow.i;
1049     ridx = aij->compressedrow.rindex;
1050     for (i=0; i<m; i++) {
1051       n  = ii[i+1] - ii[i];
1052       aj = aij->j + ii[i];
1053       aa = aij->a + ii[i];
1054 
1055       for (j=0; j<n; j++) {
1056         if (PetscAbsScalar(mask[*aj])) {
1057           if (b) bb[*ridx] -= *aa*xx[*aj];
1058           *aa = 0.0;
1059         }
1060         aa++;
1061         aj++;
1062       }
1063       ridx++;
1064     }
1065   } else { /* do not use compressed row format */
1066     m = l->B->rmap->n;
1067     for (i=0; i<m; i++) {
1068       n  = ii[i+1] - ii[i];
1069       aj = aij->j + ii[i];
1070       aa = aij->a + ii[i];
1071       for (j=0; j<n; j++) {
1072         if (PetscAbsScalar(mask[*aj])) {
1073           if (b) bb[i] -= *aa*xx[*aj];
1074           *aa = 0.0;
1075         }
1076         aa++;
1077         aj++;
1078       }
1079     }
1080   }
1081   if (x) {
1082     ierr = VecRestoreArray(b,&bb);CHKERRQ(ierr);
1083     ierr = VecRestoreArrayRead(l->lvec,&xx);CHKERRQ(ierr);
1084   }
1085   ierr = VecRestoreArray(lmask,&mask);CHKERRQ(ierr);
1086   ierr = VecDestroy(&lmask);CHKERRQ(ierr);
1087   ierr = PetscFree(lrows);CHKERRQ(ierr);
1088 
1089   /* wait on sends */
1090   if (nsends) {
1091     ierr = PetscMalloc(nsends*sizeof(MPI_Status),&send_status);CHKERRQ(ierr);
1092     ierr = MPI_Waitall(nsends,send_waits,send_status);CHKERRQ(ierr);
1093     ierr = PetscFree(send_status);CHKERRQ(ierr);
1094   }
1095   ierr = PetscFree(send_waits);CHKERRQ(ierr);
1096   ierr = PetscFree(svalues);CHKERRQ(ierr);
1097   PetscFunctionReturn(0);
1098 }
1099 
1100 #undef __FUNCT__
1101 #define __FUNCT__ "MatMult_MPIAIJ"
1102 PetscErrorCode MatMult_MPIAIJ(Mat A,Vec xx,Vec yy)
1103 {
1104   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
1105   PetscErrorCode ierr;
1106   PetscInt       nt;
1107 
1108   PetscFunctionBegin;
1109   ierr = VecGetLocalSize(xx,&nt);CHKERRQ(ierr);
1110   if (nt != A->cmap->n) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_SIZ,"Incompatible partition of A (%D) and xx (%D)",A->cmap->n,nt);
1111   ierr = VecScatterBegin(a->Mvctx,xx,a->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1112   ierr = (*a->A->ops->mult)(a->A,xx,yy);CHKERRQ(ierr);
1113   ierr = VecScatterEnd(a->Mvctx,xx,a->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1114   ierr = (*a->B->ops->multadd)(a->B,a->lvec,yy,yy);CHKERRQ(ierr);
1115   PetscFunctionReturn(0);
1116 }
1117 
1118 #undef __FUNCT__
1119 #define __FUNCT__ "MatMultDiagonalBlock_MPIAIJ"
1120 PetscErrorCode MatMultDiagonalBlock_MPIAIJ(Mat A,Vec bb,Vec xx)
1121 {
1122   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
1123   PetscErrorCode ierr;
1124 
1125   PetscFunctionBegin;
1126   ierr = MatMultDiagonalBlock(a->A,bb,xx);CHKERRQ(ierr);
1127   PetscFunctionReturn(0);
1128 }
1129 
1130 #undef __FUNCT__
1131 #define __FUNCT__ "MatMultAdd_MPIAIJ"
1132 PetscErrorCode MatMultAdd_MPIAIJ(Mat A,Vec xx,Vec yy,Vec zz)
1133 {
1134   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
1135   PetscErrorCode ierr;
1136 
1137   PetscFunctionBegin;
1138   ierr = VecScatterBegin(a->Mvctx,xx,a->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1139   ierr = (*a->A->ops->multadd)(a->A,xx,yy,zz);CHKERRQ(ierr);
1140   ierr = VecScatterEnd(a->Mvctx,xx,a->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1141   ierr = (*a->B->ops->multadd)(a->B,a->lvec,zz,zz);CHKERRQ(ierr);
1142   PetscFunctionReturn(0);
1143 }
1144 
1145 #undef __FUNCT__
1146 #define __FUNCT__ "MatMultTranspose_MPIAIJ"
1147 PetscErrorCode MatMultTranspose_MPIAIJ(Mat A,Vec xx,Vec yy)
1148 {
1149   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
1150   PetscErrorCode ierr;
1151   PetscBool      merged;
1152 
1153   PetscFunctionBegin;
1154   ierr = VecScatterGetMerged(a->Mvctx,&merged);CHKERRQ(ierr);
1155   /* do nondiagonal part */
1156   ierr = (*a->B->ops->multtranspose)(a->B,xx,a->lvec);CHKERRQ(ierr);
1157   if (!merged) {
1158     /* send it on its way */
1159     ierr = VecScatterBegin(a->Mvctx,a->lvec,yy,ADD_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
1160     /* do local part */
1161     ierr = (*a->A->ops->multtranspose)(a->A,xx,yy);CHKERRQ(ierr);
1162     /* receive remote parts: note this assumes the values are not actually */
1163     /* added in yy until the next line, */
1164     ierr = VecScatterEnd(a->Mvctx,a->lvec,yy,ADD_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
1165   } else {
1166     /* do local part */
1167     ierr = (*a->A->ops->multtranspose)(a->A,xx,yy);CHKERRQ(ierr);
1168     /* send it on its way */
1169     ierr = VecScatterBegin(a->Mvctx,a->lvec,yy,ADD_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
1170     /* values actually were received in the Begin() but we need to call this nop */
1171     ierr = VecScatterEnd(a->Mvctx,a->lvec,yy,ADD_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
1172   }
1173   PetscFunctionReturn(0);
1174 }
1175 
1176 #undef __FUNCT__
1177 #define __FUNCT__ "MatIsTranspose_MPIAIJ"
1178 PetscErrorCode  MatIsTranspose_MPIAIJ(Mat Amat,Mat Bmat,PetscReal tol,PetscBool  *f)
1179 {
1180   MPI_Comm       comm;
1181   Mat_MPIAIJ     *Aij = (Mat_MPIAIJ*) Amat->data, *Bij;
1182   Mat            Adia = Aij->A, Bdia, Aoff,Boff,*Aoffs,*Boffs;
1183   IS             Me,Notme;
1184   PetscErrorCode ierr;
1185   PetscInt       M,N,first,last,*notme,i;
1186   PetscMPIInt    size;
1187 
1188   PetscFunctionBegin;
1189   /* Easy test: symmetric diagonal block */
1190   Bij  = (Mat_MPIAIJ*) Bmat->data; Bdia = Bij->A;
1191   ierr = MatIsTranspose(Adia,Bdia,tol,f);CHKERRQ(ierr);
1192   if (!*f) PetscFunctionReturn(0);
1193   ierr = PetscObjectGetComm((PetscObject)Amat,&comm);CHKERRQ(ierr);
1194   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
1195   if (size == 1) PetscFunctionReturn(0);
1196 
1197   /* Hard test: off-diagonal block. This takes a MatGetSubMatrix. */
1198   ierr = MatGetSize(Amat,&M,&N);CHKERRQ(ierr);
1199   ierr = MatGetOwnershipRange(Amat,&first,&last);CHKERRQ(ierr);
1200   ierr = PetscMalloc((N-last+first)*sizeof(PetscInt),&notme);CHKERRQ(ierr);
1201   for (i=0; i<first; i++) notme[i] = i;
1202   for (i=last; i<M; i++) notme[i-last+first] = i;
1203   ierr = ISCreateGeneral(MPI_COMM_SELF,N-last+first,notme,PETSC_COPY_VALUES,&Notme);CHKERRQ(ierr);
1204   ierr = ISCreateStride(MPI_COMM_SELF,last-first,first,1,&Me);CHKERRQ(ierr);
1205   ierr = MatGetSubMatrices(Amat,1,&Me,&Notme,MAT_INITIAL_MATRIX,&Aoffs);CHKERRQ(ierr);
1206   Aoff = Aoffs[0];
1207   ierr = MatGetSubMatrices(Bmat,1,&Notme,&Me,MAT_INITIAL_MATRIX,&Boffs);CHKERRQ(ierr);
1208   Boff = Boffs[0];
1209   ierr = MatIsTranspose(Aoff,Boff,tol,f);CHKERRQ(ierr);
1210   ierr = MatDestroyMatrices(1,&Aoffs);CHKERRQ(ierr);
1211   ierr = MatDestroyMatrices(1,&Boffs);CHKERRQ(ierr);
1212   ierr = ISDestroy(&Me);CHKERRQ(ierr);
1213   ierr = ISDestroy(&Notme);CHKERRQ(ierr);
1214   ierr = PetscFree(notme);CHKERRQ(ierr);
1215   PetscFunctionReturn(0);
1216 }
1217 
1218 #undef __FUNCT__
1219 #define __FUNCT__ "MatMultTransposeAdd_MPIAIJ"
1220 PetscErrorCode MatMultTransposeAdd_MPIAIJ(Mat A,Vec xx,Vec yy,Vec zz)
1221 {
1222   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
1223   PetscErrorCode ierr;
1224 
1225   PetscFunctionBegin;
1226   /* do nondiagonal part */
1227   ierr = (*a->B->ops->multtranspose)(a->B,xx,a->lvec);CHKERRQ(ierr);
1228   /* send it on its way */
1229   ierr = VecScatterBegin(a->Mvctx,a->lvec,zz,ADD_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
1230   /* do local part */
1231   ierr = (*a->A->ops->multtransposeadd)(a->A,xx,yy,zz);CHKERRQ(ierr);
1232   /* receive remote parts */
1233   ierr = VecScatterEnd(a->Mvctx,a->lvec,zz,ADD_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
1234   PetscFunctionReturn(0);
1235 }
1236 
1237 /*
1238   This only works correctly for square matrices where the subblock A->A is the
1239    diagonal block
1240 */
1241 #undef __FUNCT__
1242 #define __FUNCT__ "MatGetDiagonal_MPIAIJ"
1243 PetscErrorCode MatGetDiagonal_MPIAIJ(Mat A,Vec v)
1244 {
1245   PetscErrorCode ierr;
1246   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
1247 
1248   PetscFunctionBegin;
1249   if (A->rmap->N != A->cmap->N) SETERRQ(PetscObjectComm((PetscObject)A),PETSC_ERR_SUP,"Supports only square matrix where A->A is diag block");
1250   if (A->rmap->rstart != A->cmap->rstart || A->rmap->rend != A->cmap->rend) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_SIZ,"row partition must equal col partition");
1251   ierr = MatGetDiagonal(a->A,v);CHKERRQ(ierr);
1252   PetscFunctionReturn(0);
1253 }
1254 
1255 #undef __FUNCT__
1256 #define __FUNCT__ "MatScale_MPIAIJ"
1257 PetscErrorCode MatScale_MPIAIJ(Mat A,PetscScalar aa)
1258 {
1259   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
1260   PetscErrorCode ierr;
1261 
1262   PetscFunctionBegin;
1263   ierr = MatScale(a->A,aa);CHKERRQ(ierr);
1264   ierr = MatScale(a->B,aa);CHKERRQ(ierr);
1265   PetscFunctionReturn(0);
1266 }
1267 
1268 #undef __FUNCT__
1269 #define __FUNCT__ "MatDestroy_MPIAIJ"
1270 PetscErrorCode MatDestroy_MPIAIJ(Mat mat)
1271 {
1272   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
1273   PetscErrorCode ierr;
1274 
1275   PetscFunctionBegin;
1276 #if defined(PETSC_USE_LOG)
1277   PetscLogObjectState((PetscObject)mat,"Rows=%D, Cols=%D",mat->rmap->N,mat->cmap->N);
1278 #endif
1279   ierr = MatStashDestroy_Private(&mat->stash);CHKERRQ(ierr);
1280   ierr = VecDestroy(&aij->diag);CHKERRQ(ierr);
1281   ierr = MatDestroy(&aij->A);CHKERRQ(ierr);
1282   ierr = MatDestroy(&aij->B);CHKERRQ(ierr);
1283 #if defined(PETSC_USE_CTABLE)
1284   ierr = PetscTableDestroy(&aij->colmap);CHKERRQ(ierr);
1285 #else
1286   ierr = PetscFree(aij->colmap);CHKERRQ(ierr);
1287 #endif
1288   ierr = PetscFree(aij->garray);CHKERRQ(ierr);
1289   ierr = VecDestroy(&aij->lvec);CHKERRQ(ierr);
1290   ierr = VecScatterDestroy(&aij->Mvctx);CHKERRQ(ierr);
1291   ierr = PetscFree2(aij->rowvalues,aij->rowindices);CHKERRQ(ierr);
1292   ierr = PetscFree(aij->ld);CHKERRQ(ierr);
1293   ierr = PetscFree(mat->data);CHKERRQ(ierr);
1294 
1295   ierr = PetscObjectChangeTypeName((PetscObject)mat,0);CHKERRQ(ierr);
1296   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatStoreValues_C",NULL);CHKERRQ(ierr);
1297   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatRetrieveValues_C",NULL);CHKERRQ(ierr);
1298   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatGetDiagonalBlock_C",NULL);CHKERRQ(ierr);
1299   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatIsTranspose_C",NULL);CHKERRQ(ierr);
1300   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatMPIAIJSetPreallocation_C",NULL);CHKERRQ(ierr);
1301   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatMPIAIJSetPreallocationCSR_C",NULL);CHKERRQ(ierr);
1302   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatDiagonalScaleLocal_C",NULL);CHKERRQ(ierr);
1303   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatConvert_mpiaij_mpisbaij_C",NULL);CHKERRQ(ierr);
1304   PetscFunctionReturn(0);
1305 }
1306 
1307 #undef __FUNCT__
1308 #define __FUNCT__ "MatView_MPIAIJ_Binary"
1309 PetscErrorCode MatView_MPIAIJ_Binary(Mat mat,PetscViewer viewer)
1310 {
1311   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
1312   Mat_SeqAIJ     *A   = (Mat_SeqAIJ*)aij->A->data;
1313   Mat_SeqAIJ     *B   = (Mat_SeqAIJ*)aij->B->data;
1314   PetscErrorCode ierr;
1315   PetscMPIInt    rank,size,tag = ((PetscObject)viewer)->tag;
1316   int            fd;
1317   PetscInt       nz,header[4],*row_lengths,*range=0,rlen,i;
1318   PetscInt       nzmax,*column_indices,j,k,col,*garray = aij->garray,cnt,cstart = mat->cmap->rstart,rnz;
1319   PetscScalar    *column_values;
1320   PetscInt       message_count,flowcontrolcount;
1321   FILE           *file;
1322 
1323   PetscFunctionBegin;
1324   ierr = MPI_Comm_rank(PetscObjectComm((PetscObject)mat),&rank);CHKERRQ(ierr);
1325   ierr = MPI_Comm_size(PetscObjectComm((PetscObject)mat),&size);CHKERRQ(ierr);
1326   nz   = A->nz + B->nz;
1327   if (!rank) {
1328     header[0] = MAT_FILE_CLASSID;
1329     header[1] = mat->rmap->N;
1330     header[2] = mat->cmap->N;
1331 
1332     ierr = MPI_Reduce(&nz,&header[3],1,MPIU_INT,MPI_SUM,0,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1333     ierr = PetscViewerBinaryGetDescriptor(viewer,&fd);CHKERRQ(ierr);
1334     ierr = PetscBinaryWrite(fd,header,4,PETSC_INT,PETSC_TRUE);CHKERRQ(ierr);
1335     /* get largest number of rows any processor has */
1336     rlen  = mat->rmap->n;
1337     range = mat->rmap->range;
1338     for (i=1; i<size; i++) rlen = PetscMax(rlen,range[i+1] - range[i]);
1339   } else {
1340     ierr = MPI_Reduce(&nz,0,1,MPIU_INT,MPI_SUM,0,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1341     rlen = mat->rmap->n;
1342   }
1343 
1344   /* load up the local row counts */
1345   ierr = PetscMalloc((rlen+1)*sizeof(PetscInt),&row_lengths);CHKERRQ(ierr);
1346   for (i=0; i<mat->rmap->n; i++) row_lengths[i] = A->i[i+1] - A->i[i] + B->i[i+1] - B->i[i];
1347 
1348   /* store the row lengths to the file */
1349   ierr = PetscViewerFlowControlStart(viewer,&message_count,&flowcontrolcount);CHKERRQ(ierr);
1350   if (!rank) {
1351     ierr = PetscBinaryWrite(fd,row_lengths,mat->rmap->n,PETSC_INT,PETSC_TRUE);CHKERRQ(ierr);
1352     for (i=1; i<size; i++) {
1353       ierr = PetscViewerFlowControlStepMaster(viewer,i,&message_count,flowcontrolcount);CHKERRQ(ierr);
1354       rlen = range[i+1] - range[i];
1355       ierr = MPIULong_Recv(row_lengths,rlen,MPIU_INT,i,tag,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1356       ierr = PetscBinaryWrite(fd,row_lengths,rlen,PETSC_INT,PETSC_TRUE);CHKERRQ(ierr);
1357     }
1358     ierr = PetscViewerFlowControlEndMaster(viewer,&message_count);CHKERRQ(ierr);
1359   } else {
1360     ierr = PetscViewerFlowControlStepWorker(viewer,rank,&message_count);CHKERRQ(ierr);
1361     ierr = MPIULong_Send(row_lengths,mat->rmap->n,MPIU_INT,0,tag,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1362     ierr = PetscViewerFlowControlEndWorker(viewer,&message_count);CHKERRQ(ierr);
1363   }
1364   ierr = PetscFree(row_lengths);CHKERRQ(ierr);
1365 
1366   /* load up the local column indices */
1367   nzmax = nz; /* th processor needs space a largest processor needs */
1368   ierr  = MPI_Reduce(&nz,&nzmax,1,MPIU_INT,MPI_MAX,0,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1369   ierr  = PetscMalloc((nzmax+1)*sizeof(PetscInt),&column_indices);CHKERRQ(ierr);
1370   cnt   = 0;
1371   for (i=0; i<mat->rmap->n; i++) {
1372     for (j=B->i[i]; j<B->i[i+1]; j++) {
1373       if ((col = garray[B->j[j]]) > cstart) break;
1374       column_indices[cnt++] = col;
1375     }
1376     for (k=A->i[i]; k<A->i[i+1]; k++) column_indices[cnt++] = A->j[k] + cstart;
1377     for (; j<B->i[i+1]; j++) column_indices[cnt++] = garray[B->j[j]];
1378   }
1379   if (cnt != A->nz + B->nz) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_LIB,"Internal PETSc error: cnt = %D nz = %D",cnt,A->nz+B->nz);
1380 
1381   /* store the column indices to the file */
1382   ierr = PetscViewerFlowControlStart(viewer,&message_count,&flowcontrolcount);CHKERRQ(ierr);
1383   if (!rank) {
1384     MPI_Status status;
1385     ierr = PetscBinaryWrite(fd,column_indices,nz,PETSC_INT,PETSC_TRUE);CHKERRQ(ierr);
1386     for (i=1; i<size; i++) {
1387       ierr = PetscViewerFlowControlStepMaster(viewer,i,&message_count,flowcontrolcount);CHKERRQ(ierr);
1388       ierr = MPI_Recv(&rnz,1,MPIU_INT,i,tag,PetscObjectComm((PetscObject)mat),&status);CHKERRQ(ierr);
1389       if (rnz > nzmax) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_LIB,"Internal PETSc error: nz = %D nzmax = %D",nz,nzmax);
1390       ierr = MPIULong_Recv(column_indices,rnz,MPIU_INT,i,tag,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1391       ierr = PetscBinaryWrite(fd,column_indices,rnz,PETSC_INT,PETSC_TRUE);CHKERRQ(ierr);
1392     }
1393     ierr = PetscViewerFlowControlEndMaster(viewer,&message_count);CHKERRQ(ierr);
1394   } else {
1395     ierr = PetscViewerFlowControlStepWorker(viewer,rank,&message_count);CHKERRQ(ierr);
1396     ierr = MPI_Send(&nz,1,MPIU_INT,0,tag,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1397     ierr = MPIULong_Send(column_indices,nz,MPIU_INT,0,tag,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1398     ierr = PetscViewerFlowControlEndWorker(viewer,&message_count);CHKERRQ(ierr);
1399   }
1400   ierr = PetscFree(column_indices);CHKERRQ(ierr);
1401 
1402   /* load up the local column values */
1403   ierr = PetscMalloc((nzmax+1)*sizeof(PetscScalar),&column_values);CHKERRQ(ierr);
1404   cnt  = 0;
1405   for (i=0; i<mat->rmap->n; i++) {
1406     for (j=B->i[i]; j<B->i[i+1]; j++) {
1407       if (garray[B->j[j]] > cstart) break;
1408       column_values[cnt++] = B->a[j];
1409     }
1410     for (k=A->i[i]; k<A->i[i+1]; k++) column_values[cnt++] = A->a[k];
1411     for (; j<B->i[i+1]; j++) column_values[cnt++] = B->a[j];
1412   }
1413   if (cnt != A->nz + B->nz) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_PLIB,"Internal PETSc error: cnt = %D nz = %D",cnt,A->nz+B->nz);
1414 
1415   /* store the column values to the file */
1416   ierr = PetscViewerFlowControlStart(viewer,&message_count,&flowcontrolcount);CHKERRQ(ierr);
1417   if (!rank) {
1418     MPI_Status status;
1419     ierr = PetscBinaryWrite(fd,column_values,nz,PETSC_SCALAR,PETSC_TRUE);CHKERRQ(ierr);
1420     for (i=1; i<size; i++) {
1421       ierr = PetscViewerFlowControlStepMaster(viewer,i,&message_count,flowcontrolcount);CHKERRQ(ierr);
1422       ierr = MPI_Recv(&rnz,1,MPIU_INT,i,tag,PetscObjectComm((PetscObject)mat),&status);CHKERRQ(ierr);
1423       if (rnz > nzmax) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_LIB,"Internal PETSc error: nz = %D nzmax = %D",nz,nzmax);
1424       ierr = MPIULong_Recv(column_values,rnz,MPIU_SCALAR,i,tag,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1425       ierr = PetscBinaryWrite(fd,column_values,rnz,PETSC_SCALAR,PETSC_TRUE);CHKERRQ(ierr);
1426     }
1427     ierr = PetscViewerFlowControlEndMaster(viewer,&message_count);CHKERRQ(ierr);
1428   } else {
1429     ierr = PetscViewerFlowControlStepWorker(viewer,rank,&message_count);CHKERRQ(ierr);
1430     ierr = MPI_Send(&nz,1,MPIU_INT,0,tag,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1431     ierr = MPIULong_Send(column_values,nz,MPIU_SCALAR,0,tag,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1432     ierr = PetscViewerFlowControlEndWorker(viewer,&message_count);CHKERRQ(ierr);
1433   }
1434   ierr = PetscFree(column_values);CHKERRQ(ierr);
1435 
1436   ierr = PetscViewerBinaryGetInfoPointer(viewer,&file);CHKERRQ(ierr);
1437   if (file) fprintf(file,"-matload_block_size %d\n",(int)mat->rmap->bs);
1438   PetscFunctionReturn(0);
1439 }
1440 
1441 #include <petscdraw.h>
1442 #undef __FUNCT__
1443 #define __FUNCT__ "MatView_MPIAIJ_ASCIIorDraworSocket"
1444 PetscErrorCode MatView_MPIAIJ_ASCIIorDraworSocket(Mat mat,PetscViewer viewer)
1445 {
1446   Mat_MPIAIJ        *aij = (Mat_MPIAIJ*)mat->data;
1447   PetscErrorCode    ierr;
1448   PetscMPIInt       rank = aij->rank,size = aij->size;
1449   PetscBool         isdraw,iascii,isbinary;
1450   PetscViewer       sviewer;
1451   PetscViewerFormat format;
1452 
1453   PetscFunctionBegin;
1454   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERDRAW,&isdraw);CHKERRQ(ierr);
1455   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERASCII,&iascii);CHKERRQ(ierr);
1456   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERBINARY,&isbinary);CHKERRQ(ierr);
1457   if (iascii) {
1458     ierr = PetscViewerGetFormat(viewer,&format);CHKERRQ(ierr);
1459     if (format == PETSC_VIEWER_ASCII_INFO_DETAIL) {
1460       MatInfo   info;
1461       PetscBool inodes;
1462 
1463       ierr = MPI_Comm_rank(PetscObjectComm((PetscObject)mat),&rank);CHKERRQ(ierr);
1464       ierr = MatGetInfo(mat,MAT_LOCAL,&info);CHKERRQ(ierr);
1465       ierr = MatInodeGetInodeSizes(aij->A,NULL,(PetscInt**)&inodes,NULL);CHKERRQ(ierr);
1466       ierr = PetscViewerASCIISynchronizedAllow(viewer,PETSC_TRUE);CHKERRQ(ierr);
1467       if (!inodes) {
1468         ierr = PetscViewerASCIISynchronizedPrintf(viewer,"[%d] Local rows %D nz %D nz alloced %D mem %D, not using I-node routines\n",
1469                                                   rank,mat->rmap->n,(PetscInt)info.nz_used,(PetscInt)info.nz_allocated,(PetscInt)info.memory);CHKERRQ(ierr);
1470       } else {
1471         ierr = PetscViewerASCIISynchronizedPrintf(viewer,"[%d] Local rows %D nz %D nz alloced %D mem %D, using I-node routines\n",
1472                                                   rank,mat->rmap->n,(PetscInt)info.nz_used,(PetscInt)info.nz_allocated,(PetscInt)info.memory);CHKERRQ(ierr);
1473       }
1474       ierr = MatGetInfo(aij->A,MAT_LOCAL,&info);CHKERRQ(ierr);
1475       ierr = PetscViewerASCIISynchronizedPrintf(viewer,"[%d] on-diagonal part: nz %D \n",rank,(PetscInt)info.nz_used);CHKERRQ(ierr);
1476       ierr = MatGetInfo(aij->B,MAT_LOCAL,&info);CHKERRQ(ierr);
1477       ierr = PetscViewerASCIISynchronizedPrintf(viewer,"[%d] off-diagonal part: nz %D \n",rank,(PetscInt)info.nz_used);CHKERRQ(ierr);
1478       ierr = PetscViewerFlush(viewer);CHKERRQ(ierr);
1479       ierr = PetscViewerASCIISynchronizedAllow(viewer,PETSC_FALSE);CHKERRQ(ierr);
1480       ierr = PetscViewerASCIIPrintf(viewer,"Information on VecScatter used in matrix-vector product: \n");CHKERRQ(ierr);
1481       ierr = VecScatterView(aij->Mvctx,viewer);CHKERRQ(ierr);
1482       PetscFunctionReturn(0);
1483     } else if (format == PETSC_VIEWER_ASCII_INFO) {
1484       PetscInt inodecount,inodelimit,*inodes;
1485       ierr = MatInodeGetInodeSizes(aij->A,&inodecount,&inodes,&inodelimit);CHKERRQ(ierr);
1486       if (inodes) {
1487         ierr = PetscViewerASCIIPrintf(viewer,"using I-node (on process 0) routines: found %D nodes, limit used is %D\n",inodecount,inodelimit);CHKERRQ(ierr);
1488       } else {
1489         ierr = PetscViewerASCIIPrintf(viewer,"not using I-node (on process 0) routines\n");CHKERRQ(ierr);
1490       }
1491       PetscFunctionReturn(0);
1492     } else if (format == PETSC_VIEWER_ASCII_FACTOR_INFO) {
1493       PetscFunctionReturn(0);
1494     }
1495   } else if (isbinary) {
1496     if (size == 1) {
1497       ierr = PetscObjectSetName((PetscObject)aij->A,((PetscObject)mat)->name);CHKERRQ(ierr);
1498       ierr = MatView(aij->A,viewer);CHKERRQ(ierr);
1499     } else {
1500       ierr = MatView_MPIAIJ_Binary(mat,viewer);CHKERRQ(ierr);
1501     }
1502     PetscFunctionReturn(0);
1503   } else if (isdraw) {
1504     PetscDraw draw;
1505     PetscBool isnull;
1506     ierr = PetscViewerDrawGetDraw(viewer,0,&draw);CHKERRQ(ierr);
1507     ierr = PetscDrawIsNull(draw,&isnull);CHKERRQ(ierr); if (isnull) PetscFunctionReturn(0);
1508   }
1509 
1510   if (size == 1) {
1511     ierr = PetscObjectSetName((PetscObject)aij->A,((PetscObject)mat)->name);CHKERRQ(ierr);
1512     ierr = MatView(aij->A,viewer);CHKERRQ(ierr);
1513   } else {
1514     /* assemble the entire matrix onto first processor. */
1515     Mat        A;
1516     Mat_SeqAIJ *Aloc;
1517     PetscInt   M = mat->rmap->N,N = mat->cmap->N,m,*ai,*aj,row,*cols,i,*ct;
1518     MatScalar  *a;
1519 
1520     if (mat->rmap->N > 1024) {
1521       PetscBool flg = PETSC_FALSE;
1522 
1523       ierr = PetscOptionsGetBool(((PetscObject) mat)->prefix, "-mat_ascii_output_large", &flg,NULL);CHKERRQ(ierr);
1524       if (!flg) SETERRQ(PetscObjectComm((PetscObject)mat),PETSC_ERR_ARG_OUTOFRANGE,"ASCII matrix output not allowed for matrices with more than 1024 rows, use binary format instead.\nYou can override this restriction using -mat_ascii_output_large.");
1525     }
1526 
1527     ierr = MatCreate(PetscObjectComm((PetscObject)mat),&A);CHKERRQ(ierr);
1528     if (!rank) {
1529       ierr = MatSetSizes(A,M,N,M,N);CHKERRQ(ierr);
1530     } else {
1531       ierr = MatSetSizes(A,0,0,M,N);CHKERRQ(ierr);
1532     }
1533     /* This is just a temporary matrix, so explicitly using MATMPIAIJ is probably best */
1534     ierr = MatSetType(A,MATMPIAIJ);CHKERRQ(ierr);
1535     ierr = MatMPIAIJSetPreallocation(A,0,NULL,0,NULL);CHKERRQ(ierr);
1536     ierr = MatSetOption(A,MAT_NEW_NONZERO_LOCATION_ERR,PETSC_FALSE);CHKERRQ(ierr);
1537     ierr = PetscLogObjectParent(mat,A);CHKERRQ(ierr);
1538 
1539     /* copy over the A part */
1540     Aloc = (Mat_SeqAIJ*)aij->A->data;
1541     m    = aij->A->rmap->n; ai = Aloc->i; aj = Aloc->j; a = Aloc->a;
1542     row  = mat->rmap->rstart;
1543     for (i=0; i<ai[m]; i++) aj[i] += mat->cmap->rstart;
1544     for (i=0; i<m; i++) {
1545       ierr = MatSetValues(A,1,&row,ai[i+1]-ai[i],aj,a,INSERT_VALUES);CHKERRQ(ierr);
1546       row++;
1547       a += ai[i+1]-ai[i]; aj += ai[i+1]-ai[i];
1548     }
1549     aj = Aloc->j;
1550     for (i=0; i<ai[m]; i++) aj[i] -= mat->cmap->rstart;
1551 
1552     /* copy over the B part */
1553     Aloc = (Mat_SeqAIJ*)aij->B->data;
1554     m    = aij->B->rmap->n;  ai = Aloc->i; aj = Aloc->j; a = Aloc->a;
1555     row  = mat->rmap->rstart;
1556     ierr = PetscMalloc((ai[m]+1)*sizeof(PetscInt),&cols);CHKERRQ(ierr);
1557     ct   = cols;
1558     for (i=0; i<ai[m]; i++) cols[i] = aij->garray[aj[i]];
1559     for (i=0; i<m; i++) {
1560       ierr = MatSetValues(A,1,&row,ai[i+1]-ai[i],cols,a,INSERT_VALUES);CHKERRQ(ierr);
1561       row++;
1562       a += ai[i+1]-ai[i]; cols += ai[i+1]-ai[i];
1563     }
1564     ierr = PetscFree(ct);CHKERRQ(ierr);
1565     ierr = MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
1566     ierr = MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
1567     /*
1568        Everyone has to call to draw the matrix since the graphics waits are
1569        synchronized across all processors that share the PetscDraw object
1570     */
1571     ierr = PetscViewerGetSingleton(viewer,&sviewer);CHKERRQ(ierr);
1572     if (!rank) {
1573       ierr = PetscObjectSetName((PetscObject)((Mat_MPIAIJ*)(A->data))->A,((PetscObject)mat)->name);CHKERRQ(ierr);
1574       /* Set the type name to MATMPIAIJ so that the correct type can be printed out by PetscObjectPrintClassNamePrefixType() in MatView_SeqAIJ_ASCII()*/
1575       PetscStrcpy(((PetscObject)((Mat_MPIAIJ*)(A->data))->A)->type_name,MATMPIAIJ);
1576       ierr = MatView(((Mat_MPIAIJ*)(A->data))->A,sviewer);CHKERRQ(ierr);
1577     }
1578     ierr = PetscViewerRestoreSingleton(viewer,&sviewer);CHKERRQ(ierr);
1579     ierr = MatDestroy(&A);CHKERRQ(ierr);
1580   }
1581   PetscFunctionReturn(0);
1582 }
1583 
1584 #undef __FUNCT__
1585 #define __FUNCT__ "MatView_MPIAIJ"
1586 PetscErrorCode MatView_MPIAIJ(Mat mat,PetscViewer viewer)
1587 {
1588   PetscErrorCode ierr;
1589   PetscBool      iascii,isdraw,issocket,isbinary;
1590 
1591   PetscFunctionBegin;
1592   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERASCII,&iascii);CHKERRQ(ierr);
1593   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERDRAW,&isdraw);CHKERRQ(ierr);
1594   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERBINARY,&isbinary);CHKERRQ(ierr);
1595   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERSOCKET,&issocket);CHKERRQ(ierr);
1596   if (iascii || isdraw || isbinary || issocket) {
1597     ierr = MatView_MPIAIJ_ASCIIorDraworSocket(mat,viewer);CHKERRQ(ierr);
1598   }
1599   PetscFunctionReturn(0);
1600 }
1601 
1602 #undef __FUNCT__
1603 #define __FUNCT__ "MatSOR_MPIAIJ"
1604 PetscErrorCode MatSOR_MPIAIJ(Mat matin,Vec bb,PetscReal omega,MatSORType flag,PetscReal fshift,PetscInt its,PetscInt lits,Vec xx)
1605 {
1606   Mat_MPIAIJ     *mat = (Mat_MPIAIJ*)matin->data;
1607   PetscErrorCode ierr;
1608   Vec            bb1 = 0;
1609   PetscBool      hasop;
1610 
1611   PetscFunctionBegin;
1612   if (flag == SOR_APPLY_UPPER) {
1613     ierr = (*mat->A->ops->sor)(mat->A,bb,omega,flag,fshift,lits,1,xx);CHKERRQ(ierr);
1614     PetscFunctionReturn(0);
1615   }
1616 
1617   if (its > 1 || ~flag & SOR_ZERO_INITIAL_GUESS || flag & SOR_EISENSTAT) {
1618     ierr = VecDuplicate(bb,&bb1);CHKERRQ(ierr);
1619   }
1620 
1621   if ((flag & SOR_LOCAL_SYMMETRIC_SWEEP) == SOR_LOCAL_SYMMETRIC_SWEEP) {
1622     if (flag & SOR_ZERO_INITIAL_GUESS) {
1623       ierr = (*mat->A->ops->sor)(mat->A,bb,omega,flag,fshift,lits,1,xx);CHKERRQ(ierr);
1624       its--;
1625     }
1626 
1627     while (its--) {
1628       ierr = VecScatterBegin(mat->Mvctx,xx,mat->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1629       ierr = VecScatterEnd(mat->Mvctx,xx,mat->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1630 
1631       /* update rhs: bb1 = bb - B*x */
1632       ierr = VecScale(mat->lvec,-1.0);CHKERRQ(ierr);
1633       ierr = (*mat->B->ops->multadd)(mat->B,mat->lvec,bb,bb1);CHKERRQ(ierr);
1634 
1635       /* local sweep */
1636       ierr = (*mat->A->ops->sor)(mat->A,bb1,omega,SOR_SYMMETRIC_SWEEP,fshift,lits,1,xx);CHKERRQ(ierr);
1637     }
1638   } else if (flag & SOR_LOCAL_FORWARD_SWEEP) {
1639     if (flag & SOR_ZERO_INITIAL_GUESS) {
1640       ierr = (*mat->A->ops->sor)(mat->A,bb,omega,flag,fshift,lits,1,xx);CHKERRQ(ierr);
1641       its--;
1642     }
1643     while (its--) {
1644       ierr = VecScatterBegin(mat->Mvctx,xx,mat->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1645       ierr = VecScatterEnd(mat->Mvctx,xx,mat->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1646 
1647       /* update rhs: bb1 = bb - B*x */
1648       ierr = VecScale(mat->lvec,-1.0);CHKERRQ(ierr);
1649       ierr = (*mat->B->ops->multadd)(mat->B,mat->lvec,bb,bb1);CHKERRQ(ierr);
1650 
1651       /* local sweep */
1652       ierr = (*mat->A->ops->sor)(mat->A,bb1,omega,SOR_FORWARD_SWEEP,fshift,lits,1,xx);CHKERRQ(ierr);
1653     }
1654   } else if (flag & SOR_LOCAL_BACKWARD_SWEEP) {
1655     if (flag & SOR_ZERO_INITIAL_GUESS) {
1656       ierr = (*mat->A->ops->sor)(mat->A,bb,omega,flag,fshift,lits,1,xx);CHKERRQ(ierr);
1657       its--;
1658     }
1659     while (its--) {
1660       ierr = VecScatterBegin(mat->Mvctx,xx,mat->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1661       ierr = VecScatterEnd(mat->Mvctx,xx,mat->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1662 
1663       /* update rhs: bb1 = bb - B*x */
1664       ierr = VecScale(mat->lvec,-1.0);CHKERRQ(ierr);
1665       ierr = (*mat->B->ops->multadd)(mat->B,mat->lvec,bb,bb1);CHKERRQ(ierr);
1666 
1667       /* local sweep */
1668       ierr = (*mat->A->ops->sor)(mat->A,bb1,omega,SOR_BACKWARD_SWEEP,fshift,lits,1,xx);CHKERRQ(ierr);
1669     }
1670   } else if (flag & SOR_EISENSTAT) {
1671     Vec xx1;
1672 
1673     ierr = VecDuplicate(bb,&xx1);CHKERRQ(ierr);
1674     ierr = (*mat->A->ops->sor)(mat->A,bb,omega,(MatSORType)(SOR_ZERO_INITIAL_GUESS | SOR_LOCAL_BACKWARD_SWEEP),fshift,lits,1,xx);CHKERRQ(ierr);
1675 
1676     ierr = VecScatterBegin(mat->Mvctx,xx,mat->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1677     ierr = VecScatterEnd(mat->Mvctx,xx,mat->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1678     if (!mat->diag) {
1679       ierr = MatGetVecs(matin,&mat->diag,NULL);CHKERRQ(ierr);
1680       ierr = MatGetDiagonal(matin,mat->diag);CHKERRQ(ierr);
1681     }
1682     ierr = MatHasOperation(matin,MATOP_MULT_DIAGONAL_BLOCK,&hasop);CHKERRQ(ierr);
1683     if (hasop) {
1684       ierr = MatMultDiagonalBlock(matin,xx,bb1);CHKERRQ(ierr);
1685     } else {
1686       ierr = VecPointwiseMult(bb1,mat->diag,xx);CHKERRQ(ierr);
1687     }
1688     ierr = VecAYPX(bb1,(omega-2.0)/omega,bb);CHKERRQ(ierr);
1689 
1690     ierr = MatMultAdd(mat->B,mat->lvec,bb1,bb1);CHKERRQ(ierr);
1691 
1692     /* local sweep */
1693     ierr = (*mat->A->ops->sor)(mat->A,bb1,omega,(MatSORType)(SOR_ZERO_INITIAL_GUESS | SOR_LOCAL_FORWARD_SWEEP),fshift,lits,1,xx1);CHKERRQ(ierr);
1694     ierr = VecAXPY(xx,1.0,xx1);CHKERRQ(ierr);
1695     ierr = VecDestroy(&xx1);CHKERRQ(ierr);
1696   } else SETERRQ(PetscObjectComm((PetscObject)matin),PETSC_ERR_SUP,"Parallel SOR not supported");
1697 
1698   ierr = VecDestroy(&bb1);CHKERRQ(ierr);
1699   PetscFunctionReturn(0);
1700 }
1701 
1702 #undef __FUNCT__
1703 #define __FUNCT__ "MatPermute_MPIAIJ"
1704 PetscErrorCode MatPermute_MPIAIJ(Mat A,IS rowp,IS colp,Mat *B)
1705 {
1706   Mat            aA,aB,Aperm;
1707   const PetscInt *rwant,*cwant,*gcols,*ai,*bi,*aj,*bj;
1708   PetscScalar    *aa,*ba;
1709   PetscInt       i,j,m,n,ng,anz,bnz,*dnnz,*onnz,*tdnnz,*tonnz,*rdest,*cdest,*work,*gcdest;
1710   PetscSF        rowsf,sf;
1711   IS             parcolp = NULL;
1712   PetscBool      done;
1713   PetscErrorCode ierr;
1714 
1715   PetscFunctionBegin;
1716   ierr = MatGetLocalSize(A,&m,&n);CHKERRQ(ierr);
1717   ierr = ISGetIndices(rowp,&rwant);CHKERRQ(ierr);
1718   ierr = ISGetIndices(colp,&cwant);CHKERRQ(ierr);
1719   ierr = PetscMalloc3(PetscMax(m,n),PetscInt,&work,m,PetscInt,&rdest,n,PetscInt,&cdest);CHKERRQ(ierr);
1720 
1721   /* Invert row permutation to find out where my rows should go */
1722   ierr = PetscSFCreate(PetscObjectComm((PetscObject)A),&rowsf);CHKERRQ(ierr);
1723   ierr = PetscSFSetGraphLayout(rowsf,A->rmap,A->rmap->n,NULL,PETSC_OWN_POINTER,rwant);CHKERRQ(ierr);
1724   ierr = PetscSFSetFromOptions(rowsf);CHKERRQ(ierr);
1725   for (i=0; i<m; i++) work[i] = A->rmap->rstart + i;
1726   ierr = PetscSFReduceBegin(rowsf,MPIU_INT,work,rdest,MPIU_REPLACE);CHKERRQ(ierr);
1727   ierr = PetscSFReduceEnd(rowsf,MPIU_INT,work,rdest,MPIU_REPLACE);CHKERRQ(ierr);
1728 
1729   /* Invert column permutation to find out where my columns should go */
1730   ierr = PetscSFCreate(PetscObjectComm((PetscObject)A),&sf);CHKERRQ(ierr);
1731   ierr = PetscSFSetGraphLayout(sf,A->cmap,A->cmap->n,NULL,PETSC_OWN_POINTER,cwant);CHKERRQ(ierr);
1732   ierr = PetscSFSetFromOptions(sf);CHKERRQ(ierr);
1733   for (i=0; i<n; i++) work[i] = A->cmap->rstart + i;
1734   ierr = PetscSFReduceBegin(sf,MPIU_INT,work,cdest,MPIU_REPLACE);CHKERRQ(ierr);
1735   ierr = PetscSFReduceEnd(sf,MPIU_INT,work,cdest,MPIU_REPLACE);CHKERRQ(ierr);
1736   ierr = PetscSFDestroy(&sf);CHKERRQ(ierr);
1737 
1738   ierr = ISRestoreIndices(rowp,&rwant);CHKERRQ(ierr);
1739   ierr = ISRestoreIndices(colp,&cwant);CHKERRQ(ierr);
1740   ierr = MatMPIAIJGetSeqAIJ(A,&aA,&aB,&gcols);CHKERRQ(ierr);
1741 
1742   /* Find out where my gcols should go */
1743   ierr = MatGetSize(aB,NULL,&ng);CHKERRQ(ierr);
1744   ierr = PetscMalloc(ng*sizeof(PetscInt),&gcdest);CHKERRQ(ierr);
1745   ierr = PetscSFCreate(PetscObjectComm((PetscObject)A),&sf);CHKERRQ(ierr);
1746   ierr = PetscSFSetGraphLayout(sf,A->cmap,ng,NULL,PETSC_OWN_POINTER,gcols);CHKERRQ(ierr);
1747   ierr = PetscSFSetFromOptions(sf);CHKERRQ(ierr);
1748   ierr = PetscSFBcastBegin(sf,MPIU_INT,cdest,gcdest);CHKERRQ(ierr);
1749   ierr = PetscSFBcastEnd(sf,MPIU_INT,cdest,gcdest);CHKERRQ(ierr);
1750   ierr = PetscSFDestroy(&sf);CHKERRQ(ierr);
1751 
1752   ierr = PetscMalloc4(m,PetscInt,&dnnz,m,PetscInt,&onnz,m,PetscInt,&tdnnz,m,PetscInt,&tonnz);CHKERRQ(ierr);
1753   ierr = PetscMemzero(dnnz,m*sizeof(PetscInt));CHKERRQ(ierr);
1754   ierr = PetscMemzero(onnz,m*sizeof(PetscInt));CHKERRQ(ierr);
1755   ierr = MatGetRowIJ(aA,0,PETSC_FALSE,PETSC_FALSE,&anz,&ai,&aj,&done);CHKERRQ(ierr);
1756   ierr = MatGetRowIJ(aB,0,PETSC_FALSE,PETSC_FALSE,&bnz,&bi,&bj,&done);CHKERRQ(ierr);
1757   for (i=0; i<m; i++) {
1758     PetscInt row = rdest[i],rowner;
1759     ierr = PetscLayoutFindOwner(A->rmap,row,&rowner);CHKERRQ(ierr);
1760     for (j=ai[i]; j<ai[i+1]; j++) {
1761       PetscInt cowner,col = cdest[aj[j]];
1762       ierr = PetscLayoutFindOwner(A->cmap,col,&cowner);CHKERRQ(ierr); /* Could build an index for the columns to eliminate this search */
1763       if (rowner == cowner) dnnz[i]++;
1764       else onnz[i]++;
1765     }
1766     for (j=bi[i]; j<bi[i+1]; j++) {
1767       PetscInt cowner,col = gcdest[bj[j]];
1768       ierr = PetscLayoutFindOwner(A->cmap,col,&cowner);CHKERRQ(ierr);
1769       if (rowner == cowner) dnnz[i]++;
1770       else onnz[i]++;
1771     }
1772   }
1773   ierr = PetscMemzero(tdnnz,m*sizeof(PetscInt));CHKERRQ(ierr);
1774   ierr = PetscMemzero(tonnz,m*sizeof(PetscInt));CHKERRQ(ierr);
1775   ierr = PetscSFBcastBegin(rowsf,MPIU_INT,dnnz,tdnnz);CHKERRQ(ierr);
1776   ierr = PetscSFBcastEnd(rowsf,MPIU_INT,dnnz,tdnnz);CHKERRQ(ierr);
1777   ierr = PetscSFBcastBegin(rowsf,MPIU_INT,onnz,tonnz);CHKERRQ(ierr);
1778   ierr = PetscSFBcastEnd(rowsf,MPIU_INT,onnz,tonnz);CHKERRQ(ierr);
1779   ierr = PetscSFDestroy(&rowsf);CHKERRQ(ierr);
1780 
1781   ierr = MatCreateAIJ(PetscObjectComm((PetscObject)A),A->rmap->n,A->cmap->n,A->rmap->N,A->cmap->N,0,tdnnz,0,tonnz,&Aperm);CHKERRQ(ierr);
1782   ierr = MatSeqAIJGetArray(aA,&aa);CHKERRQ(ierr);
1783   ierr = MatSeqAIJGetArray(aB,&ba);CHKERRQ(ierr);
1784   for (i=0; i<m; i++) {
1785     PetscInt *acols = dnnz,*bcols = onnz; /* Repurpose now-unneeded arrays */
1786     PetscInt rowlen;
1787     rowlen = ai[i+1] - ai[i];
1788     for (j=0; j<rowlen; j++) acols[j] = cdest[aj[ai[i]+j]];
1789     ierr   = MatSetValues(Aperm,1,&rdest[i],rowlen,acols,aa+ai[i],INSERT_VALUES);CHKERRQ(ierr);
1790     rowlen = bi[i+1] - bi[i];
1791     for (j=0; j<rowlen; j++) bcols[j] = gcdest[bj[bi[i]+j]];
1792     ierr = MatSetValues(Aperm,1,&rdest[i],rowlen,bcols,ba+bi[i],INSERT_VALUES);CHKERRQ(ierr);
1793   }
1794   ierr = MatAssemblyBegin(Aperm,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
1795   ierr = MatAssemblyEnd(Aperm,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
1796   ierr = MatRestoreRowIJ(aA,0,PETSC_FALSE,PETSC_FALSE,&anz,&ai,&aj,&done);CHKERRQ(ierr);
1797   ierr = MatRestoreRowIJ(aB,0,PETSC_FALSE,PETSC_FALSE,&bnz,&bi,&bj,&done);CHKERRQ(ierr);
1798   ierr = MatSeqAIJRestoreArray(aA,&aa);CHKERRQ(ierr);
1799   ierr = MatSeqAIJRestoreArray(aB,&ba);CHKERRQ(ierr);
1800   ierr = PetscFree4(dnnz,onnz,tdnnz,tonnz);CHKERRQ(ierr);
1801   ierr = PetscFree3(work,rdest,cdest);CHKERRQ(ierr);
1802   ierr = PetscFree(gcdest);CHKERRQ(ierr);
1803   if (parcolp) {ierr = ISDestroy(&colp);CHKERRQ(ierr);}
1804   *B = Aperm;
1805   PetscFunctionReturn(0);
1806 }
1807 
1808 #undef __FUNCT__
1809 #define __FUNCT__ "MatGetInfo_MPIAIJ"
1810 PetscErrorCode MatGetInfo_MPIAIJ(Mat matin,MatInfoType flag,MatInfo *info)
1811 {
1812   Mat_MPIAIJ     *mat = (Mat_MPIAIJ*)matin->data;
1813   Mat            A    = mat->A,B = mat->B;
1814   PetscErrorCode ierr;
1815   PetscReal      isend[5],irecv[5];
1816 
1817   PetscFunctionBegin;
1818   info->block_size = 1.0;
1819   ierr             = MatGetInfo(A,MAT_LOCAL,info);CHKERRQ(ierr);
1820 
1821   isend[0] = info->nz_used; isend[1] = info->nz_allocated; isend[2] = info->nz_unneeded;
1822   isend[3] = info->memory;  isend[4] = info->mallocs;
1823 
1824   ierr = MatGetInfo(B,MAT_LOCAL,info);CHKERRQ(ierr);
1825 
1826   isend[0] += info->nz_used; isend[1] += info->nz_allocated; isend[2] += info->nz_unneeded;
1827   isend[3] += info->memory;  isend[4] += info->mallocs;
1828   if (flag == MAT_LOCAL) {
1829     info->nz_used      = isend[0];
1830     info->nz_allocated = isend[1];
1831     info->nz_unneeded  = isend[2];
1832     info->memory       = isend[3];
1833     info->mallocs      = isend[4];
1834   } else if (flag == MAT_GLOBAL_MAX) {
1835     ierr = MPI_Allreduce(isend,irecv,5,MPIU_REAL,MPIU_MAX,PetscObjectComm((PetscObject)matin));CHKERRQ(ierr);
1836 
1837     info->nz_used      = irecv[0];
1838     info->nz_allocated = irecv[1];
1839     info->nz_unneeded  = irecv[2];
1840     info->memory       = irecv[3];
1841     info->mallocs      = irecv[4];
1842   } else if (flag == MAT_GLOBAL_SUM) {
1843     ierr = MPI_Allreduce(isend,irecv,5,MPIU_REAL,MPIU_SUM,PetscObjectComm((PetscObject)matin));CHKERRQ(ierr);
1844 
1845     info->nz_used      = irecv[0];
1846     info->nz_allocated = irecv[1];
1847     info->nz_unneeded  = irecv[2];
1848     info->memory       = irecv[3];
1849     info->mallocs      = irecv[4];
1850   }
1851   info->fill_ratio_given  = 0; /* no parallel LU/ILU/Cholesky */
1852   info->fill_ratio_needed = 0;
1853   info->factor_mallocs    = 0;
1854   PetscFunctionReturn(0);
1855 }
1856 
1857 #undef __FUNCT__
1858 #define __FUNCT__ "MatSetOption_MPIAIJ"
1859 PetscErrorCode MatSetOption_MPIAIJ(Mat A,MatOption op,PetscBool flg)
1860 {
1861   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
1862   PetscErrorCode ierr;
1863 
1864   PetscFunctionBegin;
1865   switch (op) {
1866   case MAT_NEW_NONZERO_LOCATIONS:
1867   case MAT_NEW_NONZERO_ALLOCATION_ERR:
1868   case MAT_UNUSED_NONZERO_LOCATION_ERR:
1869   case MAT_KEEP_NONZERO_PATTERN:
1870   case MAT_NEW_NONZERO_LOCATION_ERR:
1871   case MAT_USE_INODES:
1872   case MAT_IGNORE_ZERO_ENTRIES:
1873     MatCheckPreallocated(A,1);
1874     ierr = MatSetOption(a->A,op,flg);CHKERRQ(ierr);
1875     ierr = MatSetOption(a->B,op,flg);CHKERRQ(ierr);
1876     break;
1877   case MAT_ROW_ORIENTED:
1878     a->roworiented = flg;
1879 
1880     ierr = MatSetOption(a->A,op,flg);CHKERRQ(ierr);
1881     ierr = MatSetOption(a->B,op,flg);CHKERRQ(ierr);
1882     break;
1883   case MAT_NEW_DIAGONALS:
1884     ierr = PetscInfo1(A,"Option %s ignored\n",MatOptions[op]);CHKERRQ(ierr);
1885     break;
1886   case MAT_IGNORE_OFF_PROC_ENTRIES:
1887     a->donotstash = flg;
1888     break;
1889   case MAT_SPD:
1890     A->spd_set = PETSC_TRUE;
1891     A->spd     = flg;
1892     if (flg) {
1893       A->symmetric                  = PETSC_TRUE;
1894       A->structurally_symmetric     = PETSC_TRUE;
1895       A->symmetric_set              = PETSC_TRUE;
1896       A->structurally_symmetric_set = PETSC_TRUE;
1897     }
1898     break;
1899   case MAT_SYMMETRIC:
1900     ierr = MatSetOption(a->A,op,flg);CHKERRQ(ierr);
1901     break;
1902   case MAT_STRUCTURALLY_SYMMETRIC:
1903     ierr = MatSetOption(a->A,op,flg);CHKERRQ(ierr);
1904     break;
1905   case MAT_HERMITIAN:
1906     ierr = MatSetOption(a->A,op,flg);CHKERRQ(ierr);
1907     break;
1908   case MAT_SYMMETRY_ETERNAL:
1909     ierr = MatSetOption(a->A,op,flg);CHKERRQ(ierr);
1910     break;
1911   default:
1912     SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_SUP,"unknown option %d",op);
1913   }
1914   PetscFunctionReturn(0);
1915 }
1916 
1917 #undef __FUNCT__
1918 #define __FUNCT__ "MatGetRow_MPIAIJ"
1919 PetscErrorCode MatGetRow_MPIAIJ(Mat matin,PetscInt row,PetscInt *nz,PetscInt **idx,PetscScalar **v)
1920 {
1921   Mat_MPIAIJ     *mat = (Mat_MPIAIJ*)matin->data;
1922   PetscScalar    *vworkA,*vworkB,**pvA,**pvB,*v_p;
1923   PetscErrorCode ierr;
1924   PetscInt       i,*cworkA,*cworkB,**pcA,**pcB,cstart = matin->cmap->rstart;
1925   PetscInt       nztot,nzA,nzB,lrow,rstart = matin->rmap->rstart,rend = matin->rmap->rend;
1926   PetscInt       *cmap,*idx_p;
1927 
1928   PetscFunctionBegin;
1929   if (mat->getrowactive) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"Already active");
1930   mat->getrowactive = PETSC_TRUE;
1931 
1932   if (!mat->rowvalues && (idx || v)) {
1933     /*
1934         allocate enough space to hold information from the longest row.
1935     */
1936     Mat_SeqAIJ *Aa = (Mat_SeqAIJ*)mat->A->data,*Ba = (Mat_SeqAIJ*)mat->B->data;
1937     PetscInt   max = 1,tmp;
1938     for (i=0; i<matin->rmap->n; i++) {
1939       tmp = Aa->i[i+1] - Aa->i[i] + Ba->i[i+1] - Ba->i[i];
1940       if (max < tmp) max = tmp;
1941     }
1942     ierr = PetscMalloc2(max,PetscScalar,&mat->rowvalues,max,PetscInt,&mat->rowindices);CHKERRQ(ierr);
1943   }
1944 
1945   if (row < rstart || row >= rend) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Only local rows");
1946   lrow = row - rstart;
1947 
1948   pvA = &vworkA; pcA = &cworkA; pvB = &vworkB; pcB = &cworkB;
1949   if (!v)   {pvA = 0; pvB = 0;}
1950   if (!idx) {pcA = 0; if (!v) pcB = 0;}
1951   ierr  = (*mat->A->ops->getrow)(mat->A,lrow,&nzA,pcA,pvA);CHKERRQ(ierr);
1952   ierr  = (*mat->B->ops->getrow)(mat->B,lrow,&nzB,pcB,pvB);CHKERRQ(ierr);
1953   nztot = nzA + nzB;
1954 
1955   cmap = mat->garray;
1956   if (v  || idx) {
1957     if (nztot) {
1958       /* Sort by increasing column numbers, assuming A and B already sorted */
1959       PetscInt imark = -1;
1960       if (v) {
1961         *v = v_p = mat->rowvalues;
1962         for (i=0; i<nzB; i++) {
1963           if (cmap[cworkB[i]] < cstart) v_p[i] = vworkB[i];
1964           else break;
1965         }
1966         imark = i;
1967         for (i=0; i<nzA; i++)     v_p[imark+i] = vworkA[i];
1968         for (i=imark; i<nzB; i++) v_p[nzA+i]   = vworkB[i];
1969       }
1970       if (idx) {
1971         *idx = idx_p = mat->rowindices;
1972         if (imark > -1) {
1973           for (i=0; i<imark; i++) {
1974             idx_p[i] = cmap[cworkB[i]];
1975           }
1976         } else {
1977           for (i=0; i<nzB; i++) {
1978             if (cmap[cworkB[i]] < cstart) idx_p[i] = cmap[cworkB[i]];
1979             else break;
1980           }
1981           imark = i;
1982         }
1983         for (i=0; i<nzA; i++)     idx_p[imark+i] = cstart + cworkA[i];
1984         for (i=imark; i<nzB; i++) idx_p[nzA+i]   = cmap[cworkB[i]];
1985       }
1986     } else {
1987       if (idx) *idx = 0;
1988       if (v)   *v   = 0;
1989     }
1990   }
1991   *nz  = nztot;
1992   ierr = (*mat->A->ops->restorerow)(mat->A,lrow,&nzA,pcA,pvA);CHKERRQ(ierr);
1993   ierr = (*mat->B->ops->restorerow)(mat->B,lrow,&nzB,pcB,pvB);CHKERRQ(ierr);
1994   PetscFunctionReturn(0);
1995 }
1996 
1997 #undef __FUNCT__
1998 #define __FUNCT__ "MatRestoreRow_MPIAIJ"
1999 PetscErrorCode MatRestoreRow_MPIAIJ(Mat mat,PetscInt row,PetscInt *nz,PetscInt **idx,PetscScalar **v)
2000 {
2001   Mat_MPIAIJ *aij = (Mat_MPIAIJ*)mat->data;
2002 
2003   PetscFunctionBegin;
2004   if (!aij->getrowactive) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"MatGetRow() must be called first");
2005   aij->getrowactive = PETSC_FALSE;
2006   PetscFunctionReturn(0);
2007 }
2008 
2009 #undef __FUNCT__
2010 #define __FUNCT__ "MatNorm_MPIAIJ"
2011 PetscErrorCode MatNorm_MPIAIJ(Mat mat,NormType type,PetscReal *norm)
2012 {
2013   Mat_MPIAIJ     *aij  = (Mat_MPIAIJ*)mat->data;
2014   Mat_SeqAIJ     *amat = (Mat_SeqAIJ*)aij->A->data,*bmat = (Mat_SeqAIJ*)aij->B->data;
2015   PetscErrorCode ierr;
2016   PetscInt       i,j,cstart = mat->cmap->rstart;
2017   PetscReal      sum = 0.0;
2018   MatScalar      *v;
2019 
2020   PetscFunctionBegin;
2021   if (aij->size == 1) {
2022     ierr =  MatNorm(aij->A,type,norm);CHKERRQ(ierr);
2023   } else {
2024     if (type == NORM_FROBENIUS) {
2025       v = amat->a;
2026       for (i=0; i<amat->nz; i++) {
2027         sum += PetscRealPart(PetscConj(*v)*(*v)); v++;
2028       }
2029       v = bmat->a;
2030       for (i=0; i<bmat->nz; i++) {
2031         sum += PetscRealPart(PetscConj(*v)*(*v)); v++;
2032       }
2033       ierr  = MPI_Allreduce(&sum,norm,1,MPIU_REAL,MPIU_SUM,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
2034       *norm = PetscSqrtReal(*norm);
2035     } else if (type == NORM_1) { /* max column norm */
2036       PetscReal *tmp,*tmp2;
2037       PetscInt  *jj,*garray = aij->garray;
2038       ierr  = PetscMalloc((mat->cmap->N+1)*sizeof(PetscReal),&tmp);CHKERRQ(ierr);
2039       ierr  = PetscMalloc((mat->cmap->N+1)*sizeof(PetscReal),&tmp2);CHKERRQ(ierr);
2040       ierr  = PetscMemzero(tmp,mat->cmap->N*sizeof(PetscReal));CHKERRQ(ierr);
2041       *norm = 0.0;
2042       v     = amat->a; jj = amat->j;
2043       for (j=0; j<amat->nz; j++) {
2044         tmp[cstart + *jj++] += PetscAbsScalar(*v);  v++;
2045       }
2046       v = bmat->a; jj = bmat->j;
2047       for (j=0; j<bmat->nz; j++) {
2048         tmp[garray[*jj++]] += PetscAbsScalar(*v); v++;
2049       }
2050       ierr = MPI_Allreduce(tmp,tmp2,mat->cmap->N,MPIU_REAL,MPIU_SUM,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
2051       for (j=0; j<mat->cmap->N; j++) {
2052         if (tmp2[j] > *norm) *norm = tmp2[j];
2053       }
2054       ierr = PetscFree(tmp);CHKERRQ(ierr);
2055       ierr = PetscFree(tmp2);CHKERRQ(ierr);
2056     } else if (type == NORM_INFINITY) { /* max row norm */
2057       PetscReal ntemp = 0.0;
2058       for (j=0; j<aij->A->rmap->n; j++) {
2059         v   = amat->a + amat->i[j];
2060         sum = 0.0;
2061         for (i=0; i<amat->i[j+1]-amat->i[j]; i++) {
2062           sum += PetscAbsScalar(*v); v++;
2063         }
2064         v = bmat->a + bmat->i[j];
2065         for (i=0; i<bmat->i[j+1]-bmat->i[j]; i++) {
2066           sum += PetscAbsScalar(*v); v++;
2067         }
2068         if (sum > ntemp) ntemp = sum;
2069       }
2070       ierr = MPI_Allreduce(&ntemp,norm,1,MPIU_REAL,MPIU_MAX,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
2071     } else SETERRQ(PetscObjectComm((PetscObject)mat),PETSC_ERR_SUP,"No support for two norm");
2072   }
2073   PetscFunctionReturn(0);
2074 }
2075 
2076 #undef __FUNCT__
2077 #define __FUNCT__ "MatTranspose_MPIAIJ"
2078 PetscErrorCode MatTranspose_MPIAIJ(Mat A,MatReuse reuse,Mat *matout)
2079 {
2080   Mat_MPIAIJ     *a   = (Mat_MPIAIJ*)A->data;
2081   Mat_SeqAIJ     *Aloc=(Mat_SeqAIJ*)a->A->data,*Bloc=(Mat_SeqAIJ*)a->B->data;
2082   PetscErrorCode ierr;
2083   PetscInt       M      = A->rmap->N,N = A->cmap->N,ma,na,mb,nb,*ai,*aj,*bi,*bj,row,*cols,*cols_tmp,i;
2084   PetscInt       cstart = A->cmap->rstart,ncol;
2085   Mat            B;
2086   MatScalar      *array;
2087 
2088   PetscFunctionBegin;
2089   if (reuse == MAT_REUSE_MATRIX && A == *matout && M != N) SETERRQ(PetscObjectComm((PetscObject)A),PETSC_ERR_ARG_SIZ,"Square matrix only for in-place");
2090 
2091   ma = A->rmap->n; na = A->cmap->n; mb = a->B->rmap->n; nb = a->B->cmap->n;
2092   ai = Aloc->i; aj = Aloc->j;
2093   bi = Bloc->i; bj = Bloc->j;
2094   if (reuse == MAT_INITIAL_MATRIX || *matout == A) {
2095     PetscInt             *d_nnz,*g_nnz,*o_nnz;
2096     PetscSFNode          *oloc;
2097     PETSC_UNUSED PetscSF sf;
2098 
2099     ierr = PetscMalloc4(na,PetscInt,&d_nnz,na,PetscInt,&o_nnz,nb,PetscInt,&g_nnz,nb,PetscSFNode,&oloc);CHKERRQ(ierr);
2100     /* compute d_nnz for preallocation */
2101     ierr = PetscMemzero(d_nnz,na*sizeof(PetscInt));CHKERRQ(ierr);
2102     for (i=0; i<ai[ma]; i++) {
2103       d_nnz[aj[i]]++;
2104       aj[i] += cstart; /* global col index to be used by MatSetValues() */
2105     }
2106     /* compute local off-diagonal contributions */
2107     ierr = PetscMemzero(g_nnz,nb*sizeof(PetscInt));CHKERRQ(ierr);
2108     for (i=0; i<bi[ma]; i++) g_nnz[bj[i]]++;
2109     /* map those to global */
2110     ierr = PetscSFCreate(PetscObjectComm((PetscObject)A),&sf);CHKERRQ(ierr);
2111     ierr = PetscSFSetGraphLayout(sf,A->cmap,nb,NULL,PETSC_USE_POINTER,a->garray);CHKERRQ(ierr);
2112     ierr = PetscSFSetFromOptions(sf);CHKERRQ(ierr);
2113     ierr = PetscMemzero(o_nnz,na*sizeof(PetscInt));CHKERRQ(ierr);
2114     ierr = PetscSFReduceBegin(sf,MPIU_INT,g_nnz,o_nnz,MPIU_SUM);CHKERRQ(ierr);
2115     ierr = PetscSFReduceEnd(sf,MPIU_INT,g_nnz,o_nnz,MPIU_SUM);CHKERRQ(ierr);
2116     ierr = PetscSFDestroy(&sf);CHKERRQ(ierr);
2117 
2118     ierr = MatCreate(PetscObjectComm((PetscObject)A),&B);CHKERRQ(ierr);
2119     ierr = MatSetSizes(B,A->cmap->n,A->rmap->n,N,M);CHKERRQ(ierr);
2120     ierr = MatSetBlockSizes(B,A->cmap->bs,A->rmap->bs);CHKERRQ(ierr);
2121     ierr = MatSetType(B,((PetscObject)A)->type_name);CHKERRQ(ierr);
2122     ierr = MatMPIAIJSetPreallocation(B,0,d_nnz,0,o_nnz);CHKERRQ(ierr);
2123     ierr = PetscFree4(d_nnz,o_nnz,g_nnz,oloc);CHKERRQ(ierr);
2124   } else {
2125     B    = *matout;
2126     ierr = MatSetOption(B,MAT_NEW_NONZERO_ALLOCATION_ERR,PETSC_TRUE);CHKERRQ(ierr);
2127     for (i=0; i<ai[ma]; i++) aj[i] += cstart; /* global col index to be used by MatSetValues() */
2128   }
2129 
2130   /* copy over the A part */
2131   array = Aloc->a;
2132   row   = A->rmap->rstart;
2133   for (i=0; i<ma; i++) {
2134     ncol = ai[i+1]-ai[i];
2135     ierr = MatSetValues(B,ncol,aj,1,&row,array,INSERT_VALUES);CHKERRQ(ierr);
2136     row++;
2137     array += ncol; aj += ncol;
2138   }
2139   aj = Aloc->j;
2140   for (i=0; i<ai[ma]; i++) aj[i] -= cstart; /* resume local col index */
2141 
2142   /* copy over the B part */
2143   ierr  = PetscMalloc(bi[mb]*sizeof(PetscInt),&cols);CHKERRQ(ierr);
2144   ierr  = PetscMemzero(cols,bi[mb]*sizeof(PetscInt));CHKERRQ(ierr);
2145   array = Bloc->a;
2146   row   = A->rmap->rstart;
2147   for (i=0; i<bi[mb]; i++) cols[i] = a->garray[bj[i]];
2148   cols_tmp = cols;
2149   for (i=0; i<mb; i++) {
2150     ncol = bi[i+1]-bi[i];
2151     ierr = MatSetValues(B,ncol,cols_tmp,1,&row,array,INSERT_VALUES);CHKERRQ(ierr);
2152     row++;
2153     array += ncol; cols_tmp += ncol;
2154   }
2155   ierr = PetscFree(cols);CHKERRQ(ierr);
2156 
2157   ierr = MatAssemblyBegin(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
2158   ierr = MatAssemblyEnd(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
2159   if (reuse == MAT_INITIAL_MATRIX || *matout != A) {
2160     *matout = B;
2161   } else {
2162     ierr = MatHeaderMerge(A,B);CHKERRQ(ierr);
2163   }
2164   PetscFunctionReturn(0);
2165 }
2166 
2167 #undef __FUNCT__
2168 #define __FUNCT__ "MatDiagonalScale_MPIAIJ"
2169 PetscErrorCode MatDiagonalScale_MPIAIJ(Mat mat,Vec ll,Vec rr)
2170 {
2171   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
2172   Mat            a    = aij->A,b = aij->B;
2173   PetscErrorCode ierr;
2174   PetscInt       s1,s2,s3;
2175 
2176   PetscFunctionBegin;
2177   ierr = MatGetLocalSize(mat,&s2,&s3);CHKERRQ(ierr);
2178   if (rr) {
2179     ierr = VecGetLocalSize(rr,&s1);CHKERRQ(ierr);
2180     if (s1!=s3) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_SIZ,"right vector non-conforming local size");
2181     /* Overlap communication with computation. */
2182     ierr = VecScatterBegin(aij->Mvctx,rr,aij->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
2183   }
2184   if (ll) {
2185     ierr = VecGetLocalSize(ll,&s1);CHKERRQ(ierr);
2186     if (s1!=s2) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_SIZ,"left vector non-conforming local size");
2187     ierr = (*b->ops->diagonalscale)(b,ll,0);CHKERRQ(ierr);
2188   }
2189   /* scale  the diagonal block */
2190   ierr = (*a->ops->diagonalscale)(a,ll,rr);CHKERRQ(ierr);
2191 
2192   if (rr) {
2193     /* Do a scatter end and then right scale the off-diagonal block */
2194     ierr = VecScatterEnd(aij->Mvctx,rr,aij->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
2195     ierr = (*b->ops->diagonalscale)(b,0,aij->lvec);CHKERRQ(ierr);
2196   }
2197   PetscFunctionReturn(0);
2198 }
2199 
2200 #undef __FUNCT__
2201 #define __FUNCT__ "MatSetUnfactored_MPIAIJ"
2202 PetscErrorCode MatSetUnfactored_MPIAIJ(Mat A)
2203 {
2204   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
2205   PetscErrorCode ierr;
2206 
2207   PetscFunctionBegin;
2208   ierr = MatSetUnfactored(a->A);CHKERRQ(ierr);
2209   PetscFunctionReturn(0);
2210 }
2211 
2212 #undef __FUNCT__
2213 #define __FUNCT__ "MatEqual_MPIAIJ"
2214 PetscErrorCode MatEqual_MPIAIJ(Mat A,Mat B,PetscBool  *flag)
2215 {
2216   Mat_MPIAIJ     *matB = (Mat_MPIAIJ*)B->data,*matA = (Mat_MPIAIJ*)A->data;
2217   Mat            a,b,c,d;
2218   PetscBool      flg;
2219   PetscErrorCode ierr;
2220 
2221   PetscFunctionBegin;
2222   a = matA->A; b = matA->B;
2223   c = matB->A; d = matB->B;
2224 
2225   ierr = MatEqual(a,c,&flg);CHKERRQ(ierr);
2226   if (flg) {
2227     ierr = MatEqual(b,d,&flg);CHKERRQ(ierr);
2228   }
2229   ierr = MPI_Allreduce(&flg,flag,1,MPIU_BOOL,MPI_LAND,PetscObjectComm((PetscObject)A));CHKERRQ(ierr);
2230   PetscFunctionReturn(0);
2231 }
2232 
2233 #undef __FUNCT__
2234 #define __FUNCT__ "MatCopy_MPIAIJ"
2235 PetscErrorCode MatCopy_MPIAIJ(Mat A,Mat B,MatStructure str)
2236 {
2237   PetscErrorCode ierr;
2238   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
2239   Mat_MPIAIJ     *b = (Mat_MPIAIJ*)B->data;
2240 
2241   PetscFunctionBegin;
2242   /* If the two matrices don't have the same copy implementation, they aren't compatible for fast copy. */
2243   if ((str != SAME_NONZERO_PATTERN) || (A->ops->copy != B->ops->copy)) {
2244     /* because of the column compression in the off-processor part of the matrix a->B,
2245        the number of columns in a->B and b->B may be different, hence we cannot call
2246        the MatCopy() directly on the two parts. If need be, we can provide a more
2247        efficient copy than the MatCopy_Basic() by first uncompressing the a->B matrices
2248        then copying the submatrices */
2249     ierr = MatCopy_Basic(A,B,str);CHKERRQ(ierr);
2250   } else {
2251     ierr = MatCopy(a->A,b->A,str);CHKERRQ(ierr);
2252     ierr = MatCopy(a->B,b->B,str);CHKERRQ(ierr);
2253   }
2254   PetscFunctionReturn(0);
2255 }
2256 
2257 #undef __FUNCT__
2258 #define __FUNCT__ "MatSetUp_MPIAIJ"
2259 PetscErrorCode MatSetUp_MPIAIJ(Mat A)
2260 {
2261   PetscErrorCode ierr;
2262 
2263   PetscFunctionBegin;
2264   ierr =  MatMPIAIJSetPreallocation(A,PETSC_DEFAULT,0,PETSC_DEFAULT,0);CHKERRQ(ierr);
2265   PetscFunctionReturn(0);
2266 }
2267 
2268 #undef __FUNCT__
2269 #define __FUNCT__ "MatAXPYGetPreallocation_MPIAIJ"
2270 /* This is the same as MatAXPYGetPreallocation_SeqAIJ, except that the local-to-global map is provided */
2271 static PetscErrorCode MatAXPYGetPreallocation_MPIAIJ(Mat Y,const PetscInt *yltog,Mat X,const PetscInt *xltog,PetscInt *nnz)
2272 {
2273   PetscInt       i,m=Y->rmap->N;
2274   Mat_SeqAIJ     *x  = (Mat_SeqAIJ*)X->data;
2275   Mat_SeqAIJ     *y  = (Mat_SeqAIJ*)Y->data;
2276   const PetscInt *xi = x->i,*yi = y->i;
2277 
2278   PetscFunctionBegin;
2279   /* Set the number of nonzeros in the new matrix */
2280   for (i=0; i<m; i++) {
2281     PetscInt       j,k,nzx = xi[i+1] - xi[i],nzy = yi[i+1] - yi[i];
2282     const PetscInt *xj = x->j+xi[i],*yj = y->j+yi[i];
2283     nnz[i] = 0;
2284     for (j=0,k=0; j<nzx; j++) {                   /* Point in X */
2285       for (; k<nzy && yltog[yj[k]]<xltog[xj[j]]; k++) nnz[i]++; /* Catch up to X */
2286       if (k<nzy && yltog[yj[k]]==xltog[xj[j]]) k++;             /* Skip duplicate */
2287       nnz[i]++;
2288     }
2289     for (; k<nzy; k++) nnz[i]++;
2290   }
2291   PetscFunctionReturn(0);
2292 }
2293 
2294 #undef __FUNCT__
2295 #define __FUNCT__ "MatAXPY_MPIAIJ"
2296 PetscErrorCode MatAXPY_MPIAIJ(Mat Y,PetscScalar a,Mat X,MatStructure str)
2297 {
2298   PetscErrorCode ierr;
2299   PetscInt       i;
2300   Mat_MPIAIJ     *xx = (Mat_MPIAIJ*)X->data,*yy = (Mat_MPIAIJ*)Y->data;
2301   PetscBLASInt   bnz,one=1;
2302   Mat_SeqAIJ     *x,*y;
2303 
2304   PetscFunctionBegin;
2305   if (str == SAME_NONZERO_PATTERN) {
2306     PetscScalar alpha = a;
2307     x    = (Mat_SeqAIJ*)xx->A->data;
2308     ierr = PetscBLASIntCast(x->nz,&bnz);CHKERRQ(ierr);
2309     y    = (Mat_SeqAIJ*)yy->A->data;
2310     PetscStackCallBLAS("BLASaxpy",BLASaxpy_(&bnz,&alpha,x->a,&one,y->a,&one));
2311     x    = (Mat_SeqAIJ*)xx->B->data;
2312     y    = (Mat_SeqAIJ*)yy->B->data;
2313     ierr = PetscBLASIntCast(x->nz,&bnz);CHKERRQ(ierr);
2314     PetscStackCallBLAS("BLASaxpy",BLASaxpy_(&bnz,&alpha,x->a,&one,y->a,&one));
2315   } else if (str == SUBSET_NONZERO_PATTERN) {
2316     ierr = MatAXPY_SeqAIJ(yy->A,a,xx->A,str);CHKERRQ(ierr);
2317 
2318     x = (Mat_SeqAIJ*)xx->B->data;
2319     y = (Mat_SeqAIJ*)yy->B->data;
2320     if (y->xtoy && y->XtoY != xx->B) {
2321       ierr = PetscFree(y->xtoy);CHKERRQ(ierr);
2322       ierr = MatDestroy(&y->XtoY);CHKERRQ(ierr);
2323     }
2324     if (!y->xtoy) { /* get xtoy */
2325       ierr    = MatAXPYGetxtoy_Private(xx->B->rmap->n,x->i,x->j,xx->garray,y->i,y->j,yy->garray,&y->xtoy);CHKERRQ(ierr);
2326       y->XtoY = xx->B;
2327       ierr    = PetscObjectReference((PetscObject)xx->B);CHKERRQ(ierr);
2328     }
2329     for (i=0; i<x->nz; i++) y->a[y->xtoy[i]] += a*(x->a[i]);
2330   } else {
2331     Mat      B;
2332     PetscInt *nnz_d,*nnz_o;
2333     ierr = PetscMalloc(yy->A->rmap->N*sizeof(PetscInt),&nnz_d);CHKERRQ(ierr);
2334     ierr = PetscMalloc(yy->B->rmap->N*sizeof(PetscInt),&nnz_o);CHKERRQ(ierr);
2335     ierr = MatCreate(PetscObjectComm((PetscObject)Y),&B);CHKERRQ(ierr);
2336     ierr = PetscObjectSetName((PetscObject)B,((PetscObject)Y)->name);CHKERRQ(ierr);
2337     ierr = MatSetSizes(B,Y->rmap->n,Y->cmap->n,Y->rmap->N,Y->cmap->N);CHKERRQ(ierr);
2338     ierr = MatSetBlockSizes(B,Y->rmap->bs,Y->cmap->bs);CHKERRQ(ierr);
2339     ierr = MatSetType(B,MATMPIAIJ);CHKERRQ(ierr);
2340     ierr = MatAXPYGetPreallocation_SeqAIJ(yy->A,xx->A,nnz_d);CHKERRQ(ierr);
2341     ierr = MatAXPYGetPreallocation_MPIAIJ(yy->B,yy->garray,xx->B,xx->garray,nnz_o);CHKERRQ(ierr);
2342     ierr = MatMPIAIJSetPreallocation(B,0,nnz_d,0,nnz_o);CHKERRQ(ierr);
2343     ierr = MatAXPY_BasicWithPreallocation(B,Y,a,X,str);CHKERRQ(ierr);
2344     ierr = MatHeaderReplace(Y,B);CHKERRQ(ierr);
2345     ierr = PetscFree(nnz_d);CHKERRQ(ierr);
2346     ierr = PetscFree(nnz_o);CHKERRQ(ierr);
2347   }
2348   PetscFunctionReturn(0);
2349 }
2350 
2351 extern PetscErrorCode  MatConjugate_SeqAIJ(Mat);
2352 
2353 #undef __FUNCT__
2354 #define __FUNCT__ "MatConjugate_MPIAIJ"
2355 PetscErrorCode  MatConjugate_MPIAIJ(Mat mat)
2356 {
2357 #if defined(PETSC_USE_COMPLEX)
2358   PetscErrorCode ierr;
2359   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
2360 
2361   PetscFunctionBegin;
2362   ierr = MatConjugate_SeqAIJ(aij->A);CHKERRQ(ierr);
2363   ierr = MatConjugate_SeqAIJ(aij->B);CHKERRQ(ierr);
2364 #else
2365   PetscFunctionBegin;
2366 #endif
2367   PetscFunctionReturn(0);
2368 }
2369 
2370 #undef __FUNCT__
2371 #define __FUNCT__ "MatRealPart_MPIAIJ"
2372 PetscErrorCode MatRealPart_MPIAIJ(Mat A)
2373 {
2374   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
2375   PetscErrorCode ierr;
2376 
2377   PetscFunctionBegin;
2378   ierr = MatRealPart(a->A);CHKERRQ(ierr);
2379   ierr = MatRealPart(a->B);CHKERRQ(ierr);
2380   PetscFunctionReturn(0);
2381 }
2382 
2383 #undef __FUNCT__
2384 #define __FUNCT__ "MatImaginaryPart_MPIAIJ"
2385 PetscErrorCode MatImaginaryPart_MPIAIJ(Mat A)
2386 {
2387   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
2388   PetscErrorCode ierr;
2389 
2390   PetscFunctionBegin;
2391   ierr = MatImaginaryPart(a->A);CHKERRQ(ierr);
2392   ierr = MatImaginaryPart(a->B);CHKERRQ(ierr);
2393   PetscFunctionReturn(0);
2394 }
2395 
2396 #if defined(PETSC_HAVE_PBGL)
2397 
2398 #include <boost/parallel/mpi/bsp_process_group.hpp>
2399 #include <boost/graph/distributed/ilu_default_graph.hpp>
2400 #include <boost/graph/distributed/ilu_0_block.hpp>
2401 #include <boost/graph/distributed/ilu_preconditioner.hpp>
2402 #include <boost/graph/distributed/petsc/interface.hpp>
2403 #include <boost/multi_array.hpp>
2404 #include <boost/parallel/distributed_property_map->hpp>
2405 
2406 #undef __FUNCT__
2407 #define __FUNCT__ "MatILUFactorSymbolic_MPIAIJ"
2408 /*
2409   This uses the parallel ILU factorization of Peter Gottschling <pgottsch@osl.iu.edu>
2410 */
2411 PetscErrorCode MatILUFactorSymbolic_MPIAIJ(Mat fact,Mat A, IS isrow, IS iscol, const MatFactorInfo *info)
2412 {
2413   namespace petsc = boost::distributed::petsc;
2414 
2415   namespace graph_dist = boost::graph::distributed;
2416   using boost::graph::distributed::ilu_default::process_group_type;
2417   using boost::graph::ilu_permuted;
2418 
2419   PetscBool      row_identity, col_identity;
2420   PetscContainer c;
2421   PetscInt       m, n, M, N;
2422   PetscErrorCode ierr;
2423 
2424   PetscFunctionBegin;
2425   if (info->levels != 0) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_SUP,"Only levels = 0 supported for parallel ilu");
2426   ierr = ISIdentity(isrow, &row_identity);CHKERRQ(ierr);
2427   ierr = ISIdentity(iscol, &col_identity);CHKERRQ(ierr);
2428   if (!row_identity || !col_identity) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONG,"Row and column permutations must be identity for parallel ILU");
2429 
2430   process_group_type pg;
2431   typedef graph_dist::ilu_default::ilu_level_graph_type lgraph_type;
2432   lgraph_type  *lgraph_p   = new lgraph_type(petsc::num_global_vertices(A), pg, petsc::matrix_distribution(A, pg));
2433   lgraph_type& level_graph = *lgraph_p;
2434   graph_dist::ilu_default::graph_type&            graph(level_graph.graph);
2435 
2436   petsc::read_matrix(A, graph, get(boost::edge_weight, graph));
2437   ilu_permuted(level_graph);
2438 
2439   /* put together the new matrix */
2440   ierr = MatCreate(PetscObjectComm((PetscObject)A), fact);CHKERRQ(ierr);
2441   ierr = MatGetLocalSize(A, &m, &n);CHKERRQ(ierr);
2442   ierr = MatGetSize(A, &M, &N);CHKERRQ(ierr);
2443   ierr = MatSetSizes(fact, m, n, M, N);CHKERRQ(ierr);
2444   ierr = MatSetBlockSizes(fact,A->rmap->bs,A->cmap->bs);CHKERRQ(ierr);
2445   ierr = MatSetType(fact, ((PetscObject)A)->type_name);CHKERRQ(ierr);
2446   ierr = MatAssemblyBegin(fact, MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
2447   ierr = MatAssemblyEnd(fact, MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
2448 
2449   ierr = PetscContainerCreate(PetscObjectComm((PetscObject)A), &c);
2450   ierr = PetscContainerSetPointer(c, lgraph_p);
2451   ierr = PetscObjectCompose((PetscObject) (fact), "graph", (PetscObject) c);
2452   ierr = PetscContainerDestroy(&c);
2453   PetscFunctionReturn(0);
2454 }
2455 
2456 #undef __FUNCT__
2457 #define __FUNCT__ "MatLUFactorNumeric_MPIAIJ"
2458 PetscErrorCode MatLUFactorNumeric_MPIAIJ(Mat B,Mat A, const MatFactorInfo *info)
2459 {
2460   PetscFunctionBegin;
2461   PetscFunctionReturn(0);
2462 }
2463 
2464 #undef __FUNCT__
2465 #define __FUNCT__ "MatSolve_MPIAIJ"
2466 /*
2467   This uses the parallel ILU factorization of Peter Gottschling <pgottsch@osl.iu.edu>
2468 */
2469 PetscErrorCode MatSolve_MPIAIJ(Mat A, Vec b, Vec x)
2470 {
2471   namespace graph_dist = boost::graph::distributed;
2472 
2473   typedef graph_dist::ilu_default::ilu_level_graph_type lgraph_type;
2474   lgraph_type    *lgraph_p;
2475   PetscContainer c;
2476   PetscErrorCode ierr;
2477 
2478   PetscFunctionBegin;
2479   ierr = PetscObjectQuery((PetscObject) A, "graph", (PetscObject*) &c);CHKERRQ(ierr);
2480   ierr = PetscContainerGetPointer(c, (void**) &lgraph_p);CHKERRQ(ierr);
2481   ierr = VecCopy(b, x);CHKERRQ(ierr);
2482 
2483   PetscScalar *array_x;
2484   ierr = VecGetArray(x, &array_x);CHKERRQ(ierr);
2485   PetscInt sx;
2486   ierr = VecGetSize(x, &sx);CHKERRQ(ierr);
2487 
2488   PetscScalar *array_b;
2489   ierr = VecGetArray(b, &array_b);CHKERRQ(ierr);
2490   PetscInt sb;
2491   ierr = VecGetSize(b, &sb);CHKERRQ(ierr);
2492 
2493   lgraph_type& level_graph = *lgraph_p;
2494   graph_dist::ilu_default::graph_type&            graph(level_graph.graph);
2495 
2496   typedef boost::multi_array_ref<PetscScalar, 1> array_ref_type;
2497   array_ref_type                                 ref_b(array_b, boost::extents[num_vertices(graph)]);
2498   array_ref_type                                 ref_x(array_x, boost::extents[num_vertices(graph)]);
2499 
2500   typedef boost::iterator_property_map<array_ref_type::iterator,
2501                                        boost::property_map<graph_dist::ilu_default::graph_type, boost::vertex_index_t>::type>  gvector_type;
2502   gvector_type                                   vector_b(ref_b.begin(), get(boost::vertex_index, graph));
2503   gvector_type                                   vector_x(ref_x.begin(), get(boost::vertex_index, graph));
2504 
2505   ilu_set_solve(*lgraph_p, vector_b, vector_x);
2506   PetscFunctionReturn(0);
2507 }
2508 #endif
2509 
2510 #undef __FUNCT__
2511 #define __FUNCT__ "MatDestroy_MatRedundant"
2512 PetscErrorCode MatDestroy_MatRedundant(Mat A)
2513 {
2514   PetscErrorCode ierr;
2515   Mat_Redundant  *redund;
2516   PetscInt       i;
2517   PetscMPIInt    size;
2518 
2519   PetscFunctionBegin;
2520   ierr = MPI_Comm_size(((PetscObject)A)->comm,&size);CHKERRQ(ierr);
2521   if (size == 1) {
2522     Mat_SeqAIJ *a = (Mat_SeqAIJ*)A->data;
2523     redund = a->redundant;
2524   } else {
2525     Mat_MPIAIJ *a = (Mat_MPIAIJ*)A->data;
2526     redund = a->redundant;
2527   }
2528   if (redund){
2529     if (redund->matseq) { /* via MatGetSubMatrices()  */
2530       ierr = ISDestroy(&redund->isrow);CHKERRQ(ierr);
2531       ierr = ISDestroy(&redund->iscol);CHKERRQ(ierr);
2532       ierr = MatDestroy(&redund->matseq[0]);CHKERRQ(ierr);
2533       ierr = PetscFree(redund->matseq);CHKERRQ(ierr);
2534     } else {
2535       ierr = PetscFree2(redund->send_rank,redund->recv_rank);CHKERRQ(ierr);
2536       ierr = PetscFree(redund->sbuf_j);CHKERRQ(ierr);
2537       ierr = PetscFree(redund->sbuf_a);CHKERRQ(ierr);
2538       for (i=0; i<redund->nrecvs; i++) {
2539         ierr = PetscFree(redund->rbuf_j[i]);CHKERRQ(ierr);
2540         ierr = PetscFree(redund->rbuf_a[i]);CHKERRQ(ierr);
2541       }
2542       ierr = PetscFree4(redund->sbuf_nz,redund->rbuf_nz,redund->rbuf_j,redund->rbuf_a);CHKERRQ(ierr);
2543     }
2544 
2545     if (redund->psubcomm) {
2546       ierr = PetscSubcommDestroy(&redund->psubcomm);CHKERRQ(ierr);
2547     }
2548     ierr = redund->Destroy(A);CHKERRQ(ierr);
2549     ierr = PetscFree(redund);CHKERRQ(ierr);
2550   }
2551   PetscFunctionReturn(0);
2552 }
2553 
2554 #undef __FUNCT__
2555 #define __FUNCT__ "MatGetRedundantMatrix_MPIAIJ_interlaced"
2556 PetscErrorCode MatGetRedundantMatrix_MPIAIJ_interlaced(Mat mat,PetscInt nsubcomm,PetscSubcomm psubcomm,MatReuse reuse,Mat *matredundant)
2557 {
2558   PetscMPIInt    rank,size;
2559   MPI_Comm       comm,subcomm=psubcomm->comm;
2560   PetscErrorCode ierr;
2561   PetscInt       nsends=0,nrecvs=0,i,rownz_max=0,M=mat->rmap->N,N=mat->cmap->N;
2562   PetscMPIInt    *send_rank= NULL,*recv_rank=NULL,subrank,subsize;
2563   PetscInt       *rowrange = mat->rmap->range;
2564   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
2565   Mat            A = aij->A,B=aij->B,C=*matredundant;
2566   Mat_SeqAIJ     *a = (Mat_SeqAIJ*)A->data,*b=(Mat_SeqAIJ*)B->data;
2567   PetscScalar    *sbuf_a;
2568   PetscInt       nzlocal=a->nz+b->nz;
2569   PetscInt       j,cstart=mat->cmap->rstart,cend=mat->cmap->rend,row,nzA,nzB,ncols,*cworkA,*cworkB;
2570   PetscInt       rstart=mat->rmap->rstart,rend=mat->rmap->rend,*bmap=aij->garray;
2571   PetscInt       *cols,ctmp,lwrite,*rptr,l,*sbuf_j;
2572   MatScalar      *aworkA,*aworkB;
2573   PetscScalar    *vals;
2574   PetscMPIInt    tag1,tag2,tag3,imdex;
2575   MPI_Request    *s_waits1=NULL,*s_waits2=NULL,*s_waits3=NULL;
2576   MPI_Request    *r_waits1=NULL,*r_waits2=NULL,*r_waits3=NULL;
2577   MPI_Status     recv_status,*send_status;
2578   PetscInt       *sbuf_nz=NULL,*rbuf_nz=NULL,count;
2579   PetscInt       **rbuf_j=NULL;
2580   PetscScalar    **rbuf_a=NULL;
2581   Mat_Redundant  *redund =NULL;
2582 
2583   PetscFunctionBegin;
2584   ierr = PetscObjectGetComm((PetscObject)mat,&comm);CHKERRQ(ierr);
2585   ierr = MPI_Comm_rank(comm,&rank);CHKERRQ(ierr);
2586   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
2587   ierr = MPI_Comm_rank(subcomm,&subrank);CHKERRQ(ierr);
2588   ierr = MPI_Comm_size(subcomm,&subsize);CHKERRQ(ierr);
2589 
2590   if (reuse == MAT_REUSE_MATRIX) {
2591     if (M != mat->rmap->N || N != mat->cmap->N) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_SIZ,"Cannot reuse matrix. Wrong global size");
2592     if (subsize == 1) {
2593       Mat_SeqAIJ *c = (Mat_SeqAIJ*)C->data;
2594       redund = c->redundant;
2595     } else {
2596       Mat_MPIAIJ *c = (Mat_MPIAIJ*)C->data;
2597       redund = c->redundant;
2598     }
2599     if (nzlocal != redund->nzlocal) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_SIZ,"Cannot reuse matrix. Wrong nzlocal");
2600 
2601     nsends    = redund->nsends;
2602     nrecvs    = redund->nrecvs;
2603     send_rank = redund->send_rank;
2604     recv_rank = redund->recv_rank;
2605     sbuf_nz   = redund->sbuf_nz;
2606     rbuf_nz   = redund->rbuf_nz;
2607     sbuf_j    = redund->sbuf_j;
2608     sbuf_a    = redund->sbuf_a;
2609     rbuf_j    = redund->rbuf_j;
2610     rbuf_a    = redund->rbuf_a;
2611   }
2612 
2613   if (reuse == MAT_INITIAL_MATRIX) {
2614     PetscInt    nleftover,np_subcomm;
2615 
2616     /* get the destination processors' id send_rank, nsends and nrecvs */
2617     ierr = PetscMalloc2(size,PetscMPIInt,&send_rank,size,PetscMPIInt,&recv_rank);CHKERRQ(ierr);
2618 
2619     np_subcomm = size/nsubcomm;
2620     nleftover  = size - nsubcomm*np_subcomm;
2621 
2622     /* block of codes below is specific for INTERLACED */
2623     /* ------------------------------------------------*/
2624     nsends = 0; nrecvs = 0;
2625     for (i=0; i<size; i++) {
2626       if (subrank == i/nsubcomm && i != rank) { /* my_subrank == other's subrank */
2627         send_rank[nsends++] = i;
2628         recv_rank[nrecvs++] = i;
2629       }
2630     }
2631     if (rank >= size - nleftover) { /* this proc is a leftover processor */
2632       i = size-nleftover-1;
2633       j = 0;
2634       while (j < nsubcomm - nleftover) {
2635         send_rank[nsends++] = i;
2636         i--; j++;
2637       }
2638     }
2639 
2640     if (nleftover && subsize == size/nsubcomm && subrank==subsize-1) { /* this proc recvs from leftover processors */
2641       for (i=0; i<nleftover; i++) {
2642         recv_rank[nrecvs++] = size-nleftover+i;
2643       }
2644     }
2645     /*----------------------------------------------*/
2646 
2647     /* allocate sbuf_j, sbuf_a */
2648     i    = nzlocal + rowrange[rank+1] - rowrange[rank] + 2;
2649     ierr = PetscMalloc(i*sizeof(PetscInt),&sbuf_j);CHKERRQ(ierr);
2650     ierr = PetscMalloc((nzlocal+1)*sizeof(PetscScalar),&sbuf_a);CHKERRQ(ierr);
2651     /*
2652     ierr = PetscSynchronizedPrintf(comm,"[%d] nsends %d, nrecvs %d\n",rank,nsends,nrecvs);CHKERRQ(ierr);
2653     ierr = PetscSynchronizedFlush(comm);CHKERRQ(ierr);
2654      */
2655   } /* endof if (reuse == MAT_INITIAL_MATRIX) */
2656 
2657   /* copy mat's local entries into the buffers */
2658   if (reuse == MAT_INITIAL_MATRIX) {
2659     rownz_max = 0;
2660     rptr      = sbuf_j;
2661     cols      = sbuf_j + rend-rstart + 1;
2662     vals      = sbuf_a;
2663     rptr[0]   = 0;
2664     for (i=0; i<rend-rstart; i++) {
2665       row    = i + rstart;
2666       nzA    = a->i[i+1] - a->i[i]; nzB = b->i[i+1] - b->i[i];
2667       ncols  = nzA + nzB;
2668       cworkA = a->j + a->i[i]; cworkB = b->j + b->i[i];
2669       aworkA = a->a + a->i[i]; aworkB = b->a + b->i[i];
2670       /* load the column indices for this row into cols */
2671       lwrite = 0;
2672       for (l=0; l<nzB; l++) {
2673         if ((ctmp = bmap[cworkB[l]]) < cstart) {
2674           vals[lwrite]   = aworkB[l];
2675           cols[lwrite++] = ctmp;
2676         }
2677       }
2678       for (l=0; l<nzA; l++) {
2679         vals[lwrite]   = aworkA[l];
2680         cols[lwrite++] = cstart + cworkA[l];
2681       }
2682       for (l=0; l<nzB; l++) {
2683         if ((ctmp = bmap[cworkB[l]]) >= cend) {
2684           vals[lwrite]   = aworkB[l];
2685           cols[lwrite++] = ctmp;
2686         }
2687       }
2688       vals     += ncols;
2689       cols     += ncols;
2690       rptr[i+1] = rptr[i] + ncols;
2691       if (rownz_max < ncols) rownz_max = ncols;
2692     }
2693     if (rptr[rend-rstart] != a->nz + b->nz) SETERRQ4(PETSC_COMM_SELF,PETSC_ERR_PLIB, "rptr[%d] %d != %d + %d",rend-rstart,rptr[rend-rstart+1],a->nz,b->nz);
2694   } else { /* only copy matrix values into sbuf_a */
2695     rptr    = sbuf_j;
2696     vals    = sbuf_a;
2697     rptr[0] = 0;
2698     for (i=0; i<rend-rstart; i++) {
2699       row    = i + rstart;
2700       nzA    = a->i[i+1] - a->i[i]; nzB = b->i[i+1] - b->i[i];
2701       ncols  = nzA + nzB;
2702       cworkB = b->j + b->i[i];
2703       aworkA = a->a + a->i[i];
2704       aworkB = b->a + b->i[i];
2705       lwrite = 0;
2706       for (l=0; l<nzB; l++) {
2707         if ((ctmp = bmap[cworkB[l]]) < cstart) vals[lwrite++] = aworkB[l];
2708       }
2709       for (l=0; l<nzA; l++) vals[lwrite++] = aworkA[l];
2710       for (l=0; l<nzB; l++) {
2711         if ((ctmp = bmap[cworkB[l]]) >= cend) vals[lwrite++] = aworkB[l];
2712       }
2713       vals     += ncols;
2714       rptr[i+1] = rptr[i] + ncols;
2715     }
2716   } /* endof if (reuse == MAT_INITIAL_MATRIX) */
2717 
2718   /* send nzlocal to others, and recv other's nzlocal */
2719   /*--------------------------------------------------*/
2720   if (reuse == MAT_INITIAL_MATRIX) {
2721     ierr = PetscMalloc2(3*(nsends + nrecvs)+1,MPI_Request,&s_waits3,nsends+1,MPI_Status,&send_status);CHKERRQ(ierr);
2722 
2723     s_waits2 = s_waits3 + nsends;
2724     s_waits1 = s_waits2 + nsends;
2725     r_waits1 = s_waits1 + nsends;
2726     r_waits2 = r_waits1 + nrecvs;
2727     r_waits3 = r_waits2 + nrecvs;
2728   } else {
2729     ierr = PetscMalloc2(nsends + nrecvs +1,MPI_Request,&s_waits3,nsends+1,MPI_Status,&send_status);CHKERRQ(ierr);
2730 
2731     r_waits3 = s_waits3 + nsends;
2732   }
2733 
2734   ierr = PetscObjectGetNewTag((PetscObject)mat,&tag3);CHKERRQ(ierr);
2735   if (reuse == MAT_INITIAL_MATRIX) {
2736     /* get new tags to keep the communication clean */
2737     ierr = PetscObjectGetNewTag((PetscObject)mat,&tag1);CHKERRQ(ierr);
2738     ierr = PetscObjectGetNewTag((PetscObject)mat,&tag2);CHKERRQ(ierr);
2739     ierr = PetscMalloc4(nsends,PetscInt,&sbuf_nz,nrecvs,PetscInt,&rbuf_nz,nrecvs,PetscInt*,&rbuf_j,nrecvs,PetscScalar*,&rbuf_a);CHKERRQ(ierr);
2740 
2741     /* post receives of other's nzlocal */
2742     for (i=0; i<nrecvs; i++) {
2743       ierr = MPI_Irecv(rbuf_nz+i,1,MPIU_INT,MPI_ANY_SOURCE,tag1,comm,r_waits1+i);CHKERRQ(ierr);
2744     }
2745     /* send nzlocal to others */
2746     for (i=0; i<nsends; i++) {
2747       sbuf_nz[i] = nzlocal;
2748       ierr       = MPI_Isend(sbuf_nz+i,1,MPIU_INT,send_rank[i],tag1,comm,s_waits1+i);CHKERRQ(ierr);
2749     }
2750     /* wait on receives of nzlocal; allocate space for rbuf_j, rbuf_a */
2751     count = nrecvs;
2752     while (count) {
2753       ierr = MPI_Waitany(nrecvs,r_waits1,&imdex,&recv_status);CHKERRQ(ierr);
2754 
2755       recv_rank[imdex] = recv_status.MPI_SOURCE;
2756       /* allocate rbuf_a and rbuf_j; then post receives of rbuf_j */
2757       ierr = PetscMalloc((rbuf_nz[imdex]+1)*sizeof(PetscScalar),&rbuf_a[imdex]);CHKERRQ(ierr);
2758 
2759       i = rowrange[recv_status.MPI_SOURCE+1] - rowrange[recv_status.MPI_SOURCE]; /* number of expected mat->i */
2760 
2761       rbuf_nz[imdex] += i + 2;
2762 
2763       ierr = PetscMalloc(rbuf_nz[imdex]*sizeof(PetscInt),&rbuf_j[imdex]);CHKERRQ(ierr);
2764       ierr = MPI_Irecv(rbuf_j[imdex],rbuf_nz[imdex],MPIU_INT,recv_status.MPI_SOURCE,tag2,comm,r_waits2+imdex);CHKERRQ(ierr);
2765       count--;
2766     }
2767     /* wait on sends of nzlocal */
2768     if (nsends) {ierr = MPI_Waitall(nsends,s_waits1,send_status);CHKERRQ(ierr);}
2769     /* send mat->i,j to others, and recv from other's */
2770     /*------------------------------------------------*/
2771     for (i=0; i<nsends; i++) {
2772       j    = nzlocal + rowrange[rank+1] - rowrange[rank] + 1;
2773       ierr = MPI_Isend(sbuf_j,j,MPIU_INT,send_rank[i],tag2,comm,s_waits2+i);CHKERRQ(ierr);
2774     }
2775     /* wait on receives of mat->i,j */
2776     /*------------------------------*/
2777     count = nrecvs;
2778     while (count) {
2779       ierr = MPI_Waitany(nrecvs,r_waits2,&imdex,&recv_status);CHKERRQ(ierr);
2780       if (recv_rank[imdex] != recv_status.MPI_SOURCE) SETERRQ2(PETSC_COMM_SELF,1, "recv_rank %d != MPI_SOURCE %d",recv_rank[imdex],recv_status.MPI_SOURCE);
2781       count--;
2782     }
2783     /* wait on sends of mat->i,j */
2784     /*---------------------------*/
2785     if (nsends) {
2786       ierr = MPI_Waitall(nsends,s_waits2,send_status);CHKERRQ(ierr);
2787     }
2788   } /* endof if (reuse == MAT_INITIAL_MATRIX) */
2789 
2790   /* post receives, send and receive mat->a */
2791   /*----------------------------------------*/
2792   for (imdex=0; imdex<nrecvs; imdex++) {
2793     ierr = MPI_Irecv(rbuf_a[imdex],rbuf_nz[imdex],MPIU_SCALAR,recv_rank[imdex],tag3,comm,r_waits3+imdex);CHKERRQ(ierr);
2794   }
2795   for (i=0; i<nsends; i++) {
2796     ierr = MPI_Isend(sbuf_a,nzlocal,MPIU_SCALAR,send_rank[i],tag3,comm,s_waits3+i);CHKERRQ(ierr);
2797   }
2798   count = nrecvs;
2799   while (count) {
2800     ierr = MPI_Waitany(nrecvs,r_waits3,&imdex,&recv_status);CHKERRQ(ierr);
2801     if (recv_rank[imdex] != recv_status.MPI_SOURCE) SETERRQ2(PETSC_COMM_SELF,1, "recv_rank %d != MPI_SOURCE %d",recv_rank[imdex],recv_status.MPI_SOURCE);
2802     count--;
2803   }
2804   if (nsends) {
2805     ierr = MPI_Waitall(nsends,s_waits3,send_status);CHKERRQ(ierr);
2806   }
2807 
2808   ierr = PetscFree2(s_waits3,send_status);CHKERRQ(ierr);
2809 
2810   /* create redundant matrix */
2811   /*-------------------------*/
2812   if (reuse == MAT_INITIAL_MATRIX) {
2813     const PetscInt *range;
2814     PetscInt       rstart_sub,rend_sub,mloc_sub;
2815 
2816     /* compute rownz_max for preallocation */
2817     for (imdex=0; imdex<nrecvs; imdex++) {
2818       j    = rowrange[recv_rank[imdex]+1] - rowrange[recv_rank[imdex]];
2819       rptr = rbuf_j[imdex];
2820       for (i=0; i<j; i++) {
2821         ncols = rptr[i+1] - rptr[i];
2822         if (rownz_max < ncols) rownz_max = ncols;
2823       }
2824     }
2825 
2826     ierr = MatCreate(subcomm,&C);CHKERRQ(ierr);
2827 
2828     /* get local size of redundant matrix
2829        - mloc_sub is chosen for PETSC_SUBCOMM_INTERLACED, works for other types, but may not efficient! */
2830     ierr = MatGetOwnershipRanges(mat,&range);CHKERRQ(ierr);
2831     rstart_sub = range[nsubcomm*subrank];
2832     if (subrank+1 < subsize) { /* not the last proc in subcomm */
2833       rend_sub = range[nsubcomm*(subrank+1)];
2834     } else {
2835       rend_sub = mat->rmap->N;
2836     }
2837     mloc_sub = rend_sub - rstart_sub;
2838 
2839     if (M == N) {
2840       ierr = MatSetSizes(C,mloc_sub,mloc_sub,PETSC_DECIDE,PETSC_DECIDE);CHKERRQ(ierr);
2841     } else { /* non-square matrix */
2842       ierr = MatSetSizes(C,mloc_sub,PETSC_DECIDE,PETSC_DECIDE,mat->cmap->N);CHKERRQ(ierr);
2843     }
2844     ierr = MatSetBlockSizes(C,mat->rmap->bs,mat->cmap->bs);CHKERRQ(ierr);
2845     ierr = MatSetFromOptions(C);CHKERRQ(ierr);
2846     ierr = MatSeqAIJSetPreallocation(C,rownz_max,NULL);CHKERRQ(ierr);
2847     ierr = MatMPIAIJSetPreallocation(C,rownz_max,NULL,rownz_max,NULL);CHKERRQ(ierr);
2848   } else {
2849     C = *matredundant;
2850   }
2851 
2852   /* insert local matrix entries */
2853   rptr = sbuf_j;
2854   cols = sbuf_j + rend-rstart + 1;
2855   vals = sbuf_a;
2856   for (i=0; i<rend-rstart; i++) {
2857     row   = i + rstart;
2858     ncols = rptr[i+1] - rptr[i];
2859     ierr  = MatSetValues(C,1,&row,ncols,cols,vals,INSERT_VALUES);CHKERRQ(ierr);
2860     vals += ncols;
2861     cols += ncols;
2862   }
2863   /* insert received matrix entries */
2864   for (imdex=0; imdex<nrecvs; imdex++) {
2865     rstart = rowrange[recv_rank[imdex]];
2866     rend   = rowrange[recv_rank[imdex]+1];
2867     /* printf("[%d] insert rows %d - %d\n",rank,rstart,rend-1); */
2868     rptr   = rbuf_j[imdex];
2869     cols   = rbuf_j[imdex] + rend-rstart + 1;
2870     vals   = rbuf_a[imdex];
2871     for (i=0; i<rend-rstart; i++) {
2872       row   = i + rstart;
2873       ncols = rptr[i+1] - rptr[i];
2874       ierr  = MatSetValues(C,1,&row,ncols,cols,vals,INSERT_VALUES);CHKERRQ(ierr);
2875       vals += ncols;
2876       cols += ncols;
2877     }
2878   }
2879   ierr = MatAssemblyBegin(C,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
2880   ierr = MatAssemblyEnd(C,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
2881 
2882   if (reuse == MAT_INITIAL_MATRIX) {
2883     *matredundant = C;
2884 
2885     /* create a supporting struct and attach it to C for reuse */
2886     ierr = PetscNewLog(C,Mat_Redundant,&redund);CHKERRQ(ierr);
2887     if (subsize == 1) {
2888       Mat_SeqAIJ *c = (Mat_SeqAIJ*)C->data;
2889       c->redundant = redund;
2890     } else {
2891       Mat_MPIAIJ *c = (Mat_MPIAIJ*)C->data;
2892       c->redundant = redund;
2893     }
2894 
2895     redund->nzlocal   = nzlocal;
2896     redund->nsends    = nsends;
2897     redund->nrecvs    = nrecvs;
2898     redund->send_rank = send_rank;
2899     redund->recv_rank = recv_rank;
2900     redund->sbuf_nz   = sbuf_nz;
2901     redund->rbuf_nz   = rbuf_nz;
2902     redund->sbuf_j    = sbuf_j;
2903     redund->sbuf_a    = sbuf_a;
2904     redund->rbuf_j    = rbuf_j;
2905     redund->rbuf_a    = rbuf_a;
2906     redund->psubcomm  = NULL;
2907 
2908     redund->Destroy = C->ops->destroy;
2909     C->ops->destroy = MatDestroy_MatRedundant;
2910   }
2911   PetscFunctionReturn(0);
2912 }
2913 
2914 #undef __FUNCT__
2915 #define __FUNCT__ "MatGetRedundantMatrix_MPIAIJ"
2916 PetscErrorCode MatGetRedundantMatrix_MPIAIJ(Mat mat,PetscInt nsubcomm,MPI_Comm subcomm,PetscSubcomm psubcomm,MatReuse reuse,Mat *matredundant)
2917 {
2918   PetscErrorCode ierr;
2919   MPI_Comm       comm;
2920   PetscMPIInt    size,subsize;
2921   PetscInt       mloc_sub,rstart,rend,M=mat->rmap->N,N=mat->cmap->N;
2922   Mat_Redundant  *redund =NULL;
2923   PetscSubcomm   psubcomm_in=psubcomm;
2924   MPI_Comm       subcomm_in=subcomm;
2925 
2926   PetscFunctionBegin;
2927   if (subcomm_in == MPI_COMM_NULL) { /* use psubcomm */
2928     if (reuse ==  MAT_INITIAL_MATRIX) {
2929       if (psubcomm_in == NULL) { /* user does not provide psubcomm, create it here */
2930         ierr = PetscObjectGetComm((PetscObject)mat,&comm);CHKERRQ(ierr);
2931         ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
2932         ierr = PetscSubcommCreate(comm,&psubcomm);CHKERRQ(ierr);
2933         ierr = PetscSubcommSetNumber(psubcomm,nsubcomm);CHKERRQ(ierr);
2934         ierr = PetscSubcommSetType(psubcomm,PETSC_SUBCOMM_CONTIGUOUS);CHKERRQ(ierr);
2935         ierr = PetscSubcommSetFromOptions(psubcomm);CHKERRQ(ierr);
2936       }
2937       subcomm = psubcomm->comm;
2938       ierr = MPI_Comm_size(subcomm,&subsize);CHKERRQ(ierr);
2939     } else { /* retrieve psubcomm */
2940       if (psubcomm_in == NULL) { /* user does not provide psubcomm */
2941         ierr = PetscObjectGetComm((PetscObject)(*matredundant),&subcomm);CHKERRQ(ierr);
2942         ierr = MPI_Comm_size(subcomm,&subsize);CHKERRQ(ierr);
2943         if (subsize == 1) {
2944           Mat_SeqAIJ *c = (Mat_SeqAIJ*)(*matredundant)->data;
2945           psubcomm = c->redundant->psubcomm;
2946         } else {
2947           Mat_MPIAIJ *c = (Mat_MPIAIJ*)(*matredundant)->data;
2948           psubcomm = c->redundant->psubcomm;
2949         }
2950       } else { /* use psubcomm_in */
2951         subcomm = psubcomm_in->comm;
2952         ierr = MPI_Comm_size(subcomm,&subsize);CHKERRQ(ierr);
2953       }
2954     }
2955   }
2956 
2957   if (subcomm_in == MPI_COMM_NULL && psubcomm->type == PETSC_SUBCOMM_INTERLACED) {
2958      ierr = MatGetRedundantMatrix_MPIAIJ_interlaced(mat,nsubcomm,psubcomm,reuse,matredundant);CHKERRQ(ierr);
2959   } else {
2960     /* via MatGetSubMatrices() */
2961     Mat  *matseq;
2962     IS   isrow,iscol;
2963 
2964     if (reuse == MAT_INITIAL_MATRIX) {
2965       /* create a local sequential matrix matseq[0] */
2966       mloc_sub = PETSC_DECIDE;
2967       ierr = PetscSplitOwnership(subcomm,&mloc_sub,&M);CHKERRQ(ierr);
2968       ierr = MPI_Scan(&mloc_sub,&rend,1,MPIU_INT,MPI_SUM,subcomm);CHKERRQ(ierr);
2969       rstart = rend - mloc_sub;
2970       ierr = ISCreateStride(PETSC_COMM_SELF,mloc_sub,rstart,1,&isrow);CHKERRQ(ierr);
2971       ierr = ISCreateStride(PETSC_COMM_SELF,N,0,1,&iscol);CHKERRQ(ierr);
2972     } else { /* reuse == MAT_REUSE_MATRIX */
2973       if (subsize == 1) {
2974         Mat_SeqAIJ *c = (Mat_SeqAIJ*)(*matredundant)->data;
2975         redund = c->redundant;
2976       } else {
2977         Mat_MPIAIJ *c = (Mat_MPIAIJ*)(*matredundant)->data;
2978         redund = c->redundant;
2979       }
2980 
2981       isrow  = redund->isrow;
2982       iscol  = redund->iscol;
2983       matseq = redund->matseq;
2984     }
2985     ierr = MatGetSubMatrices(mat,1,&isrow,&iscol,reuse,&matseq);CHKERRQ(ierr);
2986     ierr = MatCreateMPIAIJConcatenateSeqAIJ(subcomm,matseq[0],PETSC_DECIDE,reuse,matredundant);CHKERRQ(ierr);
2987 
2988     if (reuse == MAT_INITIAL_MATRIX) {
2989       /* create a supporting struct and attach it to C for reuse */
2990       ierr = PetscNewLog(*matredundant,Mat_Redundant,&redund);CHKERRQ(ierr);
2991       if (subsize == 1) {
2992         Mat_SeqAIJ *c = (Mat_SeqAIJ*)(*matredundant)->data;
2993         c->redundant = redund;
2994       } else {
2995         Mat_MPIAIJ *c = (Mat_MPIAIJ*)(*matredundant)->data;
2996         c->redundant = redund;
2997       }
2998       redund->isrow    = isrow;
2999       redund->iscol    = iscol;
3000       redund->matseq   = matseq;
3001       redund->psubcomm = NULL;
3002       redund->Destroy               = (*matredundant)->ops->destroy;
3003       (*matredundant)->ops->destroy = MatDestroy_MatRedundant;
3004     }
3005   }
3006 
3007   if (psubcomm && psubcomm_in==NULL) {
3008     /* if psubcomm is created in this routine, free it in MatDestroy_MatRedundant() */
3009     ierr = MPI_Comm_size(psubcomm->comm,&subsize);CHKERRQ(ierr);
3010     if (subsize == 1) {
3011       Mat_SeqAIJ *c = (Mat_SeqAIJ*)(*matredundant)->data;
3012       c->redundant->psubcomm = psubcomm;
3013     } else {
3014       Mat_MPIAIJ *c = (Mat_MPIAIJ*)(*matredundant)->data;
3015       c->redundant->psubcomm = psubcomm ;
3016     }
3017   }
3018   PetscFunctionReturn(0);
3019 }
3020 
3021 #undef __FUNCT__
3022 #define __FUNCT__ "MatGetRowMaxAbs_MPIAIJ"
3023 PetscErrorCode MatGetRowMaxAbs_MPIAIJ(Mat A, Vec v, PetscInt idx[])
3024 {
3025   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
3026   PetscErrorCode ierr;
3027   PetscInt       i,*idxb = 0;
3028   PetscScalar    *va,*vb;
3029   Vec            vtmp;
3030 
3031   PetscFunctionBegin;
3032   ierr = MatGetRowMaxAbs(a->A,v,idx);CHKERRQ(ierr);
3033   ierr = VecGetArray(v,&va);CHKERRQ(ierr);
3034   if (idx) {
3035     for (i=0; i<A->rmap->n; i++) {
3036       if (PetscAbsScalar(va[i])) idx[i] += A->cmap->rstart;
3037     }
3038   }
3039 
3040   ierr = VecCreateSeq(PETSC_COMM_SELF,A->rmap->n,&vtmp);CHKERRQ(ierr);
3041   if (idx) {
3042     ierr = PetscMalloc(A->rmap->n*sizeof(PetscInt),&idxb);CHKERRQ(ierr);
3043   }
3044   ierr = MatGetRowMaxAbs(a->B,vtmp,idxb);CHKERRQ(ierr);
3045   ierr = VecGetArray(vtmp,&vb);CHKERRQ(ierr);
3046 
3047   for (i=0; i<A->rmap->n; i++) {
3048     if (PetscAbsScalar(va[i]) < PetscAbsScalar(vb[i])) {
3049       va[i] = vb[i];
3050       if (idx) idx[i] = a->garray[idxb[i]];
3051     }
3052   }
3053 
3054   ierr = VecRestoreArray(v,&va);CHKERRQ(ierr);
3055   ierr = VecRestoreArray(vtmp,&vb);CHKERRQ(ierr);
3056   ierr = PetscFree(idxb);CHKERRQ(ierr);
3057   ierr = VecDestroy(&vtmp);CHKERRQ(ierr);
3058   PetscFunctionReturn(0);
3059 }
3060 
3061 #undef __FUNCT__
3062 #define __FUNCT__ "MatGetRowMinAbs_MPIAIJ"
3063 PetscErrorCode MatGetRowMinAbs_MPIAIJ(Mat A, Vec v, PetscInt idx[])
3064 {
3065   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
3066   PetscErrorCode ierr;
3067   PetscInt       i,*idxb = 0;
3068   PetscScalar    *va,*vb;
3069   Vec            vtmp;
3070 
3071   PetscFunctionBegin;
3072   ierr = MatGetRowMinAbs(a->A,v,idx);CHKERRQ(ierr);
3073   ierr = VecGetArray(v,&va);CHKERRQ(ierr);
3074   if (idx) {
3075     for (i=0; i<A->cmap->n; i++) {
3076       if (PetscAbsScalar(va[i])) idx[i] += A->cmap->rstart;
3077     }
3078   }
3079 
3080   ierr = VecCreateSeq(PETSC_COMM_SELF,A->rmap->n,&vtmp);CHKERRQ(ierr);
3081   if (idx) {
3082     ierr = PetscMalloc(A->rmap->n*sizeof(PetscInt),&idxb);CHKERRQ(ierr);
3083   }
3084   ierr = MatGetRowMinAbs(a->B,vtmp,idxb);CHKERRQ(ierr);
3085   ierr = VecGetArray(vtmp,&vb);CHKERRQ(ierr);
3086 
3087   for (i=0; i<A->rmap->n; i++) {
3088     if (PetscAbsScalar(va[i]) > PetscAbsScalar(vb[i])) {
3089       va[i] = vb[i];
3090       if (idx) idx[i] = a->garray[idxb[i]];
3091     }
3092   }
3093 
3094   ierr = VecRestoreArray(v,&va);CHKERRQ(ierr);
3095   ierr = VecRestoreArray(vtmp,&vb);CHKERRQ(ierr);
3096   ierr = PetscFree(idxb);CHKERRQ(ierr);
3097   ierr = VecDestroy(&vtmp);CHKERRQ(ierr);
3098   PetscFunctionReturn(0);
3099 }
3100 
3101 #undef __FUNCT__
3102 #define __FUNCT__ "MatGetRowMin_MPIAIJ"
3103 PetscErrorCode MatGetRowMin_MPIAIJ(Mat A, Vec v, PetscInt idx[])
3104 {
3105   Mat_MPIAIJ     *mat   = (Mat_MPIAIJ*) A->data;
3106   PetscInt       n      = A->rmap->n;
3107   PetscInt       cstart = A->cmap->rstart;
3108   PetscInt       *cmap  = mat->garray;
3109   PetscInt       *diagIdx, *offdiagIdx;
3110   Vec            diagV, offdiagV;
3111   PetscScalar    *a, *diagA, *offdiagA;
3112   PetscInt       r;
3113   PetscErrorCode ierr;
3114 
3115   PetscFunctionBegin;
3116   ierr = PetscMalloc2(n,PetscInt,&diagIdx,n,PetscInt,&offdiagIdx);CHKERRQ(ierr);
3117   ierr = VecCreateSeq(PetscObjectComm((PetscObject)A), n, &diagV);CHKERRQ(ierr);
3118   ierr = VecCreateSeq(PetscObjectComm((PetscObject)A), n, &offdiagV);CHKERRQ(ierr);
3119   ierr = MatGetRowMin(mat->A, diagV,    diagIdx);CHKERRQ(ierr);
3120   ierr = MatGetRowMin(mat->B, offdiagV, offdiagIdx);CHKERRQ(ierr);
3121   ierr = VecGetArray(v,        &a);CHKERRQ(ierr);
3122   ierr = VecGetArray(diagV,    &diagA);CHKERRQ(ierr);
3123   ierr = VecGetArray(offdiagV, &offdiagA);CHKERRQ(ierr);
3124   for (r = 0; r < n; ++r) {
3125     if (PetscAbsScalar(diagA[r]) <= PetscAbsScalar(offdiagA[r])) {
3126       a[r]   = diagA[r];
3127       idx[r] = cstart + diagIdx[r];
3128     } else {
3129       a[r]   = offdiagA[r];
3130       idx[r] = cmap[offdiagIdx[r]];
3131     }
3132   }
3133   ierr = VecRestoreArray(v,        &a);CHKERRQ(ierr);
3134   ierr = VecRestoreArray(diagV,    &diagA);CHKERRQ(ierr);
3135   ierr = VecRestoreArray(offdiagV, &offdiagA);CHKERRQ(ierr);
3136   ierr = VecDestroy(&diagV);CHKERRQ(ierr);
3137   ierr = VecDestroy(&offdiagV);CHKERRQ(ierr);
3138   ierr = PetscFree2(diagIdx, offdiagIdx);CHKERRQ(ierr);
3139   PetscFunctionReturn(0);
3140 }
3141 
3142 #undef __FUNCT__
3143 #define __FUNCT__ "MatGetRowMax_MPIAIJ"
3144 PetscErrorCode MatGetRowMax_MPIAIJ(Mat A, Vec v, PetscInt idx[])
3145 {
3146   Mat_MPIAIJ     *mat   = (Mat_MPIAIJ*) A->data;
3147   PetscInt       n      = A->rmap->n;
3148   PetscInt       cstart = A->cmap->rstart;
3149   PetscInt       *cmap  = mat->garray;
3150   PetscInt       *diagIdx, *offdiagIdx;
3151   Vec            diagV, offdiagV;
3152   PetscScalar    *a, *diagA, *offdiagA;
3153   PetscInt       r;
3154   PetscErrorCode ierr;
3155 
3156   PetscFunctionBegin;
3157   ierr = PetscMalloc2(n,PetscInt,&diagIdx,n,PetscInt,&offdiagIdx);CHKERRQ(ierr);
3158   ierr = VecCreateSeq(PETSC_COMM_SELF, n, &diagV);CHKERRQ(ierr);
3159   ierr = VecCreateSeq(PETSC_COMM_SELF, n, &offdiagV);CHKERRQ(ierr);
3160   ierr = MatGetRowMax(mat->A, diagV,    diagIdx);CHKERRQ(ierr);
3161   ierr = MatGetRowMax(mat->B, offdiagV, offdiagIdx);CHKERRQ(ierr);
3162   ierr = VecGetArray(v,        &a);CHKERRQ(ierr);
3163   ierr = VecGetArray(diagV,    &diagA);CHKERRQ(ierr);
3164   ierr = VecGetArray(offdiagV, &offdiagA);CHKERRQ(ierr);
3165   for (r = 0; r < n; ++r) {
3166     if (PetscAbsScalar(diagA[r]) >= PetscAbsScalar(offdiagA[r])) {
3167       a[r]   = diagA[r];
3168       idx[r] = cstart + diagIdx[r];
3169     } else {
3170       a[r]   = offdiagA[r];
3171       idx[r] = cmap[offdiagIdx[r]];
3172     }
3173   }
3174   ierr = VecRestoreArray(v,        &a);CHKERRQ(ierr);
3175   ierr = VecRestoreArray(diagV,    &diagA);CHKERRQ(ierr);
3176   ierr = VecRestoreArray(offdiagV, &offdiagA);CHKERRQ(ierr);
3177   ierr = VecDestroy(&diagV);CHKERRQ(ierr);
3178   ierr = VecDestroy(&offdiagV);CHKERRQ(ierr);
3179   ierr = PetscFree2(diagIdx, offdiagIdx);CHKERRQ(ierr);
3180   PetscFunctionReturn(0);
3181 }
3182 
3183 #undef __FUNCT__
3184 #define __FUNCT__ "MatGetSeqNonzeroStructure_MPIAIJ"
3185 PetscErrorCode MatGetSeqNonzeroStructure_MPIAIJ(Mat mat,Mat *newmat)
3186 {
3187   PetscErrorCode ierr;
3188   Mat            *dummy;
3189 
3190   PetscFunctionBegin;
3191   ierr    = MatGetSubMatrix_MPIAIJ_All(mat,MAT_DO_NOT_GET_VALUES,MAT_INITIAL_MATRIX,&dummy);CHKERRQ(ierr);
3192   *newmat = *dummy;
3193   ierr    = PetscFree(dummy);CHKERRQ(ierr);
3194   PetscFunctionReturn(0);
3195 }
3196 
3197 extern PetscErrorCode  MatFDColoringApply_AIJ(Mat,MatFDColoring,Vec,MatStructure*,void*);
3198 
3199 #undef __FUNCT__
3200 #define __FUNCT__ "MatInvertBlockDiagonal_MPIAIJ"
3201 PetscErrorCode  MatInvertBlockDiagonal_MPIAIJ(Mat A,const PetscScalar **values)
3202 {
3203   Mat_MPIAIJ     *a = (Mat_MPIAIJ*) A->data;
3204   PetscErrorCode ierr;
3205 
3206   PetscFunctionBegin;
3207   ierr = MatInvertBlockDiagonal(a->A,values);CHKERRQ(ierr);
3208   PetscFunctionReturn(0);
3209 }
3210 
3211 #undef __FUNCT__
3212 #define __FUNCT__ "MatSetRandom_MPIAIJ"
3213 static PetscErrorCode  MatSetRandom_MPIAIJ(Mat x,PetscRandom rctx)
3214 {
3215   PetscErrorCode ierr;
3216   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)x->data;
3217 
3218   PetscFunctionBegin;
3219   ierr = MatSetRandom(aij->A,rctx);CHKERRQ(ierr);
3220   ierr = MatSetRandom(aij->B,rctx);CHKERRQ(ierr);
3221   ierr = MatAssemblyBegin(x,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
3222   ierr = MatAssemblyEnd(x,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
3223   PetscFunctionReturn(0);
3224 }
3225 
3226 /* -------------------------------------------------------------------*/
3227 static struct _MatOps MatOps_Values = {MatSetValues_MPIAIJ,
3228                                        MatGetRow_MPIAIJ,
3229                                        MatRestoreRow_MPIAIJ,
3230                                        MatMult_MPIAIJ,
3231                                 /* 4*/ MatMultAdd_MPIAIJ,
3232                                        MatMultTranspose_MPIAIJ,
3233                                        MatMultTransposeAdd_MPIAIJ,
3234 #if defined(PETSC_HAVE_PBGL)
3235                                        MatSolve_MPIAIJ,
3236 #else
3237                                        0,
3238 #endif
3239                                        0,
3240                                        0,
3241                                 /*10*/ 0,
3242                                        0,
3243                                        0,
3244                                        MatSOR_MPIAIJ,
3245                                        MatTranspose_MPIAIJ,
3246                                 /*15*/ MatGetInfo_MPIAIJ,
3247                                        MatEqual_MPIAIJ,
3248                                        MatGetDiagonal_MPIAIJ,
3249                                        MatDiagonalScale_MPIAIJ,
3250                                        MatNorm_MPIAIJ,
3251                                 /*20*/ MatAssemblyBegin_MPIAIJ,
3252                                        MatAssemblyEnd_MPIAIJ,
3253                                        MatSetOption_MPIAIJ,
3254                                        MatZeroEntries_MPIAIJ,
3255                                 /*24*/ MatZeroRows_MPIAIJ,
3256                                        0,
3257 #if defined(PETSC_HAVE_PBGL)
3258                                        0,
3259 #else
3260                                        0,
3261 #endif
3262                                        0,
3263                                        0,
3264                                 /*29*/ MatSetUp_MPIAIJ,
3265 #if defined(PETSC_HAVE_PBGL)
3266                                        0,
3267 #else
3268                                        0,
3269 #endif
3270                                        0,
3271                                        0,
3272                                        0,
3273                                 /*34*/ MatDuplicate_MPIAIJ,
3274                                        0,
3275                                        0,
3276                                        0,
3277                                        0,
3278                                 /*39*/ MatAXPY_MPIAIJ,
3279                                        MatGetSubMatrices_MPIAIJ,
3280                                        MatIncreaseOverlap_MPIAIJ,
3281                                        MatGetValues_MPIAIJ,
3282                                        MatCopy_MPIAIJ,
3283                                 /*44*/ MatGetRowMax_MPIAIJ,
3284                                        MatScale_MPIAIJ,
3285                                        0,
3286                                        0,
3287                                        MatZeroRowsColumns_MPIAIJ,
3288                                 /*49*/ MatSetRandom_MPIAIJ,
3289                                        0,
3290                                        0,
3291                                        0,
3292                                        0,
3293                                 /*54*/ MatFDColoringCreate_MPIAIJ,
3294                                        0,
3295                                        MatSetUnfactored_MPIAIJ,
3296                                        MatPermute_MPIAIJ,
3297                                        0,
3298                                 /*59*/ MatGetSubMatrix_MPIAIJ,
3299                                        MatDestroy_MPIAIJ,
3300                                        MatView_MPIAIJ,
3301                                        0,
3302                                        MatMatMatMult_MPIAIJ_MPIAIJ_MPIAIJ,
3303                                 /*64*/ MatMatMatMultSymbolic_MPIAIJ_MPIAIJ_MPIAIJ,
3304                                        MatMatMatMultNumeric_MPIAIJ_MPIAIJ_MPIAIJ,
3305                                        0,
3306                                        0,
3307                                        0,
3308                                 /*69*/ MatGetRowMaxAbs_MPIAIJ,
3309                                        MatGetRowMinAbs_MPIAIJ,
3310                                        0,
3311                                        MatSetColoring_MPIAIJ,
3312                                        0,
3313                                        MatSetValuesAdifor_MPIAIJ,
3314                                 /*75*/ MatFDColoringApply_AIJ,
3315                                        0,
3316                                        0,
3317                                        0,
3318                                        MatFindZeroDiagonals_MPIAIJ,
3319                                 /*80*/ 0,
3320                                        0,
3321                                        0,
3322                                 /*83*/ MatLoad_MPIAIJ,
3323                                        0,
3324                                        0,
3325                                        0,
3326                                        0,
3327                                        0,
3328                                 /*89*/ MatMatMult_MPIAIJ_MPIAIJ,
3329                                        MatMatMultSymbolic_MPIAIJ_MPIAIJ,
3330                                        MatMatMultNumeric_MPIAIJ_MPIAIJ,
3331                                        MatPtAP_MPIAIJ_MPIAIJ,
3332                                        MatPtAPSymbolic_MPIAIJ_MPIAIJ,
3333                                 /*94*/ MatPtAPNumeric_MPIAIJ_MPIAIJ,
3334                                        0,
3335                                        0,
3336                                        0,
3337                                        0,
3338                                 /*99*/ 0,
3339                                        0,
3340                                        0,
3341                                        MatConjugate_MPIAIJ,
3342                                        0,
3343                                 /*104*/MatSetValuesRow_MPIAIJ,
3344                                        MatRealPart_MPIAIJ,
3345                                        MatImaginaryPart_MPIAIJ,
3346                                        0,
3347                                        0,
3348                                 /*109*/0,
3349                                        MatGetRedundantMatrix_MPIAIJ,
3350                                        MatGetRowMin_MPIAIJ,
3351                                        0,
3352                                        0,
3353                                 /*114*/MatGetSeqNonzeroStructure_MPIAIJ,
3354                                        0,
3355                                        0,
3356                                        0,
3357                                        0,
3358                                 /*119*/0,
3359                                        0,
3360                                        0,
3361                                        0,
3362                                        MatGetMultiProcBlock_MPIAIJ,
3363                                 /*124*/MatFindNonzeroRows_MPIAIJ,
3364                                        MatGetColumnNorms_MPIAIJ,
3365                                        MatInvertBlockDiagonal_MPIAIJ,
3366                                        0,
3367                                        MatGetSubMatricesParallel_MPIAIJ,
3368                                 /*129*/0,
3369                                        MatTransposeMatMult_MPIAIJ_MPIAIJ,
3370                                        MatTransposeMatMultSymbolic_MPIAIJ_MPIAIJ,
3371                                        MatTransposeMatMultNumeric_MPIAIJ_MPIAIJ,
3372                                        0,
3373                                 /*134*/0,
3374                                        0,
3375                                        0,
3376                                        0,
3377                                        0,
3378                                 /*139*/0,
3379                                        0
3380 };
3381 
3382 /* ----------------------------------------------------------------------------------------*/
3383 
3384 #undef __FUNCT__
3385 #define __FUNCT__ "MatStoreValues_MPIAIJ"
3386 PetscErrorCode  MatStoreValues_MPIAIJ(Mat mat)
3387 {
3388   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
3389   PetscErrorCode ierr;
3390 
3391   PetscFunctionBegin;
3392   ierr = MatStoreValues(aij->A);CHKERRQ(ierr);
3393   ierr = MatStoreValues(aij->B);CHKERRQ(ierr);
3394   PetscFunctionReturn(0);
3395 }
3396 
3397 #undef __FUNCT__
3398 #define __FUNCT__ "MatRetrieveValues_MPIAIJ"
3399 PetscErrorCode  MatRetrieveValues_MPIAIJ(Mat mat)
3400 {
3401   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
3402   PetscErrorCode ierr;
3403 
3404   PetscFunctionBegin;
3405   ierr = MatRetrieveValues(aij->A);CHKERRQ(ierr);
3406   ierr = MatRetrieveValues(aij->B);CHKERRQ(ierr);
3407   PetscFunctionReturn(0);
3408 }
3409 
3410 #undef __FUNCT__
3411 #define __FUNCT__ "MatMPIAIJSetPreallocation_MPIAIJ"
3412 PetscErrorCode  MatMPIAIJSetPreallocation_MPIAIJ(Mat B,PetscInt d_nz,const PetscInt d_nnz[],PetscInt o_nz,const PetscInt o_nnz[])
3413 {
3414   Mat_MPIAIJ     *b;
3415   PetscErrorCode ierr;
3416 
3417   PetscFunctionBegin;
3418   ierr = PetscLayoutSetUp(B->rmap);CHKERRQ(ierr);
3419   ierr = PetscLayoutSetUp(B->cmap);CHKERRQ(ierr);
3420   b = (Mat_MPIAIJ*)B->data;
3421 
3422   if (!B->preallocated) {
3423     /* Explicitly create 2 MATSEQAIJ matrices. */
3424     ierr = MatCreate(PETSC_COMM_SELF,&b->A);CHKERRQ(ierr);
3425     ierr = MatSetSizes(b->A,B->rmap->n,B->cmap->n,B->rmap->n,B->cmap->n);CHKERRQ(ierr);
3426     ierr = MatSetBlockSizes(b->A,B->rmap->bs,B->cmap->bs);CHKERRQ(ierr);
3427     ierr = MatSetType(b->A,MATSEQAIJ);CHKERRQ(ierr);
3428     ierr = PetscLogObjectParent(B,b->A);CHKERRQ(ierr);
3429     ierr = MatCreate(PETSC_COMM_SELF,&b->B);CHKERRQ(ierr);
3430     ierr = MatSetSizes(b->B,B->rmap->n,B->cmap->N,B->rmap->n,B->cmap->N);CHKERRQ(ierr);
3431     ierr = MatSetBlockSizes(b->B,B->rmap->bs,B->cmap->bs);CHKERRQ(ierr);
3432     ierr = MatSetType(b->B,MATSEQAIJ);CHKERRQ(ierr);
3433     ierr = PetscLogObjectParent(B,b->B);CHKERRQ(ierr);
3434   }
3435 
3436   ierr = MatSeqAIJSetPreallocation(b->A,d_nz,d_nnz);CHKERRQ(ierr);
3437   ierr = MatSeqAIJSetPreallocation(b->B,o_nz,o_nnz);CHKERRQ(ierr);
3438   B->preallocated = PETSC_TRUE;
3439   PetscFunctionReturn(0);
3440 }
3441 
3442 #undef __FUNCT__
3443 #define __FUNCT__ "MatDuplicate_MPIAIJ"
3444 PetscErrorCode MatDuplicate_MPIAIJ(Mat matin,MatDuplicateOption cpvalues,Mat *newmat)
3445 {
3446   Mat            mat;
3447   Mat_MPIAIJ     *a,*oldmat = (Mat_MPIAIJ*)matin->data;
3448   PetscErrorCode ierr;
3449 
3450   PetscFunctionBegin;
3451   *newmat = 0;
3452   ierr    = MatCreate(PetscObjectComm((PetscObject)matin),&mat);CHKERRQ(ierr);
3453   ierr    = MatSetSizes(mat,matin->rmap->n,matin->cmap->n,matin->rmap->N,matin->cmap->N);CHKERRQ(ierr);
3454   ierr    = MatSetBlockSizes(mat,matin->rmap->bs,matin->cmap->bs);CHKERRQ(ierr);
3455   ierr    = MatSetType(mat,((PetscObject)matin)->type_name);CHKERRQ(ierr);
3456   ierr    = PetscMemcpy(mat->ops,matin->ops,sizeof(struct _MatOps));CHKERRQ(ierr);
3457   a       = (Mat_MPIAIJ*)mat->data;
3458 
3459   mat->factortype   = matin->factortype;
3460   mat->rmap->bs     = matin->rmap->bs;
3461   mat->cmap->bs     = matin->cmap->bs;
3462   mat->assembled    = PETSC_TRUE;
3463   mat->insertmode   = NOT_SET_VALUES;
3464   mat->preallocated = PETSC_TRUE;
3465 
3466   a->size         = oldmat->size;
3467   a->rank         = oldmat->rank;
3468   a->donotstash   = oldmat->donotstash;
3469   a->roworiented  = oldmat->roworiented;
3470   a->rowindices   = 0;
3471   a->rowvalues    = 0;
3472   a->getrowactive = PETSC_FALSE;
3473 
3474   ierr = PetscLayoutReference(matin->rmap,&mat->rmap);CHKERRQ(ierr);
3475   ierr = PetscLayoutReference(matin->cmap,&mat->cmap);CHKERRQ(ierr);
3476 
3477   if (oldmat->colmap) {
3478 #if defined(PETSC_USE_CTABLE)
3479     ierr = PetscTableCreateCopy(oldmat->colmap,&a->colmap);CHKERRQ(ierr);
3480 #else
3481     ierr = PetscMalloc((mat->cmap->N)*sizeof(PetscInt),&a->colmap);CHKERRQ(ierr);
3482     ierr = PetscLogObjectMemory(mat,(mat->cmap->N)*sizeof(PetscInt));CHKERRQ(ierr);
3483     ierr = PetscMemcpy(a->colmap,oldmat->colmap,(mat->cmap->N)*sizeof(PetscInt));CHKERRQ(ierr);
3484 #endif
3485   } else a->colmap = 0;
3486   if (oldmat->garray) {
3487     PetscInt len;
3488     len  = oldmat->B->cmap->n;
3489     ierr = PetscMalloc((len+1)*sizeof(PetscInt),&a->garray);CHKERRQ(ierr);
3490     ierr = PetscLogObjectMemory(mat,len*sizeof(PetscInt));CHKERRQ(ierr);
3491     if (len) { ierr = PetscMemcpy(a->garray,oldmat->garray,len*sizeof(PetscInt));CHKERRQ(ierr); }
3492   } else a->garray = 0;
3493 
3494   ierr    = VecDuplicate(oldmat->lvec,&a->lvec);CHKERRQ(ierr);
3495   ierr    = PetscLogObjectParent(mat,a->lvec);CHKERRQ(ierr);
3496   ierr    = VecScatterCopy(oldmat->Mvctx,&a->Mvctx);CHKERRQ(ierr);
3497   ierr    = PetscLogObjectParent(mat,a->Mvctx);CHKERRQ(ierr);
3498   ierr    = MatDuplicate(oldmat->A,cpvalues,&a->A);CHKERRQ(ierr);
3499   ierr    = PetscLogObjectParent(mat,a->A);CHKERRQ(ierr);
3500   ierr    = MatDuplicate(oldmat->B,cpvalues,&a->B);CHKERRQ(ierr);
3501   ierr    = PetscLogObjectParent(mat,a->B);CHKERRQ(ierr);
3502   ierr    = PetscFunctionListDuplicate(((PetscObject)matin)->qlist,&((PetscObject)mat)->qlist);CHKERRQ(ierr);
3503   *newmat = mat;
3504   PetscFunctionReturn(0);
3505 }
3506 
3507 
3508 
3509 #undef __FUNCT__
3510 #define __FUNCT__ "MatLoad_MPIAIJ"
3511 PetscErrorCode MatLoad_MPIAIJ(Mat newMat, PetscViewer viewer)
3512 {
3513   PetscScalar    *vals,*svals;
3514   MPI_Comm       comm;
3515   PetscErrorCode ierr;
3516   PetscMPIInt    rank,size,tag = ((PetscObject)viewer)->tag;
3517   PetscInt       i,nz,j,rstart,rend,mmax,maxnz = 0,grows,gcols;
3518   PetscInt       header[4],*rowlengths = 0,M,N,m,*cols;
3519   PetscInt       *ourlens = NULL,*procsnz = NULL,*offlens = NULL,jj,*mycols,*smycols;
3520   PetscInt       cend,cstart,n,*rowners,sizesset=1;
3521   int            fd;
3522   PetscInt       bs = 1;
3523 
3524   PetscFunctionBegin;
3525   ierr = PetscObjectGetComm((PetscObject)viewer,&comm);CHKERRQ(ierr);
3526   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
3527   ierr = MPI_Comm_rank(comm,&rank);CHKERRQ(ierr);
3528   if (!rank) {
3529     ierr = PetscViewerBinaryGetDescriptor(viewer,&fd);CHKERRQ(ierr);
3530     ierr = PetscBinaryRead(fd,(char*)header,4,PETSC_INT);CHKERRQ(ierr);
3531     if (header[0] != MAT_FILE_CLASSID) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_FILE_UNEXPECTED,"not matrix object");
3532   }
3533 
3534   ierr = PetscOptionsBegin(comm,NULL,"Options for loading SEQAIJ matrix","Mat");CHKERRQ(ierr);
3535   ierr = PetscOptionsInt("-matload_block_size","Set the blocksize used to store the matrix","MatLoad",bs,&bs,NULL);CHKERRQ(ierr);
3536   ierr = PetscOptionsEnd();CHKERRQ(ierr);
3537 
3538   if (newMat->rmap->n < 0 && newMat->rmap->N < 0 && newMat->cmap->n < 0 && newMat->cmap->N < 0) sizesset = 0;
3539 
3540   ierr = MPI_Bcast(header+1,3,MPIU_INT,0,comm);CHKERRQ(ierr);
3541   M    = header[1]; N = header[2];
3542   /* If global rows/cols are set to PETSC_DECIDE, set it to the sizes given in the file */
3543   if (sizesset && newMat->rmap->N < 0) newMat->rmap->N = M;
3544   if (sizesset && newMat->cmap->N < 0) newMat->cmap->N = N;
3545 
3546   /* If global sizes are set, check if they are consistent with that given in the file */
3547   if (sizesset) {
3548     ierr = MatGetSize(newMat,&grows,&gcols);CHKERRQ(ierr);
3549   }
3550   if (sizesset && newMat->rmap->N != grows) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_FILE_UNEXPECTED, "Inconsistent # of rows:Matrix in file has (%d) and input matrix has (%d)",M,grows);
3551   if (sizesset && newMat->cmap->N != gcols) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_FILE_UNEXPECTED, "Inconsistent # of cols:Matrix in file has (%d) and input matrix has (%d)",N,gcols);
3552 
3553   /* determine ownership of all (block) rows */
3554   if (M%bs) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_FILE_UNEXPECTED, "Inconsistent # of rows (%d) and block size (%d)",M,bs);
3555   if (newMat->rmap->n < 0) m = bs*((M/bs)/size + (((M/bs) % size) > rank));    /* PETSC_DECIDE */
3556   else m = newMat->rmap->n; /* Set by user */
3557 
3558   ierr = PetscMalloc((size+1)*sizeof(PetscInt),&rowners);CHKERRQ(ierr);
3559   ierr = MPI_Allgather(&m,1,MPIU_INT,rowners+1,1,MPIU_INT,comm);CHKERRQ(ierr);
3560 
3561   /* First process needs enough room for process with most rows */
3562   if (!rank) {
3563     mmax = rowners[1];
3564     for (i=2; i<=size; i++) {
3565       mmax = PetscMax(mmax, rowners[i]);
3566     }
3567   } else mmax = -1;             /* unused, but compilers complain */
3568 
3569   rowners[0] = 0;
3570   for (i=2; i<=size; i++) {
3571     rowners[i] += rowners[i-1];
3572   }
3573   rstart = rowners[rank];
3574   rend   = rowners[rank+1];
3575 
3576   /* distribute row lengths to all processors */
3577   ierr = PetscMalloc2(m,PetscInt,&ourlens,m,PetscInt,&offlens);CHKERRQ(ierr);
3578   if (!rank) {
3579     ierr = PetscBinaryRead(fd,ourlens,m,PETSC_INT);CHKERRQ(ierr);
3580     ierr = PetscMalloc(mmax*sizeof(PetscInt),&rowlengths);CHKERRQ(ierr);
3581     ierr = PetscMalloc(size*sizeof(PetscInt),&procsnz);CHKERRQ(ierr);
3582     ierr = PetscMemzero(procsnz,size*sizeof(PetscInt));CHKERRQ(ierr);
3583     for (j=0; j<m; j++) {
3584       procsnz[0] += ourlens[j];
3585     }
3586     for (i=1; i<size; i++) {
3587       ierr = PetscBinaryRead(fd,rowlengths,rowners[i+1]-rowners[i],PETSC_INT);CHKERRQ(ierr);
3588       /* calculate the number of nonzeros on each processor */
3589       for (j=0; j<rowners[i+1]-rowners[i]; j++) {
3590         procsnz[i] += rowlengths[j];
3591       }
3592       ierr = MPIULong_Send(rowlengths,rowners[i+1]-rowners[i],MPIU_INT,i,tag,comm);CHKERRQ(ierr);
3593     }
3594     ierr = PetscFree(rowlengths);CHKERRQ(ierr);
3595   } else {
3596     ierr = MPIULong_Recv(ourlens,m,MPIU_INT,0,tag,comm);CHKERRQ(ierr);
3597   }
3598 
3599   if (!rank) {
3600     /* determine max buffer needed and allocate it */
3601     maxnz = 0;
3602     for (i=0; i<size; i++) {
3603       maxnz = PetscMax(maxnz,procsnz[i]);
3604     }
3605     ierr = PetscMalloc(maxnz*sizeof(PetscInt),&cols);CHKERRQ(ierr);
3606 
3607     /* read in my part of the matrix column indices  */
3608     nz   = procsnz[0];
3609     ierr = PetscMalloc(nz*sizeof(PetscInt),&mycols);CHKERRQ(ierr);
3610     ierr = PetscBinaryRead(fd,mycols,nz,PETSC_INT);CHKERRQ(ierr);
3611 
3612     /* read in every one elses and ship off */
3613     for (i=1; i<size; i++) {
3614       nz   = procsnz[i];
3615       ierr = PetscBinaryRead(fd,cols,nz,PETSC_INT);CHKERRQ(ierr);
3616       ierr = MPIULong_Send(cols,nz,MPIU_INT,i,tag,comm);CHKERRQ(ierr);
3617     }
3618     ierr = PetscFree(cols);CHKERRQ(ierr);
3619   } else {
3620     /* determine buffer space needed for message */
3621     nz = 0;
3622     for (i=0; i<m; i++) {
3623       nz += ourlens[i];
3624     }
3625     ierr = PetscMalloc(nz*sizeof(PetscInt),&mycols);CHKERRQ(ierr);
3626 
3627     /* receive message of column indices*/
3628     ierr = MPIULong_Recv(mycols,nz,MPIU_INT,0,tag,comm);CHKERRQ(ierr);
3629   }
3630 
3631   /* determine column ownership if matrix is not square */
3632   if (N != M) {
3633     if (newMat->cmap->n < 0) n = N/size + ((N % size) > rank);
3634     else n = newMat->cmap->n;
3635     ierr   = MPI_Scan(&n,&cend,1,MPIU_INT,MPI_SUM,comm);CHKERRQ(ierr);
3636     cstart = cend - n;
3637   } else {
3638     cstart = rstart;
3639     cend   = rend;
3640     n      = cend - cstart;
3641   }
3642 
3643   /* loop over local rows, determining number of off diagonal entries */
3644   ierr = PetscMemzero(offlens,m*sizeof(PetscInt));CHKERRQ(ierr);
3645   jj   = 0;
3646   for (i=0; i<m; i++) {
3647     for (j=0; j<ourlens[i]; j++) {
3648       if (mycols[jj] < cstart || mycols[jj] >= cend) offlens[i]++;
3649       jj++;
3650     }
3651   }
3652 
3653   for (i=0; i<m; i++) {
3654     ourlens[i] -= offlens[i];
3655   }
3656   if (!sizesset) {
3657     ierr = MatSetSizes(newMat,m,n,M,N);CHKERRQ(ierr);
3658   }
3659 
3660   if (bs > 1) {ierr = MatSetBlockSize(newMat,bs);CHKERRQ(ierr);}
3661 
3662   ierr = MatMPIAIJSetPreallocation(newMat,0,ourlens,0,offlens);CHKERRQ(ierr);
3663 
3664   for (i=0; i<m; i++) {
3665     ourlens[i] += offlens[i];
3666   }
3667 
3668   if (!rank) {
3669     ierr = PetscMalloc((maxnz+1)*sizeof(PetscScalar),&vals);CHKERRQ(ierr);
3670 
3671     /* read in my part of the matrix numerical values  */
3672     nz   = procsnz[0];
3673     ierr = PetscBinaryRead(fd,vals,nz,PETSC_SCALAR);CHKERRQ(ierr);
3674 
3675     /* insert into matrix */
3676     jj      = rstart;
3677     smycols = mycols;
3678     svals   = vals;
3679     for (i=0; i<m; i++) {
3680       ierr     = MatSetValues_MPIAIJ(newMat,1,&jj,ourlens[i],smycols,svals,INSERT_VALUES);CHKERRQ(ierr);
3681       smycols += ourlens[i];
3682       svals   += ourlens[i];
3683       jj++;
3684     }
3685 
3686     /* read in other processors and ship out */
3687     for (i=1; i<size; i++) {
3688       nz   = procsnz[i];
3689       ierr = PetscBinaryRead(fd,vals,nz,PETSC_SCALAR);CHKERRQ(ierr);
3690       ierr = MPIULong_Send(vals,nz,MPIU_SCALAR,i,((PetscObject)newMat)->tag,comm);CHKERRQ(ierr);
3691     }
3692     ierr = PetscFree(procsnz);CHKERRQ(ierr);
3693   } else {
3694     /* receive numeric values */
3695     ierr = PetscMalloc((nz+1)*sizeof(PetscScalar),&vals);CHKERRQ(ierr);
3696 
3697     /* receive message of values*/
3698     ierr = MPIULong_Recv(vals,nz,MPIU_SCALAR,0,((PetscObject)newMat)->tag,comm);CHKERRQ(ierr);
3699 
3700     /* insert into matrix */
3701     jj      = rstart;
3702     smycols = mycols;
3703     svals   = vals;
3704     for (i=0; i<m; i++) {
3705       ierr     = MatSetValues_MPIAIJ(newMat,1,&jj,ourlens[i],smycols,svals,INSERT_VALUES);CHKERRQ(ierr);
3706       smycols += ourlens[i];
3707       svals   += ourlens[i];
3708       jj++;
3709     }
3710   }
3711   ierr = PetscFree2(ourlens,offlens);CHKERRQ(ierr);
3712   ierr = PetscFree(vals);CHKERRQ(ierr);
3713   ierr = PetscFree(mycols);CHKERRQ(ierr);
3714   ierr = PetscFree(rowners);CHKERRQ(ierr);
3715   ierr = MatAssemblyBegin(newMat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
3716   ierr = MatAssemblyEnd(newMat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
3717   PetscFunctionReturn(0);
3718 }
3719 
3720 #undef __FUNCT__
3721 #define __FUNCT__ "MatGetSubMatrix_MPIAIJ"
3722 PetscErrorCode MatGetSubMatrix_MPIAIJ(Mat mat,IS isrow,IS iscol,MatReuse call,Mat *newmat)
3723 {
3724   PetscErrorCode ierr;
3725   IS             iscol_local;
3726   PetscInt       csize;
3727 
3728   PetscFunctionBegin;
3729   ierr = ISGetLocalSize(iscol,&csize);CHKERRQ(ierr);
3730   if (call == MAT_REUSE_MATRIX) {
3731     ierr = PetscObjectQuery((PetscObject)*newmat,"ISAllGather",(PetscObject*)&iscol_local);CHKERRQ(ierr);
3732     if (!iscol_local) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"Submatrix passed in was not used before, cannot reuse");
3733   } else {
3734     PetscInt cbs;
3735     ierr = ISGetBlockSize(iscol,&cbs);CHKERRQ(ierr);
3736     ierr = ISAllGather(iscol,&iscol_local);CHKERRQ(ierr);
3737     ierr = ISSetBlockSize(iscol_local,cbs);CHKERRQ(ierr);
3738   }
3739   ierr = MatGetSubMatrix_MPIAIJ_Private(mat,isrow,iscol_local,csize,call,newmat);CHKERRQ(ierr);
3740   if (call == MAT_INITIAL_MATRIX) {
3741     ierr = PetscObjectCompose((PetscObject)*newmat,"ISAllGather",(PetscObject)iscol_local);CHKERRQ(ierr);
3742     ierr = ISDestroy(&iscol_local);CHKERRQ(ierr);
3743   }
3744   PetscFunctionReturn(0);
3745 }
3746 
3747 extern PetscErrorCode MatGetSubMatrices_MPIAIJ_Local(Mat,PetscInt,const IS[],const IS[],MatReuse,PetscBool*,Mat*);
3748 #undef __FUNCT__
3749 #define __FUNCT__ "MatGetSubMatrix_MPIAIJ_Private"
3750 /*
3751     Not great since it makes two copies of the submatrix, first an SeqAIJ
3752   in local and then by concatenating the local matrices the end result.
3753   Writing it directly would be much like MatGetSubMatrices_MPIAIJ()
3754 
3755   Note: This requires a sequential iscol with all indices.
3756 */
3757 PetscErrorCode MatGetSubMatrix_MPIAIJ_Private(Mat mat,IS isrow,IS iscol,PetscInt csize,MatReuse call,Mat *newmat)
3758 {
3759   PetscErrorCode ierr;
3760   PetscMPIInt    rank,size;
3761   PetscInt       i,m,n,rstart,row,rend,nz,*cwork,j,bs,cbs;
3762   PetscInt       *ii,*jj,nlocal,*dlens,*olens,dlen,olen,jend,mglobal,ncol;
3763   PetscBool      allcolumns, colflag;
3764   Mat            M,Mreuse;
3765   MatScalar      *vwork,*aa;
3766   MPI_Comm       comm;
3767   Mat_SeqAIJ     *aij;
3768 
3769   PetscFunctionBegin;
3770   ierr = PetscObjectGetComm((PetscObject)mat,&comm);CHKERRQ(ierr);
3771   ierr = MPI_Comm_rank(comm,&rank);CHKERRQ(ierr);
3772   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
3773 
3774   ierr = ISIdentity(iscol,&colflag);CHKERRQ(ierr);
3775   ierr = ISGetLocalSize(iscol,&ncol);CHKERRQ(ierr);
3776   if (colflag && ncol == mat->cmap->N) {
3777     allcolumns = PETSC_TRUE;
3778   } else {
3779     allcolumns = PETSC_FALSE;
3780   }
3781   if (call ==  MAT_REUSE_MATRIX) {
3782     ierr = PetscObjectQuery((PetscObject)*newmat,"SubMatrix",(PetscObject*)&Mreuse);CHKERRQ(ierr);
3783     if (!Mreuse) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"Submatrix passed in was not used before, cannot reuse");
3784     ierr = MatGetSubMatrices_MPIAIJ_Local(mat,1,&isrow,&iscol,MAT_REUSE_MATRIX,&allcolumns,&Mreuse);CHKERRQ(ierr);
3785   } else {
3786     ierr = MatGetSubMatrices_MPIAIJ_Local(mat,1,&isrow,&iscol,MAT_INITIAL_MATRIX,&allcolumns,&Mreuse);CHKERRQ(ierr);
3787   }
3788 
3789   /*
3790       m - number of local rows
3791       n - number of columns (same on all processors)
3792       rstart - first row in new global matrix generated
3793   */
3794   ierr = MatGetSize(Mreuse,&m,&n);CHKERRQ(ierr);
3795   ierr = MatGetBlockSizes(Mreuse,&bs,&cbs);CHKERRQ(ierr);
3796   if (call == MAT_INITIAL_MATRIX) {
3797     aij = (Mat_SeqAIJ*)(Mreuse)->data;
3798     ii  = aij->i;
3799     jj  = aij->j;
3800 
3801     /*
3802         Determine the number of non-zeros in the diagonal and off-diagonal
3803         portions of the matrix in order to do correct preallocation
3804     */
3805 
3806     /* first get start and end of "diagonal" columns */
3807     if (csize == PETSC_DECIDE) {
3808       ierr = ISGetSize(isrow,&mglobal);CHKERRQ(ierr);
3809       if (mglobal == n) { /* square matrix */
3810         nlocal = m;
3811       } else {
3812         nlocal = n/size + ((n % size) > rank);
3813       }
3814     } else {
3815       nlocal = csize;
3816     }
3817     ierr   = MPI_Scan(&nlocal,&rend,1,MPIU_INT,MPI_SUM,comm);CHKERRQ(ierr);
3818     rstart = rend - nlocal;
3819     if (rank == size - 1 && rend != n) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_SIZ,"Local column sizes %D do not add up to total number of columns %D",rend,n);
3820 
3821     /* next, compute all the lengths */
3822     ierr  = PetscMalloc((2*m+1)*sizeof(PetscInt),&dlens);CHKERRQ(ierr);
3823     olens = dlens + m;
3824     for (i=0; i<m; i++) {
3825       jend = ii[i+1] - ii[i];
3826       olen = 0;
3827       dlen = 0;
3828       for (j=0; j<jend; j++) {
3829         if (*jj < rstart || *jj >= rend) olen++;
3830         else dlen++;
3831         jj++;
3832       }
3833       olens[i] = olen;
3834       dlens[i] = dlen;
3835     }
3836     ierr = MatCreate(comm,&M);CHKERRQ(ierr);
3837     ierr = MatSetSizes(M,m,nlocal,PETSC_DECIDE,n);CHKERRQ(ierr);
3838     ierr = MatSetBlockSizes(M,bs,cbs);CHKERRQ(ierr);
3839     ierr = MatSetType(M,((PetscObject)mat)->type_name);CHKERRQ(ierr);
3840     ierr = MatMPIAIJSetPreallocation(M,0,dlens,0,olens);CHKERRQ(ierr);
3841     ierr = PetscFree(dlens);CHKERRQ(ierr);
3842   } else {
3843     PetscInt ml,nl;
3844 
3845     M    = *newmat;
3846     ierr = MatGetLocalSize(M,&ml,&nl);CHKERRQ(ierr);
3847     if (ml != m) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_SIZ,"Previous matrix must be same size/layout as request");
3848     ierr = MatZeroEntries(M);CHKERRQ(ierr);
3849     /*
3850          The next two lines are needed so we may call MatSetValues_MPIAIJ() below directly,
3851        rather than the slower MatSetValues().
3852     */
3853     M->was_assembled = PETSC_TRUE;
3854     M->assembled     = PETSC_FALSE;
3855   }
3856   ierr = MatGetOwnershipRange(M,&rstart,&rend);CHKERRQ(ierr);
3857   aij  = (Mat_SeqAIJ*)(Mreuse)->data;
3858   ii   = aij->i;
3859   jj   = aij->j;
3860   aa   = aij->a;
3861   for (i=0; i<m; i++) {
3862     row   = rstart + i;
3863     nz    = ii[i+1] - ii[i];
3864     cwork = jj;     jj += nz;
3865     vwork = aa;     aa += nz;
3866     ierr  = MatSetValues_MPIAIJ(M,1,&row,nz,cwork,vwork,INSERT_VALUES);CHKERRQ(ierr);
3867   }
3868 
3869   ierr    = MatAssemblyBegin(M,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
3870   ierr    = MatAssemblyEnd(M,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
3871   *newmat = M;
3872 
3873   /* save submatrix used in processor for next request */
3874   if (call ==  MAT_INITIAL_MATRIX) {
3875     ierr = PetscObjectCompose((PetscObject)M,"SubMatrix",(PetscObject)Mreuse);CHKERRQ(ierr);
3876     ierr = MatDestroy(&Mreuse);CHKERRQ(ierr);
3877   }
3878   PetscFunctionReturn(0);
3879 }
3880 
3881 #undef __FUNCT__
3882 #define __FUNCT__ "MatMPIAIJSetPreallocationCSR_MPIAIJ"
3883 PetscErrorCode  MatMPIAIJSetPreallocationCSR_MPIAIJ(Mat B,const PetscInt Ii[],const PetscInt J[],const PetscScalar v[])
3884 {
3885   PetscInt       m,cstart, cend,j,nnz,i,d;
3886   PetscInt       *d_nnz,*o_nnz,nnz_max = 0,rstart,ii;
3887   const PetscInt *JJ;
3888   PetscScalar    *values;
3889   PetscErrorCode ierr;
3890 
3891   PetscFunctionBegin;
3892   if (Ii[0]) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Ii[0] must be 0 it is %D",Ii[0]);
3893 
3894   ierr   = PetscLayoutSetUp(B->rmap);CHKERRQ(ierr);
3895   ierr   = PetscLayoutSetUp(B->cmap);CHKERRQ(ierr);
3896   m      = B->rmap->n;
3897   cstart = B->cmap->rstart;
3898   cend   = B->cmap->rend;
3899   rstart = B->rmap->rstart;
3900 
3901   ierr = PetscMalloc2(m,PetscInt,&d_nnz,m,PetscInt,&o_nnz);CHKERRQ(ierr);
3902 
3903 #if defined(PETSC_USE_DEBUGGING)
3904   for (i=0; i<m; i++) {
3905     nnz = Ii[i+1]- Ii[i];
3906     JJ  = J + Ii[i];
3907     if (nnz < 0) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Local row %D has a negative %D number of columns",i,nnz);
3908     if (nnz && (JJ[0] < 0)) SETERRRQ1(PETSC_ERR_ARG_WRONGSTATE,"Row %D starts with negative column index",i,j);
3909     if (nnz && (JJ[nnz-1] >= B->cmap->N) SETERRRQ3(PETSC_ERR_ARG_WRONGSTATE,"Row %D ends with too large a column index %D (max allowed %D)",i,JJ[nnz-1],B->cmap->N);
3910   }
3911 #endif
3912 
3913   for (i=0; i<m; i++) {
3914     nnz     = Ii[i+1]- Ii[i];
3915     JJ      = J + Ii[i];
3916     nnz_max = PetscMax(nnz_max,nnz);
3917     d       = 0;
3918     for (j=0; j<nnz; j++) {
3919       if (cstart <= JJ[j] && JJ[j] < cend) d++;
3920     }
3921     d_nnz[i] = d;
3922     o_nnz[i] = nnz - d;
3923   }
3924   ierr = MatMPIAIJSetPreallocation(B,0,d_nnz,0,o_nnz);CHKERRQ(ierr);
3925   ierr = PetscFree2(d_nnz,o_nnz);CHKERRQ(ierr);
3926 
3927   if (v) values = (PetscScalar*)v;
3928   else {
3929     ierr = PetscMalloc((nnz_max+1)*sizeof(PetscScalar),&values);CHKERRQ(ierr);
3930     ierr = PetscMemzero(values,nnz_max*sizeof(PetscScalar));CHKERRQ(ierr);
3931   }
3932 
3933   for (i=0; i<m; i++) {
3934     ii   = i + rstart;
3935     nnz  = Ii[i+1]- Ii[i];
3936     ierr = MatSetValues_MPIAIJ(B,1,&ii,nnz,J+Ii[i],values+(v ? Ii[i] : 0),INSERT_VALUES);CHKERRQ(ierr);
3937   }
3938   ierr = MatAssemblyBegin(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
3939   ierr = MatAssemblyEnd(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
3940 
3941   if (!v) {
3942     ierr = PetscFree(values);CHKERRQ(ierr);
3943   }
3944   ierr = MatSetOption(B,MAT_NEW_NONZERO_LOCATION_ERR,PETSC_TRUE);CHKERRQ(ierr);
3945   PetscFunctionReturn(0);
3946 }
3947 
3948 #undef __FUNCT__
3949 #define __FUNCT__ "MatMPIAIJSetPreallocationCSR"
3950 /*@
3951    MatMPIAIJSetPreallocationCSR - Allocates memory for a sparse parallel matrix in AIJ format
3952    (the default parallel PETSc format).
3953 
3954    Collective on MPI_Comm
3955 
3956    Input Parameters:
3957 +  B - the matrix
3958 .  i - the indices into j for the start of each local row (starts with zero)
3959 .  j - the column indices for each local row (starts with zero)
3960 -  v - optional values in the matrix
3961 
3962    Level: developer
3963 
3964    Notes:
3965        The i, j, and a arrays ARE copied by this routine into the internal format used by PETSc;
3966      thus you CANNOT change the matrix entries by changing the values of a[] after you have
3967      called this routine. Use MatCreateMPIAIJWithSplitArrays() to avoid needing to copy the arrays.
3968 
3969        The i and j indices are 0 based, and i indices are indices corresponding to the local j array.
3970 
3971        The format which is used for the sparse matrix input, is equivalent to a
3972     row-major ordering.. i.e for the following matrix, the input data expected is
3973     as shown:
3974 
3975         1 0 0
3976         2 0 3     P0
3977        -------
3978         4 5 6     P1
3979 
3980      Process0 [P0]: rows_owned=[0,1]
3981         i =  {0,1,3}  [size = nrow+1  = 2+1]
3982         j =  {0,0,2}  [size = nz = 6]
3983         v =  {1,2,3}  [size = nz = 6]
3984 
3985      Process1 [P1]: rows_owned=[2]
3986         i =  {0,3}    [size = nrow+1  = 1+1]
3987         j =  {0,1,2}  [size = nz = 6]
3988         v =  {4,5,6}  [size = nz = 6]
3989 
3990 .keywords: matrix, aij, compressed row, sparse, parallel
3991 
3992 .seealso: MatCreate(), MatCreateSeqAIJ(), MatSetValues(), MatMPIAIJSetPreallocation(), MatCreateAIJ(), MPIAIJ,
3993           MatCreateSeqAIJWithArrays(), MatCreateMPIAIJWithSplitArrays()
3994 @*/
3995 PetscErrorCode  MatMPIAIJSetPreallocationCSR(Mat B,const PetscInt i[],const PetscInt j[], const PetscScalar v[])
3996 {
3997   PetscErrorCode ierr;
3998 
3999   PetscFunctionBegin;
4000   ierr = PetscTryMethod(B,"MatMPIAIJSetPreallocationCSR_C",(Mat,const PetscInt[],const PetscInt[],const PetscScalar[]),(B,i,j,v));CHKERRQ(ierr);
4001   PetscFunctionReturn(0);
4002 }
4003 
4004 #undef __FUNCT__
4005 #define __FUNCT__ "MatMPIAIJSetPreallocation"
4006 /*@C
4007    MatMPIAIJSetPreallocation - Preallocates memory for a sparse parallel matrix in AIJ format
4008    (the default parallel PETSc format).  For good matrix assembly performance
4009    the user should preallocate the matrix storage by setting the parameters
4010    d_nz (or d_nnz) and o_nz (or o_nnz).  By setting these parameters accurately,
4011    performance can be increased by more than a factor of 50.
4012 
4013    Collective on MPI_Comm
4014 
4015    Input Parameters:
4016 +  A - the matrix
4017 .  d_nz  - number of nonzeros per row in DIAGONAL portion of local submatrix
4018            (same value is used for all local rows)
4019 .  d_nnz - array containing the number of nonzeros in the various rows of the
4020            DIAGONAL portion of the local submatrix (possibly different for each row)
4021            or NULL, if d_nz is used to specify the nonzero structure.
4022            The size of this array is equal to the number of local rows, i.e 'm'.
4023            For matrices that will be factored, you must leave room for (and set)
4024            the diagonal entry even if it is zero.
4025 .  o_nz  - number of nonzeros per row in the OFF-DIAGONAL portion of local
4026            submatrix (same value is used for all local rows).
4027 -  o_nnz - array containing the number of nonzeros in the various rows of the
4028            OFF-DIAGONAL portion of the local submatrix (possibly different for
4029            each row) or NULL, if o_nz is used to specify the nonzero
4030            structure. The size of this array is equal to the number
4031            of local rows, i.e 'm'.
4032 
4033    If the *_nnz parameter is given then the *_nz parameter is ignored
4034 
4035    The AIJ format (also called the Yale sparse matrix format or
4036    compressed row storage (CSR)), is fully compatible with standard Fortran 77
4037    storage.  The stored row and column indices begin with zero.
4038    See the <A href="../../docs/manual.pdf#nameddest=ch_mat">Mat chapter of the users manual</A> for details.
4039 
4040    The parallel matrix is partitioned such that the first m0 rows belong to
4041    process 0, the next m1 rows belong to process 1, the next m2 rows belong
4042    to process 2 etc.. where m0,m1,m2... are the input parameter 'm'.
4043 
4044    The DIAGONAL portion of the local submatrix of a processor can be defined
4045    as the submatrix which is obtained by extraction the part corresponding to
4046    the rows r1-r2 and columns c1-c2 of the global matrix, where r1 is the
4047    first row that belongs to the processor, r2 is the last row belonging to
4048    the this processor, and c1-c2 is range of indices of the local part of a
4049    vector suitable for applying the matrix to.  This is an mxn matrix.  In the
4050    common case of a square matrix, the row and column ranges are the same and
4051    the DIAGONAL part is also square. The remaining portion of the local
4052    submatrix (mxN) constitute the OFF-DIAGONAL portion.
4053 
4054    If o_nnz, d_nnz are specified, then o_nz, and d_nz are ignored.
4055 
4056    You can call MatGetInfo() to get information on how effective the preallocation was;
4057    for example the fields mallocs,nz_allocated,nz_used,nz_unneeded;
4058    You can also run with the option -info and look for messages with the string
4059    malloc in them to see if additional memory allocation was needed.
4060 
4061    Example usage:
4062 
4063    Consider the following 8x8 matrix with 34 non-zero values, that is
4064    assembled across 3 processors. Lets assume that proc0 owns 3 rows,
4065    proc1 owns 3 rows, proc2 owns 2 rows. This division can be shown
4066    as follows:
4067 
4068 .vb
4069             1  2  0  |  0  3  0  |  0  4
4070     Proc0   0  5  6  |  7  0  0  |  8  0
4071             9  0 10  | 11  0  0  | 12  0
4072     -------------------------------------
4073            13  0 14  | 15 16 17  |  0  0
4074     Proc1   0 18  0  | 19 20 21  |  0  0
4075             0  0  0  | 22 23  0  | 24  0
4076     -------------------------------------
4077     Proc2  25 26 27  |  0  0 28  | 29  0
4078            30  0  0  | 31 32 33  |  0 34
4079 .ve
4080 
4081    This can be represented as a collection of submatrices as:
4082 
4083 .vb
4084       A B C
4085       D E F
4086       G H I
4087 .ve
4088 
4089    Where the submatrices A,B,C are owned by proc0, D,E,F are
4090    owned by proc1, G,H,I are owned by proc2.
4091 
4092    The 'm' parameters for proc0,proc1,proc2 are 3,3,2 respectively.
4093    The 'n' parameters for proc0,proc1,proc2 are 3,3,2 respectively.
4094    The 'M','N' parameters are 8,8, and have the same values on all procs.
4095 
4096    The DIAGONAL submatrices corresponding to proc0,proc1,proc2 are
4097    submatrices [A], [E], [I] respectively. The OFF-DIAGONAL submatrices
4098    corresponding to proc0,proc1,proc2 are [BC], [DF], [GH] respectively.
4099    Internally, each processor stores the DIAGONAL part, and the OFF-DIAGONAL
4100    part as SeqAIJ matrices. for eg: proc1 will store [E] as a SeqAIJ
4101    matrix, ans [DF] as another SeqAIJ matrix.
4102 
4103    When d_nz, o_nz parameters are specified, d_nz storage elements are
4104    allocated for every row of the local diagonal submatrix, and o_nz
4105    storage locations are allocated for every row of the OFF-DIAGONAL submat.
4106    One way to choose d_nz and o_nz is to use the max nonzerors per local
4107    rows for each of the local DIAGONAL, and the OFF-DIAGONAL submatrices.
4108    In this case, the values of d_nz,o_nz are:
4109 .vb
4110      proc0 : dnz = 2, o_nz = 2
4111      proc1 : dnz = 3, o_nz = 2
4112      proc2 : dnz = 1, o_nz = 4
4113 .ve
4114    We are allocating m*(d_nz+o_nz) storage locations for every proc. This
4115    translates to 3*(2+2)=12 for proc0, 3*(3+2)=15 for proc1, 2*(1+4)=10
4116    for proc3. i.e we are using 12+15+10=37 storage locations to store
4117    34 values.
4118 
4119    When d_nnz, o_nnz parameters are specified, the storage is specified
4120    for every row, coresponding to both DIAGONAL and OFF-DIAGONAL submatrices.
4121    In the above case the values for d_nnz,o_nnz are:
4122 .vb
4123      proc0: d_nnz = [2,2,2] and o_nnz = [2,2,2]
4124      proc1: d_nnz = [3,3,2] and o_nnz = [2,1,1]
4125      proc2: d_nnz = [1,1]   and o_nnz = [4,4]
4126 .ve
4127    Here the space allocated is sum of all the above values i.e 34, and
4128    hence pre-allocation is perfect.
4129 
4130    Level: intermediate
4131 
4132 .keywords: matrix, aij, compressed row, sparse, parallel
4133 
4134 .seealso: MatCreate(), MatCreateSeqAIJ(), MatSetValues(), MatCreateAIJ(), MatMPIAIJSetPreallocationCSR(),
4135           MPIAIJ, MatGetInfo(), PetscSplitOwnership()
4136 @*/
4137 PetscErrorCode  MatMPIAIJSetPreallocation(Mat B,PetscInt d_nz,const PetscInt d_nnz[],PetscInt o_nz,const PetscInt o_nnz[])
4138 {
4139   PetscErrorCode ierr;
4140 
4141   PetscFunctionBegin;
4142   PetscValidHeaderSpecific(B,MAT_CLASSID,1);
4143   PetscValidType(B,1);
4144   ierr = PetscTryMethod(B,"MatMPIAIJSetPreallocation_C",(Mat,PetscInt,const PetscInt[],PetscInt,const PetscInt[]),(B,d_nz,d_nnz,o_nz,o_nnz));CHKERRQ(ierr);
4145   PetscFunctionReturn(0);
4146 }
4147 
4148 #undef __FUNCT__
4149 #define __FUNCT__ "MatCreateMPIAIJWithArrays"
4150 /*@
4151      MatCreateMPIAIJWithArrays - creates a MPI AIJ matrix using arrays that contain in standard
4152          CSR format the local rows.
4153 
4154    Collective on MPI_Comm
4155 
4156    Input Parameters:
4157 +  comm - MPI communicator
4158 .  m - number of local rows (Cannot be PETSC_DECIDE)
4159 .  n - This value should be the same as the local size used in creating the
4160        x vector for the matrix-vector product y = Ax. (or PETSC_DECIDE to have
4161        calculated if N is given) For square matrices n is almost always m.
4162 .  M - number of global rows (or PETSC_DETERMINE to have calculated if m is given)
4163 .  N - number of global columns (or PETSC_DETERMINE to have calculated if n is given)
4164 .   i - row indices
4165 .   j - column indices
4166 -   a - matrix values
4167 
4168    Output Parameter:
4169 .   mat - the matrix
4170 
4171    Level: intermediate
4172 
4173    Notes:
4174        The i, j, and a arrays ARE copied by this routine into the internal format used by PETSc;
4175      thus you CANNOT change the matrix entries by changing the values of a[] after you have
4176      called this routine. Use MatCreateMPIAIJWithSplitArrays() to avoid needing to copy the arrays.
4177 
4178        The i and j indices are 0 based, and i indices are indices corresponding to the local j array.
4179 
4180        The format which is used for the sparse matrix input, is equivalent to a
4181     row-major ordering.. i.e for the following matrix, the input data expected is
4182     as shown:
4183 
4184         1 0 0
4185         2 0 3     P0
4186        -------
4187         4 5 6     P1
4188 
4189      Process0 [P0]: rows_owned=[0,1]
4190         i =  {0,1,3}  [size = nrow+1  = 2+1]
4191         j =  {0,0,2}  [size = nz = 6]
4192         v =  {1,2,3}  [size = nz = 6]
4193 
4194      Process1 [P1]: rows_owned=[2]
4195         i =  {0,3}    [size = nrow+1  = 1+1]
4196         j =  {0,1,2}  [size = nz = 6]
4197         v =  {4,5,6}  [size = nz = 6]
4198 
4199 .keywords: matrix, aij, compressed row, sparse, parallel
4200 
4201 .seealso: MatCreate(), MatCreateSeqAIJ(), MatSetValues(), MatMPIAIJSetPreallocation(), MatMPIAIJSetPreallocationCSR(),
4202           MPIAIJ, MatCreateAIJ(), MatCreateMPIAIJWithSplitArrays()
4203 @*/
4204 PetscErrorCode  MatCreateMPIAIJWithArrays(MPI_Comm comm,PetscInt m,PetscInt n,PetscInt M,PetscInt N,const PetscInt i[],const PetscInt j[],const PetscScalar a[],Mat *mat)
4205 {
4206   PetscErrorCode ierr;
4207 
4208   PetscFunctionBegin;
4209   if (i[0]) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"i (row indices) must start with 0");
4210   if (m < 0) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"local number of rows (m) cannot be PETSC_DECIDE, or negative");
4211   ierr = MatCreate(comm,mat);CHKERRQ(ierr);
4212   ierr = MatSetSizes(*mat,m,n,M,N);CHKERRQ(ierr);
4213   /* ierr = MatSetBlockSizes(M,bs,cbs);CHKERRQ(ierr); */
4214   ierr = MatSetType(*mat,MATMPIAIJ);CHKERRQ(ierr);
4215   ierr = MatMPIAIJSetPreallocationCSR(*mat,i,j,a);CHKERRQ(ierr);
4216   PetscFunctionReturn(0);
4217 }
4218 
4219 #undef __FUNCT__
4220 #define __FUNCT__ "MatCreateAIJ"
4221 /*@C
4222    MatCreateAIJ - Creates a sparse parallel matrix in AIJ format
4223    (the default parallel PETSc format).  For good matrix assembly performance
4224    the user should preallocate the matrix storage by setting the parameters
4225    d_nz (or d_nnz) and o_nz (or o_nnz).  By setting these parameters accurately,
4226    performance can be increased by more than a factor of 50.
4227 
4228    Collective on MPI_Comm
4229 
4230    Input Parameters:
4231 +  comm - MPI communicator
4232 .  m - number of local rows (or PETSC_DECIDE to have calculated if M is given)
4233            This value should be the same as the local size used in creating the
4234            y vector for the matrix-vector product y = Ax.
4235 .  n - This value should be the same as the local size used in creating the
4236        x vector for the matrix-vector product y = Ax. (or PETSC_DECIDE to have
4237        calculated if N is given) For square matrices n is almost always m.
4238 .  M - number of global rows (or PETSC_DETERMINE to have calculated if m is given)
4239 .  N - number of global columns (or PETSC_DETERMINE to have calculated if n is given)
4240 .  d_nz  - number of nonzeros per row in DIAGONAL portion of local submatrix
4241            (same value is used for all local rows)
4242 .  d_nnz - array containing the number of nonzeros in the various rows of the
4243            DIAGONAL portion of the local submatrix (possibly different for each row)
4244            or NULL, if d_nz is used to specify the nonzero structure.
4245            The size of this array is equal to the number of local rows, i.e 'm'.
4246 .  o_nz  - number of nonzeros per row in the OFF-DIAGONAL portion of local
4247            submatrix (same value is used for all local rows).
4248 -  o_nnz - array containing the number of nonzeros in the various rows of the
4249            OFF-DIAGONAL portion of the local submatrix (possibly different for
4250            each row) or NULL, if o_nz is used to specify the nonzero
4251            structure. The size of this array is equal to the number
4252            of local rows, i.e 'm'.
4253 
4254    Output Parameter:
4255 .  A - the matrix
4256 
4257    It is recommended that one use the MatCreate(), MatSetType() and/or MatSetFromOptions(),
4258    MatXXXXSetPreallocation() paradgm instead of this routine directly.
4259    [MatXXXXSetPreallocation() is, for example, MatSeqAIJSetPreallocation]
4260 
4261    Notes:
4262    If the *_nnz parameter is given then the *_nz parameter is ignored
4263 
4264    m,n,M,N parameters specify the size of the matrix, and its partitioning across
4265    processors, while d_nz,d_nnz,o_nz,o_nnz parameters specify the approximate
4266    storage requirements for this matrix.
4267 
4268    If PETSC_DECIDE or  PETSC_DETERMINE is used for a particular argument on one
4269    processor than it must be used on all processors that share the object for
4270    that argument.
4271 
4272    The user MUST specify either the local or global matrix dimensions
4273    (possibly both).
4274 
4275    The parallel matrix is partitioned across processors such that the
4276    first m0 rows belong to process 0, the next m1 rows belong to
4277    process 1, the next m2 rows belong to process 2 etc.. where
4278    m0,m1,m2,.. are the input parameter 'm'. i.e each processor stores
4279    values corresponding to [m x N] submatrix.
4280 
4281    The columns are logically partitioned with the n0 columns belonging
4282    to 0th partition, the next n1 columns belonging to the next
4283    partition etc.. where n0,n1,n2... are the the input parameter 'n'.
4284 
4285    The DIAGONAL portion of the local submatrix on any given processor
4286    is the submatrix corresponding to the rows and columns m,n
4287    corresponding to the given processor. i.e diagonal matrix on
4288    process 0 is [m0 x n0], diagonal matrix on process 1 is [m1 x n1]
4289    etc. The remaining portion of the local submatrix [m x (N-n)]
4290    constitute the OFF-DIAGONAL portion. The example below better
4291    illustrates this concept.
4292 
4293    For a square global matrix we define each processor's diagonal portion
4294    to be its local rows and the corresponding columns (a square submatrix);
4295    each processor's off-diagonal portion encompasses the remainder of the
4296    local matrix (a rectangular submatrix).
4297 
4298    If o_nnz, d_nnz are specified, then o_nz, and d_nz are ignored.
4299 
4300    When calling this routine with a single process communicator, a matrix of
4301    type SEQAIJ is returned.  If a matrix of type MPIAIJ is desired for this
4302    type of communicator, use the construction mechanism:
4303      MatCreate(...,&A); MatSetType(A,MATMPIAIJ); MatSetSizes(A, m,n,M,N); MatMPIAIJSetPreallocation(A,...);
4304 
4305    By default, this format uses inodes (identical nodes) when possible.
4306    We search for consecutive rows with the same nonzero structure, thereby
4307    reusing matrix information to achieve increased efficiency.
4308 
4309    Options Database Keys:
4310 +  -mat_no_inode  - Do not use inodes
4311 .  -mat_inode_limit <limit> - Sets inode limit (max limit=5)
4312 -  -mat_aij_oneindex - Internally use indexing starting at 1
4313         rather than 0.  Note that when calling MatSetValues(),
4314         the user still MUST index entries starting at 0!
4315 
4316 
4317    Example usage:
4318 
4319    Consider the following 8x8 matrix with 34 non-zero values, that is
4320    assembled across 3 processors. Lets assume that proc0 owns 3 rows,
4321    proc1 owns 3 rows, proc2 owns 2 rows. This division can be shown
4322    as follows:
4323 
4324 .vb
4325             1  2  0  |  0  3  0  |  0  4
4326     Proc0   0  5  6  |  7  0  0  |  8  0
4327             9  0 10  | 11  0  0  | 12  0
4328     -------------------------------------
4329            13  0 14  | 15 16 17  |  0  0
4330     Proc1   0 18  0  | 19 20 21  |  0  0
4331             0  0  0  | 22 23  0  | 24  0
4332     -------------------------------------
4333     Proc2  25 26 27  |  0  0 28  | 29  0
4334            30  0  0  | 31 32 33  |  0 34
4335 .ve
4336 
4337    This can be represented as a collection of submatrices as:
4338 
4339 .vb
4340       A B C
4341       D E F
4342       G H I
4343 .ve
4344 
4345    Where the submatrices A,B,C are owned by proc0, D,E,F are
4346    owned by proc1, G,H,I are owned by proc2.
4347 
4348    The 'm' parameters for proc0,proc1,proc2 are 3,3,2 respectively.
4349    The 'n' parameters for proc0,proc1,proc2 are 3,3,2 respectively.
4350    The 'M','N' parameters are 8,8, and have the same values on all procs.
4351 
4352    The DIAGONAL submatrices corresponding to proc0,proc1,proc2 are
4353    submatrices [A], [E], [I] respectively. The OFF-DIAGONAL submatrices
4354    corresponding to proc0,proc1,proc2 are [BC], [DF], [GH] respectively.
4355    Internally, each processor stores the DIAGONAL part, and the OFF-DIAGONAL
4356    part as SeqAIJ matrices. for eg: proc1 will store [E] as a SeqAIJ
4357    matrix, ans [DF] as another SeqAIJ matrix.
4358 
4359    When d_nz, o_nz parameters are specified, d_nz storage elements are
4360    allocated for every row of the local diagonal submatrix, and o_nz
4361    storage locations are allocated for every row of the OFF-DIAGONAL submat.
4362    One way to choose d_nz and o_nz is to use the max nonzerors per local
4363    rows for each of the local DIAGONAL, and the OFF-DIAGONAL submatrices.
4364    In this case, the values of d_nz,o_nz are:
4365 .vb
4366      proc0 : dnz = 2, o_nz = 2
4367      proc1 : dnz = 3, o_nz = 2
4368      proc2 : dnz = 1, o_nz = 4
4369 .ve
4370    We are allocating m*(d_nz+o_nz) storage locations for every proc. This
4371    translates to 3*(2+2)=12 for proc0, 3*(3+2)=15 for proc1, 2*(1+4)=10
4372    for proc3. i.e we are using 12+15+10=37 storage locations to store
4373    34 values.
4374 
4375    When d_nnz, o_nnz parameters are specified, the storage is specified
4376    for every row, coresponding to both DIAGONAL and OFF-DIAGONAL submatrices.
4377    In the above case the values for d_nnz,o_nnz are:
4378 .vb
4379      proc0: d_nnz = [2,2,2] and o_nnz = [2,2,2]
4380      proc1: d_nnz = [3,3,2] and o_nnz = [2,1,1]
4381      proc2: d_nnz = [1,1]   and o_nnz = [4,4]
4382 .ve
4383    Here the space allocated is sum of all the above values i.e 34, and
4384    hence pre-allocation is perfect.
4385 
4386    Level: intermediate
4387 
4388 .keywords: matrix, aij, compressed row, sparse, parallel
4389 
4390 .seealso: MatCreate(), MatCreateSeqAIJ(), MatSetValues(), MatMPIAIJSetPreallocation(), MatMPIAIJSetPreallocationCSR(),
4391           MPIAIJ, MatCreateMPIAIJWithArrays()
4392 @*/
4393 PetscErrorCode  MatCreateAIJ(MPI_Comm comm,PetscInt m,PetscInt n,PetscInt M,PetscInt N,PetscInt d_nz,const PetscInt d_nnz[],PetscInt o_nz,const PetscInt o_nnz[],Mat *A)
4394 {
4395   PetscErrorCode ierr;
4396   PetscMPIInt    size;
4397 
4398   PetscFunctionBegin;
4399   ierr = MatCreate(comm,A);CHKERRQ(ierr);
4400   ierr = MatSetSizes(*A,m,n,M,N);CHKERRQ(ierr);
4401   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
4402   if (size > 1) {
4403     ierr = MatSetType(*A,MATMPIAIJ);CHKERRQ(ierr);
4404     ierr = MatMPIAIJSetPreallocation(*A,d_nz,d_nnz,o_nz,o_nnz);CHKERRQ(ierr);
4405   } else {
4406     ierr = MatSetType(*A,MATSEQAIJ);CHKERRQ(ierr);
4407     ierr = MatSeqAIJSetPreallocation(*A,d_nz,d_nnz);CHKERRQ(ierr);
4408   }
4409   PetscFunctionReturn(0);
4410 }
4411 
4412 #undef __FUNCT__
4413 #define __FUNCT__ "MatMPIAIJGetSeqAIJ"
4414 PetscErrorCode  MatMPIAIJGetSeqAIJ(Mat A,Mat *Ad,Mat *Ao,const PetscInt *colmap[])
4415 {
4416   Mat_MPIAIJ *a = (Mat_MPIAIJ*)A->data;
4417 
4418   PetscFunctionBegin;
4419   *Ad     = a->A;
4420   *Ao     = a->B;
4421   *colmap = a->garray;
4422   PetscFunctionReturn(0);
4423 }
4424 
4425 #undef __FUNCT__
4426 #define __FUNCT__ "MatSetColoring_MPIAIJ"
4427 PetscErrorCode MatSetColoring_MPIAIJ(Mat A,ISColoring coloring)
4428 {
4429   PetscErrorCode ierr;
4430   PetscInt       i;
4431   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
4432 
4433   PetscFunctionBegin;
4434   if (coloring->ctype == IS_COLORING_GLOBAL) {
4435     ISColoringValue *allcolors,*colors;
4436     ISColoring      ocoloring;
4437 
4438     /* set coloring for diagonal portion */
4439     ierr = MatSetColoring_SeqAIJ(a->A,coloring);CHKERRQ(ierr);
4440 
4441     /* set coloring for off-diagonal portion */
4442     ierr = ISAllGatherColors(PetscObjectComm((PetscObject)A),coloring->n,coloring->colors,NULL,&allcolors);CHKERRQ(ierr);
4443     ierr = PetscMalloc((a->B->cmap->n+1)*sizeof(ISColoringValue),&colors);CHKERRQ(ierr);
4444     for (i=0; i<a->B->cmap->n; i++) {
4445       colors[i] = allcolors[a->garray[i]];
4446     }
4447     ierr = PetscFree(allcolors);CHKERRQ(ierr);
4448     ierr = ISColoringCreate(MPI_COMM_SELF,coloring->n,a->B->cmap->n,colors,&ocoloring);CHKERRQ(ierr);
4449     ierr = MatSetColoring_SeqAIJ(a->B,ocoloring);CHKERRQ(ierr);
4450     ierr = ISColoringDestroy(&ocoloring);CHKERRQ(ierr);
4451   } else if (coloring->ctype == IS_COLORING_GHOSTED) {
4452     ISColoringValue *colors;
4453     PetscInt        *larray;
4454     ISColoring      ocoloring;
4455 
4456     /* set coloring for diagonal portion */
4457     ierr = PetscMalloc((a->A->cmap->n+1)*sizeof(PetscInt),&larray);CHKERRQ(ierr);
4458     for (i=0; i<a->A->cmap->n; i++) {
4459       larray[i] = i + A->cmap->rstart;
4460     }
4461     ierr = ISGlobalToLocalMappingApply(A->cmap->mapping,IS_GTOLM_MASK,a->A->cmap->n,larray,NULL,larray);CHKERRQ(ierr);
4462     ierr = PetscMalloc((a->A->cmap->n+1)*sizeof(ISColoringValue),&colors);CHKERRQ(ierr);
4463     for (i=0; i<a->A->cmap->n; i++) {
4464       colors[i] = coloring->colors[larray[i]];
4465     }
4466     ierr = PetscFree(larray);CHKERRQ(ierr);
4467     ierr = ISColoringCreate(PETSC_COMM_SELF,coloring->n,a->A->cmap->n,colors,&ocoloring);CHKERRQ(ierr);
4468     ierr = MatSetColoring_SeqAIJ(a->A,ocoloring);CHKERRQ(ierr);
4469     ierr = ISColoringDestroy(&ocoloring);CHKERRQ(ierr);
4470 
4471     /* set coloring for off-diagonal portion */
4472     ierr = PetscMalloc((a->B->cmap->n+1)*sizeof(PetscInt),&larray);CHKERRQ(ierr);
4473     ierr = ISGlobalToLocalMappingApply(A->cmap->mapping,IS_GTOLM_MASK,a->B->cmap->n,a->garray,NULL,larray);CHKERRQ(ierr);
4474     ierr = PetscMalloc((a->B->cmap->n+1)*sizeof(ISColoringValue),&colors);CHKERRQ(ierr);
4475     for (i=0; i<a->B->cmap->n; i++) {
4476       colors[i] = coloring->colors[larray[i]];
4477     }
4478     ierr = PetscFree(larray);CHKERRQ(ierr);
4479     ierr = ISColoringCreate(MPI_COMM_SELF,coloring->n,a->B->cmap->n,colors,&ocoloring);CHKERRQ(ierr);
4480     ierr = MatSetColoring_SeqAIJ(a->B,ocoloring);CHKERRQ(ierr);
4481     ierr = ISColoringDestroy(&ocoloring);CHKERRQ(ierr);
4482   } else SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_SUP,"No support ISColoringType %d",(int)coloring->ctype);
4483   PetscFunctionReturn(0);
4484 }
4485 
4486 #undef __FUNCT__
4487 #define __FUNCT__ "MatSetValuesAdifor_MPIAIJ"
4488 PetscErrorCode MatSetValuesAdifor_MPIAIJ(Mat A,PetscInt nl,void *advalues)
4489 {
4490   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
4491   PetscErrorCode ierr;
4492 
4493   PetscFunctionBegin;
4494   ierr = MatSetValuesAdifor_SeqAIJ(a->A,nl,advalues);CHKERRQ(ierr);
4495   ierr = MatSetValuesAdifor_SeqAIJ(a->B,nl,advalues);CHKERRQ(ierr);
4496   PetscFunctionReturn(0);
4497 }
4498 
4499 #undef __FUNCT__
4500 #define __FUNCT__ "MatCreateMPIAIJConcatenateSeqAIJSymbolic"
4501 PetscErrorCode  MatCreateMPIAIJConcatenateSeqAIJSymbolic(MPI_Comm comm,Mat inmat,PetscInt n,Mat *outmat)
4502 {
4503   PetscErrorCode ierr;
4504   PetscInt       m,N,i,rstart,nnz,*dnz,*onz,sum,bs,cbs;
4505   PetscInt       *indx;
4506 
4507   PetscFunctionBegin;
4508   /* This routine will ONLY return MPIAIJ type matrix */
4509   ierr = MatGetSize(inmat,&m,&N);CHKERRQ(ierr);
4510   ierr = MatGetBlockSizes(inmat,&bs,&cbs);CHKERRQ(ierr);
4511   if (n == PETSC_DECIDE) {
4512     ierr = PetscSplitOwnership(comm,&n,&N);CHKERRQ(ierr);
4513   }
4514   /* Check sum(n) = N */
4515   ierr = MPI_Allreduce(&n,&sum,1,MPIU_INT,MPI_SUM,comm);CHKERRQ(ierr);
4516   if (sum != N) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_INCOMP,"Sum of local columns != global columns %d",N);
4517 
4518   ierr    = MPI_Scan(&m, &rstart,1,MPIU_INT,MPI_SUM,comm);CHKERRQ(ierr);
4519   rstart -= m;
4520 
4521   ierr = MatPreallocateInitialize(comm,m,n,dnz,onz);CHKERRQ(ierr);
4522   for (i=0; i<m; i++) {
4523     ierr = MatGetRow_SeqAIJ(inmat,i,&nnz,&indx,NULL);CHKERRQ(ierr);
4524     ierr = MatPreallocateSet(i+rstart,nnz,indx,dnz,onz);CHKERRQ(ierr);
4525     ierr = MatRestoreRow_SeqAIJ(inmat,i,&nnz,&indx,NULL);CHKERRQ(ierr);
4526   }
4527 
4528   ierr = MatCreate(comm,outmat);CHKERRQ(ierr);
4529   ierr = MatSetSizes(*outmat,m,n,PETSC_DETERMINE,PETSC_DETERMINE);CHKERRQ(ierr);
4530   ierr = MatSetBlockSizes(*outmat,bs,cbs);CHKERRQ(ierr);
4531   ierr = MatSetType(*outmat,MATMPIAIJ);CHKERRQ(ierr);
4532   ierr = MatMPIAIJSetPreallocation(*outmat,0,dnz,0,onz);CHKERRQ(ierr);
4533   ierr = MatPreallocateFinalize(dnz,onz);CHKERRQ(ierr);
4534   PetscFunctionReturn(0);
4535 }
4536 
4537 #undef __FUNCT__
4538 #define __FUNCT__ "MatCreateMPIAIJConcatenateSeqAIJNumeric"
4539 PetscErrorCode  MatCreateMPIAIJConcatenateSeqAIJNumeric(MPI_Comm comm,Mat inmat,PetscInt n,Mat outmat)
4540 {
4541   PetscErrorCode ierr;
4542   PetscInt       m,N,i,rstart,nnz,Ii;
4543   PetscInt       *indx;
4544   PetscScalar    *values;
4545 
4546   PetscFunctionBegin;
4547   ierr = MatGetSize(inmat,&m,&N);CHKERRQ(ierr);
4548   ierr = MatGetOwnershipRange(outmat,&rstart,NULL);CHKERRQ(ierr);
4549   for (i=0; i<m; i++) {
4550     ierr = MatGetRow_SeqAIJ(inmat,i,&nnz,&indx,&values);CHKERRQ(ierr);
4551     Ii   = i + rstart;
4552     ierr = MatSetValues(outmat,1,&Ii,nnz,indx,values,INSERT_VALUES);CHKERRQ(ierr);
4553     ierr = MatRestoreRow_SeqAIJ(inmat,i,&nnz,&indx,&values);CHKERRQ(ierr);
4554   }
4555   ierr = MatAssemblyBegin(outmat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
4556   ierr = MatAssemblyEnd(outmat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
4557   PetscFunctionReturn(0);
4558 }
4559 
4560 #undef __FUNCT__
4561 #define __FUNCT__ "MatCreateMPIAIJConcatenateSeqAIJ"
4562 /*@
4563       MatCreateMPIAIJConcatenateSeqAIJ - Creates a single large PETSc matrix by concatenating sequential
4564                  matrices from each processor
4565 
4566     Collective on MPI_Comm
4567 
4568    Input Parameters:
4569 +    comm - the communicators the parallel matrix will live on
4570 .    inmat - the input sequential matrices
4571 .    n - number of local columns (or PETSC_DECIDE)
4572 -    scall - either MAT_INITIAL_MATRIX or MAT_REUSE_MATRIX
4573 
4574    Output Parameter:
4575 .    outmat - the parallel matrix generated
4576 
4577     Level: advanced
4578 
4579    Notes: The number of columns of the matrix in EACH processor MUST be the same.
4580 
4581 @*/
4582 PetscErrorCode  MatCreateMPIAIJConcatenateSeqAIJ(MPI_Comm comm,Mat inmat,PetscInt n,MatReuse scall,Mat *outmat)
4583 {
4584   PetscErrorCode ierr;
4585   PetscMPIInt    size;
4586 
4587   PetscFunctionBegin;
4588   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
4589   ierr = PetscLogEventBegin(MAT_Merge,inmat,0,0,0);CHKERRQ(ierr);
4590   if (size == 1) {
4591     if (scall == MAT_INITIAL_MATRIX) {
4592       ierr = MatDuplicate(inmat,MAT_COPY_VALUES,outmat);CHKERRQ(ierr);
4593     } else {
4594       ierr = MatCopy(inmat,*outmat,SAME_NONZERO_PATTERN);CHKERRQ(ierr);
4595     }
4596   } else {
4597     if (scall == MAT_INITIAL_MATRIX) {
4598       ierr = MatCreateMPIAIJConcatenateSeqAIJSymbolic(comm,inmat,n,outmat);CHKERRQ(ierr);
4599     }
4600     ierr = MatCreateMPIAIJConcatenateSeqAIJNumeric(comm,inmat,n,*outmat);CHKERRQ(ierr);
4601   }
4602   ierr = PetscLogEventEnd(MAT_Merge,inmat,0,0,0);CHKERRQ(ierr);
4603   PetscFunctionReturn(0);
4604 }
4605 
4606 #undef __FUNCT__
4607 #define __FUNCT__ "MatFileSplit"
4608 PetscErrorCode MatFileSplit(Mat A,char *outfile)
4609 {
4610   PetscErrorCode    ierr;
4611   PetscMPIInt       rank;
4612   PetscInt          m,N,i,rstart,nnz;
4613   size_t            len;
4614   const PetscInt    *indx;
4615   PetscViewer       out;
4616   char              *name;
4617   Mat               B;
4618   const PetscScalar *values;
4619 
4620   PetscFunctionBegin;
4621   ierr = MatGetLocalSize(A,&m,0);CHKERRQ(ierr);
4622   ierr = MatGetSize(A,0,&N);CHKERRQ(ierr);
4623   /* Should this be the type of the diagonal block of A? */
4624   ierr = MatCreate(PETSC_COMM_SELF,&B);CHKERRQ(ierr);
4625   ierr = MatSetSizes(B,m,N,m,N);CHKERRQ(ierr);
4626   ierr = MatSetBlockSizes(B,A->rmap->bs,A->cmap->bs);CHKERRQ(ierr);
4627   ierr = MatSetType(B,MATSEQAIJ);CHKERRQ(ierr);
4628   ierr = MatSeqAIJSetPreallocation(B,0,NULL);CHKERRQ(ierr);
4629   ierr = MatGetOwnershipRange(A,&rstart,0);CHKERRQ(ierr);
4630   for (i=0; i<m; i++) {
4631     ierr = MatGetRow(A,i+rstart,&nnz,&indx,&values);CHKERRQ(ierr);
4632     ierr = MatSetValues(B,1,&i,nnz,indx,values,INSERT_VALUES);CHKERRQ(ierr);
4633     ierr = MatRestoreRow(A,i+rstart,&nnz,&indx,&values);CHKERRQ(ierr);
4634   }
4635   ierr = MatAssemblyBegin(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
4636   ierr = MatAssemblyEnd(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
4637 
4638   ierr = MPI_Comm_rank(PetscObjectComm((PetscObject)A),&rank);CHKERRQ(ierr);
4639   ierr = PetscStrlen(outfile,&len);CHKERRQ(ierr);
4640   ierr = PetscMalloc((len+5)*sizeof(char),&name);CHKERRQ(ierr);
4641   sprintf(name,"%s.%d",outfile,rank);
4642   ierr = PetscViewerBinaryOpen(PETSC_COMM_SELF,name,FILE_MODE_APPEND,&out);CHKERRQ(ierr);
4643   ierr = PetscFree(name);CHKERRQ(ierr);
4644   ierr = MatView(B,out);CHKERRQ(ierr);
4645   ierr = PetscViewerDestroy(&out);CHKERRQ(ierr);
4646   ierr = MatDestroy(&B);CHKERRQ(ierr);
4647   PetscFunctionReturn(0);
4648 }
4649 
4650 extern PetscErrorCode MatDestroy_MPIAIJ(Mat);
4651 #undef __FUNCT__
4652 #define __FUNCT__ "MatDestroy_MPIAIJ_SeqsToMPI"
4653 PetscErrorCode  MatDestroy_MPIAIJ_SeqsToMPI(Mat A)
4654 {
4655   PetscErrorCode      ierr;
4656   Mat_Merge_SeqsToMPI *merge;
4657   PetscContainer      container;
4658 
4659   PetscFunctionBegin;
4660   ierr = PetscObjectQuery((PetscObject)A,"MatMergeSeqsToMPI",(PetscObject*)&container);CHKERRQ(ierr);
4661   if (container) {
4662     ierr = PetscContainerGetPointer(container,(void**)&merge);CHKERRQ(ierr);
4663     ierr = PetscFree(merge->id_r);CHKERRQ(ierr);
4664     ierr = PetscFree(merge->len_s);CHKERRQ(ierr);
4665     ierr = PetscFree(merge->len_r);CHKERRQ(ierr);
4666     ierr = PetscFree(merge->bi);CHKERRQ(ierr);
4667     ierr = PetscFree(merge->bj);CHKERRQ(ierr);
4668     ierr = PetscFree(merge->buf_ri[0]);CHKERRQ(ierr);
4669     ierr = PetscFree(merge->buf_ri);CHKERRQ(ierr);
4670     ierr = PetscFree(merge->buf_rj[0]);CHKERRQ(ierr);
4671     ierr = PetscFree(merge->buf_rj);CHKERRQ(ierr);
4672     ierr = PetscFree(merge->coi);CHKERRQ(ierr);
4673     ierr = PetscFree(merge->coj);CHKERRQ(ierr);
4674     ierr = PetscFree(merge->owners_co);CHKERRQ(ierr);
4675     ierr = PetscLayoutDestroy(&merge->rowmap);CHKERRQ(ierr);
4676     ierr = PetscFree(merge);CHKERRQ(ierr);
4677     ierr = PetscObjectCompose((PetscObject)A,"MatMergeSeqsToMPI",0);CHKERRQ(ierr);
4678   }
4679   ierr = MatDestroy_MPIAIJ(A);CHKERRQ(ierr);
4680   PetscFunctionReturn(0);
4681 }
4682 
4683 #include <../src/mat/utils/freespace.h>
4684 #include <petscbt.h>
4685 
4686 #undef __FUNCT__
4687 #define __FUNCT__ "MatCreateMPIAIJSumSeqAIJNumeric"
4688 PetscErrorCode  MatCreateMPIAIJSumSeqAIJNumeric(Mat seqmat,Mat mpimat)
4689 {
4690   PetscErrorCode      ierr;
4691   MPI_Comm            comm;
4692   Mat_SeqAIJ          *a  =(Mat_SeqAIJ*)seqmat->data;
4693   PetscMPIInt         size,rank,taga,*len_s;
4694   PetscInt            N=mpimat->cmap->N,i,j,*owners,*ai=a->i,*aj;
4695   PetscInt            proc,m;
4696   PetscInt            **buf_ri,**buf_rj;
4697   PetscInt            k,anzi,*bj_i,*bi,*bj,arow,bnzi,nextaj;
4698   PetscInt            nrows,**buf_ri_k,**nextrow,**nextai;
4699   MPI_Request         *s_waits,*r_waits;
4700   MPI_Status          *status;
4701   MatScalar           *aa=a->a;
4702   MatScalar           **abuf_r,*ba_i;
4703   Mat_Merge_SeqsToMPI *merge;
4704   PetscContainer      container;
4705 
4706   PetscFunctionBegin;
4707   ierr = PetscObjectGetComm((PetscObject)mpimat,&comm);CHKERRQ(ierr);
4708   ierr = PetscLogEventBegin(MAT_Seqstompinum,seqmat,0,0,0);CHKERRQ(ierr);
4709 
4710   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
4711   ierr = MPI_Comm_rank(comm,&rank);CHKERRQ(ierr);
4712 
4713   ierr = PetscObjectQuery((PetscObject)mpimat,"MatMergeSeqsToMPI",(PetscObject*)&container);CHKERRQ(ierr);
4714   ierr = PetscContainerGetPointer(container,(void**)&merge);CHKERRQ(ierr);
4715 
4716   bi     = merge->bi;
4717   bj     = merge->bj;
4718   buf_ri = merge->buf_ri;
4719   buf_rj = merge->buf_rj;
4720 
4721   ierr   = PetscMalloc(size*sizeof(MPI_Status),&status);CHKERRQ(ierr);
4722   owners = merge->rowmap->range;
4723   len_s  = merge->len_s;
4724 
4725   /* send and recv matrix values */
4726   /*-----------------------------*/
4727   ierr = PetscObjectGetNewTag((PetscObject)mpimat,&taga);CHKERRQ(ierr);
4728   ierr = PetscPostIrecvScalar(comm,taga,merge->nrecv,merge->id_r,merge->len_r,&abuf_r,&r_waits);CHKERRQ(ierr);
4729 
4730   ierr = PetscMalloc((merge->nsend+1)*sizeof(MPI_Request),&s_waits);CHKERRQ(ierr);
4731   for (proc=0,k=0; proc<size; proc++) {
4732     if (!len_s[proc]) continue;
4733     i    = owners[proc];
4734     ierr = MPI_Isend(aa+ai[i],len_s[proc],MPIU_MATSCALAR,proc,taga,comm,s_waits+k);CHKERRQ(ierr);
4735     k++;
4736   }
4737 
4738   if (merge->nrecv) {ierr = MPI_Waitall(merge->nrecv,r_waits,status);CHKERRQ(ierr);}
4739   if (merge->nsend) {ierr = MPI_Waitall(merge->nsend,s_waits,status);CHKERRQ(ierr);}
4740   ierr = PetscFree(status);CHKERRQ(ierr);
4741 
4742   ierr = PetscFree(s_waits);CHKERRQ(ierr);
4743   ierr = PetscFree(r_waits);CHKERRQ(ierr);
4744 
4745   /* insert mat values of mpimat */
4746   /*----------------------------*/
4747   ierr = PetscMalloc(N*sizeof(PetscScalar),&ba_i);CHKERRQ(ierr);
4748   ierr = PetscMalloc3(merge->nrecv,PetscInt*,&buf_ri_k,merge->nrecv,PetscInt*,&nextrow,merge->nrecv,PetscInt*,&nextai);CHKERRQ(ierr);
4749 
4750   for (k=0; k<merge->nrecv; k++) {
4751     buf_ri_k[k] = buf_ri[k]; /* beginning of k-th recved i-structure */
4752     nrows       = *(buf_ri_k[k]);
4753     nextrow[k]  = buf_ri_k[k]+1;  /* next row number of k-th recved i-structure */
4754     nextai[k]   = buf_ri_k[k] + (nrows + 1); /* poins to the next i-structure of k-th recved i-structure  */
4755   }
4756 
4757   /* set values of ba */
4758   m = merge->rowmap->n;
4759   for (i=0; i<m; i++) {
4760     arow = owners[rank] + i;
4761     bj_i = bj+bi[i];  /* col indices of the i-th row of mpimat */
4762     bnzi = bi[i+1] - bi[i];
4763     ierr = PetscMemzero(ba_i,bnzi*sizeof(PetscScalar));CHKERRQ(ierr);
4764 
4765     /* add local non-zero vals of this proc's seqmat into ba */
4766     anzi   = ai[arow+1] - ai[arow];
4767     aj     = a->j + ai[arow];
4768     aa     = a->a + ai[arow];
4769     nextaj = 0;
4770     for (j=0; nextaj<anzi; j++) {
4771       if (*(bj_i + j) == aj[nextaj]) { /* bcol == acol */
4772         ba_i[j] += aa[nextaj++];
4773       }
4774     }
4775 
4776     /* add received vals into ba */
4777     for (k=0; k<merge->nrecv; k++) { /* k-th received message */
4778       /* i-th row */
4779       if (i == *nextrow[k]) {
4780         anzi   = *(nextai[k]+1) - *nextai[k];
4781         aj     = buf_rj[k] + *(nextai[k]);
4782         aa     = abuf_r[k] + *(nextai[k]);
4783         nextaj = 0;
4784         for (j=0; nextaj<anzi; j++) {
4785           if (*(bj_i + j) == aj[nextaj]) { /* bcol == acol */
4786             ba_i[j] += aa[nextaj++];
4787           }
4788         }
4789         nextrow[k]++; nextai[k]++;
4790       }
4791     }
4792     ierr = MatSetValues(mpimat,1,&arow,bnzi,bj_i,ba_i,INSERT_VALUES);CHKERRQ(ierr);
4793   }
4794   ierr = MatAssemblyBegin(mpimat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
4795   ierr = MatAssemblyEnd(mpimat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
4796 
4797   ierr = PetscFree(abuf_r[0]);CHKERRQ(ierr);
4798   ierr = PetscFree(abuf_r);CHKERRQ(ierr);
4799   ierr = PetscFree(ba_i);CHKERRQ(ierr);
4800   ierr = PetscFree3(buf_ri_k,nextrow,nextai);CHKERRQ(ierr);
4801   ierr = PetscLogEventEnd(MAT_Seqstompinum,seqmat,0,0,0);CHKERRQ(ierr);
4802   PetscFunctionReturn(0);
4803 }
4804 
4805 extern PetscErrorCode  MatDestroy_MPIAIJ_SeqsToMPI(Mat);
4806 
4807 #undef __FUNCT__
4808 #define __FUNCT__ "MatCreateMPIAIJSumSeqAIJSymbolic"
4809 PetscErrorCode  MatCreateMPIAIJSumSeqAIJSymbolic(MPI_Comm comm,Mat seqmat,PetscInt m,PetscInt n,Mat *mpimat)
4810 {
4811   PetscErrorCode      ierr;
4812   Mat                 B_mpi;
4813   Mat_SeqAIJ          *a=(Mat_SeqAIJ*)seqmat->data;
4814   PetscMPIInt         size,rank,tagi,tagj,*len_s,*len_si,*len_ri;
4815   PetscInt            **buf_rj,**buf_ri,**buf_ri_k;
4816   PetscInt            M=seqmat->rmap->n,N=seqmat->cmap->n,i,*owners,*ai=a->i,*aj=a->j;
4817   PetscInt            len,proc,*dnz,*onz,bs,cbs;
4818   PetscInt            k,anzi,*bi,*bj,*lnk,nlnk,arow,bnzi,nspacedouble=0;
4819   PetscInt            nrows,*buf_s,*buf_si,*buf_si_i,**nextrow,**nextai;
4820   MPI_Request         *si_waits,*sj_waits,*ri_waits,*rj_waits;
4821   MPI_Status          *status;
4822   PetscFreeSpaceList  free_space=NULL,current_space=NULL;
4823   PetscBT             lnkbt;
4824   Mat_Merge_SeqsToMPI *merge;
4825   PetscContainer      container;
4826 
4827   PetscFunctionBegin;
4828   ierr = PetscLogEventBegin(MAT_Seqstompisym,seqmat,0,0,0);CHKERRQ(ierr);
4829 
4830   /* make sure it is a PETSc comm */
4831   ierr = PetscCommDuplicate(comm,&comm,NULL);CHKERRQ(ierr);
4832   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
4833   ierr = MPI_Comm_rank(comm,&rank);CHKERRQ(ierr);
4834 
4835   ierr = PetscNew(Mat_Merge_SeqsToMPI,&merge);CHKERRQ(ierr);
4836   ierr = PetscMalloc(size*sizeof(MPI_Status),&status);CHKERRQ(ierr);
4837 
4838   /* determine row ownership */
4839   /*---------------------------------------------------------*/
4840   ierr = PetscLayoutCreate(comm,&merge->rowmap);CHKERRQ(ierr);
4841   ierr = PetscLayoutSetLocalSize(merge->rowmap,m);CHKERRQ(ierr);
4842   ierr = PetscLayoutSetSize(merge->rowmap,M);CHKERRQ(ierr);
4843   ierr = PetscLayoutSetBlockSize(merge->rowmap,1);CHKERRQ(ierr);
4844   ierr = PetscLayoutSetUp(merge->rowmap);CHKERRQ(ierr);
4845   ierr = PetscMalloc(size*sizeof(PetscMPIInt),&len_si);CHKERRQ(ierr);
4846   ierr = PetscMalloc(size*sizeof(PetscMPIInt),&merge->len_s);CHKERRQ(ierr);
4847 
4848   m      = merge->rowmap->n;
4849   owners = merge->rowmap->range;
4850 
4851   /* determine the number of messages to send, their lengths */
4852   /*---------------------------------------------------------*/
4853   len_s = merge->len_s;
4854 
4855   len          = 0; /* length of buf_si[] */
4856   merge->nsend = 0;
4857   for (proc=0; proc<size; proc++) {
4858     len_si[proc] = 0;
4859     if (proc == rank) {
4860       len_s[proc] = 0;
4861     } else {
4862       len_si[proc] = owners[proc+1] - owners[proc] + 1;
4863       len_s[proc]  = ai[owners[proc+1]] - ai[owners[proc]]; /* num of rows to be sent to [proc] */
4864     }
4865     if (len_s[proc]) {
4866       merge->nsend++;
4867       nrows = 0;
4868       for (i=owners[proc]; i<owners[proc+1]; i++) {
4869         if (ai[i+1] > ai[i]) nrows++;
4870       }
4871       len_si[proc] = 2*(nrows+1);
4872       len         += len_si[proc];
4873     }
4874   }
4875 
4876   /* determine the number and length of messages to receive for ij-structure */
4877   /*-------------------------------------------------------------------------*/
4878   ierr = PetscGatherNumberOfMessages(comm,NULL,len_s,&merge->nrecv);CHKERRQ(ierr);
4879   ierr = PetscGatherMessageLengths2(comm,merge->nsend,merge->nrecv,len_s,len_si,&merge->id_r,&merge->len_r,&len_ri);CHKERRQ(ierr);
4880 
4881   /* post the Irecv of j-structure */
4882   /*-------------------------------*/
4883   ierr = PetscCommGetNewTag(comm,&tagj);CHKERRQ(ierr);
4884   ierr = PetscPostIrecvInt(comm,tagj,merge->nrecv,merge->id_r,merge->len_r,&buf_rj,&rj_waits);CHKERRQ(ierr);
4885 
4886   /* post the Isend of j-structure */
4887   /*--------------------------------*/
4888   ierr = PetscMalloc2(merge->nsend,MPI_Request,&si_waits,merge->nsend,MPI_Request,&sj_waits);CHKERRQ(ierr);
4889 
4890   for (proc=0, k=0; proc<size; proc++) {
4891     if (!len_s[proc]) continue;
4892     i    = owners[proc];
4893     ierr = MPI_Isend(aj+ai[i],len_s[proc],MPIU_INT,proc,tagj,comm,sj_waits+k);CHKERRQ(ierr);
4894     k++;
4895   }
4896 
4897   /* receives and sends of j-structure are complete */
4898   /*------------------------------------------------*/
4899   if (merge->nrecv) {ierr = MPI_Waitall(merge->nrecv,rj_waits,status);CHKERRQ(ierr);}
4900   if (merge->nsend) {ierr = MPI_Waitall(merge->nsend,sj_waits,status);CHKERRQ(ierr);}
4901 
4902   /* send and recv i-structure */
4903   /*---------------------------*/
4904   ierr = PetscCommGetNewTag(comm,&tagi);CHKERRQ(ierr);
4905   ierr = PetscPostIrecvInt(comm,tagi,merge->nrecv,merge->id_r,len_ri,&buf_ri,&ri_waits);CHKERRQ(ierr);
4906 
4907   ierr   = PetscMalloc((len+1)*sizeof(PetscInt),&buf_s);CHKERRQ(ierr);
4908   buf_si = buf_s;  /* points to the beginning of k-th msg to be sent */
4909   for (proc=0,k=0; proc<size; proc++) {
4910     if (!len_s[proc]) continue;
4911     /* form outgoing message for i-structure:
4912          buf_si[0]:                 nrows to be sent
4913                [1:nrows]:           row index (global)
4914                [nrows+1:2*nrows+1]: i-structure index
4915     */
4916     /*-------------------------------------------*/
4917     nrows       = len_si[proc]/2 - 1;
4918     buf_si_i    = buf_si + nrows+1;
4919     buf_si[0]   = nrows;
4920     buf_si_i[0] = 0;
4921     nrows       = 0;
4922     for (i=owners[proc]; i<owners[proc+1]; i++) {
4923       anzi = ai[i+1] - ai[i];
4924       if (anzi) {
4925         buf_si_i[nrows+1] = buf_si_i[nrows] + anzi; /* i-structure */
4926         buf_si[nrows+1]   = i-owners[proc]; /* local row index */
4927         nrows++;
4928       }
4929     }
4930     ierr = MPI_Isend(buf_si,len_si[proc],MPIU_INT,proc,tagi,comm,si_waits+k);CHKERRQ(ierr);
4931     k++;
4932     buf_si += len_si[proc];
4933   }
4934 
4935   if (merge->nrecv) {ierr = MPI_Waitall(merge->nrecv,ri_waits,status);CHKERRQ(ierr);}
4936   if (merge->nsend) {ierr = MPI_Waitall(merge->nsend,si_waits,status);CHKERRQ(ierr);}
4937 
4938   ierr = PetscInfo2(seqmat,"nsend: %D, nrecv: %D\n",merge->nsend,merge->nrecv);CHKERRQ(ierr);
4939   for (i=0; i<merge->nrecv; i++) {
4940     ierr = PetscInfo3(seqmat,"recv len_ri=%D, len_rj=%D from [%D]\n",len_ri[i],merge->len_r[i],merge->id_r[i]);CHKERRQ(ierr);
4941   }
4942 
4943   ierr = PetscFree(len_si);CHKERRQ(ierr);
4944   ierr = PetscFree(len_ri);CHKERRQ(ierr);
4945   ierr = PetscFree(rj_waits);CHKERRQ(ierr);
4946   ierr = PetscFree2(si_waits,sj_waits);CHKERRQ(ierr);
4947   ierr = PetscFree(ri_waits);CHKERRQ(ierr);
4948   ierr = PetscFree(buf_s);CHKERRQ(ierr);
4949   ierr = PetscFree(status);CHKERRQ(ierr);
4950 
4951   /* compute a local seq matrix in each processor */
4952   /*----------------------------------------------*/
4953   /* allocate bi array and free space for accumulating nonzero column info */
4954   ierr  = PetscMalloc((m+1)*sizeof(PetscInt),&bi);CHKERRQ(ierr);
4955   bi[0] = 0;
4956 
4957   /* create and initialize a linked list */
4958   nlnk = N+1;
4959   ierr = PetscLLCreate(N,N,nlnk,lnk,lnkbt);CHKERRQ(ierr);
4960 
4961   /* initial FreeSpace size is 2*(num of local nnz(seqmat)) */
4962   len  = ai[owners[rank+1]] - ai[owners[rank]];
4963   ierr = PetscFreeSpaceGet((PetscInt)(2*len+1),&free_space);CHKERRQ(ierr);
4964 
4965   current_space = free_space;
4966 
4967   /* determine symbolic info for each local row */
4968   ierr = PetscMalloc3(merge->nrecv,PetscInt*,&buf_ri_k,merge->nrecv,PetscInt*,&nextrow,merge->nrecv,PetscInt*,&nextai);CHKERRQ(ierr);
4969 
4970   for (k=0; k<merge->nrecv; k++) {
4971     buf_ri_k[k] = buf_ri[k]; /* beginning of k-th recved i-structure */
4972     nrows       = *buf_ri_k[k];
4973     nextrow[k]  = buf_ri_k[k] + 1;  /* next row number of k-th recved i-structure */
4974     nextai[k]   = buf_ri_k[k] + (nrows + 1); /* poins to the next i-structure of k-th recved i-structure  */
4975   }
4976 
4977   ierr = MatPreallocateInitialize(comm,m,n,dnz,onz);CHKERRQ(ierr);
4978   len  = 0;
4979   for (i=0; i<m; i++) {
4980     bnzi = 0;
4981     /* add local non-zero cols of this proc's seqmat into lnk */
4982     arow  = owners[rank] + i;
4983     anzi  = ai[arow+1] - ai[arow];
4984     aj    = a->j + ai[arow];
4985     ierr  = PetscLLAddSorted(anzi,aj,N,nlnk,lnk,lnkbt);CHKERRQ(ierr);
4986     bnzi += nlnk;
4987     /* add received col data into lnk */
4988     for (k=0; k<merge->nrecv; k++) { /* k-th received message */
4989       if (i == *nextrow[k]) { /* i-th row */
4990         anzi  = *(nextai[k]+1) - *nextai[k];
4991         aj    = buf_rj[k] + *nextai[k];
4992         ierr  = PetscLLAddSorted(anzi,aj,N,nlnk,lnk,lnkbt);CHKERRQ(ierr);
4993         bnzi += nlnk;
4994         nextrow[k]++; nextai[k]++;
4995       }
4996     }
4997     if (len < bnzi) len = bnzi;  /* =max(bnzi) */
4998 
4999     /* if free space is not available, make more free space */
5000     if (current_space->local_remaining<bnzi) {
5001       ierr = PetscFreeSpaceGet(bnzi+current_space->total_array_size,&current_space);CHKERRQ(ierr);
5002       nspacedouble++;
5003     }
5004     /* copy data into free space, then initialize lnk */
5005     ierr = PetscLLClean(N,N,bnzi,lnk,current_space->array,lnkbt);CHKERRQ(ierr);
5006     ierr = MatPreallocateSet(i+owners[rank],bnzi,current_space->array,dnz,onz);CHKERRQ(ierr);
5007 
5008     current_space->array           += bnzi;
5009     current_space->local_used      += bnzi;
5010     current_space->local_remaining -= bnzi;
5011 
5012     bi[i+1] = bi[i] + bnzi;
5013   }
5014 
5015   ierr = PetscFree3(buf_ri_k,nextrow,nextai);CHKERRQ(ierr);
5016 
5017   ierr = PetscMalloc((bi[m]+1)*sizeof(PetscInt),&bj);CHKERRQ(ierr);
5018   ierr = PetscFreeSpaceContiguous(&free_space,bj);CHKERRQ(ierr);
5019   ierr = PetscLLDestroy(lnk,lnkbt);CHKERRQ(ierr);
5020 
5021   /* create symbolic parallel matrix B_mpi */
5022   /*---------------------------------------*/
5023   ierr = MatGetBlockSizes(seqmat,&bs,&cbs);CHKERRQ(ierr);
5024   ierr = MatCreate(comm,&B_mpi);CHKERRQ(ierr);
5025   if (n==PETSC_DECIDE) {
5026     ierr = MatSetSizes(B_mpi,m,n,PETSC_DETERMINE,N);CHKERRQ(ierr);
5027   } else {
5028     ierr = MatSetSizes(B_mpi,m,n,PETSC_DETERMINE,PETSC_DETERMINE);CHKERRQ(ierr);
5029   }
5030   ierr = MatSetBlockSizes(B_mpi,bs,cbs);CHKERRQ(ierr);
5031   ierr = MatSetType(B_mpi,MATMPIAIJ);CHKERRQ(ierr);
5032   ierr = MatMPIAIJSetPreallocation(B_mpi,0,dnz,0,onz);CHKERRQ(ierr);
5033   ierr = MatPreallocateFinalize(dnz,onz);CHKERRQ(ierr);
5034   ierr = MatSetOption(B_mpi,MAT_NEW_NONZERO_ALLOCATION_ERR,PETSC_FALSE);CHKERRQ(ierr);
5035 
5036   /* B_mpi is not ready for use - assembly will be done by MatCreateMPIAIJSumSeqAIJNumeric() */
5037   B_mpi->assembled    = PETSC_FALSE;
5038   B_mpi->ops->destroy = MatDestroy_MPIAIJ_SeqsToMPI;
5039   merge->bi           = bi;
5040   merge->bj           = bj;
5041   merge->buf_ri       = buf_ri;
5042   merge->buf_rj       = buf_rj;
5043   merge->coi          = NULL;
5044   merge->coj          = NULL;
5045   merge->owners_co    = NULL;
5046 
5047   ierr = PetscCommDestroy(&comm);CHKERRQ(ierr);
5048 
5049   /* attach the supporting struct to B_mpi for reuse */
5050   ierr    = PetscContainerCreate(PETSC_COMM_SELF,&container);CHKERRQ(ierr);
5051   ierr    = PetscContainerSetPointer(container,merge);CHKERRQ(ierr);
5052   ierr    = PetscObjectCompose((PetscObject)B_mpi,"MatMergeSeqsToMPI",(PetscObject)container);CHKERRQ(ierr);
5053   ierr    = PetscContainerDestroy(&container);CHKERRQ(ierr);
5054   *mpimat = B_mpi;
5055 
5056   ierr = PetscLogEventEnd(MAT_Seqstompisym,seqmat,0,0,0);CHKERRQ(ierr);
5057   PetscFunctionReturn(0);
5058 }
5059 
5060 #undef __FUNCT__
5061 #define __FUNCT__ "MatCreateMPIAIJSumSeqAIJ"
5062 /*@C
5063       MatCreateMPIAIJSumSeqAIJ - Creates a MPIAIJ matrix by adding sequential
5064                  matrices from each processor
5065 
5066     Collective on MPI_Comm
5067 
5068    Input Parameters:
5069 +    comm - the communicators the parallel matrix will live on
5070 .    seqmat - the input sequential matrices
5071 .    m - number of local rows (or PETSC_DECIDE)
5072 .    n - number of local columns (or PETSC_DECIDE)
5073 -    scall - either MAT_INITIAL_MATRIX or MAT_REUSE_MATRIX
5074 
5075    Output Parameter:
5076 .    mpimat - the parallel matrix generated
5077 
5078     Level: advanced
5079 
5080    Notes:
5081      The dimensions of the sequential matrix in each processor MUST be the same.
5082      The input seqmat is included into the container "Mat_Merge_SeqsToMPI", and will be
5083      destroyed when mpimat is destroyed. Call PetscObjectQuery() to access seqmat.
5084 @*/
5085 PetscErrorCode  MatCreateMPIAIJSumSeqAIJ(MPI_Comm comm,Mat seqmat,PetscInt m,PetscInt n,MatReuse scall,Mat *mpimat)
5086 {
5087   PetscErrorCode ierr;
5088   PetscMPIInt    size;
5089 
5090   PetscFunctionBegin;
5091   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
5092   if (size == 1) {
5093     ierr = PetscLogEventBegin(MAT_Seqstompi,seqmat,0,0,0);CHKERRQ(ierr);
5094     if (scall == MAT_INITIAL_MATRIX) {
5095       ierr = MatDuplicate(seqmat,MAT_COPY_VALUES,mpimat);CHKERRQ(ierr);
5096     } else {
5097       ierr = MatCopy(seqmat,*mpimat,SAME_NONZERO_PATTERN);CHKERRQ(ierr);
5098     }
5099     ierr = PetscLogEventEnd(MAT_Seqstompi,seqmat,0,0,0);CHKERRQ(ierr);
5100     PetscFunctionReturn(0);
5101   }
5102   ierr = PetscLogEventBegin(MAT_Seqstompi,seqmat,0,0,0);CHKERRQ(ierr);
5103   if (scall == MAT_INITIAL_MATRIX) {
5104     ierr = MatCreateMPIAIJSumSeqAIJSymbolic(comm,seqmat,m,n,mpimat);CHKERRQ(ierr);
5105   }
5106   ierr = MatCreateMPIAIJSumSeqAIJNumeric(seqmat,*mpimat);CHKERRQ(ierr);
5107   ierr = PetscLogEventEnd(MAT_Seqstompi,seqmat,0,0,0);CHKERRQ(ierr);
5108   PetscFunctionReturn(0);
5109 }
5110 
5111 #undef __FUNCT__
5112 #define __FUNCT__ "MatMPIAIJGetLocalMat"
5113 /*@
5114      MatMPIAIJGetLocalMat - Creates a SeqAIJ from a MPIAIJ matrix by taking all its local rows and putting them into a sequential vector with
5115           mlocal rows and n columns. Where mlocal is the row count obtained with MatGetLocalSize() and n is the global column count obtained
5116           with MatGetSize()
5117 
5118     Not Collective
5119 
5120    Input Parameters:
5121 +    A - the matrix
5122 .    scall - either MAT_INITIAL_MATRIX or MAT_REUSE_MATRIX
5123 
5124    Output Parameter:
5125 .    A_loc - the local sequential matrix generated
5126 
5127     Level: developer
5128 
5129 .seealso: MatGetOwnerShipRange(), MatMPIAIJGetLocalMatCondensed()
5130 
5131 @*/
5132 PetscErrorCode  MatMPIAIJGetLocalMat(Mat A,MatReuse scall,Mat *A_loc)
5133 {
5134   PetscErrorCode ierr;
5135   Mat_MPIAIJ     *mpimat=(Mat_MPIAIJ*)A->data;
5136   Mat_SeqAIJ     *mat,*a=(Mat_SeqAIJ*)(mpimat->A)->data,*b=(Mat_SeqAIJ*)(mpimat->B)->data;
5137   PetscInt       *ai=a->i,*aj=a->j,*bi=b->i,*bj=b->j,*cmap=mpimat->garray;
5138   MatScalar      *aa=a->a,*ba=b->a,*cam;
5139   PetscScalar    *ca;
5140   PetscInt       am=A->rmap->n,i,j,k,cstart=A->cmap->rstart;
5141   PetscInt       *ci,*cj,col,ncols_d,ncols_o,jo;
5142   PetscBool      match;
5143 
5144   PetscFunctionBegin;
5145   ierr = PetscObjectTypeCompare((PetscObject)A,MATMPIAIJ,&match);CHKERRQ(ierr);
5146   if (!match) SETERRQ(PetscObjectComm((PetscObject)A), PETSC_ERR_SUP,"Requires MPIAIJ matrix as input");
5147   ierr = PetscLogEventBegin(MAT_Getlocalmat,A,0,0,0);CHKERRQ(ierr);
5148   if (scall == MAT_INITIAL_MATRIX) {
5149     ierr  = PetscMalloc((1+am)*sizeof(PetscInt),&ci);CHKERRQ(ierr);
5150     ci[0] = 0;
5151     for (i=0; i<am; i++) {
5152       ci[i+1] = ci[i] + (ai[i+1] - ai[i]) + (bi[i+1] - bi[i]);
5153     }
5154     ierr = PetscMalloc((1+ci[am])*sizeof(PetscInt),&cj);CHKERRQ(ierr);
5155     ierr = PetscMalloc((1+ci[am])*sizeof(PetscScalar),&ca);CHKERRQ(ierr);
5156     k    = 0;
5157     for (i=0; i<am; i++) {
5158       ncols_o = bi[i+1] - bi[i];
5159       ncols_d = ai[i+1] - ai[i];
5160       /* off-diagonal portion of A */
5161       for (jo=0; jo<ncols_o; jo++) {
5162         col = cmap[*bj];
5163         if (col >= cstart) break;
5164         cj[k]   = col; bj++;
5165         ca[k++] = *ba++;
5166       }
5167       /* diagonal portion of A */
5168       for (j=0; j<ncols_d; j++) {
5169         cj[k]   = cstart + *aj++;
5170         ca[k++] = *aa++;
5171       }
5172       /* off-diagonal portion of A */
5173       for (j=jo; j<ncols_o; j++) {
5174         cj[k]   = cmap[*bj++];
5175         ca[k++] = *ba++;
5176       }
5177     }
5178     /* put together the new matrix */
5179     ierr = MatCreateSeqAIJWithArrays(PETSC_COMM_SELF,am,A->cmap->N,ci,cj,ca,A_loc);CHKERRQ(ierr);
5180     /* MatCreateSeqAIJWithArrays flags matrix so PETSc doesn't free the user's arrays. */
5181     /* Since these are PETSc arrays, change flags to free them as necessary. */
5182     mat          = (Mat_SeqAIJ*)(*A_loc)->data;
5183     mat->free_a  = PETSC_TRUE;
5184     mat->free_ij = PETSC_TRUE;
5185     mat->nonew   = 0;
5186   } else if (scall == MAT_REUSE_MATRIX) {
5187     mat=(Mat_SeqAIJ*)(*A_loc)->data;
5188     ci = mat->i; cj = mat->j; cam = mat->a;
5189     for (i=0; i<am; i++) {
5190       /* off-diagonal portion of A */
5191       ncols_o = bi[i+1] - bi[i];
5192       for (jo=0; jo<ncols_o; jo++) {
5193         col = cmap[*bj];
5194         if (col >= cstart) break;
5195         *cam++ = *ba++; bj++;
5196       }
5197       /* diagonal portion of A */
5198       ncols_d = ai[i+1] - ai[i];
5199       for (j=0; j<ncols_d; j++) *cam++ = *aa++;
5200       /* off-diagonal portion of A */
5201       for (j=jo; j<ncols_o; j++) {
5202         *cam++ = *ba++; bj++;
5203       }
5204     }
5205   } else SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONG,"Invalid MatReuse %d",(int)scall);
5206   ierr = PetscLogEventEnd(MAT_Getlocalmat,A,0,0,0);CHKERRQ(ierr);
5207   PetscFunctionReturn(0);
5208 }
5209 
5210 #undef __FUNCT__
5211 #define __FUNCT__ "MatMPIAIJGetLocalMatCondensed"
5212 /*@C
5213      MatMPIAIJGetLocalMatCondensed - Creates a SeqAIJ matrix from an MPIAIJ matrix by taking all its local rows and NON-ZERO columns
5214 
5215     Not Collective
5216 
5217    Input Parameters:
5218 +    A - the matrix
5219 .    scall - either MAT_INITIAL_MATRIX or MAT_REUSE_MATRIX
5220 -    row, col - index sets of rows and columns to extract (or NULL)
5221 
5222    Output Parameter:
5223 .    A_loc - the local sequential matrix generated
5224 
5225     Level: developer
5226 
5227 .seealso: MatGetOwnershipRange(), MatMPIAIJGetLocalMat()
5228 
5229 @*/
5230 PetscErrorCode  MatMPIAIJGetLocalMatCondensed(Mat A,MatReuse scall,IS *row,IS *col,Mat *A_loc)
5231 {
5232   Mat_MPIAIJ     *a=(Mat_MPIAIJ*)A->data;
5233   PetscErrorCode ierr;
5234   PetscInt       i,start,end,ncols,nzA,nzB,*cmap,imark,*idx;
5235   IS             isrowa,iscola;
5236   Mat            *aloc;
5237   PetscBool      match;
5238 
5239   PetscFunctionBegin;
5240   ierr = PetscObjectTypeCompare((PetscObject)A,MATMPIAIJ,&match);CHKERRQ(ierr);
5241   if (!match) SETERRQ(PetscObjectComm((PetscObject)A), PETSC_ERR_SUP,"Requires MPIAIJ matrix as input");
5242   ierr = PetscLogEventBegin(MAT_Getlocalmatcondensed,A,0,0,0);CHKERRQ(ierr);
5243   if (!row) {
5244     start = A->rmap->rstart; end = A->rmap->rend;
5245     ierr  = ISCreateStride(PETSC_COMM_SELF,end-start,start,1,&isrowa);CHKERRQ(ierr);
5246   } else {
5247     isrowa = *row;
5248   }
5249   if (!col) {
5250     start = A->cmap->rstart;
5251     cmap  = a->garray;
5252     nzA   = a->A->cmap->n;
5253     nzB   = a->B->cmap->n;
5254     ierr  = PetscMalloc((nzA+nzB)*sizeof(PetscInt), &idx);CHKERRQ(ierr);
5255     ncols = 0;
5256     for (i=0; i<nzB; i++) {
5257       if (cmap[i] < start) idx[ncols++] = cmap[i];
5258       else break;
5259     }
5260     imark = i;
5261     for (i=0; i<nzA; i++) idx[ncols++] = start + i;
5262     for (i=imark; i<nzB; i++) idx[ncols++] = cmap[i];
5263     ierr = ISCreateGeneral(PETSC_COMM_SELF,ncols,idx,PETSC_OWN_POINTER,&iscola);CHKERRQ(ierr);
5264   } else {
5265     iscola = *col;
5266   }
5267   if (scall != MAT_INITIAL_MATRIX) {
5268     ierr    = PetscMalloc(sizeof(Mat),&aloc);CHKERRQ(ierr);
5269     aloc[0] = *A_loc;
5270   }
5271   ierr   = MatGetSubMatrices(A,1,&isrowa,&iscola,scall,&aloc);CHKERRQ(ierr);
5272   *A_loc = aloc[0];
5273   ierr   = PetscFree(aloc);CHKERRQ(ierr);
5274   if (!row) {
5275     ierr = ISDestroy(&isrowa);CHKERRQ(ierr);
5276   }
5277   if (!col) {
5278     ierr = ISDestroy(&iscola);CHKERRQ(ierr);
5279   }
5280   ierr = PetscLogEventEnd(MAT_Getlocalmatcondensed,A,0,0,0);CHKERRQ(ierr);
5281   PetscFunctionReturn(0);
5282 }
5283 
5284 #undef __FUNCT__
5285 #define __FUNCT__ "MatGetBrowsOfAcols"
5286 /*@C
5287     MatGetBrowsOfAcols - Creates a SeqAIJ matrix by taking rows of B that equal to nonzero columns of local A
5288 
5289     Collective on Mat
5290 
5291    Input Parameters:
5292 +    A,B - the matrices in mpiaij format
5293 .    scall - either MAT_INITIAL_MATRIX or MAT_REUSE_MATRIX
5294 -    rowb, colb - index sets of rows and columns of B to extract (or NULL)
5295 
5296    Output Parameter:
5297 +    rowb, colb - index sets of rows and columns of B to extract
5298 -    B_seq - the sequential matrix generated
5299 
5300     Level: developer
5301 
5302 @*/
5303 PetscErrorCode  MatGetBrowsOfAcols(Mat A,Mat B,MatReuse scall,IS *rowb,IS *colb,Mat *B_seq)
5304 {
5305   Mat_MPIAIJ     *a=(Mat_MPIAIJ*)A->data;
5306   PetscErrorCode ierr;
5307   PetscInt       *idx,i,start,ncols,nzA,nzB,*cmap,imark;
5308   IS             isrowb,iscolb;
5309   Mat            *bseq=NULL;
5310 
5311   PetscFunctionBegin;
5312   if (A->cmap->rstart != B->rmap->rstart || A->cmap->rend != B->rmap->rend) {
5313     SETERRQ4(PETSC_COMM_SELF,PETSC_ERR_ARG_SIZ,"Matrix local dimensions are incompatible, (%D, %D) != (%D,%D)",A->cmap->rstart,A->cmap->rend,B->rmap->rstart,B->rmap->rend);
5314   }
5315   ierr = PetscLogEventBegin(MAT_GetBrowsOfAcols,A,B,0,0);CHKERRQ(ierr);
5316 
5317   if (scall == MAT_INITIAL_MATRIX) {
5318     start = A->cmap->rstart;
5319     cmap  = a->garray;
5320     nzA   = a->A->cmap->n;
5321     nzB   = a->B->cmap->n;
5322     ierr  = PetscMalloc((nzA+nzB)*sizeof(PetscInt), &idx);CHKERRQ(ierr);
5323     ncols = 0;
5324     for (i=0; i<nzB; i++) {  /* row < local row index */
5325       if (cmap[i] < start) idx[ncols++] = cmap[i];
5326       else break;
5327     }
5328     imark = i;
5329     for (i=0; i<nzA; i++) idx[ncols++] = start + i;  /* local rows */
5330     for (i=imark; i<nzB; i++) idx[ncols++] = cmap[i]; /* row > local row index */
5331     ierr = ISCreateGeneral(PETSC_COMM_SELF,ncols,idx,PETSC_OWN_POINTER,&isrowb);CHKERRQ(ierr);
5332     ierr = ISCreateStride(PETSC_COMM_SELF,B->cmap->N,0,1,&iscolb);CHKERRQ(ierr);
5333   } else {
5334     if (!rowb || !colb) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_SUP,"IS rowb and colb must be provided for MAT_REUSE_MATRIX");
5335     isrowb  = *rowb; iscolb = *colb;
5336     ierr    = PetscMalloc(sizeof(Mat),&bseq);CHKERRQ(ierr);
5337     bseq[0] = *B_seq;
5338   }
5339   ierr   = MatGetSubMatrices(B,1,&isrowb,&iscolb,scall,&bseq);CHKERRQ(ierr);
5340   *B_seq = bseq[0];
5341   ierr   = PetscFree(bseq);CHKERRQ(ierr);
5342   if (!rowb) {
5343     ierr = ISDestroy(&isrowb);CHKERRQ(ierr);
5344   } else {
5345     *rowb = isrowb;
5346   }
5347   if (!colb) {
5348     ierr = ISDestroy(&iscolb);CHKERRQ(ierr);
5349   } else {
5350     *colb = iscolb;
5351   }
5352   ierr = PetscLogEventEnd(MAT_GetBrowsOfAcols,A,B,0,0);CHKERRQ(ierr);
5353   PetscFunctionReturn(0);
5354 }
5355 
5356 #undef __FUNCT__
5357 #define __FUNCT__ "MatGetBrowsOfAoCols_MPIAIJ"
5358 /*
5359     MatGetBrowsOfAoCols_MPIAIJ - Creates a SeqAIJ matrix by taking rows of B that equal to nonzero columns
5360     of the OFF-DIAGONAL portion of local A
5361 
5362     Collective on Mat
5363 
5364    Input Parameters:
5365 +    A,B - the matrices in mpiaij format
5366 -    scall - either MAT_INITIAL_MATRIX or MAT_REUSE_MATRIX
5367 
5368    Output Parameter:
5369 +    startsj_s - starting point in B's sending j-arrays, saved for MAT_REUSE (or NULL)
5370 .    startsj_r - starting point in B's receiving j-arrays, saved for MAT_REUSE (or NULL)
5371 .    bufa_ptr - array for sending matrix values, saved for MAT_REUSE (or NULL)
5372 -    B_oth - the sequential matrix generated with size aBn=a->B->cmap->n by B->cmap->N
5373 
5374     Level: developer
5375 
5376 */
5377 PetscErrorCode  MatGetBrowsOfAoCols_MPIAIJ(Mat A,Mat B,MatReuse scall,PetscInt **startsj_s,PetscInt **startsj_r,MatScalar **bufa_ptr,Mat *B_oth)
5378 {
5379   VecScatter_MPI_General *gen_to,*gen_from;
5380   PetscErrorCode         ierr;
5381   Mat_MPIAIJ             *a=(Mat_MPIAIJ*)A->data;
5382   Mat_SeqAIJ             *b_oth;
5383   VecScatter             ctx =a->Mvctx;
5384   MPI_Comm               comm;
5385   PetscMPIInt            *rprocs,*sprocs,tag=((PetscObject)ctx)->tag,rank;
5386   PetscInt               *rowlen,*bufj,*bufJ,ncols,aBn=a->B->cmap->n,row,*b_othi,*b_othj;
5387   PetscScalar            *rvalues,*svalues;
5388   MatScalar              *b_otha,*bufa,*bufA;
5389   PetscInt               i,j,k,l,ll,nrecvs,nsends,nrows,*srow,*rstarts,*rstartsj = 0,*sstarts,*sstartsj,len;
5390   MPI_Request            *rwaits = NULL,*swaits = NULL;
5391   MPI_Status             *sstatus,rstatus;
5392   PetscMPIInt            jj;
5393   PetscInt               *cols,sbs,rbs;
5394   PetscScalar            *vals;
5395 
5396   PetscFunctionBegin;
5397   ierr = PetscObjectGetComm((PetscObject)A,&comm);CHKERRQ(ierr);
5398   if (A->cmap->rstart != B->rmap->rstart || A->cmap->rend != B->rmap->rend) {
5399     SETERRQ4(PETSC_COMM_SELF,PETSC_ERR_ARG_SIZ,"Matrix local dimensions are incompatible, (%d, %d) != (%d,%d)",A->cmap->rstart,A->cmap->rend,B->rmap->rstart,B->rmap->rend);
5400   }
5401   ierr = PetscLogEventBegin(MAT_GetBrowsOfAocols,A,B,0,0);CHKERRQ(ierr);
5402   ierr = MPI_Comm_rank(comm,&rank);CHKERRQ(ierr);
5403 
5404   gen_to   = (VecScatter_MPI_General*)ctx->todata;
5405   gen_from = (VecScatter_MPI_General*)ctx->fromdata;
5406   rvalues  = gen_from->values; /* holds the length of receiving row */
5407   svalues  = gen_to->values;   /* holds the length of sending row */
5408   nrecvs   = gen_from->n;
5409   nsends   = gen_to->n;
5410 
5411   ierr    = PetscMalloc2(nrecvs,MPI_Request,&rwaits,nsends,MPI_Request,&swaits);CHKERRQ(ierr);
5412   srow    = gen_to->indices;    /* local row index to be sent */
5413   sstarts = gen_to->starts;
5414   sprocs  = gen_to->procs;
5415   sstatus = gen_to->sstatus;
5416   sbs     = gen_to->bs;
5417   rstarts = gen_from->starts;
5418   rprocs  = gen_from->procs;
5419   rbs     = gen_from->bs;
5420 
5421   if (!startsj_s || !bufa_ptr) scall = MAT_INITIAL_MATRIX;
5422   if (scall == MAT_INITIAL_MATRIX) {
5423     /* i-array */
5424     /*---------*/
5425     /*  post receives */
5426     for (i=0; i<nrecvs; i++) {
5427       rowlen = (PetscInt*)rvalues + rstarts[i]*rbs;
5428       nrows  = (rstarts[i+1]-rstarts[i])*rbs; /* num of indices to be received */
5429       ierr   = MPI_Irecv(rowlen,nrows,MPIU_INT,rprocs[i],tag,comm,rwaits+i);CHKERRQ(ierr);
5430     }
5431 
5432     /* pack the outgoing message */
5433     ierr = PetscMalloc2(nsends+1,PetscInt,&sstartsj,nrecvs+1,PetscInt,&rstartsj);CHKERRQ(ierr);
5434 
5435     sstartsj[0] = 0;
5436     rstartsj[0] = 0;
5437     len         = 0; /* total length of j or a array to be sent */
5438     k           = 0;
5439     for (i=0; i<nsends; i++) {
5440       rowlen = (PetscInt*)svalues + sstarts[i]*sbs;
5441       nrows  = sstarts[i+1]-sstarts[i]; /* num of block rows */
5442       for (j=0; j<nrows; j++) {
5443         row = srow[k] + B->rmap->range[rank]; /* global row idx */
5444         for (l=0; l<sbs; l++) {
5445           ierr = MatGetRow_MPIAIJ(B,row+l,&ncols,NULL,NULL);CHKERRQ(ierr); /* rowlength */
5446 
5447           rowlen[j*sbs+l] = ncols;
5448 
5449           len += ncols;
5450           ierr = MatRestoreRow_MPIAIJ(B,row+l,&ncols,NULL,NULL);CHKERRQ(ierr);
5451         }
5452         k++;
5453       }
5454       ierr = MPI_Isend(rowlen,nrows*sbs,MPIU_INT,sprocs[i],tag,comm,swaits+i);CHKERRQ(ierr);
5455 
5456       sstartsj[i+1] = len;  /* starting point of (i+1)-th outgoing msg in bufj and bufa */
5457     }
5458     /* recvs and sends of i-array are completed */
5459     i = nrecvs;
5460     while (i--) {
5461       ierr = MPI_Waitany(nrecvs,rwaits,&jj,&rstatus);CHKERRQ(ierr);
5462     }
5463     if (nsends) {ierr = MPI_Waitall(nsends,swaits,sstatus);CHKERRQ(ierr);}
5464 
5465     /* allocate buffers for sending j and a arrays */
5466     ierr = PetscMalloc((len+1)*sizeof(PetscInt),&bufj);CHKERRQ(ierr);
5467     ierr = PetscMalloc((len+1)*sizeof(PetscScalar),&bufa);CHKERRQ(ierr);
5468 
5469     /* create i-array of B_oth */
5470     ierr = PetscMalloc((aBn+2)*sizeof(PetscInt),&b_othi);CHKERRQ(ierr);
5471 
5472     b_othi[0] = 0;
5473     len       = 0; /* total length of j or a array to be received */
5474     k         = 0;
5475     for (i=0; i<nrecvs; i++) {
5476       rowlen = (PetscInt*)rvalues + rstarts[i]*rbs;
5477       nrows  = rbs*(rstarts[i+1]-rstarts[i]); /* num of rows to be recieved */
5478       for (j=0; j<nrows; j++) {
5479         b_othi[k+1] = b_othi[k] + rowlen[j];
5480         len        += rowlen[j]; k++;
5481       }
5482       rstartsj[i+1] = len; /* starting point of (i+1)-th incoming msg in bufj and bufa */
5483     }
5484 
5485     /* allocate space for j and a arrrays of B_oth */
5486     ierr = PetscMalloc((b_othi[aBn]+1)*sizeof(PetscInt),&b_othj);CHKERRQ(ierr);
5487     ierr = PetscMalloc((b_othi[aBn]+1)*sizeof(MatScalar),&b_otha);CHKERRQ(ierr);
5488 
5489     /* j-array */
5490     /*---------*/
5491     /*  post receives of j-array */
5492     for (i=0; i<nrecvs; i++) {
5493       nrows = rstartsj[i+1]-rstartsj[i]; /* length of the msg received */
5494       ierr  = MPI_Irecv(b_othj+rstartsj[i],nrows,MPIU_INT,rprocs[i],tag,comm,rwaits+i);CHKERRQ(ierr);
5495     }
5496 
5497     /* pack the outgoing message j-array */
5498     k = 0;
5499     for (i=0; i<nsends; i++) {
5500       nrows = sstarts[i+1]-sstarts[i]; /* num of block rows */
5501       bufJ  = bufj+sstartsj[i];
5502       for (j=0; j<nrows; j++) {
5503         row = srow[k++] + B->rmap->range[rank];  /* global row idx */
5504         for (ll=0; ll<sbs; ll++) {
5505           ierr = MatGetRow_MPIAIJ(B,row+ll,&ncols,&cols,NULL);CHKERRQ(ierr);
5506           for (l=0; l<ncols; l++) {
5507             *bufJ++ = cols[l];
5508           }
5509           ierr = MatRestoreRow_MPIAIJ(B,row+ll,&ncols,&cols,NULL);CHKERRQ(ierr);
5510         }
5511       }
5512       ierr = MPI_Isend(bufj+sstartsj[i],sstartsj[i+1]-sstartsj[i],MPIU_INT,sprocs[i],tag,comm,swaits+i);CHKERRQ(ierr);
5513     }
5514 
5515     /* recvs and sends of j-array are completed */
5516     i = nrecvs;
5517     while (i--) {
5518       ierr = MPI_Waitany(nrecvs,rwaits,&jj,&rstatus);CHKERRQ(ierr);
5519     }
5520     if (nsends) {ierr = MPI_Waitall(nsends,swaits,sstatus);CHKERRQ(ierr);}
5521   } else if (scall == MAT_REUSE_MATRIX) {
5522     sstartsj = *startsj_s;
5523     rstartsj = *startsj_r;
5524     bufa     = *bufa_ptr;
5525     b_oth    = (Mat_SeqAIJ*)(*B_oth)->data;
5526     b_otha   = b_oth->a;
5527   } else SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE, "Matrix P does not posses an object container");
5528 
5529   /* a-array */
5530   /*---------*/
5531   /*  post receives of a-array */
5532   for (i=0; i<nrecvs; i++) {
5533     nrows = rstartsj[i+1]-rstartsj[i]; /* length of the msg received */
5534     ierr  = MPI_Irecv(b_otha+rstartsj[i],nrows,MPIU_SCALAR,rprocs[i],tag,comm,rwaits+i);CHKERRQ(ierr);
5535   }
5536 
5537   /* pack the outgoing message a-array */
5538   k = 0;
5539   for (i=0; i<nsends; i++) {
5540     nrows = sstarts[i+1]-sstarts[i]; /* num of block rows */
5541     bufA  = bufa+sstartsj[i];
5542     for (j=0; j<nrows; j++) {
5543       row = srow[k++] + B->rmap->range[rank];  /* global row idx */
5544       for (ll=0; ll<sbs; ll++) {
5545         ierr = MatGetRow_MPIAIJ(B,row+ll,&ncols,NULL,&vals);CHKERRQ(ierr);
5546         for (l=0; l<ncols; l++) {
5547           *bufA++ = vals[l];
5548         }
5549         ierr = MatRestoreRow_MPIAIJ(B,row+ll,&ncols,NULL,&vals);CHKERRQ(ierr);
5550       }
5551     }
5552     ierr = MPI_Isend(bufa+sstartsj[i],sstartsj[i+1]-sstartsj[i],MPIU_SCALAR,sprocs[i],tag,comm,swaits+i);CHKERRQ(ierr);
5553   }
5554   /* recvs and sends of a-array are completed */
5555   i = nrecvs;
5556   while (i--) {
5557     ierr = MPI_Waitany(nrecvs,rwaits,&jj,&rstatus);CHKERRQ(ierr);
5558   }
5559   if (nsends) {ierr = MPI_Waitall(nsends,swaits,sstatus);CHKERRQ(ierr);}
5560   ierr = PetscFree2(rwaits,swaits);CHKERRQ(ierr);
5561 
5562   if (scall == MAT_INITIAL_MATRIX) {
5563     /* put together the new matrix */
5564     ierr = MatCreateSeqAIJWithArrays(PETSC_COMM_SELF,aBn,B->cmap->N,b_othi,b_othj,b_otha,B_oth);CHKERRQ(ierr);
5565 
5566     /* MatCreateSeqAIJWithArrays flags matrix so PETSc doesn't free the user's arrays. */
5567     /* Since these are PETSc arrays, change flags to free them as necessary. */
5568     b_oth          = (Mat_SeqAIJ*)(*B_oth)->data;
5569     b_oth->free_a  = PETSC_TRUE;
5570     b_oth->free_ij = PETSC_TRUE;
5571     b_oth->nonew   = 0;
5572 
5573     ierr = PetscFree(bufj);CHKERRQ(ierr);
5574     if (!startsj_s || !bufa_ptr) {
5575       ierr = PetscFree2(sstartsj,rstartsj);CHKERRQ(ierr);
5576       ierr = PetscFree(bufa_ptr);CHKERRQ(ierr);
5577     } else {
5578       *startsj_s = sstartsj;
5579       *startsj_r = rstartsj;
5580       *bufa_ptr  = bufa;
5581     }
5582   }
5583   ierr = PetscLogEventEnd(MAT_GetBrowsOfAocols,A,B,0,0);CHKERRQ(ierr);
5584   PetscFunctionReturn(0);
5585 }
5586 
5587 #undef __FUNCT__
5588 #define __FUNCT__ "MatGetCommunicationStructs"
5589 /*@C
5590   MatGetCommunicationStructs - Provides access to the communication structures used in matrix-vector multiplication.
5591 
5592   Not Collective
5593 
5594   Input Parameters:
5595 . A - The matrix in mpiaij format
5596 
5597   Output Parameter:
5598 + lvec - The local vector holding off-process values from the argument to a matrix-vector product
5599 . colmap - A map from global column index to local index into lvec
5600 - multScatter - A scatter from the argument of a matrix-vector product to lvec
5601 
5602   Level: developer
5603 
5604 @*/
5605 #if defined(PETSC_USE_CTABLE)
5606 PetscErrorCode  MatGetCommunicationStructs(Mat A, Vec *lvec, PetscTable *colmap, VecScatter *multScatter)
5607 #else
5608 PetscErrorCode  MatGetCommunicationStructs(Mat A, Vec *lvec, PetscInt *colmap[], VecScatter *multScatter)
5609 #endif
5610 {
5611   Mat_MPIAIJ *a;
5612 
5613   PetscFunctionBegin;
5614   PetscValidHeaderSpecific(A, MAT_CLASSID, 1);
5615   PetscValidPointer(lvec, 2);
5616   PetscValidPointer(colmap, 3);
5617   PetscValidPointer(multScatter, 4);
5618   a = (Mat_MPIAIJ*) A->data;
5619   if (lvec) *lvec = a->lvec;
5620   if (colmap) *colmap = a->colmap;
5621   if (multScatter) *multScatter = a->Mvctx;
5622   PetscFunctionReturn(0);
5623 }
5624 
5625 PETSC_EXTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJCRL(Mat,MatType,MatReuse,Mat*);
5626 PETSC_EXTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJPERM(Mat,MatType,MatReuse,Mat*);
5627 PETSC_EXTERN PetscErrorCode MatConvert_MPIAIJ_MPISBAIJ(Mat,MatType,MatReuse,Mat*);
5628 
5629 #undef __FUNCT__
5630 #define __FUNCT__ "MatMatMultNumeric_MPIDense_MPIAIJ"
5631 /*
5632     Computes (B'*A')' since computing B*A directly is untenable
5633 
5634                n                       p                          p
5635         (              )       (              )         (                  )
5636       m (      A       )  *  n (       B      )   =   m (         C        )
5637         (              )       (              )         (                  )
5638 
5639 */
5640 PetscErrorCode MatMatMultNumeric_MPIDense_MPIAIJ(Mat A,Mat B,Mat C)
5641 {
5642   PetscErrorCode ierr;
5643   Mat            At,Bt,Ct;
5644 
5645   PetscFunctionBegin;
5646   ierr = MatTranspose(A,MAT_INITIAL_MATRIX,&At);CHKERRQ(ierr);
5647   ierr = MatTranspose(B,MAT_INITIAL_MATRIX,&Bt);CHKERRQ(ierr);
5648   ierr = MatMatMult(Bt,At,MAT_INITIAL_MATRIX,1.0,&Ct);CHKERRQ(ierr);
5649   ierr = MatDestroy(&At);CHKERRQ(ierr);
5650   ierr = MatDestroy(&Bt);CHKERRQ(ierr);
5651   ierr = MatTranspose(Ct,MAT_REUSE_MATRIX,&C);CHKERRQ(ierr);
5652   ierr = MatDestroy(&Ct);CHKERRQ(ierr);
5653   PetscFunctionReturn(0);
5654 }
5655 
5656 #undef __FUNCT__
5657 #define __FUNCT__ "MatMatMultSymbolic_MPIDense_MPIAIJ"
5658 PetscErrorCode MatMatMultSymbolic_MPIDense_MPIAIJ(Mat A,Mat B,PetscReal fill,Mat *C)
5659 {
5660   PetscErrorCode ierr;
5661   PetscInt       m=A->rmap->n,n=B->cmap->n;
5662   Mat            Cmat;
5663 
5664   PetscFunctionBegin;
5665   if (A->cmap->n != B->rmap->n) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_SIZ,"A->cmap->n %d != B->rmap->n %d\n",A->cmap->n,B->rmap->n);
5666   ierr = MatCreate(PetscObjectComm((PetscObject)A),&Cmat);CHKERRQ(ierr);
5667   ierr = MatSetSizes(Cmat,m,n,PETSC_DETERMINE,PETSC_DETERMINE);CHKERRQ(ierr);
5668   ierr = MatSetBlockSizes(Cmat,A->rmap->bs,B->cmap->bs);CHKERRQ(ierr);
5669   ierr = MatSetType(Cmat,MATMPIDENSE);CHKERRQ(ierr);
5670   ierr = MatMPIDenseSetPreallocation(Cmat,NULL);CHKERRQ(ierr);
5671   ierr = MatAssemblyBegin(Cmat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
5672   ierr = MatAssemblyEnd(Cmat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
5673 
5674   Cmat->ops->matmultnumeric = MatMatMultNumeric_MPIDense_MPIAIJ;
5675 
5676   *C = Cmat;
5677   PetscFunctionReturn(0);
5678 }
5679 
5680 /* ----------------------------------------------------------------*/
5681 #undef __FUNCT__
5682 #define __FUNCT__ "MatMatMult_MPIDense_MPIAIJ"
5683 PetscErrorCode MatMatMult_MPIDense_MPIAIJ(Mat A,Mat B,MatReuse scall,PetscReal fill,Mat *C)
5684 {
5685   PetscErrorCode ierr;
5686 
5687   PetscFunctionBegin;
5688   if (scall == MAT_INITIAL_MATRIX) {
5689     ierr = PetscLogEventBegin(MAT_MatMultSymbolic,A,B,0,0);CHKERRQ(ierr);
5690     ierr = MatMatMultSymbolic_MPIDense_MPIAIJ(A,B,fill,C);CHKERRQ(ierr);
5691     ierr = PetscLogEventEnd(MAT_MatMultSymbolic,A,B,0,0);CHKERRQ(ierr);
5692   }
5693   ierr = PetscLogEventBegin(MAT_MatMultNumeric,A,B,0,0);CHKERRQ(ierr);
5694   ierr = MatMatMultNumeric_MPIDense_MPIAIJ(A,B,*C);CHKERRQ(ierr);
5695   ierr = PetscLogEventEnd(MAT_MatMultNumeric,A,B,0,0);CHKERRQ(ierr);
5696   PetscFunctionReturn(0);
5697 }
5698 
5699 #if defined(PETSC_HAVE_MUMPS)
5700 PETSC_EXTERN PetscErrorCode MatGetFactor_aij_mumps(Mat,MatFactorType,Mat*);
5701 #endif
5702 #if defined(PETSC_HAVE_PASTIX)
5703 PETSC_EXTERN PetscErrorCode MatGetFactor_mpiaij_pastix(Mat,MatFactorType,Mat*);
5704 #endif
5705 #if defined(PETSC_HAVE_SUPERLU_DIST)
5706 PETSC_EXTERN PetscErrorCode MatGetFactor_mpiaij_superlu_dist(Mat,MatFactorType,Mat*);
5707 #endif
5708 #if defined(PETSC_HAVE_CLIQUE)
5709 PETSC_EXTERN PetscErrorCode MatGetFactor_aij_clique(Mat,MatFactorType,Mat*);
5710 #endif
5711 
5712 /*MC
5713    MATMPIAIJ - MATMPIAIJ = "mpiaij" - A matrix type to be used for parallel sparse matrices.
5714 
5715    Options Database Keys:
5716 . -mat_type mpiaij - sets the matrix type to "mpiaij" during a call to MatSetFromOptions()
5717 
5718   Level: beginner
5719 
5720 .seealso: MatCreateAIJ()
5721 M*/
5722 
5723 #undef __FUNCT__
5724 #define __FUNCT__ "MatCreate_MPIAIJ"
5725 PETSC_EXTERN PetscErrorCode MatCreate_MPIAIJ(Mat B)
5726 {
5727   Mat_MPIAIJ     *b;
5728   PetscErrorCode ierr;
5729   PetscMPIInt    size;
5730 
5731   PetscFunctionBegin;
5732   ierr = MPI_Comm_size(PetscObjectComm((PetscObject)B),&size);CHKERRQ(ierr);
5733 
5734   ierr          = PetscNewLog(B,Mat_MPIAIJ,&b);CHKERRQ(ierr);
5735   B->data       = (void*)b;
5736   ierr          = PetscMemcpy(B->ops,&MatOps_Values,sizeof(struct _MatOps));CHKERRQ(ierr);
5737   B->assembled  = PETSC_FALSE;
5738   B->insertmode = NOT_SET_VALUES;
5739   b->size       = size;
5740 
5741   ierr = MPI_Comm_rank(PetscObjectComm((PetscObject)B),&b->rank);CHKERRQ(ierr);
5742 
5743   /* build cache for off array entries formed */
5744   ierr = MatStashCreate_Private(PetscObjectComm((PetscObject)B),1,&B->stash);CHKERRQ(ierr);
5745 
5746   b->donotstash  = PETSC_FALSE;
5747   b->colmap      = 0;
5748   b->garray      = 0;
5749   b->roworiented = PETSC_TRUE;
5750 
5751   /* stuff used for matrix vector multiply */
5752   b->lvec  = NULL;
5753   b->Mvctx = NULL;
5754 
5755   /* stuff for MatGetRow() */
5756   b->rowindices   = 0;
5757   b->rowvalues    = 0;
5758   b->getrowactive = PETSC_FALSE;
5759 
5760   /* flexible pointer used in CUSP/CUSPARSE classes */
5761   b->spptr = NULL;
5762 
5763 #if defined(PETSC_HAVE_MUMPS)
5764   ierr = PetscObjectComposeFunction((PetscObject)B,"MatGetFactor_mumps_C",MatGetFactor_aij_mumps);CHKERRQ(ierr);
5765 #endif
5766 #if defined(PETSC_HAVE_PASTIX)
5767   ierr = PetscObjectComposeFunction((PetscObject)B,"MatGetFactor_pastix_C",MatGetFactor_mpiaij_pastix);CHKERRQ(ierr);
5768 #endif
5769 #if defined(PETSC_HAVE_SUPERLU_DIST)
5770   ierr = PetscObjectComposeFunction((PetscObject)B,"MatGetFactor_superlu_dist_C",MatGetFactor_mpiaij_superlu_dist);CHKERRQ(ierr);
5771 #endif
5772 #if defined(PETSC_HAVE_CLIQUE)
5773   ierr = PetscObjectComposeFunction((PetscObject)B,"MatGetFactor_clique_C",MatGetFactor_aij_clique);CHKERRQ(ierr);
5774 #endif
5775   ierr = PetscObjectComposeFunction((PetscObject)B,"MatStoreValues_C",MatStoreValues_MPIAIJ);CHKERRQ(ierr);
5776   ierr = PetscObjectComposeFunction((PetscObject)B,"MatRetrieveValues_C",MatRetrieveValues_MPIAIJ);CHKERRQ(ierr);
5777   ierr = PetscObjectComposeFunction((PetscObject)B,"MatGetDiagonalBlock_C",MatGetDiagonalBlock_MPIAIJ);CHKERRQ(ierr);
5778   ierr = PetscObjectComposeFunction((PetscObject)B,"MatIsTranspose_C",MatIsTranspose_MPIAIJ);CHKERRQ(ierr);
5779   ierr = PetscObjectComposeFunction((PetscObject)B,"MatMPIAIJSetPreallocation_C",MatMPIAIJSetPreallocation_MPIAIJ);CHKERRQ(ierr);
5780   ierr = PetscObjectComposeFunction((PetscObject)B,"MatMPIAIJSetPreallocationCSR_C",MatMPIAIJSetPreallocationCSR_MPIAIJ);CHKERRQ(ierr);
5781   ierr = PetscObjectComposeFunction((PetscObject)B,"MatDiagonalScaleLocal_C",MatDiagonalScaleLocal_MPIAIJ);CHKERRQ(ierr);
5782   ierr = PetscObjectComposeFunction((PetscObject)B,"MatConvert_mpiaij_mpiaijperm_C",MatConvert_MPIAIJ_MPIAIJPERM);CHKERRQ(ierr);
5783   ierr = PetscObjectComposeFunction((PetscObject)B,"MatConvert_mpiaij_mpiaijcrl_C",MatConvert_MPIAIJ_MPIAIJCRL);CHKERRQ(ierr);
5784   ierr = PetscObjectComposeFunction((PetscObject)B,"MatConvert_mpiaij_mpisbaij_C",MatConvert_MPIAIJ_MPISBAIJ);CHKERRQ(ierr);
5785   ierr = PetscObjectComposeFunction((PetscObject)B,"MatMatMult_mpidense_mpiaij_C",MatMatMult_MPIDense_MPIAIJ);CHKERRQ(ierr);
5786   ierr = PetscObjectComposeFunction((PetscObject)B,"MatMatMultSymbolic_mpidense_mpiaij_C",MatMatMultSymbolic_MPIDense_MPIAIJ);CHKERRQ(ierr);
5787   ierr = PetscObjectComposeFunction((PetscObject)B,"MatMatMultNumeric_mpidense_mpiaij_C",MatMatMultNumeric_MPIDense_MPIAIJ);CHKERRQ(ierr);
5788   ierr = PetscObjectChangeTypeName((PetscObject)B,MATMPIAIJ);CHKERRQ(ierr);
5789   PetscFunctionReturn(0);
5790 }
5791 
5792 #undef __FUNCT__
5793 #define __FUNCT__ "MatCreateMPIAIJWithSplitArrays"
5794 /*@
5795      MatCreateMPIAIJWithSplitArrays - creates a MPI AIJ matrix using arrays that contain the "diagonal"
5796          and "off-diagonal" part of the matrix in CSR format.
5797 
5798    Collective on MPI_Comm
5799 
5800    Input Parameters:
5801 +  comm - MPI communicator
5802 .  m - number of local rows (Cannot be PETSC_DECIDE)
5803 .  n - This value should be the same as the local size used in creating the
5804        x vector for the matrix-vector product y = Ax. (or PETSC_DECIDE to have
5805        calculated if N is given) For square matrices n is almost always m.
5806 .  M - number of global rows (or PETSC_DETERMINE to have calculated if m is given)
5807 .  N - number of global columns (or PETSC_DETERMINE to have calculated if n is given)
5808 .   i - row indices for "diagonal" portion of matrix
5809 .   j - column indices
5810 .   a - matrix values
5811 .   oi - row indices for "off-diagonal" portion of matrix
5812 .   oj - column indices
5813 -   oa - matrix values
5814 
5815    Output Parameter:
5816 .   mat - the matrix
5817 
5818    Level: advanced
5819 
5820    Notes:
5821        The i, j, and a arrays ARE NOT copied by this routine into the internal format used by PETSc. The user
5822        must free the arrays once the matrix has been destroyed and not before.
5823 
5824        The i and j indices are 0 based
5825 
5826        See MatCreateAIJ() for the definition of "diagonal" and "off-diagonal" portion of the matrix
5827 
5828        This sets local rows and cannot be used to set off-processor values.
5829 
5830        Use of this routine is discouraged because it is inflexible and cumbersome to use. It is extremely rare that a
5831        legacy application natively assembles into exactly this split format. The code to do so is nontrivial and does
5832        not easily support in-place reassembly. It is recommended to use MatSetValues() (or a variant thereof) because
5833        the resulting assembly is easier to implement, will work with any matrix format, and the user does not have to
5834        keep track of the underlying array. Use MatSetOption(A,MAT_IGNORE_OFF_PROC_ENTRIES,PETSC_TRUE) to disable all
5835        communication if it is known that only local entries will be set.
5836 
5837 .keywords: matrix, aij, compressed row, sparse, parallel
5838 
5839 .seealso: MatCreate(), MatCreateSeqAIJ(), MatSetValues(), MatMPIAIJSetPreallocation(), MatMPIAIJSetPreallocationCSR(),
5840           MPIAIJ, MatCreateAIJ(), MatCreateMPIAIJWithArrays()
5841 @*/
5842 PetscErrorCode  MatCreateMPIAIJWithSplitArrays(MPI_Comm comm,PetscInt m,PetscInt n,PetscInt M,PetscInt N,PetscInt i[],PetscInt j[],PetscScalar a[],PetscInt oi[], PetscInt oj[],PetscScalar oa[],Mat *mat)
5843 {
5844   PetscErrorCode ierr;
5845   Mat_MPIAIJ     *maij;
5846 
5847   PetscFunctionBegin;
5848   if (m < 0) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"local number of rows (m) cannot be PETSC_DECIDE, or negative");
5849   if (i[0]) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"i (row indices) must start with 0");
5850   if (oi[0]) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"oi (row indices) must start with 0");
5851   ierr = MatCreate(comm,mat);CHKERRQ(ierr);
5852   ierr = MatSetSizes(*mat,m,n,M,N);CHKERRQ(ierr);
5853   ierr = MatSetType(*mat,MATMPIAIJ);CHKERRQ(ierr);
5854   maij = (Mat_MPIAIJ*) (*mat)->data;
5855 
5856   (*mat)->preallocated = PETSC_TRUE;
5857 
5858   ierr = PetscLayoutSetUp((*mat)->rmap);CHKERRQ(ierr);
5859   ierr = PetscLayoutSetUp((*mat)->cmap);CHKERRQ(ierr);
5860 
5861   ierr = MatCreateSeqAIJWithArrays(PETSC_COMM_SELF,m,n,i,j,a,&maij->A);CHKERRQ(ierr);
5862   ierr = MatCreateSeqAIJWithArrays(PETSC_COMM_SELF,m,(*mat)->cmap->N,oi,oj,oa,&maij->B);CHKERRQ(ierr);
5863 
5864   ierr = MatAssemblyBegin(maij->A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
5865   ierr = MatAssemblyEnd(maij->A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
5866   ierr = MatAssemblyBegin(maij->B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
5867   ierr = MatAssemblyEnd(maij->B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
5868 
5869   ierr = MatAssemblyBegin(*mat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
5870   ierr = MatAssemblyEnd(*mat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
5871   ierr = MatSetOption(*mat,MAT_NEW_NONZERO_LOCATION_ERR,PETSC_TRUE);CHKERRQ(ierr);
5872   PetscFunctionReturn(0);
5873 }
5874 
5875 /*
5876     Special version for direct calls from Fortran
5877 */
5878 #include <petsc-private/fortranimpl.h>
5879 
5880 #if defined(PETSC_HAVE_FORTRAN_CAPS)
5881 #define matsetvaluesmpiaij_ MATSETVALUESMPIAIJ
5882 #elif !defined(PETSC_HAVE_FORTRAN_UNDERSCORE)
5883 #define matsetvaluesmpiaij_ matsetvaluesmpiaij
5884 #endif
5885 
5886 /* Change these macros so can be used in void function */
5887 #undef CHKERRQ
5888 #define CHKERRQ(ierr) CHKERRABORT(PETSC_COMM_WORLD,ierr)
5889 #undef SETERRQ2
5890 #define SETERRQ2(comm,ierr,b,c,d) CHKERRABORT(comm,ierr)
5891 #undef SETERRQ3
5892 #define SETERRQ3(comm,ierr,b,c,d,e) CHKERRABORT(comm,ierr)
5893 #undef SETERRQ
5894 #define SETERRQ(c,ierr,b) CHKERRABORT(c,ierr)
5895 
5896 #undef __FUNCT__
5897 #define __FUNCT__ "matsetvaluesmpiaij_"
5898 PETSC_EXTERN void PETSC_STDCALL matsetvaluesmpiaij_(Mat *mmat,PetscInt *mm,const PetscInt im[],PetscInt *mn,const PetscInt in[],const PetscScalar v[],InsertMode *maddv,PetscErrorCode *_ierr)
5899 {
5900   Mat            mat  = *mmat;
5901   PetscInt       m    = *mm, n = *mn;
5902   InsertMode     addv = *maddv;
5903   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
5904   PetscScalar    value;
5905   PetscErrorCode ierr;
5906 
5907   MatCheckPreallocated(mat,1);
5908   if (mat->insertmode == NOT_SET_VALUES) mat->insertmode = addv;
5909 
5910 #if defined(PETSC_USE_DEBUG)
5911   else if (mat->insertmode != addv) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"Cannot mix add values and insert values");
5912 #endif
5913   {
5914     PetscInt  i,j,rstart  = mat->rmap->rstart,rend = mat->rmap->rend;
5915     PetscInt  cstart      = mat->cmap->rstart,cend = mat->cmap->rend,row,col;
5916     PetscBool roworiented = aij->roworiented;
5917 
5918     /* Some Variables required in the macro */
5919     Mat        A                 = aij->A;
5920     Mat_SeqAIJ *a                = (Mat_SeqAIJ*)A->data;
5921     PetscInt   *aimax            = a->imax,*ai = a->i,*ailen = a->ilen,*aj = a->j;
5922     MatScalar  *aa               = a->a;
5923     PetscBool  ignorezeroentries = (((a->ignorezeroentries)&&(addv==ADD_VALUES)) ? PETSC_TRUE : PETSC_FALSE);
5924     Mat        B                 = aij->B;
5925     Mat_SeqAIJ *b                = (Mat_SeqAIJ*)B->data;
5926     PetscInt   *bimax            = b->imax,*bi = b->i,*bilen = b->ilen,*bj = b->j,bm = aij->B->rmap->n,am = aij->A->rmap->n;
5927     MatScalar  *ba               = b->a;
5928 
5929     PetscInt  *rp1,*rp2,ii,nrow1,nrow2,_i,rmax1,rmax2,N,low1,high1,low2,high2,t,lastcol1,lastcol2;
5930     PetscInt  nonew = a->nonew;
5931     MatScalar *ap1,*ap2;
5932 
5933     PetscFunctionBegin;
5934     for (i=0; i<m; i++) {
5935       if (im[i] < 0) continue;
5936 #if defined(PETSC_USE_DEBUG)
5937       if (im[i] >= mat->rmap->N) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Row too large: row %D max %D",im[i],mat->rmap->N-1);
5938 #endif
5939       if (im[i] >= rstart && im[i] < rend) {
5940         row      = im[i] - rstart;
5941         lastcol1 = -1;
5942         rp1      = aj + ai[row];
5943         ap1      = aa + ai[row];
5944         rmax1    = aimax[row];
5945         nrow1    = ailen[row];
5946         low1     = 0;
5947         high1    = nrow1;
5948         lastcol2 = -1;
5949         rp2      = bj + bi[row];
5950         ap2      = ba + bi[row];
5951         rmax2    = bimax[row];
5952         nrow2    = bilen[row];
5953         low2     = 0;
5954         high2    = nrow2;
5955 
5956         for (j=0; j<n; j++) {
5957           if (roworiented) value = v[i*n+j];
5958           else value = v[i+j*m];
5959           if (ignorezeroentries && value == 0.0 && (addv == ADD_VALUES)) continue;
5960           if (in[j] >= cstart && in[j] < cend) {
5961             col = in[j] - cstart;
5962             MatSetValues_SeqAIJ_A_Private(row,col,value,addv);
5963           } else if (in[j] < 0) continue;
5964 #if defined(PETSC_USE_DEBUG)
5965           else if (in[j] >= mat->cmap->N) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Column too large: col %D max %D",in[j],mat->cmap->N-1);
5966 #endif
5967           else {
5968             if (mat->was_assembled) {
5969               if (!aij->colmap) {
5970                 ierr = MatCreateColmap_MPIAIJ_Private(mat);CHKERRQ(ierr);
5971               }
5972 #if defined(PETSC_USE_CTABLE)
5973               ierr = PetscTableFind(aij->colmap,in[j]+1,&col);CHKERRQ(ierr);
5974               col--;
5975 #else
5976               col = aij->colmap[in[j]] - 1;
5977 #endif
5978               if (col < 0 && !((Mat_SeqAIJ*)(aij->A->data))->nonew) {
5979                 ierr = MatDisAssemble_MPIAIJ(mat);CHKERRQ(ierr);
5980                 col  =  in[j];
5981                 /* Reinitialize the variables required by MatSetValues_SeqAIJ_B_Private() */
5982                 B     = aij->B;
5983                 b     = (Mat_SeqAIJ*)B->data;
5984                 bimax = b->imax; bi = b->i; bilen = b->ilen; bj = b->j;
5985                 rp2   = bj + bi[row];
5986                 ap2   = ba + bi[row];
5987                 rmax2 = bimax[row];
5988                 nrow2 = bilen[row];
5989                 low2  = 0;
5990                 high2 = nrow2;
5991                 bm    = aij->B->rmap->n;
5992                 ba    = b->a;
5993               }
5994             } else col = in[j];
5995             MatSetValues_SeqAIJ_B_Private(row,col,value,addv);
5996           }
5997         }
5998       } else if (!aij->donotstash) {
5999         if (roworiented) {
6000           ierr = MatStashValuesRow_Private(&mat->stash,im[i],n,in,v+i*n,(PetscBool)(ignorezeroentries && (addv == ADD_VALUES)));CHKERRQ(ierr);
6001         } else {
6002           ierr = MatStashValuesCol_Private(&mat->stash,im[i],n,in,v+i,m,(PetscBool)(ignorezeroentries && (addv == ADD_VALUES)));CHKERRQ(ierr);
6003         }
6004       }
6005     }
6006   }
6007   PetscFunctionReturnVoid();
6008 }
6009 
6010