xref: /petsc/src/mat/impls/aij/mpi/mpiaij.c (revision 9c8f2541a5996aa8eae70f697bc10dd8da5bda98)
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,MPIU_SUM,PetscObjectComm((PetscObject)M));CHKERRQ(ierr);
80   if (!n0rows) PetscFunctionReturn(0);
81   ierr = PetscMalloc1((M->rmap->n-cnt),&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__ "MatDiagonalSet_MPIAIJ"
109 PetscErrorCode  MatDiagonalSet_MPIAIJ(Mat Y,Vec D,InsertMode is)
110 {
111   PetscErrorCode    ierr;
112   Mat_MPIAIJ        *aij = (Mat_MPIAIJ*) Y->data;
113 
114   PetscFunctionBegin;
115   if (Y->assembled && Y->rmap->rstart == Y->cmap->rstart && Y->rmap->rend == Y->cmap->rend) {
116     ierr = MatDiagonalSet(aij->A,D,is);CHKERRQ(ierr);
117   } else {
118     ierr = MatDiagonalSet_Default(Y,D,is);CHKERRQ(ierr);
119   }
120   PetscFunctionReturn(0);
121 }
122 
123 
124 #undef __FUNCT__
125 #define __FUNCT__ "MatFindZeroDiagonals_MPIAIJ"
126 PetscErrorCode MatFindZeroDiagonals_MPIAIJ(Mat M,IS *zrows)
127 {
128   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)M->data;
129   PetscErrorCode ierr;
130   PetscInt       i,rstart,nrows,*rows;
131 
132   PetscFunctionBegin;
133   *zrows = NULL;
134   ierr   = MatFindZeroDiagonals_SeqAIJ_Private(aij->A,&nrows,&rows);CHKERRQ(ierr);
135   ierr   = MatGetOwnershipRange(M,&rstart,NULL);CHKERRQ(ierr);
136   for (i=0; i<nrows; i++) rows[i] += rstart;
137   ierr = ISCreateGeneral(PetscObjectComm((PetscObject)M),nrows,rows,PETSC_OWN_POINTER,zrows);CHKERRQ(ierr);
138   PetscFunctionReturn(0);
139 }
140 
141 #undef __FUNCT__
142 #define __FUNCT__ "MatGetColumnNorms_MPIAIJ"
143 PetscErrorCode MatGetColumnNorms_MPIAIJ(Mat A,NormType type,PetscReal *norms)
144 {
145   PetscErrorCode ierr;
146   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)A->data;
147   PetscInt       i,n,*garray = aij->garray;
148   Mat_SeqAIJ     *a_aij = (Mat_SeqAIJ*) aij->A->data;
149   Mat_SeqAIJ     *b_aij = (Mat_SeqAIJ*) aij->B->data;
150   PetscReal      *work;
151 
152   PetscFunctionBegin;
153   ierr = MatGetSize(A,NULL,&n);CHKERRQ(ierr);
154   ierr = PetscCalloc1(n,&work);CHKERRQ(ierr);
155   if (type == NORM_2) {
156     for (i=0; i<a_aij->i[aij->A->rmap->n]; i++) {
157       work[A->cmap->rstart + a_aij->j[i]] += PetscAbsScalar(a_aij->a[i]*a_aij->a[i]);
158     }
159     for (i=0; i<b_aij->i[aij->B->rmap->n]; i++) {
160       work[garray[b_aij->j[i]]] += PetscAbsScalar(b_aij->a[i]*b_aij->a[i]);
161     }
162   } else if (type == NORM_1) {
163     for (i=0; i<a_aij->i[aij->A->rmap->n]; i++) {
164       work[A->cmap->rstart + a_aij->j[i]] += PetscAbsScalar(a_aij->a[i]);
165     }
166     for (i=0; i<b_aij->i[aij->B->rmap->n]; i++) {
167       work[garray[b_aij->j[i]]] += PetscAbsScalar(b_aij->a[i]);
168     }
169   } else if (type == NORM_INFINITY) {
170     for (i=0; i<a_aij->i[aij->A->rmap->n]; i++) {
171       work[A->cmap->rstart + a_aij->j[i]] = PetscMax(PetscAbsScalar(a_aij->a[i]), work[A->cmap->rstart + a_aij->j[i]]);
172     }
173     for (i=0; i<b_aij->i[aij->B->rmap->n]; i++) {
174       work[garray[b_aij->j[i]]] = PetscMax(PetscAbsScalar(b_aij->a[i]),work[garray[b_aij->j[i]]]);
175     }
176 
177   } else SETERRQ(PetscObjectComm((PetscObject)A),PETSC_ERR_ARG_WRONG,"Unknown NormType");
178   if (type == NORM_INFINITY) {
179     ierr = MPI_Allreduce(work,norms,n,MPIU_REAL,MPIU_MAX,PetscObjectComm((PetscObject)A));CHKERRQ(ierr);
180   } else {
181     ierr = MPI_Allreduce(work,norms,n,MPIU_REAL,MPIU_SUM,PetscObjectComm((PetscObject)A));CHKERRQ(ierr);
182   }
183   ierr = PetscFree(work);CHKERRQ(ierr);
184   if (type == NORM_2) {
185     for (i=0; i<n; i++) norms[i] = PetscSqrtReal(norms[i]);
186   }
187   PetscFunctionReturn(0);
188 }
189 
190 #undef __FUNCT__
191 #define __FUNCT__ "MatDistribute_MPIAIJ"
192 /*
193     Distributes a SeqAIJ matrix across a set of processes. Code stolen from
194     MatLoad_MPIAIJ(). Horrible lack of reuse. Should be a routine for each matrix type.
195 
196     Only for square matrices
197 
198     Used by a preconditioner, hence PETSC_EXTERN
199 */
200 PETSC_EXTERN PetscErrorCode MatDistribute_MPIAIJ(MPI_Comm comm,Mat gmat,PetscInt m,MatReuse reuse,Mat *inmat)
201 {
202   PetscMPIInt    rank,size;
203   PetscInt       *rowners,*dlens,*olens,i,rstart,rend,j,jj,nz = 0,*gmataj,cnt,row,*ld,bses[2];
204   PetscErrorCode ierr;
205   Mat            mat;
206   Mat_SeqAIJ     *gmata;
207   PetscMPIInt    tag;
208   MPI_Status     status;
209   PetscBool      aij;
210   MatScalar      *gmataa,*ao,*ad,*gmataarestore=0;
211 
212   PetscFunctionBegin;
213   ierr = MPI_Comm_rank(comm,&rank);CHKERRQ(ierr);
214   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
215   if (!rank) {
216     ierr = PetscObjectTypeCompare((PetscObject)gmat,MATSEQAIJ,&aij);CHKERRQ(ierr);
217     if (!aij) SETERRQ1(PetscObjectComm((PetscObject)gmat),PETSC_ERR_SUP,"Currently no support for input matrix of type %s\n",((PetscObject)gmat)->type_name);
218   }
219   if (reuse == MAT_INITIAL_MATRIX) {
220     ierr = MatCreate(comm,&mat);CHKERRQ(ierr);
221     ierr = MatSetSizes(mat,m,m,PETSC_DETERMINE,PETSC_DETERMINE);CHKERRQ(ierr);
222     ierr = MatGetBlockSizes(gmat,&bses[0],&bses[1]);CHKERRQ(ierr);
223     ierr = MPI_Bcast(bses,2,MPIU_INT,0,comm);CHKERRQ(ierr);
224     ierr = MatSetBlockSizes(mat,bses[0],bses[1]);CHKERRQ(ierr);
225     ierr = MatSetType(mat,MATAIJ);CHKERRQ(ierr);
226     ierr = PetscMalloc1((size+1),&rowners);CHKERRQ(ierr);
227     ierr = PetscMalloc2(m,&dlens,m,&olens);CHKERRQ(ierr);
228     ierr = MPI_Allgather(&m,1,MPIU_INT,rowners+1,1,MPIU_INT,comm);CHKERRQ(ierr);
229 
230     rowners[0] = 0;
231     for (i=2; i<=size; i++) rowners[i] += rowners[i-1];
232     rstart = rowners[rank];
233     rend   = rowners[rank+1];
234     ierr   = PetscObjectGetNewTag((PetscObject)mat,&tag);CHKERRQ(ierr);
235     if (!rank) {
236       gmata = (Mat_SeqAIJ*) gmat->data;
237       /* send row lengths to all processors */
238       for (i=0; i<m; i++) dlens[i] = gmata->ilen[i];
239       for (i=1; i<size; i++) {
240         ierr = MPI_Send(gmata->ilen + rowners[i],rowners[i+1]-rowners[i],MPIU_INT,i,tag,comm);CHKERRQ(ierr);
241       }
242       /* determine number diagonal and off-diagonal counts */
243       ierr = PetscMemzero(olens,m*sizeof(PetscInt));CHKERRQ(ierr);
244       ierr = PetscCalloc1(m,&ld);CHKERRQ(ierr);
245       jj   = 0;
246       for (i=0; i<m; i++) {
247         for (j=0; j<dlens[i]; j++) {
248           if (gmata->j[jj] < rstart) ld[i]++;
249           if (gmata->j[jj] < rstart || gmata->j[jj] >= rend) olens[i]++;
250           jj++;
251         }
252       }
253       /* send column indices to other processes */
254       for (i=1; i<size; i++) {
255         nz   = gmata->i[rowners[i+1]]-gmata->i[rowners[i]];
256         ierr = MPI_Send(&nz,1,MPIU_INT,i,tag,comm);CHKERRQ(ierr);
257         ierr = MPI_Send(gmata->j + gmata->i[rowners[i]],nz,MPIU_INT,i,tag,comm);CHKERRQ(ierr);
258       }
259 
260       /* send numerical values to other processes */
261       for (i=1; i<size; i++) {
262         nz   = gmata->i[rowners[i+1]]-gmata->i[rowners[i]];
263         ierr = MPI_Send(gmata->a + gmata->i[rowners[i]],nz,MPIU_SCALAR,i,tag,comm);CHKERRQ(ierr);
264       }
265       gmataa = gmata->a;
266       gmataj = gmata->j;
267 
268     } else {
269       /* receive row lengths */
270       ierr = MPI_Recv(dlens,m,MPIU_INT,0,tag,comm,&status);CHKERRQ(ierr);
271       /* receive column indices */
272       ierr = MPI_Recv(&nz,1,MPIU_INT,0,tag,comm,&status);CHKERRQ(ierr);
273       ierr = PetscMalloc2(nz,&gmataa,nz,&gmataj);CHKERRQ(ierr);
274       ierr = MPI_Recv(gmataj,nz,MPIU_INT,0,tag,comm,&status);CHKERRQ(ierr);
275       /* determine number diagonal and off-diagonal counts */
276       ierr = PetscMemzero(olens,m*sizeof(PetscInt));CHKERRQ(ierr);
277       ierr = PetscCalloc1(m,&ld);CHKERRQ(ierr);
278       jj   = 0;
279       for (i=0; i<m; i++) {
280         for (j=0; j<dlens[i]; j++) {
281           if (gmataj[jj] < rstart) ld[i]++;
282           if (gmataj[jj] < rstart || gmataj[jj] >= rend) olens[i]++;
283           jj++;
284         }
285       }
286       /* receive numerical values */
287       ierr = PetscMemzero(gmataa,nz*sizeof(PetscScalar));CHKERRQ(ierr);
288       ierr = MPI_Recv(gmataa,nz,MPIU_SCALAR,0,tag,comm,&status);CHKERRQ(ierr);
289     }
290     /* set preallocation */
291     for (i=0; i<m; i++) {
292       dlens[i] -= olens[i];
293     }
294     ierr = MatSeqAIJSetPreallocation(mat,0,dlens);CHKERRQ(ierr);
295     ierr = MatMPIAIJSetPreallocation(mat,0,dlens,0,olens);CHKERRQ(ierr);
296 
297     for (i=0; i<m; i++) {
298       dlens[i] += olens[i];
299     }
300     cnt = 0;
301     for (i=0; i<m; i++) {
302       row  = rstart + i;
303       ierr = MatSetValues(mat,1,&row,dlens[i],gmataj+cnt,gmataa+cnt,INSERT_VALUES);CHKERRQ(ierr);
304       cnt += dlens[i];
305     }
306     if (rank) {
307       ierr = PetscFree2(gmataa,gmataj);CHKERRQ(ierr);
308     }
309     ierr = PetscFree2(dlens,olens);CHKERRQ(ierr);
310     ierr = PetscFree(rowners);CHKERRQ(ierr);
311 
312     ((Mat_MPIAIJ*)(mat->data))->ld = ld;
313 
314     *inmat = mat;
315   } else {   /* column indices are already set; only need to move over numerical values from process 0 */
316     Mat_SeqAIJ *Ad = (Mat_SeqAIJ*)((Mat_MPIAIJ*)((*inmat)->data))->A->data;
317     Mat_SeqAIJ *Ao = (Mat_SeqAIJ*)((Mat_MPIAIJ*)((*inmat)->data))->B->data;
318     mat  = *inmat;
319     ierr = PetscObjectGetNewTag((PetscObject)mat,&tag);CHKERRQ(ierr);
320     if (!rank) {
321       /* send numerical values to other processes */
322       gmata  = (Mat_SeqAIJ*) gmat->data;
323       ierr   = MatGetOwnershipRanges(mat,(const PetscInt**)&rowners);CHKERRQ(ierr);
324       gmataa = gmata->a;
325       for (i=1; i<size; i++) {
326         nz   = gmata->i[rowners[i+1]]-gmata->i[rowners[i]];
327         ierr = MPI_Send(gmataa + gmata->i[rowners[i]],nz,MPIU_SCALAR,i,tag,comm);CHKERRQ(ierr);
328       }
329       nz = gmata->i[rowners[1]]-gmata->i[rowners[0]];
330     } else {
331       /* receive numerical values from process 0*/
332       nz   = Ad->nz + Ao->nz;
333       ierr = PetscMalloc1(nz,&gmataa);CHKERRQ(ierr); gmataarestore = gmataa;
334       ierr = MPI_Recv(gmataa,nz,MPIU_SCALAR,0,tag,comm,&status);CHKERRQ(ierr);
335     }
336     /* transfer numerical values into the diagonal A and off diagonal B parts of mat */
337     ld = ((Mat_MPIAIJ*)(mat->data))->ld;
338     ad = Ad->a;
339     ao = Ao->a;
340     if (mat->rmap->n) {
341       i  = 0;
342       nz = ld[i];                                   ierr = PetscMemcpy(ao,gmataa,nz*sizeof(PetscScalar));CHKERRQ(ierr); ao += nz; gmataa += nz;
343       nz = Ad->i[i+1] - Ad->i[i];                   ierr = PetscMemcpy(ad,gmataa,nz*sizeof(PetscScalar));CHKERRQ(ierr); ad += nz; gmataa += nz;
344     }
345     for (i=1; i<mat->rmap->n; i++) {
346       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;
347       nz = Ad->i[i+1] - Ad->i[i];                   ierr = PetscMemcpy(ad,gmataa,nz*sizeof(PetscScalar));CHKERRQ(ierr); ad += nz; gmataa += nz;
348     }
349     i--;
350     if (mat->rmap->n) {
351       nz = Ao->i[i+1] - Ao->i[i] - ld[i];           ierr = PetscMemcpy(ao,gmataa,nz*sizeof(PetscScalar));CHKERRQ(ierr);
352     }
353     if (rank) {
354       ierr = PetscFree(gmataarestore);CHKERRQ(ierr);
355     }
356   }
357   ierr = MatAssemblyBegin(mat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
358   ierr = MatAssemblyEnd(mat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
359   PetscFunctionReturn(0);
360 }
361 
362 /*
363   Local utility routine that creates a mapping from the global column
364 number to the local number in the off-diagonal part of the local
365 storage of the matrix.  When PETSC_USE_CTABLE is used this is scalable at
366 a slightly higher hash table cost; without it it is not scalable (each processor
367 has an order N integer array but is fast to acess.
368 */
369 #undef __FUNCT__
370 #define __FUNCT__ "MatCreateColmap_MPIAIJ_Private"
371 PetscErrorCode MatCreateColmap_MPIAIJ_Private(Mat mat)
372 {
373   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
374   PetscErrorCode ierr;
375   PetscInt       n = aij->B->cmap->n,i;
376 
377   PetscFunctionBegin;
378   if (!aij->garray) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_PLIB,"MPIAIJ Matrix was assembled but is missing garray");
379 #if defined(PETSC_USE_CTABLE)
380   ierr = PetscTableCreate(n,mat->cmap->N+1,&aij->colmap);CHKERRQ(ierr);
381   for (i=0; i<n; i++) {
382     ierr = PetscTableAdd(aij->colmap,aij->garray[i]+1,i+1,INSERT_VALUES);CHKERRQ(ierr);
383   }
384 #else
385   ierr = PetscCalloc1((mat->cmap->N+1),&aij->colmap);CHKERRQ(ierr);
386   ierr = PetscLogObjectMemory((PetscObject)mat,(mat->cmap->N+1)*sizeof(PetscInt));CHKERRQ(ierr);
387   for (i=0; i<n; i++) aij->colmap[aij->garray[i]] = i+1;
388 #endif
389   PetscFunctionReturn(0);
390 }
391 
392 #define MatSetValues_SeqAIJ_A_Private(row,col,value,addv) \
393 { \
394     if (col <= lastcol1)  low1 = 0;     \
395     else                 high1 = nrow1; \
396     lastcol1 = col;\
397     while (high1-low1 > 5) { \
398       t = (low1+high1)/2; \
399       if (rp1[t] > col) high1 = t; \
400       else              low1  = t; \
401     } \
402       for (_i=low1; _i<high1; _i++) { \
403         if (rp1[_i] > col) break; \
404         if (rp1[_i] == col) { \
405           if (addv == ADD_VALUES) ap1[_i] += value;   \
406           else                    ap1[_i] = value; \
407           goto a_noinsert; \
408         } \
409       }  \
410       if (value == 0.0 && ignorezeroentries) {low1 = 0; high1 = nrow1;goto a_noinsert;} \
411       if (nonew == 1) {low1 = 0; high1 = nrow1; goto a_noinsert;}                \
412       if (nonew == -1) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Inserting a new nonzero (%D, %D) into matrix", row, col); \
413       MatSeqXAIJReallocateAIJ(A,am,1,nrow1,row,col,rmax1,aa,ai,aj,rp1,ap1,aimax,nonew,MatScalar); \
414       N = nrow1++ - 1; a->nz++; high1++; \
415       /* shift up all the later entries in this row */ \
416       for (ii=N; ii>=_i; ii--) { \
417         rp1[ii+1] = rp1[ii]; \
418         ap1[ii+1] = ap1[ii]; \
419       } \
420       rp1[_i] = col;  \
421       ap1[_i] = value;  \
422       A->nonzerostate++;\
423       a_noinsert: ; \
424       ailen[row] = nrow1; \
425 }
426 
427 
428 #define MatSetValues_SeqAIJ_B_Private(row,col,value,addv) \
429   { \
430     if (col <= lastcol2) low2 = 0;                        \
431     else high2 = nrow2;                                   \
432     lastcol2 = col;                                       \
433     while (high2-low2 > 5) {                              \
434       t = (low2+high2)/2;                                 \
435       if (rp2[t] > col) high2 = t;                        \
436       else             low2  = t;                         \
437     }                                                     \
438     for (_i=low2; _i<high2; _i++) {                       \
439       if (rp2[_i] > col) break;                           \
440       if (rp2[_i] == col) {                               \
441         if (addv == ADD_VALUES) ap2[_i] += value;         \
442         else                    ap2[_i] = value;          \
443         goto b_noinsert;                                  \
444       }                                                   \
445     }                                                     \
446     if (value == 0.0 && ignorezeroentries) {low2 = 0; high2 = nrow2; goto b_noinsert;} \
447     if (nonew == 1) {low2 = 0; high2 = nrow2; goto b_noinsert;}                        \
448     if (nonew == -1) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Inserting a new nonzero (%D, %D) into matrix", row, col); \
449     MatSeqXAIJReallocateAIJ(B,bm,1,nrow2,row,col,rmax2,ba,bi,bj,rp2,ap2,bimax,nonew,MatScalar); \
450     N = nrow2++ - 1; b->nz++; high2++;                    \
451     /* shift up all the later entries in this row */      \
452     for (ii=N; ii>=_i; ii--) {                            \
453       rp2[ii+1] = rp2[ii];                                \
454       ap2[ii+1] = ap2[ii];                                \
455     }                                                     \
456     rp2[_i] = col;                                        \
457     ap2[_i] = value;                                      \
458     B->nonzerostate++;                                    \
459     b_noinsert: ;                                         \
460     bilen[row] = nrow2;                                   \
461   }
462 
463 #undef __FUNCT__
464 #define __FUNCT__ "MatSetValuesRow_MPIAIJ"
465 PetscErrorCode MatSetValuesRow_MPIAIJ(Mat A,PetscInt row,const PetscScalar v[])
466 {
467   Mat_MPIAIJ     *mat = (Mat_MPIAIJ*)A->data;
468   Mat_SeqAIJ     *a   = (Mat_SeqAIJ*)mat->A->data,*b = (Mat_SeqAIJ*)mat->B->data;
469   PetscErrorCode ierr;
470   PetscInt       l,*garray = mat->garray,diag;
471 
472   PetscFunctionBegin;
473   /* code only works for square matrices A */
474 
475   /* find size of row to the left of the diagonal part */
476   ierr = MatGetOwnershipRange(A,&diag,0);CHKERRQ(ierr);
477   row  = row - diag;
478   for (l=0; l<b->i[row+1]-b->i[row]; l++) {
479     if (garray[b->j[b->i[row]+l]] > diag) break;
480   }
481   ierr = PetscMemcpy(b->a+b->i[row],v,l*sizeof(PetscScalar));CHKERRQ(ierr);
482 
483   /* diagonal part */
484   ierr = PetscMemcpy(a->a+a->i[row],v+l,(a->i[row+1]-a->i[row])*sizeof(PetscScalar));CHKERRQ(ierr);
485 
486   /* right of diagonal part */
487   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);
488   PetscFunctionReturn(0);
489 }
490 
491 #undef __FUNCT__
492 #define __FUNCT__ "MatSetValues_MPIAIJ"
493 PetscErrorCode MatSetValues_MPIAIJ(Mat mat,PetscInt m,const PetscInt im[],PetscInt n,const PetscInt in[],const PetscScalar v[],InsertMode addv)
494 {
495   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
496   PetscScalar    value;
497   PetscErrorCode ierr;
498   PetscInt       i,j,rstart  = mat->rmap->rstart,rend = mat->rmap->rend;
499   PetscInt       cstart      = mat->cmap->rstart,cend = mat->cmap->rend,row,col;
500   PetscBool      roworiented = aij->roworiented;
501 
502   /* Some Variables required in the macro */
503   Mat        A                 = aij->A;
504   Mat_SeqAIJ *a                = (Mat_SeqAIJ*)A->data;
505   PetscInt   *aimax            = a->imax,*ai = a->i,*ailen = a->ilen,*aj = a->j;
506   MatScalar  *aa               = a->a;
507   PetscBool  ignorezeroentries = a->ignorezeroentries;
508   Mat        B                 = aij->B;
509   Mat_SeqAIJ *b                = (Mat_SeqAIJ*)B->data;
510   PetscInt   *bimax            = b->imax,*bi = b->i,*bilen = b->ilen,*bj = b->j,bm = aij->B->rmap->n,am = aij->A->rmap->n;
511   MatScalar  *ba               = b->a;
512 
513   PetscInt  *rp1,*rp2,ii,nrow1,nrow2,_i,rmax1,rmax2,N,low1,high1,low2,high2,t,lastcol1,lastcol2;
514   PetscInt  nonew;
515   MatScalar *ap1,*ap2;
516 
517   PetscFunctionBegin;
518   for (i=0; i<m; i++) {
519     if (im[i] < 0) continue;
520 #if defined(PETSC_USE_DEBUG)
521     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);
522 #endif
523     if (im[i] >= rstart && im[i] < rend) {
524       row      = im[i] - rstart;
525       lastcol1 = -1;
526       rp1      = aj + ai[row];
527       ap1      = aa + ai[row];
528       rmax1    = aimax[row];
529       nrow1    = ailen[row];
530       low1     = 0;
531       high1    = nrow1;
532       lastcol2 = -1;
533       rp2      = bj + bi[row];
534       ap2      = ba + bi[row];
535       rmax2    = bimax[row];
536       nrow2    = bilen[row];
537       low2     = 0;
538       high2    = nrow2;
539 
540       for (j=0; j<n; j++) {
541         if (roworiented) value = v[i*n+j];
542         else             value = v[i+j*m];
543         if (ignorezeroentries && value == 0.0 && (addv == ADD_VALUES)) continue;
544         if (in[j] >= cstart && in[j] < cend) {
545           col   = in[j] - cstart;
546           nonew = a->nonew;
547           MatSetValues_SeqAIJ_A_Private(row,col,value,addv);
548         } else if (in[j] < 0) continue;
549 #if defined(PETSC_USE_DEBUG)
550         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);
551 #endif
552         else {
553           if (mat->was_assembled) {
554             if (!aij->colmap) {
555               ierr = MatCreateColmap_MPIAIJ_Private(mat);CHKERRQ(ierr);
556             }
557 #if defined(PETSC_USE_CTABLE)
558             ierr = PetscTableFind(aij->colmap,in[j]+1,&col);CHKERRQ(ierr);
559             col--;
560 #else
561             col = aij->colmap[in[j]] - 1;
562 #endif
563             if (col < 0 && !((Mat_SeqAIJ*)(aij->B->data))->nonew) {
564               ierr = MatDisAssemble_MPIAIJ(mat);CHKERRQ(ierr);
565               col  =  in[j];
566               /* Reinitialize the variables required by MatSetValues_SeqAIJ_B_Private() */
567               B     = aij->B;
568               b     = (Mat_SeqAIJ*)B->data;
569               bimax = b->imax; bi = b->i; bilen = b->ilen; bj = b->j; ba = b->a;
570               rp2   = bj + bi[row];
571               ap2   = ba + bi[row];
572               rmax2 = bimax[row];
573               nrow2 = bilen[row];
574               low2  = 0;
575               high2 = nrow2;
576               bm    = aij->B->rmap->n;
577               ba    = b->a;
578             } else if (col < 0) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Inserting a new nonzero (%D, %D) into matrix", im[i], in[j]);
579           } else col = in[j];
580           nonew = b->nonew;
581           MatSetValues_SeqAIJ_B_Private(row,col,value,addv);
582         }
583       }
584     } else {
585       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]);
586       if (!aij->donotstash) {
587         mat->assembled = PETSC_FALSE;
588         if (roworiented) {
589           ierr = MatStashValuesRow_Private(&mat->stash,im[i],n,in,v+i*n,(PetscBool)(ignorezeroentries && (addv == ADD_VALUES)));CHKERRQ(ierr);
590         } else {
591           ierr = MatStashValuesCol_Private(&mat->stash,im[i],n,in,v+i,m,(PetscBool)(ignorezeroentries && (addv == ADD_VALUES)));CHKERRQ(ierr);
592         }
593       }
594     }
595   }
596   PetscFunctionReturn(0);
597 }
598 
599 #undef __FUNCT__
600 #define __FUNCT__ "MatGetValues_MPIAIJ"
601 PetscErrorCode MatGetValues_MPIAIJ(Mat mat,PetscInt m,const PetscInt idxm[],PetscInt n,const PetscInt idxn[],PetscScalar v[])
602 {
603   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
604   PetscErrorCode ierr;
605   PetscInt       i,j,rstart = mat->rmap->rstart,rend = mat->rmap->rend;
606   PetscInt       cstart = mat->cmap->rstart,cend = mat->cmap->rend,row,col;
607 
608   PetscFunctionBegin;
609   for (i=0; i<m; i++) {
610     if (idxm[i] < 0) continue; /* SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Negative row: %D",idxm[i]);*/
611     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);
612     if (idxm[i] >= rstart && idxm[i] < rend) {
613       row = idxm[i] - rstart;
614       for (j=0; j<n; j++) {
615         if (idxn[j] < 0) continue; /* SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Negative column: %D",idxn[j]); */
616         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);
617         if (idxn[j] >= cstart && idxn[j] < cend) {
618           col  = idxn[j] - cstart;
619           ierr = MatGetValues(aij->A,1,&row,1,&col,v+i*n+j);CHKERRQ(ierr);
620         } else {
621           if (!aij->colmap) {
622             ierr = MatCreateColmap_MPIAIJ_Private(mat);CHKERRQ(ierr);
623           }
624 #if defined(PETSC_USE_CTABLE)
625           ierr = PetscTableFind(aij->colmap,idxn[j]+1,&col);CHKERRQ(ierr);
626           col--;
627 #else
628           col = aij->colmap[idxn[j]] - 1;
629 #endif
630           if ((col < 0) || (aij->garray[col] != idxn[j])) *(v+i*n+j) = 0.0;
631           else {
632             ierr = MatGetValues(aij->B,1,&row,1,&col,v+i*n+j);CHKERRQ(ierr);
633           }
634         }
635       }
636     } else SETERRQ(PETSC_COMM_SELF,PETSC_ERR_SUP,"Only local values currently supported");
637   }
638   PetscFunctionReturn(0);
639 }
640 
641 extern PetscErrorCode MatMultDiagonalBlock_MPIAIJ(Mat,Vec,Vec);
642 
643 #undef __FUNCT__
644 #define __FUNCT__ "MatAssemblyBegin_MPIAIJ"
645 PetscErrorCode MatAssemblyBegin_MPIAIJ(Mat mat,MatAssemblyType mode)
646 {
647   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
648   PetscErrorCode ierr;
649   PetscInt       nstash,reallocs;
650   InsertMode     addv;
651 
652   PetscFunctionBegin;
653   if (aij->donotstash || mat->nooffprocentries) PetscFunctionReturn(0);
654 
655   /* make sure all processors are either in INSERTMODE or ADDMODE */
656   ierr = MPI_Allreduce((PetscEnum*)&mat->insertmode,(PetscEnum*)&addv,1,MPIU_ENUM,MPI_BOR,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
657   if (addv == (ADD_VALUES|INSERT_VALUES)) SETERRQ(PetscObjectComm((PetscObject)mat),PETSC_ERR_ARG_WRONGSTATE,"Some processors inserted others added");
658   mat->insertmode = addv; /* in case this processor had no cache */
659 
660   ierr = MatStashScatterBegin_Private(mat,&mat->stash,mat->rmap->range);CHKERRQ(ierr);
661   ierr = MatStashGetInfo_Private(&mat->stash,&nstash,&reallocs);CHKERRQ(ierr);
662   ierr = PetscInfo2(aij->A,"Stash has %D entries, uses %D mallocs.\n",nstash,reallocs);CHKERRQ(ierr);
663   PetscFunctionReturn(0);
664 }
665 
666 #undef __FUNCT__
667 #define __FUNCT__ "MatAssemblyEnd_MPIAIJ"
668 PetscErrorCode MatAssemblyEnd_MPIAIJ(Mat mat,MatAssemblyType mode)
669 {
670   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
671   Mat_SeqAIJ     *a   = (Mat_SeqAIJ*)aij->A->data;
672   PetscErrorCode ierr;
673   PetscMPIInt    n;
674   PetscInt       i,j,rstart,ncols,flg;
675   PetscInt       *row,*col;
676   PetscBool      other_disassembled;
677   PetscScalar    *val;
678   InsertMode     addv = mat->insertmode;
679 
680   /* do not use 'b = (Mat_SeqAIJ*)aij->B->data' as B can be reset in disassembly */
681 
682   PetscFunctionBegin;
683   if (!aij->donotstash && !mat->nooffprocentries) {
684     while (1) {
685       ierr = MatStashScatterGetMesg_Private(&mat->stash,&n,&row,&col,&val,&flg);CHKERRQ(ierr);
686       if (!flg) break;
687 
688       for (i=0; i<n; ) {
689         /* Now identify the consecutive vals belonging to the same row */
690         for (j=i,rstart=row[j]; j<n; j++) {
691           if (row[j] != rstart) break;
692         }
693         if (j < n) ncols = j-i;
694         else       ncols = n-i;
695         /* Now assemble all these values with a single function call */
696         ierr = MatSetValues_MPIAIJ(mat,1,row+i,ncols,col+i,val+i,addv);CHKERRQ(ierr);
697 
698         i = j;
699       }
700     }
701     ierr = MatStashScatterEnd_Private(&mat->stash);CHKERRQ(ierr);
702   }
703   ierr = MatAssemblyBegin(aij->A,mode);CHKERRQ(ierr);
704   ierr = MatAssemblyEnd(aij->A,mode);CHKERRQ(ierr);
705 
706   /* determine if any processor has disassembled, if so we must
707      also disassemble ourselfs, in order that we may reassemble. */
708   /*
709      if nonzero structure of submatrix B cannot change then we know that
710      no processor disassembled thus we can skip this stuff
711   */
712   if (!((Mat_SeqAIJ*)aij->B->data)->nonew) {
713     ierr = MPI_Allreduce(&mat->was_assembled,&other_disassembled,1,MPIU_BOOL,MPI_PROD,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
714     if (mat->was_assembled && !other_disassembled) {
715       ierr = MatDisAssemble_MPIAIJ(mat);CHKERRQ(ierr);
716     }
717   }
718   if (!mat->was_assembled && mode == MAT_FINAL_ASSEMBLY) {
719     ierr = MatSetUpMultiply_MPIAIJ(mat);CHKERRQ(ierr);
720   }
721   ierr = MatSetOption(aij->B,MAT_USE_INODES,PETSC_FALSE);CHKERRQ(ierr);
722   ierr = MatAssemblyBegin(aij->B,mode);CHKERRQ(ierr);
723   ierr = MatAssemblyEnd(aij->B,mode);CHKERRQ(ierr);
724 
725   ierr = PetscFree2(aij->rowvalues,aij->rowindices);CHKERRQ(ierr);
726 
727   aij->rowvalues = 0;
728 
729   /* used by MatAXPY() */
730   a->xtoy = 0; ((Mat_SeqAIJ*)aij->B->data)->xtoy = 0;   /* b->xtoy = 0 */
731   a->XtoY = 0; ((Mat_SeqAIJ*)aij->B->data)->XtoY = 0;   /* b->XtoY = 0 */
732 
733   ierr = VecDestroy(&aij->diag);CHKERRQ(ierr);
734   if (a->inode.size) mat->ops->multdiagonalblock = MatMultDiagonalBlock_MPIAIJ;
735 
736   /* if no new nonzero locations are allowed in matrix then only set the matrix state the first time through */
737   if ((!mat->was_assembled && mode == MAT_FINAL_ASSEMBLY) || !((Mat_SeqAIJ*)(aij->A->data))->nonew) {
738     PetscObjectState state = aij->A->nonzerostate + aij->B->nonzerostate;
739     ierr = MPI_Allreduce(&state,&mat->nonzerostate,1,MPIU_INT64,MPI_SUM,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
740   }
741   PetscFunctionReturn(0);
742 }
743 
744 #undef __FUNCT__
745 #define __FUNCT__ "MatZeroEntries_MPIAIJ"
746 PetscErrorCode MatZeroEntries_MPIAIJ(Mat A)
747 {
748   Mat_MPIAIJ     *l = (Mat_MPIAIJ*)A->data;
749   PetscErrorCode ierr;
750 
751   PetscFunctionBegin;
752   ierr = MatZeroEntries(l->A);CHKERRQ(ierr);
753   ierr = MatZeroEntries(l->B);CHKERRQ(ierr);
754   PetscFunctionReturn(0);
755 }
756 
757 #undef __FUNCT__
758 #define __FUNCT__ "MatZeroRows_MPIAIJ"
759 PetscErrorCode MatZeroRows_MPIAIJ(Mat A,PetscInt N,const PetscInt rows[],PetscScalar diag,Vec x,Vec b)
760 {
761   Mat_MPIAIJ    *mat    = (Mat_MPIAIJ *) A->data;
762   PetscInt      *owners = A->rmap->range;
763   PetscInt       n      = A->rmap->n;
764   PetscSF        sf;
765   PetscInt      *lrows;
766   PetscSFNode   *rrows;
767   PetscInt       r, p = 0, len = 0;
768   PetscErrorCode ierr;
769 
770   PetscFunctionBegin;
771   /* Create SF where leaves are input rows and roots are owned rows */
772   ierr = PetscMalloc1(n, &lrows);CHKERRQ(ierr);
773   for (r = 0; r < n; ++r) lrows[r] = -1;
774   if (!A->nooffproczerorows) {ierr = PetscMalloc1(N, &rrows);CHKERRQ(ierr);}
775   for (r = 0; r < N; ++r) {
776     const PetscInt idx   = rows[r];
777     if (idx < 0 || A->rmap->N <= idx) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Row %D out of range [0,%D)",idx,A->rmap->N);
778     if (idx < owners[p] || owners[p+1] <= idx) { /* short-circuit the search if the last p owns this row too */
779       ierr = PetscLayoutFindOwner(A->rmap,idx,&p);CHKERRQ(ierr);
780     }
781     if (A->nooffproczerorows) {
782       if (p != mat->rank) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"MAT_NO_OFF_PROC_ZERO_ROWS set, but row %D is not owned by rank %d",idx,mat->rank);
783       lrows[len++] = idx - owners[p];
784     } else {
785       rrows[r].rank = p;
786       rrows[r].index = rows[r] - owners[p];
787     }
788   }
789   if (!A->nooffproczerorows) {
790     ierr = PetscSFCreate(PetscObjectComm((PetscObject) A), &sf);CHKERRQ(ierr);
791     ierr = PetscSFSetGraph(sf, n, N, NULL, PETSC_OWN_POINTER, rrows, PETSC_OWN_POINTER);CHKERRQ(ierr);
792     /* Collect flags for rows to be zeroed */
793     ierr = PetscSFReduceBegin(sf, MPIU_INT, (PetscInt*)rows, lrows, MPI_LOR);CHKERRQ(ierr);
794     ierr = PetscSFReduceEnd(sf, MPIU_INT, (PetscInt*)rows, lrows, MPI_LOR);CHKERRQ(ierr);
795     ierr = PetscSFDestroy(&sf);CHKERRQ(ierr);
796     /* Compress and put in row numbers */
797     for (r = 0; r < n; ++r) if (lrows[r] >= 0) lrows[len++] = r;
798   }
799   /* fix right hand side if needed */
800   if (x && b) {
801     const PetscScalar *xx;
802     PetscScalar       *bb;
803 
804     ierr = VecGetArrayRead(x, &xx);CHKERRQ(ierr);
805     ierr = VecGetArray(b, &bb);CHKERRQ(ierr);
806     for (r = 0; r < len; ++r) bb[lrows[r]] = diag*xx[lrows[r]];
807     ierr = VecRestoreArrayRead(x, &xx);CHKERRQ(ierr);
808     ierr = VecRestoreArray(b, &bb);CHKERRQ(ierr);
809   }
810   /* Must zero l->B before l->A because the (diag) case below may put values into l->B*/
811   ierr = MatZeroRows(mat->B, len, lrows, 0.0, NULL, NULL);CHKERRQ(ierr);
812   if ((diag != 0.0) && (mat->A->rmap->N == mat->A->cmap->N)) {
813     ierr = MatZeroRows(mat->A, len, lrows, diag, NULL, NULL);CHKERRQ(ierr);
814   } else if (diag != 0.0) {
815     ierr = MatZeroRows(mat->A, len, lrows, 0.0, NULL, NULL);CHKERRQ(ierr);
816     if (((Mat_SeqAIJ *) mat->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");
817     for (r = 0; r < len; ++r) {
818       const PetscInt row = lrows[r] + A->rmap->rstart;
819       ierr = MatSetValues(A, 1, &row, 1, &row, &diag, INSERT_VALUES);CHKERRQ(ierr);
820     }
821     ierr = MatAssemblyBegin(A, MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
822     ierr = MatAssemblyEnd(A, MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
823   } else {
824     ierr = MatZeroRows(mat->A, len, lrows, 0.0, NULL, NULL);CHKERRQ(ierr);
825   }
826   ierr = PetscFree(lrows);CHKERRQ(ierr);
827 
828   /* only change matrix nonzero state if pattern was allowed to be changed */
829   if (!((Mat_SeqAIJ*)(mat->A->data))->keepnonzeropattern) {
830     PetscObjectState state = mat->A->nonzerostate + mat->B->nonzerostate;
831     ierr = MPI_Allreduce(&state,&A->nonzerostate,1,MPIU_INT64,MPI_SUM,PetscObjectComm((PetscObject)A));CHKERRQ(ierr);
832   }
833   PetscFunctionReturn(0);
834 }
835 
836 #undef __FUNCT__
837 #define __FUNCT__ "MatZeroRowsColumns_MPIAIJ"
838 PetscErrorCode MatZeroRowsColumns_MPIAIJ(Mat A,PetscInt N,const PetscInt rows[],PetscScalar diag,Vec x,Vec b)
839 {
840   Mat_MPIAIJ        *l = (Mat_MPIAIJ*)A->data;
841   PetscErrorCode    ierr;
842   PetscMPIInt       n = A->rmap->n;
843   PetscInt          i,j,r,m,p = 0,len = 0;
844   PetscInt          *lrows,*owners = A->rmap->range;
845   PetscSFNode       *rrows;
846   PetscSF           sf;
847   const PetscScalar *xx;
848   PetscScalar       *bb,*mask;
849   Vec               xmask,lmask;
850   Mat_SeqAIJ        *aij = (Mat_SeqAIJ*)l->B->data;
851   const PetscInt    *aj, *ii,*ridx;
852   PetscScalar       *aa;
853 
854   PetscFunctionBegin;
855   /* Create SF where leaves are input rows and roots are owned rows */
856   ierr = PetscMalloc1(n, &lrows);CHKERRQ(ierr);
857   for (r = 0; r < n; ++r) lrows[r] = -1;
858   ierr = PetscMalloc1(N, &rrows);CHKERRQ(ierr);
859   for (r = 0; r < N; ++r) {
860     const PetscInt idx   = rows[r];
861     if (idx < 0 || A->rmap->N <= idx) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Row %D out of range [0,%D)",idx,A->rmap->N);
862     if (idx < owners[p] || owners[p+1] <= idx) { /* short-circuit the search if the last p owns this row too */
863       ierr = PetscLayoutFindOwner(A->rmap,idx,&p);CHKERRQ(ierr);
864     }
865     rrows[r].rank  = p;
866     rrows[r].index = rows[r] - owners[p];
867   }
868   ierr = PetscSFCreate(PetscObjectComm((PetscObject) A), &sf);CHKERRQ(ierr);
869   ierr = PetscSFSetGraph(sf, n, N, NULL, PETSC_OWN_POINTER, rrows, PETSC_OWN_POINTER);CHKERRQ(ierr);
870   /* Collect flags for rows to be zeroed */
871   ierr = PetscSFReduceBegin(sf, MPIU_INT, (PetscInt *) rows, lrows, MPI_LOR);CHKERRQ(ierr);
872   ierr = PetscSFReduceEnd(sf, MPIU_INT, (PetscInt *) rows, lrows, MPI_LOR);CHKERRQ(ierr);
873   ierr = PetscSFDestroy(&sf);CHKERRQ(ierr);
874   /* Compress and put in row numbers */
875   for (r = 0; r < n; ++r) if (lrows[r] >= 0) lrows[len++] = r;
876   /* zero diagonal part of matrix */
877   ierr = MatZeroRowsColumns(l->A,len,lrows,diag,x,b);CHKERRQ(ierr);
878   /* handle off diagonal part of matrix */
879   ierr = MatCreateVecs(A,&xmask,NULL);CHKERRQ(ierr);
880   ierr = VecDuplicate(l->lvec,&lmask);CHKERRQ(ierr);
881   ierr = VecGetArray(xmask,&bb);CHKERRQ(ierr);
882   for (i=0; i<len; i++) bb[lrows[i]] = 1;
883   ierr = VecRestoreArray(xmask,&bb);CHKERRQ(ierr);
884   ierr = VecScatterBegin(l->Mvctx,xmask,lmask,ADD_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
885   ierr = VecScatterEnd(l->Mvctx,xmask,lmask,ADD_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
886   ierr = VecDestroy(&xmask);CHKERRQ(ierr);
887   if (x) {
888     ierr = VecScatterBegin(l->Mvctx,x,l->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
889     ierr = VecScatterEnd(l->Mvctx,x,l->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
890     ierr = VecGetArrayRead(l->lvec,&xx);CHKERRQ(ierr);
891     ierr = VecGetArray(b,&bb);CHKERRQ(ierr);
892   }
893   ierr = VecGetArray(lmask,&mask);CHKERRQ(ierr);
894   /* remove zeroed rows of off diagonal matrix */
895   ii = aij->i;
896   for (i=0; i<len; i++) {
897     ierr = PetscMemzero(aij->a + ii[lrows[i]],(ii[lrows[i]+1] - ii[lrows[i]])*sizeof(PetscScalar));CHKERRQ(ierr);
898   }
899   /* loop over all elements of off process part of matrix zeroing removed columns*/
900   if (aij->compressedrow.use) {
901     m    = aij->compressedrow.nrows;
902     ii   = aij->compressedrow.i;
903     ridx = aij->compressedrow.rindex;
904     for (i=0; i<m; i++) {
905       n  = ii[i+1] - ii[i];
906       aj = aij->j + ii[i];
907       aa = aij->a + ii[i];
908 
909       for (j=0; j<n; j++) {
910         if (PetscAbsScalar(mask[*aj])) {
911           if (b) bb[*ridx] -= *aa*xx[*aj];
912           *aa = 0.0;
913         }
914         aa++;
915         aj++;
916       }
917       ridx++;
918     }
919   } else { /* do not use compressed row format */
920     m = l->B->rmap->n;
921     for (i=0; i<m; i++) {
922       n  = ii[i+1] - ii[i];
923       aj = aij->j + ii[i];
924       aa = aij->a + ii[i];
925       for (j=0; j<n; j++) {
926         if (PetscAbsScalar(mask[*aj])) {
927           if (b) bb[i] -= *aa*xx[*aj];
928           *aa = 0.0;
929         }
930         aa++;
931         aj++;
932       }
933     }
934   }
935   if (x) {
936     ierr = VecRestoreArray(b,&bb);CHKERRQ(ierr);
937     ierr = VecRestoreArrayRead(l->lvec,&xx);CHKERRQ(ierr);
938   }
939   ierr = VecRestoreArray(lmask,&mask);CHKERRQ(ierr);
940   ierr = VecDestroy(&lmask);CHKERRQ(ierr);
941   ierr = PetscFree(lrows);CHKERRQ(ierr);
942 
943   /* only change matrix nonzero state if pattern was allowed to be changed */
944   if (!((Mat_SeqAIJ*)(l->A->data))->keepnonzeropattern) {
945     PetscObjectState state = l->A->nonzerostate + l->B->nonzerostate;
946     ierr = MPI_Allreduce(&state,&A->nonzerostate,1,MPIU_INT64,MPI_SUM,PetscObjectComm((PetscObject)A));CHKERRQ(ierr);
947   }
948   PetscFunctionReturn(0);
949 }
950 
951 #undef __FUNCT__
952 #define __FUNCT__ "MatMult_MPIAIJ"
953 PetscErrorCode MatMult_MPIAIJ(Mat A,Vec xx,Vec yy)
954 {
955   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
956   PetscErrorCode ierr;
957   PetscInt       nt;
958 
959   PetscFunctionBegin;
960   ierr = VecGetLocalSize(xx,&nt);CHKERRQ(ierr);
961   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);
962   ierr = VecScatterBegin(a->Mvctx,xx,a->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
963   ierr = (*a->A->ops->mult)(a->A,xx,yy);CHKERRQ(ierr);
964   ierr = VecScatterEnd(a->Mvctx,xx,a->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
965   ierr = (*a->B->ops->multadd)(a->B,a->lvec,yy,yy);CHKERRQ(ierr);
966   PetscFunctionReturn(0);
967 }
968 
969 #undef __FUNCT__
970 #define __FUNCT__ "MatMultDiagonalBlock_MPIAIJ"
971 PetscErrorCode MatMultDiagonalBlock_MPIAIJ(Mat A,Vec bb,Vec xx)
972 {
973   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
974   PetscErrorCode ierr;
975 
976   PetscFunctionBegin;
977   ierr = MatMultDiagonalBlock(a->A,bb,xx);CHKERRQ(ierr);
978   PetscFunctionReturn(0);
979 }
980 
981 #undef __FUNCT__
982 #define __FUNCT__ "MatMultAdd_MPIAIJ"
983 PetscErrorCode MatMultAdd_MPIAIJ(Mat A,Vec xx,Vec yy,Vec zz)
984 {
985   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
986   PetscErrorCode ierr;
987 
988   PetscFunctionBegin;
989   ierr = VecScatterBegin(a->Mvctx,xx,a->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
990   ierr = (*a->A->ops->multadd)(a->A,xx,yy,zz);CHKERRQ(ierr);
991   ierr = VecScatterEnd(a->Mvctx,xx,a->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
992   ierr = (*a->B->ops->multadd)(a->B,a->lvec,zz,zz);CHKERRQ(ierr);
993   PetscFunctionReturn(0);
994 }
995 
996 #undef __FUNCT__
997 #define __FUNCT__ "MatMultTranspose_MPIAIJ"
998 PetscErrorCode MatMultTranspose_MPIAIJ(Mat A,Vec xx,Vec yy)
999 {
1000   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
1001   PetscErrorCode ierr;
1002   PetscBool      merged;
1003 
1004   PetscFunctionBegin;
1005   ierr = VecScatterGetMerged(a->Mvctx,&merged);CHKERRQ(ierr);
1006   /* do nondiagonal part */
1007   ierr = (*a->B->ops->multtranspose)(a->B,xx,a->lvec);CHKERRQ(ierr);
1008   if (!merged) {
1009     /* send it on its way */
1010     ierr = VecScatterBegin(a->Mvctx,a->lvec,yy,ADD_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
1011     /* do local part */
1012     ierr = (*a->A->ops->multtranspose)(a->A,xx,yy);CHKERRQ(ierr);
1013     /* receive remote parts: note this assumes the values are not actually */
1014     /* added in yy until the next line, */
1015     ierr = VecScatterEnd(a->Mvctx,a->lvec,yy,ADD_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
1016   } else {
1017     /* do local part */
1018     ierr = (*a->A->ops->multtranspose)(a->A,xx,yy);CHKERRQ(ierr);
1019     /* send it on its way */
1020     ierr = VecScatterBegin(a->Mvctx,a->lvec,yy,ADD_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
1021     /* values actually were received in the Begin() but we need to call this nop */
1022     ierr = VecScatterEnd(a->Mvctx,a->lvec,yy,ADD_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
1023   }
1024   PetscFunctionReturn(0);
1025 }
1026 
1027 #undef __FUNCT__
1028 #define __FUNCT__ "MatIsTranspose_MPIAIJ"
1029 PetscErrorCode  MatIsTranspose_MPIAIJ(Mat Amat,Mat Bmat,PetscReal tol,PetscBool  *f)
1030 {
1031   MPI_Comm       comm;
1032   Mat_MPIAIJ     *Aij = (Mat_MPIAIJ*) Amat->data, *Bij;
1033   Mat            Adia = Aij->A, Bdia, Aoff,Boff,*Aoffs,*Boffs;
1034   IS             Me,Notme;
1035   PetscErrorCode ierr;
1036   PetscInt       M,N,first,last,*notme,i;
1037   PetscMPIInt    size;
1038 
1039   PetscFunctionBegin;
1040   /* Easy test: symmetric diagonal block */
1041   Bij  = (Mat_MPIAIJ*) Bmat->data; Bdia = Bij->A;
1042   ierr = MatIsTranspose(Adia,Bdia,tol,f);CHKERRQ(ierr);
1043   if (!*f) PetscFunctionReturn(0);
1044   ierr = PetscObjectGetComm((PetscObject)Amat,&comm);CHKERRQ(ierr);
1045   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
1046   if (size == 1) PetscFunctionReturn(0);
1047 
1048   /* Hard test: off-diagonal block. This takes a MatGetSubMatrix. */
1049   ierr = MatGetSize(Amat,&M,&N);CHKERRQ(ierr);
1050   ierr = MatGetOwnershipRange(Amat,&first,&last);CHKERRQ(ierr);
1051   ierr = PetscMalloc1((N-last+first),&notme);CHKERRQ(ierr);
1052   for (i=0; i<first; i++) notme[i] = i;
1053   for (i=last; i<M; i++) notme[i-last+first] = i;
1054   ierr = ISCreateGeneral(MPI_COMM_SELF,N-last+first,notme,PETSC_COPY_VALUES,&Notme);CHKERRQ(ierr);
1055   ierr = ISCreateStride(MPI_COMM_SELF,last-first,first,1,&Me);CHKERRQ(ierr);
1056   ierr = MatGetSubMatrices(Amat,1,&Me,&Notme,MAT_INITIAL_MATRIX,&Aoffs);CHKERRQ(ierr);
1057   Aoff = Aoffs[0];
1058   ierr = MatGetSubMatrices(Bmat,1,&Notme,&Me,MAT_INITIAL_MATRIX,&Boffs);CHKERRQ(ierr);
1059   Boff = Boffs[0];
1060   ierr = MatIsTranspose(Aoff,Boff,tol,f);CHKERRQ(ierr);
1061   ierr = MatDestroyMatrices(1,&Aoffs);CHKERRQ(ierr);
1062   ierr = MatDestroyMatrices(1,&Boffs);CHKERRQ(ierr);
1063   ierr = ISDestroy(&Me);CHKERRQ(ierr);
1064   ierr = ISDestroy(&Notme);CHKERRQ(ierr);
1065   ierr = PetscFree(notme);CHKERRQ(ierr);
1066   PetscFunctionReturn(0);
1067 }
1068 
1069 #undef __FUNCT__
1070 #define __FUNCT__ "MatMultTransposeAdd_MPIAIJ"
1071 PetscErrorCode MatMultTransposeAdd_MPIAIJ(Mat A,Vec xx,Vec yy,Vec zz)
1072 {
1073   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
1074   PetscErrorCode ierr;
1075 
1076   PetscFunctionBegin;
1077   /* do nondiagonal part */
1078   ierr = (*a->B->ops->multtranspose)(a->B,xx,a->lvec);CHKERRQ(ierr);
1079   /* send it on its way */
1080   ierr = VecScatterBegin(a->Mvctx,a->lvec,zz,ADD_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
1081   /* do local part */
1082   ierr = (*a->A->ops->multtransposeadd)(a->A,xx,yy,zz);CHKERRQ(ierr);
1083   /* receive remote parts */
1084   ierr = VecScatterEnd(a->Mvctx,a->lvec,zz,ADD_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
1085   PetscFunctionReturn(0);
1086 }
1087 
1088 /*
1089   This only works correctly for square matrices where the subblock A->A is the
1090    diagonal block
1091 */
1092 #undef __FUNCT__
1093 #define __FUNCT__ "MatGetDiagonal_MPIAIJ"
1094 PetscErrorCode MatGetDiagonal_MPIAIJ(Mat A,Vec v)
1095 {
1096   PetscErrorCode ierr;
1097   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
1098 
1099   PetscFunctionBegin;
1100   if (A->rmap->N != A->cmap->N) SETERRQ(PetscObjectComm((PetscObject)A),PETSC_ERR_SUP,"Supports only square matrix where A->A is diag block");
1101   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");
1102   ierr = MatGetDiagonal(a->A,v);CHKERRQ(ierr);
1103   PetscFunctionReturn(0);
1104 }
1105 
1106 #undef __FUNCT__
1107 #define __FUNCT__ "MatScale_MPIAIJ"
1108 PetscErrorCode MatScale_MPIAIJ(Mat A,PetscScalar aa)
1109 {
1110   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
1111   PetscErrorCode ierr;
1112 
1113   PetscFunctionBegin;
1114   ierr = MatScale(a->A,aa);CHKERRQ(ierr);
1115   ierr = MatScale(a->B,aa);CHKERRQ(ierr);
1116   PetscFunctionReturn(0);
1117 }
1118 
1119 #undef __FUNCT__
1120 #define __FUNCT__ "MatDestroy_Redundant"
1121 PetscErrorCode MatDestroy_Redundant(Mat_Redundant **redundant)
1122 {
1123   PetscErrorCode ierr;
1124   Mat_Redundant  *redund = *redundant;
1125   PetscInt       i;
1126 
1127   PetscFunctionBegin;
1128   *redundant = NULL;
1129   if (redund){
1130     if (redund->matseq) { /* via MatGetSubMatrices()  */
1131       ierr = ISDestroy(&redund->isrow);CHKERRQ(ierr);
1132       ierr = ISDestroy(&redund->iscol);CHKERRQ(ierr);
1133       ierr = MatDestroy(&redund->matseq[0]);CHKERRQ(ierr);
1134       ierr = PetscFree(redund->matseq);CHKERRQ(ierr);
1135     } else {
1136       ierr = PetscFree2(redund->send_rank,redund->recv_rank);CHKERRQ(ierr);
1137       ierr = PetscFree(redund->sbuf_j);CHKERRQ(ierr);
1138       ierr = PetscFree(redund->sbuf_a);CHKERRQ(ierr);
1139       for (i=0; i<redund->nrecvs; i++) {
1140         ierr = PetscFree(redund->rbuf_j[i]);CHKERRQ(ierr);
1141         ierr = PetscFree(redund->rbuf_a[i]);CHKERRQ(ierr);
1142       }
1143       ierr = PetscFree4(redund->sbuf_nz,redund->rbuf_nz,redund->rbuf_j,redund->rbuf_a);CHKERRQ(ierr);
1144     }
1145 
1146     if (redund->psubcomm) {
1147       ierr = PetscSubcommDestroy(&redund->psubcomm);CHKERRQ(ierr);
1148     }
1149     ierr = PetscFree(redund);CHKERRQ(ierr);
1150   }
1151   PetscFunctionReturn(0);
1152 }
1153 
1154 #undef __FUNCT__
1155 #define __FUNCT__ "MatDestroy_MPIAIJ"
1156 PetscErrorCode MatDestroy_MPIAIJ(Mat mat)
1157 {
1158   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
1159   PetscErrorCode ierr;
1160 
1161   PetscFunctionBegin;
1162 #if defined(PETSC_USE_LOG)
1163   PetscLogObjectState((PetscObject)mat,"Rows=%D, Cols=%D",mat->rmap->N,mat->cmap->N);
1164 #endif
1165   ierr = MatDestroy_Redundant(&mat->redundant);CHKERRQ(ierr);
1166   ierr = MatStashDestroy_Private(&mat->stash);CHKERRQ(ierr);
1167   ierr = VecDestroy(&aij->diag);CHKERRQ(ierr);
1168   ierr = MatDestroy(&aij->A);CHKERRQ(ierr);
1169   ierr = MatDestroy(&aij->B);CHKERRQ(ierr);
1170 #if defined(PETSC_USE_CTABLE)
1171   ierr = PetscTableDestroy(&aij->colmap);CHKERRQ(ierr);
1172 #else
1173   ierr = PetscFree(aij->colmap);CHKERRQ(ierr);
1174 #endif
1175   ierr = PetscFree(aij->garray);CHKERRQ(ierr);
1176   ierr = VecDestroy(&aij->lvec);CHKERRQ(ierr);
1177   ierr = VecScatterDestroy(&aij->Mvctx);CHKERRQ(ierr);
1178   ierr = PetscFree2(aij->rowvalues,aij->rowindices);CHKERRQ(ierr);
1179   ierr = PetscFree(aij->ld);CHKERRQ(ierr);
1180   ierr = PetscFree(mat->data);CHKERRQ(ierr);
1181 
1182   ierr = PetscObjectChangeTypeName((PetscObject)mat,0);CHKERRQ(ierr);
1183   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatStoreValues_C",NULL);CHKERRQ(ierr);
1184   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatRetrieveValues_C",NULL);CHKERRQ(ierr);
1185   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatGetDiagonalBlock_C",NULL);CHKERRQ(ierr);
1186   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatIsTranspose_C",NULL);CHKERRQ(ierr);
1187   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatMPIAIJSetPreallocation_C",NULL);CHKERRQ(ierr);
1188   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatMPIAIJSetPreallocationCSR_C",NULL);CHKERRQ(ierr);
1189   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatDiagonalScaleLocal_C",NULL);CHKERRQ(ierr);
1190   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatConvert_mpiaij_mpisbaij_C",NULL);CHKERRQ(ierr);
1191 #if defined(PETSC_HAVE_ELEMENTAL)
1192   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatConvert_mpiaij_elemental_C",NULL);CHKERRQ(ierr);
1193 #endif
1194   PetscFunctionReturn(0);
1195 }
1196 
1197 #undef __FUNCT__
1198 #define __FUNCT__ "MatView_MPIAIJ_Binary"
1199 PetscErrorCode MatView_MPIAIJ_Binary(Mat mat,PetscViewer viewer)
1200 {
1201   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
1202   Mat_SeqAIJ     *A   = (Mat_SeqAIJ*)aij->A->data;
1203   Mat_SeqAIJ     *B   = (Mat_SeqAIJ*)aij->B->data;
1204   PetscErrorCode ierr;
1205   PetscMPIInt    rank,size,tag = ((PetscObject)viewer)->tag;
1206   int            fd;
1207   PetscInt       nz,header[4],*row_lengths,*range=0,rlen,i;
1208   PetscInt       nzmax,*column_indices,j,k,col,*garray = aij->garray,cnt,cstart = mat->cmap->rstart,rnz = 0;
1209   PetscScalar    *column_values;
1210   PetscInt       message_count,flowcontrolcount;
1211   FILE           *file;
1212 
1213   PetscFunctionBegin;
1214   ierr = MPI_Comm_rank(PetscObjectComm((PetscObject)mat),&rank);CHKERRQ(ierr);
1215   ierr = MPI_Comm_size(PetscObjectComm((PetscObject)mat),&size);CHKERRQ(ierr);
1216   nz   = A->nz + B->nz;
1217   if (!rank) {
1218     header[0] = MAT_FILE_CLASSID;
1219     header[1] = mat->rmap->N;
1220     header[2] = mat->cmap->N;
1221 
1222     ierr = MPI_Reduce(&nz,&header[3],1,MPIU_INT,MPI_SUM,0,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1223     ierr = PetscViewerBinaryGetDescriptor(viewer,&fd);CHKERRQ(ierr);
1224     ierr = PetscBinaryWrite(fd,header,4,PETSC_INT,PETSC_TRUE);CHKERRQ(ierr);
1225     /* get largest number of rows any processor has */
1226     rlen  = mat->rmap->n;
1227     range = mat->rmap->range;
1228     for (i=1; i<size; i++) rlen = PetscMax(rlen,range[i+1] - range[i]);
1229   } else {
1230     ierr = MPI_Reduce(&nz,0,1,MPIU_INT,MPI_SUM,0,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1231     rlen = mat->rmap->n;
1232   }
1233 
1234   /* load up the local row counts */
1235   ierr = PetscMalloc1((rlen+1),&row_lengths);CHKERRQ(ierr);
1236   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];
1237 
1238   /* store the row lengths to the file */
1239   ierr = PetscViewerFlowControlStart(viewer,&message_count,&flowcontrolcount);CHKERRQ(ierr);
1240   if (!rank) {
1241     ierr = PetscBinaryWrite(fd,row_lengths,mat->rmap->n,PETSC_INT,PETSC_TRUE);CHKERRQ(ierr);
1242     for (i=1; i<size; i++) {
1243       ierr = PetscViewerFlowControlStepMaster(viewer,i,&message_count,flowcontrolcount);CHKERRQ(ierr);
1244       rlen = range[i+1] - range[i];
1245       ierr = MPIULong_Recv(row_lengths,rlen,MPIU_INT,i,tag,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1246       ierr = PetscBinaryWrite(fd,row_lengths,rlen,PETSC_INT,PETSC_TRUE);CHKERRQ(ierr);
1247     }
1248     ierr = PetscViewerFlowControlEndMaster(viewer,&message_count);CHKERRQ(ierr);
1249   } else {
1250     ierr = PetscViewerFlowControlStepWorker(viewer,rank,&message_count);CHKERRQ(ierr);
1251     ierr = MPIULong_Send(row_lengths,mat->rmap->n,MPIU_INT,0,tag,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1252     ierr = PetscViewerFlowControlEndWorker(viewer,&message_count);CHKERRQ(ierr);
1253   }
1254   ierr = PetscFree(row_lengths);CHKERRQ(ierr);
1255 
1256   /* load up the local column indices */
1257   nzmax = nz; /* th processor needs space a largest processor needs */
1258   ierr  = MPI_Reduce(&nz,&nzmax,1,MPIU_INT,MPI_MAX,0,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1259   ierr  = PetscMalloc1((nzmax+1),&column_indices);CHKERRQ(ierr);
1260   cnt   = 0;
1261   for (i=0; i<mat->rmap->n; i++) {
1262     for (j=B->i[i]; j<B->i[i+1]; j++) {
1263       if ((col = garray[B->j[j]]) > cstart) break;
1264       column_indices[cnt++] = col;
1265     }
1266     for (k=A->i[i]; k<A->i[i+1]; k++) column_indices[cnt++] = A->j[k] + cstart;
1267     for (; j<B->i[i+1]; j++) column_indices[cnt++] = garray[B->j[j]];
1268   }
1269   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);
1270 
1271   /* store the column indices to the file */
1272   ierr = PetscViewerFlowControlStart(viewer,&message_count,&flowcontrolcount);CHKERRQ(ierr);
1273   if (!rank) {
1274     MPI_Status status;
1275     ierr = PetscBinaryWrite(fd,column_indices,nz,PETSC_INT,PETSC_TRUE);CHKERRQ(ierr);
1276     for (i=1; i<size; i++) {
1277       ierr = PetscViewerFlowControlStepMaster(viewer,i,&message_count,flowcontrolcount);CHKERRQ(ierr);
1278       ierr = MPI_Recv(&rnz,1,MPIU_INT,i,tag,PetscObjectComm((PetscObject)mat),&status);CHKERRQ(ierr);
1279       if (rnz > nzmax) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_LIB,"Internal PETSc error: nz = %D nzmax = %D",nz,nzmax);
1280       ierr = MPIULong_Recv(column_indices,rnz,MPIU_INT,i,tag,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1281       ierr = PetscBinaryWrite(fd,column_indices,rnz,PETSC_INT,PETSC_TRUE);CHKERRQ(ierr);
1282     }
1283     ierr = PetscViewerFlowControlEndMaster(viewer,&message_count);CHKERRQ(ierr);
1284   } else {
1285     ierr = PetscViewerFlowControlStepWorker(viewer,rank,&message_count);CHKERRQ(ierr);
1286     ierr = MPI_Send(&nz,1,MPIU_INT,0,tag,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1287     ierr = MPIULong_Send(column_indices,nz,MPIU_INT,0,tag,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1288     ierr = PetscViewerFlowControlEndWorker(viewer,&message_count);CHKERRQ(ierr);
1289   }
1290   ierr = PetscFree(column_indices);CHKERRQ(ierr);
1291 
1292   /* load up the local column values */
1293   ierr = PetscMalloc1((nzmax+1),&column_values);CHKERRQ(ierr);
1294   cnt  = 0;
1295   for (i=0; i<mat->rmap->n; i++) {
1296     for (j=B->i[i]; j<B->i[i+1]; j++) {
1297       if (garray[B->j[j]] > cstart) break;
1298       column_values[cnt++] = B->a[j];
1299     }
1300     for (k=A->i[i]; k<A->i[i+1]; k++) column_values[cnt++] = A->a[k];
1301     for (; j<B->i[i+1]; j++) column_values[cnt++] = B->a[j];
1302   }
1303   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);
1304 
1305   /* store the column values to the file */
1306   ierr = PetscViewerFlowControlStart(viewer,&message_count,&flowcontrolcount);CHKERRQ(ierr);
1307   if (!rank) {
1308     MPI_Status status;
1309     ierr = PetscBinaryWrite(fd,column_values,nz,PETSC_SCALAR,PETSC_TRUE);CHKERRQ(ierr);
1310     for (i=1; i<size; i++) {
1311       ierr = PetscViewerFlowControlStepMaster(viewer,i,&message_count,flowcontrolcount);CHKERRQ(ierr);
1312       ierr = MPI_Recv(&rnz,1,MPIU_INT,i,tag,PetscObjectComm((PetscObject)mat),&status);CHKERRQ(ierr);
1313       if (rnz > nzmax) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_LIB,"Internal PETSc error: nz = %D nzmax = %D",nz,nzmax);
1314       ierr = MPIULong_Recv(column_values,rnz,MPIU_SCALAR,i,tag,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1315       ierr = PetscBinaryWrite(fd,column_values,rnz,PETSC_SCALAR,PETSC_TRUE);CHKERRQ(ierr);
1316     }
1317     ierr = PetscViewerFlowControlEndMaster(viewer,&message_count);CHKERRQ(ierr);
1318   } else {
1319     ierr = PetscViewerFlowControlStepWorker(viewer,rank,&message_count);CHKERRQ(ierr);
1320     ierr = MPI_Send(&nz,1,MPIU_INT,0,tag,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1321     ierr = MPIULong_Send(column_values,nz,MPIU_SCALAR,0,tag,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1322     ierr = PetscViewerFlowControlEndWorker(viewer,&message_count);CHKERRQ(ierr);
1323   }
1324   ierr = PetscFree(column_values);CHKERRQ(ierr);
1325 
1326   ierr = PetscViewerBinaryGetInfoPointer(viewer,&file);CHKERRQ(ierr);
1327   if (file) fprintf(file,"-matload_block_size %d\n",(int)PetscAbs(mat->rmap->bs));
1328   PetscFunctionReturn(0);
1329 }
1330 
1331 #include <petscdraw.h>
1332 #undef __FUNCT__
1333 #define __FUNCT__ "MatView_MPIAIJ_ASCIIorDraworSocket"
1334 PetscErrorCode MatView_MPIAIJ_ASCIIorDraworSocket(Mat mat,PetscViewer viewer)
1335 {
1336   Mat_MPIAIJ        *aij = (Mat_MPIAIJ*)mat->data;
1337   PetscErrorCode    ierr;
1338   PetscMPIInt       rank = aij->rank,size = aij->size;
1339   PetscBool         isdraw,iascii,isbinary;
1340   PetscViewer       sviewer;
1341   PetscViewerFormat format;
1342 
1343   PetscFunctionBegin;
1344   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERDRAW,&isdraw);CHKERRQ(ierr);
1345   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERASCII,&iascii);CHKERRQ(ierr);
1346   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERBINARY,&isbinary);CHKERRQ(ierr);
1347   if (iascii) {
1348     ierr = PetscViewerGetFormat(viewer,&format);CHKERRQ(ierr);
1349     if (format == PETSC_VIEWER_ASCII_INFO_DETAIL) {
1350       MatInfo   info;
1351       PetscBool inodes;
1352 
1353       ierr = MPI_Comm_rank(PetscObjectComm((PetscObject)mat),&rank);CHKERRQ(ierr);
1354       ierr = MatGetInfo(mat,MAT_LOCAL,&info);CHKERRQ(ierr);
1355       ierr = MatInodeGetInodeSizes(aij->A,NULL,(PetscInt**)&inodes,NULL);CHKERRQ(ierr);
1356       ierr = PetscViewerASCIISynchronizedAllow(viewer,PETSC_TRUE);CHKERRQ(ierr);
1357       if (!inodes) {
1358         ierr = PetscViewerASCIISynchronizedPrintf(viewer,"[%d] Local rows %D nz %D nz alloced %D mem %D, not using I-node routines\n",
1359                                                   rank,mat->rmap->n,(PetscInt)info.nz_used,(PetscInt)info.nz_allocated,(PetscInt)info.memory);CHKERRQ(ierr);
1360       } else {
1361         ierr = PetscViewerASCIISynchronizedPrintf(viewer,"[%d] Local rows %D nz %D nz alloced %D mem %D, using I-node routines\n",
1362                                                   rank,mat->rmap->n,(PetscInt)info.nz_used,(PetscInt)info.nz_allocated,(PetscInt)info.memory);CHKERRQ(ierr);
1363       }
1364       ierr = MatGetInfo(aij->A,MAT_LOCAL,&info);CHKERRQ(ierr);
1365       ierr = PetscViewerASCIISynchronizedPrintf(viewer,"[%d] on-diagonal part: nz %D \n",rank,(PetscInt)info.nz_used);CHKERRQ(ierr);
1366       ierr = MatGetInfo(aij->B,MAT_LOCAL,&info);CHKERRQ(ierr);
1367       ierr = PetscViewerASCIISynchronizedPrintf(viewer,"[%d] off-diagonal part: nz %D \n",rank,(PetscInt)info.nz_used);CHKERRQ(ierr);
1368       ierr = PetscViewerFlush(viewer);CHKERRQ(ierr);
1369       ierr = PetscViewerASCIISynchronizedAllow(viewer,PETSC_FALSE);CHKERRQ(ierr);
1370       ierr = PetscViewerASCIIPrintf(viewer,"Information on VecScatter used in matrix-vector product: \n");CHKERRQ(ierr);
1371       ierr = VecScatterView(aij->Mvctx,viewer);CHKERRQ(ierr);
1372       PetscFunctionReturn(0);
1373     } else if (format == PETSC_VIEWER_ASCII_INFO) {
1374       PetscInt inodecount,inodelimit,*inodes;
1375       ierr = MatInodeGetInodeSizes(aij->A,&inodecount,&inodes,&inodelimit);CHKERRQ(ierr);
1376       if (inodes) {
1377         ierr = PetscViewerASCIIPrintf(viewer,"using I-node (on process 0) routines: found %D nodes, limit used is %D\n",inodecount,inodelimit);CHKERRQ(ierr);
1378       } else {
1379         ierr = PetscViewerASCIIPrintf(viewer,"not using I-node (on process 0) routines\n");CHKERRQ(ierr);
1380       }
1381       PetscFunctionReturn(0);
1382     } else if (format == PETSC_VIEWER_ASCII_FACTOR_INFO) {
1383       PetscFunctionReturn(0);
1384     }
1385   } else if (isbinary) {
1386     if (size == 1) {
1387       ierr = PetscObjectSetName((PetscObject)aij->A,((PetscObject)mat)->name);CHKERRQ(ierr);
1388       ierr = MatView(aij->A,viewer);CHKERRQ(ierr);
1389     } else {
1390       ierr = MatView_MPIAIJ_Binary(mat,viewer);CHKERRQ(ierr);
1391     }
1392     PetscFunctionReturn(0);
1393   } else if (isdraw) {
1394     PetscDraw draw;
1395     PetscBool isnull;
1396     ierr = PetscViewerDrawGetDraw(viewer,0,&draw);CHKERRQ(ierr);
1397     ierr = PetscDrawIsNull(draw,&isnull);CHKERRQ(ierr); if (isnull) PetscFunctionReturn(0);
1398   }
1399 
1400   {
1401     /* assemble the entire matrix onto first processor. */
1402     Mat        A;
1403     Mat_SeqAIJ *Aloc;
1404     PetscInt   M = mat->rmap->N,N = mat->cmap->N,m,*ai,*aj,row,*cols,i,*ct;
1405     MatScalar  *a;
1406 
1407     ierr = MatCreate(PetscObjectComm((PetscObject)mat),&A);CHKERRQ(ierr);
1408     if (!rank) {
1409       ierr = MatSetSizes(A,M,N,M,N);CHKERRQ(ierr);
1410     } else {
1411       ierr = MatSetSizes(A,0,0,M,N);CHKERRQ(ierr);
1412     }
1413     /* This is just a temporary matrix, so explicitly using MATMPIAIJ is probably best */
1414     ierr = MatSetType(A,MATMPIAIJ);CHKERRQ(ierr);
1415     ierr = MatMPIAIJSetPreallocation(A,0,NULL,0,NULL);CHKERRQ(ierr);
1416     ierr = MatSetOption(A,MAT_NEW_NONZERO_LOCATION_ERR,PETSC_FALSE);CHKERRQ(ierr);
1417     ierr = PetscLogObjectParent((PetscObject)mat,(PetscObject)A);CHKERRQ(ierr);
1418 
1419     /* copy over the A part */
1420     Aloc = (Mat_SeqAIJ*)aij->A->data;
1421     m    = aij->A->rmap->n; ai = Aloc->i; aj = Aloc->j; a = Aloc->a;
1422     row  = mat->rmap->rstart;
1423     for (i=0; i<ai[m]; i++) aj[i] += mat->cmap->rstart;
1424     for (i=0; i<m; i++) {
1425       ierr = MatSetValues(A,1,&row,ai[i+1]-ai[i],aj,a,INSERT_VALUES);CHKERRQ(ierr);
1426       row++;
1427       a += ai[i+1]-ai[i]; aj += ai[i+1]-ai[i];
1428     }
1429     aj = Aloc->j;
1430     for (i=0; i<ai[m]; i++) aj[i] -= mat->cmap->rstart;
1431 
1432     /* copy over the B part */
1433     Aloc = (Mat_SeqAIJ*)aij->B->data;
1434     m    = aij->B->rmap->n;  ai = Aloc->i; aj = Aloc->j; a = Aloc->a;
1435     row  = mat->rmap->rstart;
1436     ierr = PetscMalloc1((ai[m]+1),&cols);CHKERRQ(ierr);
1437     ct   = cols;
1438     for (i=0; i<ai[m]; i++) cols[i] = aij->garray[aj[i]];
1439     for (i=0; i<m; i++) {
1440       ierr = MatSetValues(A,1,&row,ai[i+1]-ai[i],cols,a,INSERT_VALUES);CHKERRQ(ierr);
1441       row++;
1442       a += ai[i+1]-ai[i]; cols += ai[i+1]-ai[i];
1443     }
1444     ierr = PetscFree(ct);CHKERRQ(ierr);
1445     ierr = MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
1446     ierr = MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
1447     /*
1448        Everyone has to call to draw the matrix since the graphics waits are
1449        synchronized across all processors that share the PetscDraw object
1450     */
1451     ierr = PetscViewerGetSingleton(viewer,&sviewer);CHKERRQ(ierr);
1452     if (!rank) {
1453       ierr = MatView_SeqAIJ(((Mat_MPIAIJ*)(A->data))->A,sviewer);CHKERRQ(ierr);
1454     }
1455     ierr = PetscViewerRestoreSingleton(viewer,&sviewer);CHKERRQ(ierr);
1456     ierr = MatDestroy(&A);CHKERRQ(ierr);
1457   }
1458   PetscFunctionReturn(0);
1459 }
1460 
1461 #undef __FUNCT__
1462 #define __FUNCT__ "MatView_MPIAIJ"
1463 PetscErrorCode MatView_MPIAIJ(Mat mat,PetscViewer viewer)
1464 {
1465   PetscErrorCode ierr;
1466   PetscBool      iascii,isdraw,issocket,isbinary;
1467 
1468   PetscFunctionBegin;
1469   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERASCII,&iascii);CHKERRQ(ierr);
1470   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERDRAW,&isdraw);CHKERRQ(ierr);
1471   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERBINARY,&isbinary);CHKERRQ(ierr);
1472   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERSOCKET,&issocket);CHKERRQ(ierr);
1473   if (iascii || isdraw || isbinary || issocket) {
1474     ierr = MatView_MPIAIJ_ASCIIorDraworSocket(mat,viewer);CHKERRQ(ierr);
1475   }
1476   PetscFunctionReturn(0);
1477 }
1478 
1479 #undef __FUNCT__
1480 #define __FUNCT__ "MatSOR_MPIAIJ"
1481 PetscErrorCode MatSOR_MPIAIJ(Mat matin,Vec bb,PetscReal omega,MatSORType flag,PetscReal fshift,PetscInt its,PetscInt lits,Vec xx)
1482 {
1483   Mat_MPIAIJ     *mat = (Mat_MPIAIJ*)matin->data;
1484   PetscErrorCode ierr;
1485   Vec            bb1 = 0;
1486   PetscBool      hasop;
1487 
1488   PetscFunctionBegin;
1489   if (flag == SOR_APPLY_UPPER) {
1490     ierr = (*mat->A->ops->sor)(mat->A,bb,omega,flag,fshift,lits,1,xx);CHKERRQ(ierr);
1491     PetscFunctionReturn(0);
1492   }
1493 
1494   if (its > 1 || ~flag & SOR_ZERO_INITIAL_GUESS || flag & SOR_EISENSTAT) {
1495     ierr = VecDuplicate(bb,&bb1);CHKERRQ(ierr);
1496   }
1497 
1498   if ((flag & SOR_LOCAL_SYMMETRIC_SWEEP) == SOR_LOCAL_SYMMETRIC_SWEEP) {
1499     if (flag & SOR_ZERO_INITIAL_GUESS) {
1500       ierr = (*mat->A->ops->sor)(mat->A,bb,omega,flag,fshift,lits,1,xx);CHKERRQ(ierr);
1501       its--;
1502     }
1503 
1504     while (its--) {
1505       ierr = VecScatterBegin(mat->Mvctx,xx,mat->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1506       ierr = VecScatterEnd(mat->Mvctx,xx,mat->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1507 
1508       /* update rhs: bb1 = bb - B*x */
1509       ierr = VecScale(mat->lvec,-1.0);CHKERRQ(ierr);
1510       ierr = (*mat->B->ops->multadd)(mat->B,mat->lvec,bb,bb1);CHKERRQ(ierr);
1511 
1512       /* local sweep */
1513       ierr = (*mat->A->ops->sor)(mat->A,bb1,omega,SOR_SYMMETRIC_SWEEP,fshift,lits,1,xx);CHKERRQ(ierr);
1514     }
1515   } else if (flag & SOR_LOCAL_FORWARD_SWEEP) {
1516     if (flag & SOR_ZERO_INITIAL_GUESS) {
1517       ierr = (*mat->A->ops->sor)(mat->A,bb,omega,flag,fshift,lits,1,xx);CHKERRQ(ierr);
1518       its--;
1519     }
1520     while (its--) {
1521       ierr = VecScatterBegin(mat->Mvctx,xx,mat->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1522       ierr = VecScatterEnd(mat->Mvctx,xx,mat->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1523 
1524       /* update rhs: bb1 = bb - B*x */
1525       ierr = VecScale(mat->lvec,-1.0);CHKERRQ(ierr);
1526       ierr = (*mat->B->ops->multadd)(mat->B,mat->lvec,bb,bb1);CHKERRQ(ierr);
1527 
1528       /* local sweep */
1529       ierr = (*mat->A->ops->sor)(mat->A,bb1,omega,SOR_FORWARD_SWEEP,fshift,lits,1,xx);CHKERRQ(ierr);
1530     }
1531   } else if (flag & SOR_LOCAL_BACKWARD_SWEEP) {
1532     if (flag & SOR_ZERO_INITIAL_GUESS) {
1533       ierr = (*mat->A->ops->sor)(mat->A,bb,omega,flag,fshift,lits,1,xx);CHKERRQ(ierr);
1534       its--;
1535     }
1536     while (its--) {
1537       ierr = VecScatterBegin(mat->Mvctx,xx,mat->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1538       ierr = VecScatterEnd(mat->Mvctx,xx,mat->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1539 
1540       /* update rhs: bb1 = bb - B*x */
1541       ierr = VecScale(mat->lvec,-1.0);CHKERRQ(ierr);
1542       ierr = (*mat->B->ops->multadd)(mat->B,mat->lvec,bb,bb1);CHKERRQ(ierr);
1543 
1544       /* local sweep */
1545       ierr = (*mat->A->ops->sor)(mat->A,bb1,omega,SOR_BACKWARD_SWEEP,fshift,lits,1,xx);CHKERRQ(ierr);
1546     }
1547   } else if (flag & SOR_EISENSTAT) {
1548     Vec xx1;
1549 
1550     ierr = VecDuplicate(bb,&xx1);CHKERRQ(ierr);
1551     ierr = (*mat->A->ops->sor)(mat->A,bb,omega,(MatSORType)(SOR_ZERO_INITIAL_GUESS | SOR_LOCAL_BACKWARD_SWEEP),fshift,lits,1,xx);CHKERRQ(ierr);
1552 
1553     ierr = VecScatterBegin(mat->Mvctx,xx,mat->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1554     ierr = VecScatterEnd(mat->Mvctx,xx,mat->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1555     if (!mat->diag) {
1556       ierr = MatCreateVecs(matin,&mat->diag,NULL);CHKERRQ(ierr);
1557       ierr = MatGetDiagonal(matin,mat->diag);CHKERRQ(ierr);
1558     }
1559     ierr = MatHasOperation(matin,MATOP_MULT_DIAGONAL_BLOCK,&hasop);CHKERRQ(ierr);
1560     if (hasop) {
1561       ierr = MatMultDiagonalBlock(matin,xx,bb1);CHKERRQ(ierr);
1562     } else {
1563       ierr = VecPointwiseMult(bb1,mat->diag,xx);CHKERRQ(ierr);
1564     }
1565     ierr = VecAYPX(bb1,(omega-2.0)/omega,bb);CHKERRQ(ierr);
1566 
1567     ierr = MatMultAdd(mat->B,mat->lvec,bb1,bb1);CHKERRQ(ierr);
1568 
1569     /* local sweep */
1570     ierr = (*mat->A->ops->sor)(mat->A,bb1,omega,(MatSORType)(SOR_ZERO_INITIAL_GUESS | SOR_LOCAL_FORWARD_SWEEP),fshift,lits,1,xx1);CHKERRQ(ierr);
1571     ierr = VecAXPY(xx,1.0,xx1);CHKERRQ(ierr);
1572     ierr = VecDestroy(&xx1);CHKERRQ(ierr);
1573   } else SETERRQ(PetscObjectComm((PetscObject)matin),PETSC_ERR_SUP,"Parallel SOR not supported");
1574 
1575   ierr = VecDestroy(&bb1);CHKERRQ(ierr);
1576   PetscFunctionReturn(0);
1577 }
1578 
1579 #undef __FUNCT__
1580 #define __FUNCT__ "MatPermute_MPIAIJ"
1581 PetscErrorCode MatPermute_MPIAIJ(Mat A,IS rowp,IS colp,Mat *B)
1582 {
1583   Mat            aA,aB,Aperm;
1584   const PetscInt *rwant,*cwant,*gcols,*ai,*bi,*aj,*bj;
1585   PetscScalar    *aa,*ba;
1586   PetscInt       i,j,m,n,ng,anz,bnz,*dnnz,*onnz,*tdnnz,*tonnz,*rdest,*cdest,*work,*gcdest;
1587   PetscSF        rowsf,sf;
1588   IS             parcolp = NULL;
1589   PetscBool      done;
1590   PetscErrorCode ierr;
1591 
1592   PetscFunctionBegin;
1593   ierr = MatGetLocalSize(A,&m,&n);CHKERRQ(ierr);
1594   ierr = ISGetIndices(rowp,&rwant);CHKERRQ(ierr);
1595   ierr = ISGetIndices(colp,&cwant);CHKERRQ(ierr);
1596   ierr = PetscMalloc3(PetscMax(m,n),&work,m,&rdest,n,&cdest);CHKERRQ(ierr);
1597 
1598   /* Invert row permutation to find out where my rows should go */
1599   ierr = PetscSFCreate(PetscObjectComm((PetscObject)A),&rowsf);CHKERRQ(ierr);
1600   ierr = PetscSFSetGraphLayout(rowsf,A->rmap,A->rmap->n,NULL,PETSC_OWN_POINTER,rwant);CHKERRQ(ierr);
1601   ierr = PetscSFSetFromOptions(rowsf);CHKERRQ(ierr);
1602   for (i=0; i<m; i++) work[i] = A->rmap->rstart + i;
1603   ierr = PetscSFReduceBegin(rowsf,MPIU_INT,work,rdest,MPIU_REPLACE);CHKERRQ(ierr);
1604   ierr = PetscSFReduceEnd(rowsf,MPIU_INT,work,rdest,MPIU_REPLACE);CHKERRQ(ierr);
1605 
1606   /* Invert column permutation to find out where my columns should go */
1607   ierr = PetscSFCreate(PetscObjectComm((PetscObject)A),&sf);CHKERRQ(ierr);
1608   ierr = PetscSFSetGraphLayout(sf,A->cmap,A->cmap->n,NULL,PETSC_OWN_POINTER,cwant);CHKERRQ(ierr);
1609   ierr = PetscSFSetFromOptions(sf);CHKERRQ(ierr);
1610   for (i=0; i<n; i++) work[i] = A->cmap->rstart + i;
1611   ierr = PetscSFReduceBegin(sf,MPIU_INT,work,cdest,MPIU_REPLACE);CHKERRQ(ierr);
1612   ierr = PetscSFReduceEnd(sf,MPIU_INT,work,cdest,MPIU_REPLACE);CHKERRQ(ierr);
1613   ierr = PetscSFDestroy(&sf);CHKERRQ(ierr);
1614 
1615   ierr = ISRestoreIndices(rowp,&rwant);CHKERRQ(ierr);
1616   ierr = ISRestoreIndices(colp,&cwant);CHKERRQ(ierr);
1617   ierr = MatMPIAIJGetSeqAIJ(A,&aA,&aB,&gcols);CHKERRQ(ierr);
1618 
1619   /* Find out where my gcols should go */
1620   ierr = MatGetSize(aB,NULL,&ng);CHKERRQ(ierr);
1621   ierr = PetscMalloc1(ng,&gcdest);CHKERRQ(ierr);
1622   ierr = PetscSFCreate(PetscObjectComm((PetscObject)A),&sf);CHKERRQ(ierr);
1623   ierr = PetscSFSetGraphLayout(sf,A->cmap,ng,NULL,PETSC_OWN_POINTER,gcols);CHKERRQ(ierr);
1624   ierr = PetscSFSetFromOptions(sf);CHKERRQ(ierr);
1625   ierr = PetscSFBcastBegin(sf,MPIU_INT,cdest,gcdest);CHKERRQ(ierr);
1626   ierr = PetscSFBcastEnd(sf,MPIU_INT,cdest,gcdest);CHKERRQ(ierr);
1627   ierr = PetscSFDestroy(&sf);CHKERRQ(ierr);
1628 
1629   ierr = PetscCalloc4(m,&dnnz,m,&onnz,m,&tdnnz,m,&tonnz);CHKERRQ(ierr);
1630   ierr = MatGetRowIJ(aA,0,PETSC_FALSE,PETSC_FALSE,&anz,&ai,&aj,&done);CHKERRQ(ierr);
1631   ierr = MatGetRowIJ(aB,0,PETSC_FALSE,PETSC_FALSE,&bnz,&bi,&bj,&done);CHKERRQ(ierr);
1632   for (i=0; i<m; i++) {
1633     PetscInt row = rdest[i],rowner;
1634     ierr = PetscLayoutFindOwner(A->rmap,row,&rowner);CHKERRQ(ierr);
1635     for (j=ai[i]; j<ai[i+1]; j++) {
1636       PetscInt cowner,col = cdest[aj[j]];
1637       ierr = PetscLayoutFindOwner(A->cmap,col,&cowner);CHKERRQ(ierr); /* Could build an index for the columns to eliminate this search */
1638       if (rowner == cowner) dnnz[i]++;
1639       else onnz[i]++;
1640     }
1641     for (j=bi[i]; j<bi[i+1]; j++) {
1642       PetscInt cowner,col = gcdest[bj[j]];
1643       ierr = PetscLayoutFindOwner(A->cmap,col,&cowner);CHKERRQ(ierr);
1644       if (rowner == cowner) dnnz[i]++;
1645       else onnz[i]++;
1646     }
1647   }
1648   ierr = PetscSFBcastBegin(rowsf,MPIU_INT,dnnz,tdnnz);CHKERRQ(ierr);
1649   ierr = PetscSFBcastEnd(rowsf,MPIU_INT,dnnz,tdnnz);CHKERRQ(ierr);
1650   ierr = PetscSFBcastBegin(rowsf,MPIU_INT,onnz,tonnz);CHKERRQ(ierr);
1651   ierr = PetscSFBcastEnd(rowsf,MPIU_INT,onnz,tonnz);CHKERRQ(ierr);
1652   ierr = PetscSFDestroy(&rowsf);CHKERRQ(ierr);
1653 
1654   ierr = MatCreateAIJ(PetscObjectComm((PetscObject)A),A->rmap->n,A->cmap->n,A->rmap->N,A->cmap->N,0,tdnnz,0,tonnz,&Aperm);CHKERRQ(ierr);
1655   ierr = MatSeqAIJGetArray(aA,&aa);CHKERRQ(ierr);
1656   ierr = MatSeqAIJGetArray(aB,&ba);CHKERRQ(ierr);
1657   for (i=0; i<m; i++) {
1658     PetscInt *acols = dnnz,*bcols = onnz; /* Repurpose now-unneeded arrays */
1659     PetscInt j0,rowlen;
1660     rowlen = ai[i+1] - ai[i];
1661     for (j0=j=0; j<rowlen; j0=j) { /* rowlen could be larger than number of rows m, so sum in batches */
1662       for ( ; j<PetscMin(rowlen,j0+m); j++) acols[j-j0] = cdest[aj[ai[i]+j]];
1663       ierr = MatSetValues(Aperm,1,&rdest[i],j-j0,acols,aa+ai[i]+j0,INSERT_VALUES);CHKERRQ(ierr);
1664     }
1665     rowlen = bi[i+1] - bi[i];
1666     for (j0=j=0; j<rowlen; j0=j) {
1667       for ( ; j<PetscMin(rowlen,j0+m); j++) bcols[j-j0] = gcdest[bj[bi[i]+j]];
1668       ierr = MatSetValues(Aperm,1,&rdest[i],j-j0,bcols,ba+bi[i]+j0,INSERT_VALUES);CHKERRQ(ierr);
1669     }
1670   }
1671   ierr = MatAssemblyBegin(Aperm,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
1672   ierr = MatAssemblyEnd(Aperm,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
1673   ierr = MatRestoreRowIJ(aA,0,PETSC_FALSE,PETSC_FALSE,&anz,&ai,&aj,&done);CHKERRQ(ierr);
1674   ierr = MatRestoreRowIJ(aB,0,PETSC_FALSE,PETSC_FALSE,&bnz,&bi,&bj,&done);CHKERRQ(ierr);
1675   ierr = MatSeqAIJRestoreArray(aA,&aa);CHKERRQ(ierr);
1676   ierr = MatSeqAIJRestoreArray(aB,&ba);CHKERRQ(ierr);
1677   ierr = PetscFree4(dnnz,onnz,tdnnz,tonnz);CHKERRQ(ierr);
1678   ierr = PetscFree3(work,rdest,cdest);CHKERRQ(ierr);
1679   ierr = PetscFree(gcdest);CHKERRQ(ierr);
1680   if (parcolp) {ierr = ISDestroy(&colp);CHKERRQ(ierr);}
1681   *B = Aperm;
1682   PetscFunctionReturn(0);
1683 }
1684 
1685 #undef __FUNCT__
1686 #define __FUNCT__ "MatGetInfo_MPIAIJ"
1687 PetscErrorCode MatGetInfo_MPIAIJ(Mat matin,MatInfoType flag,MatInfo *info)
1688 {
1689   Mat_MPIAIJ     *mat = (Mat_MPIAIJ*)matin->data;
1690   Mat            A    = mat->A,B = mat->B;
1691   PetscErrorCode ierr;
1692   PetscReal      isend[5],irecv[5];
1693 
1694   PetscFunctionBegin;
1695   info->block_size = 1.0;
1696   ierr             = MatGetInfo(A,MAT_LOCAL,info);CHKERRQ(ierr);
1697 
1698   isend[0] = info->nz_used; isend[1] = info->nz_allocated; isend[2] = info->nz_unneeded;
1699   isend[3] = info->memory;  isend[4] = info->mallocs;
1700 
1701   ierr = MatGetInfo(B,MAT_LOCAL,info);CHKERRQ(ierr);
1702 
1703   isend[0] += info->nz_used; isend[1] += info->nz_allocated; isend[2] += info->nz_unneeded;
1704   isend[3] += info->memory;  isend[4] += info->mallocs;
1705   if (flag == MAT_LOCAL) {
1706     info->nz_used      = isend[0];
1707     info->nz_allocated = isend[1];
1708     info->nz_unneeded  = isend[2];
1709     info->memory       = isend[3];
1710     info->mallocs      = isend[4];
1711   } else if (flag == MAT_GLOBAL_MAX) {
1712     ierr = MPI_Allreduce(isend,irecv,5,MPIU_REAL,MPIU_MAX,PetscObjectComm((PetscObject)matin));CHKERRQ(ierr);
1713 
1714     info->nz_used      = irecv[0];
1715     info->nz_allocated = irecv[1];
1716     info->nz_unneeded  = irecv[2];
1717     info->memory       = irecv[3];
1718     info->mallocs      = irecv[4];
1719   } else if (flag == MAT_GLOBAL_SUM) {
1720     ierr = MPI_Allreduce(isend,irecv,5,MPIU_REAL,MPIU_SUM,PetscObjectComm((PetscObject)matin));CHKERRQ(ierr);
1721 
1722     info->nz_used      = irecv[0];
1723     info->nz_allocated = irecv[1];
1724     info->nz_unneeded  = irecv[2];
1725     info->memory       = irecv[3];
1726     info->mallocs      = irecv[4];
1727   }
1728   info->fill_ratio_given  = 0; /* no parallel LU/ILU/Cholesky */
1729   info->fill_ratio_needed = 0;
1730   info->factor_mallocs    = 0;
1731   PetscFunctionReturn(0);
1732 }
1733 
1734 #undef __FUNCT__
1735 #define __FUNCT__ "MatSetOption_MPIAIJ"
1736 PetscErrorCode MatSetOption_MPIAIJ(Mat A,MatOption op,PetscBool flg)
1737 {
1738   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
1739   PetscErrorCode ierr;
1740 
1741   PetscFunctionBegin;
1742   switch (op) {
1743   case MAT_NEW_NONZERO_LOCATIONS:
1744   case MAT_NEW_NONZERO_ALLOCATION_ERR:
1745   case MAT_UNUSED_NONZERO_LOCATION_ERR:
1746   case MAT_KEEP_NONZERO_PATTERN:
1747   case MAT_NEW_NONZERO_LOCATION_ERR:
1748   case MAT_USE_INODES:
1749   case MAT_IGNORE_ZERO_ENTRIES:
1750     MatCheckPreallocated(A,1);
1751     ierr = MatSetOption(a->A,op,flg);CHKERRQ(ierr);
1752     ierr = MatSetOption(a->B,op,flg);CHKERRQ(ierr);
1753     break;
1754   case MAT_ROW_ORIENTED:
1755     a->roworiented = flg;
1756 
1757     ierr = MatSetOption(a->A,op,flg);CHKERRQ(ierr);
1758     ierr = MatSetOption(a->B,op,flg);CHKERRQ(ierr);
1759     break;
1760   case MAT_NEW_DIAGONALS:
1761     ierr = PetscInfo1(A,"Option %s ignored\n",MatOptions[op]);CHKERRQ(ierr);
1762     break;
1763   case MAT_IGNORE_OFF_PROC_ENTRIES:
1764     a->donotstash = flg;
1765     break;
1766   case MAT_SPD:
1767     A->spd_set = PETSC_TRUE;
1768     A->spd     = flg;
1769     if (flg) {
1770       A->symmetric                  = PETSC_TRUE;
1771       A->structurally_symmetric     = PETSC_TRUE;
1772       A->symmetric_set              = PETSC_TRUE;
1773       A->structurally_symmetric_set = PETSC_TRUE;
1774     }
1775     break;
1776   case MAT_SYMMETRIC:
1777     ierr = MatSetOption(a->A,op,flg);CHKERRQ(ierr);
1778     break;
1779   case MAT_STRUCTURALLY_SYMMETRIC:
1780     ierr = MatSetOption(a->A,op,flg);CHKERRQ(ierr);
1781     break;
1782   case MAT_HERMITIAN:
1783     ierr = MatSetOption(a->A,op,flg);CHKERRQ(ierr);
1784     break;
1785   case MAT_SYMMETRY_ETERNAL:
1786     ierr = MatSetOption(a->A,op,flg);CHKERRQ(ierr);
1787     break;
1788   default:
1789     SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_SUP,"unknown option %d",op);
1790   }
1791   PetscFunctionReturn(0);
1792 }
1793 
1794 #undef __FUNCT__
1795 #define __FUNCT__ "MatGetRow_MPIAIJ"
1796 PetscErrorCode MatGetRow_MPIAIJ(Mat matin,PetscInt row,PetscInt *nz,PetscInt **idx,PetscScalar **v)
1797 {
1798   Mat_MPIAIJ     *mat = (Mat_MPIAIJ*)matin->data;
1799   PetscScalar    *vworkA,*vworkB,**pvA,**pvB,*v_p;
1800   PetscErrorCode ierr;
1801   PetscInt       i,*cworkA,*cworkB,**pcA,**pcB,cstart = matin->cmap->rstart;
1802   PetscInt       nztot,nzA,nzB,lrow,rstart = matin->rmap->rstart,rend = matin->rmap->rend;
1803   PetscInt       *cmap,*idx_p;
1804 
1805   PetscFunctionBegin;
1806   if (mat->getrowactive) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"Already active");
1807   mat->getrowactive = PETSC_TRUE;
1808 
1809   if (!mat->rowvalues && (idx || v)) {
1810     /*
1811         allocate enough space to hold information from the longest row.
1812     */
1813     Mat_SeqAIJ *Aa = (Mat_SeqAIJ*)mat->A->data,*Ba = (Mat_SeqAIJ*)mat->B->data;
1814     PetscInt   max = 1,tmp;
1815     for (i=0; i<matin->rmap->n; i++) {
1816       tmp = Aa->i[i+1] - Aa->i[i] + Ba->i[i+1] - Ba->i[i];
1817       if (max < tmp) max = tmp;
1818     }
1819     ierr = PetscMalloc2(max,&mat->rowvalues,max,&mat->rowindices);CHKERRQ(ierr);
1820   }
1821 
1822   if (row < rstart || row >= rend) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Only local rows");
1823   lrow = row - rstart;
1824 
1825   pvA = &vworkA; pcA = &cworkA; pvB = &vworkB; pcB = &cworkB;
1826   if (!v)   {pvA = 0; pvB = 0;}
1827   if (!idx) {pcA = 0; if (!v) pcB = 0;}
1828   ierr  = (*mat->A->ops->getrow)(mat->A,lrow,&nzA,pcA,pvA);CHKERRQ(ierr);
1829   ierr  = (*mat->B->ops->getrow)(mat->B,lrow,&nzB,pcB,pvB);CHKERRQ(ierr);
1830   nztot = nzA + nzB;
1831 
1832   cmap = mat->garray;
1833   if (v  || idx) {
1834     if (nztot) {
1835       /* Sort by increasing column numbers, assuming A and B already sorted */
1836       PetscInt imark = -1;
1837       if (v) {
1838         *v = v_p = mat->rowvalues;
1839         for (i=0; i<nzB; i++) {
1840           if (cmap[cworkB[i]] < cstart) v_p[i] = vworkB[i];
1841           else break;
1842         }
1843         imark = i;
1844         for (i=0; i<nzA; i++)     v_p[imark+i] = vworkA[i];
1845         for (i=imark; i<nzB; i++) v_p[nzA+i]   = vworkB[i];
1846       }
1847       if (idx) {
1848         *idx = idx_p = mat->rowindices;
1849         if (imark > -1) {
1850           for (i=0; i<imark; i++) {
1851             idx_p[i] = cmap[cworkB[i]];
1852           }
1853         } else {
1854           for (i=0; i<nzB; i++) {
1855             if (cmap[cworkB[i]] < cstart) idx_p[i] = cmap[cworkB[i]];
1856             else break;
1857           }
1858           imark = i;
1859         }
1860         for (i=0; i<nzA; i++)     idx_p[imark+i] = cstart + cworkA[i];
1861         for (i=imark; i<nzB; i++) idx_p[nzA+i]   = cmap[cworkB[i]];
1862       }
1863     } else {
1864       if (idx) *idx = 0;
1865       if (v)   *v   = 0;
1866     }
1867   }
1868   *nz  = nztot;
1869   ierr = (*mat->A->ops->restorerow)(mat->A,lrow,&nzA,pcA,pvA);CHKERRQ(ierr);
1870   ierr = (*mat->B->ops->restorerow)(mat->B,lrow,&nzB,pcB,pvB);CHKERRQ(ierr);
1871   PetscFunctionReturn(0);
1872 }
1873 
1874 #undef __FUNCT__
1875 #define __FUNCT__ "MatRestoreRow_MPIAIJ"
1876 PetscErrorCode MatRestoreRow_MPIAIJ(Mat mat,PetscInt row,PetscInt *nz,PetscInt **idx,PetscScalar **v)
1877 {
1878   Mat_MPIAIJ *aij = (Mat_MPIAIJ*)mat->data;
1879 
1880   PetscFunctionBegin;
1881   if (!aij->getrowactive) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"MatGetRow() must be called first");
1882   aij->getrowactive = PETSC_FALSE;
1883   PetscFunctionReturn(0);
1884 }
1885 
1886 #undef __FUNCT__
1887 #define __FUNCT__ "MatNorm_MPIAIJ"
1888 PetscErrorCode MatNorm_MPIAIJ(Mat mat,NormType type,PetscReal *norm)
1889 {
1890   Mat_MPIAIJ     *aij  = (Mat_MPIAIJ*)mat->data;
1891   Mat_SeqAIJ     *amat = (Mat_SeqAIJ*)aij->A->data,*bmat = (Mat_SeqAIJ*)aij->B->data;
1892   PetscErrorCode ierr;
1893   PetscInt       i,j,cstart = mat->cmap->rstart;
1894   PetscReal      sum = 0.0;
1895   MatScalar      *v;
1896 
1897   PetscFunctionBegin;
1898   if (aij->size == 1) {
1899     ierr =  MatNorm(aij->A,type,norm);CHKERRQ(ierr);
1900   } else {
1901     if (type == NORM_FROBENIUS) {
1902       v = amat->a;
1903       for (i=0; i<amat->nz; i++) {
1904         sum += PetscRealPart(PetscConj(*v)*(*v)); v++;
1905       }
1906       v = bmat->a;
1907       for (i=0; i<bmat->nz; i++) {
1908         sum += PetscRealPart(PetscConj(*v)*(*v)); v++;
1909       }
1910       ierr  = MPI_Allreduce(&sum,norm,1,MPIU_REAL,MPIU_SUM,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1911       *norm = PetscSqrtReal(*norm);
1912     } else if (type == NORM_1) { /* max column norm */
1913       PetscReal *tmp,*tmp2;
1914       PetscInt  *jj,*garray = aij->garray;
1915       ierr  = PetscCalloc1((mat->cmap->N+1),&tmp);CHKERRQ(ierr);
1916       ierr  = PetscMalloc1((mat->cmap->N+1),&tmp2);CHKERRQ(ierr);
1917       *norm = 0.0;
1918       v     = amat->a; jj = amat->j;
1919       for (j=0; j<amat->nz; j++) {
1920         tmp[cstart + *jj++] += PetscAbsScalar(*v);  v++;
1921       }
1922       v = bmat->a; jj = bmat->j;
1923       for (j=0; j<bmat->nz; j++) {
1924         tmp[garray[*jj++]] += PetscAbsScalar(*v); v++;
1925       }
1926       ierr = MPI_Allreduce(tmp,tmp2,mat->cmap->N,MPIU_REAL,MPIU_SUM,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1927       for (j=0; j<mat->cmap->N; j++) {
1928         if (tmp2[j] > *norm) *norm = tmp2[j];
1929       }
1930       ierr = PetscFree(tmp);CHKERRQ(ierr);
1931       ierr = PetscFree(tmp2);CHKERRQ(ierr);
1932     } else if (type == NORM_INFINITY) { /* max row norm */
1933       PetscReal ntemp = 0.0;
1934       for (j=0; j<aij->A->rmap->n; j++) {
1935         v   = amat->a + amat->i[j];
1936         sum = 0.0;
1937         for (i=0; i<amat->i[j+1]-amat->i[j]; i++) {
1938           sum += PetscAbsScalar(*v); v++;
1939         }
1940         v = bmat->a + bmat->i[j];
1941         for (i=0; i<bmat->i[j+1]-bmat->i[j]; i++) {
1942           sum += PetscAbsScalar(*v); v++;
1943         }
1944         if (sum > ntemp) ntemp = sum;
1945       }
1946       ierr = MPI_Allreduce(&ntemp,norm,1,MPIU_REAL,MPIU_MAX,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1947     } else SETERRQ(PetscObjectComm((PetscObject)mat),PETSC_ERR_SUP,"No support for two norm");
1948   }
1949   PetscFunctionReturn(0);
1950 }
1951 
1952 #undef __FUNCT__
1953 #define __FUNCT__ "MatTranspose_MPIAIJ"
1954 PetscErrorCode MatTranspose_MPIAIJ(Mat A,MatReuse reuse,Mat *matout)
1955 {
1956   Mat_MPIAIJ     *a   = (Mat_MPIAIJ*)A->data;
1957   Mat_SeqAIJ     *Aloc=(Mat_SeqAIJ*)a->A->data,*Bloc=(Mat_SeqAIJ*)a->B->data;
1958   PetscErrorCode ierr;
1959   PetscInt       M      = A->rmap->N,N = A->cmap->N,ma,na,mb,nb,*ai,*aj,*bi,*bj,row,*cols,*cols_tmp,i;
1960   PetscInt       cstart = A->cmap->rstart,ncol;
1961   Mat            B;
1962   MatScalar      *array;
1963 
1964   PetscFunctionBegin;
1965   if (reuse == MAT_REUSE_MATRIX && A == *matout && M != N) SETERRQ(PetscObjectComm((PetscObject)A),PETSC_ERR_ARG_SIZ,"Square matrix only for in-place");
1966 
1967   ma = A->rmap->n; na = A->cmap->n; mb = a->B->rmap->n; nb = a->B->cmap->n;
1968   ai = Aloc->i; aj = Aloc->j;
1969   bi = Bloc->i; bj = Bloc->j;
1970   if (reuse == MAT_INITIAL_MATRIX || *matout == A) {
1971     PetscInt             *d_nnz,*g_nnz,*o_nnz;
1972     PetscSFNode          *oloc;
1973     PETSC_UNUSED PetscSF sf;
1974 
1975     ierr = PetscMalloc4(na,&d_nnz,na,&o_nnz,nb,&g_nnz,nb,&oloc);CHKERRQ(ierr);
1976     /* compute d_nnz for preallocation */
1977     ierr = PetscMemzero(d_nnz,na*sizeof(PetscInt));CHKERRQ(ierr);
1978     for (i=0; i<ai[ma]; i++) {
1979       d_nnz[aj[i]]++;
1980       aj[i] += cstart; /* global col index to be used by MatSetValues() */
1981     }
1982     /* compute local off-diagonal contributions */
1983     ierr = PetscMemzero(g_nnz,nb*sizeof(PetscInt));CHKERRQ(ierr);
1984     for (i=0; i<bi[ma]; i++) g_nnz[bj[i]]++;
1985     /* map those to global */
1986     ierr = PetscSFCreate(PetscObjectComm((PetscObject)A),&sf);CHKERRQ(ierr);
1987     ierr = PetscSFSetGraphLayout(sf,A->cmap,nb,NULL,PETSC_USE_POINTER,a->garray);CHKERRQ(ierr);
1988     ierr = PetscSFSetFromOptions(sf);CHKERRQ(ierr);
1989     ierr = PetscMemzero(o_nnz,na*sizeof(PetscInt));CHKERRQ(ierr);
1990     ierr = PetscSFReduceBegin(sf,MPIU_INT,g_nnz,o_nnz,MPIU_SUM);CHKERRQ(ierr);
1991     ierr = PetscSFReduceEnd(sf,MPIU_INT,g_nnz,o_nnz,MPIU_SUM);CHKERRQ(ierr);
1992     ierr = PetscSFDestroy(&sf);CHKERRQ(ierr);
1993 
1994     ierr = MatCreate(PetscObjectComm((PetscObject)A),&B);CHKERRQ(ierr);
1995     ierr = MatSetSizes(B,A->cmap->n,A->rmap->n,N,M);CHKERRQ(ierr);
1996     ierr = MatSetBlockSizes(B,PetscAbs(A->cmap->bs),PetscAbs(A->rmap->bs));CHKERRQ(ierr);
1997     ierr = MatSetType(B,((PetscObject)A)->type_name);CHKERRQ(ierr);
1998     ierr = MatMPIAIJSetPreallocation(B,0,d_nnz,0,o_nnz);CHKERRQ(ierr);
1999     ierr = PetscFree4(d_nnz,o_nnz,g_nnz,oloc);CHKERRQ(ierr);
2000   } else {
2001     B    = *matout;
2002     ierr = MatSetOption(B,MAT_NEW_NONZERO_ALLOCATION_ERR,PETSC_TRUE);CHKERRQ(ierr);
2003     for (i=0; i<ai[ma]; i++) aj[i] += cstart; /* global col index to be used by MatSetValues() */
2004   }
2005 
2006   /* copy over the A part */
2007   array = Aloc->a;
2008   row   = A->rmap->rstart;
2009   for (i=0; i<ma; i++) {
2010     ncol = ai[i+1]-ai[i];
2011     ierr = MatSetValues(B,ncol,aj,1,&row,array,INSERT_VALUES);CHKERRQ(ierr);
2012     row++;
2013     array += ncol; aj += ncol;
2014   }
2015   aj = Aloc->j;
2016   for (i=0; i<ai[ma]; i++) aj[i] -= cstart; /* resume local col index */
2017 
2018   /* copy over the B part */
2019   ierr  = PetscCalloc1(bi[mb],&cols);CHKERRQ(ierr);
2020   array = Bloc->a;
2021   row   = A->rmap->rstart;
2022   for (i=0; i<bi[mb]; i++) cols[i] = a->garray[bj[i]];
2023   cols_tmp = cols;
2024   for (i=0; i<mb; i++) {
2025     ncol = bi[i+1]-bi[i];
2026     ierr = MatSetValues(B,ncol,cols_tmp,1,&row,array,INSERT_VALUES);CHKERRQ(ierr);
2027     row++;
2028     array += ncol; cols_tmp += ncol;
2029   }
2030   ierr = PetscFree(cols);CHKERRQ(ierr);
2031 
2032   ierr = MatAssemblyBegin(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
2033   ierr = MatAssemblyEnd(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
2034   if (reuse == MAT_INITIAL_MATRIX || *matout != A) {
2035     *matout = B;
2036   } else {
2037     ierr = MatHeaderMerge(A,B);CHKERRQ(ierr);
2038   }
2039   PetscFunctionReturn(0);
2040 }
2041 
2042 #undef __FUNCT__
2043 #define __FUNCT__ "MatDiagonalScale_MPIAIJ"
2044 PetscErrorCode MatDiagonalScale_MPIAIJ(Mat mat,Vec ll,Vec rr)
2045 {
2046   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
2047   Mat            a    = aij->A,b = aij->B;
2048   PetscErrorCode ierr;
2049   PetscInt       s1,s2,s3;
2050 
2051   PetscFunctionBegin;
2052   ierr = MatGetLocalSize(mat,&s2,&s3);CHKERRQ(ierr);
2053   if (rr) {
2054     ierr = VecGetLocalSize(rr,&s1);CHKERRQ(ierr);
2055     if (s1!=s3) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_SIZ,"right vector non-conforming local size");
2056     /* Overlap communication with computation. */
2057     ierr = VecScatterBegin(aij->Mvctx,rr,aij->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
2058   }
2059   if (ll) {
2060     ierr = VecGetLocalSize(ll,&s1);CHKERRQ(ierr);
2061     if (s1!=s2) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_SIZ,"left vector non-conforming local size");
2062     ierr = (*b->ops->diagonalscale)(b,ll,0);CHKERRQ(ierr);
2063   }
2064   /* scale  the diagonal block */
2065   ierr = (*a->ops->diagonalscale)(a,ll,rr);CHKERRQ(ierr);
2066 
2067   if (rr) {
2068     /* Do a scatter end and then right scale the off-diagonal block */
2069     ierr = VecScatterEnd(aij->Mvctx,rr,aij->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
2070     ierr = (*b->ops->diagonalscale)(b,0,aij->lvec);CHKERRQ(ierr);
2071   }
2072   PetscFunctionReturn(0);
2073 }
2074 
2075 #undef __FUNCT__
2076 #define __FUNCT__ "MatSetUnfactored_MPIAIJ"
2077 PetscErrorCode MatSetUnfactored_MPIAIJ(Mat A)
2078 {
2079   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
2080   PetscErrorCode ierr;
2081 
2082   PetscFunctionBegin;
2083   ierr = MatSetUnfactored(a->A);CHKERRQ(ierr);
2084   PetscFunctionReturn(0);
2085 }
2086 
2087 #undef __FUNCT__
2088 #define __FUNCT__ "MatEqual_MPIAIJ"
2089 PetscErrorCode MatEqual_MPIAIJ(Mat A,Mat B,PetscBool  *flag)
2090 {
2091   Mat_MPIAIJ     *matB = (Mat_MPIAIJ*)B->data,*matA = (Mat_MPIAIJ*)A->data;
2092   Mat            a,b,c,d;
2093   PetscBool      flg;
2094   PetscErrorCode ierr;
2095 
2096   PetscFunctionBegin;
2097   a = matA->A; b = matA->B;
2098   c = matB->A; d = matB->B;
2099 
2100   ierr = MatEqual(a,c,&flg);CHKERRQ(ierr);
2101   if (flg) {
2102     ierr = MatEqual(b,d,&flg);CHKERRQ(ierr);
2103   }
2104   ierr = MPI_Allreduce(&flg,flag,1,MPIU_BOOL,MPI_LAND,PetscObjectComm((PetscObject)A));CHKERRQ(ierr);
2105   PetscFunctionReturn(0);
2106 }
2107 
2108 #undef __FUNCT__
2109 #define __FUNCT__ "MatCopy_MPIAIJ"
2110 PetscErrorCode MatCopy_MPIAIJ(Mat A,Mat B,MatStructure str)
2111 {
2112   PetscErrorCode ierr;
2113   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
2114   Mat_MPIAIJ     *b = (Mat_MPIAIJ*)B->data;
2115 
2116   PetscFunctionBegin;
2117   /* If the two matrices don't have the same copy implementation, they aren't compatible for fast copy. */
2118   if ((str != SAME_NONZERO_PATTERN) || (A->ops->copy != B->ops->copy)) {
2119     /* because of the column compression in the off-processor part of the matrix a->B,
2120        the number of columns in a->B and b->B may be different, hence we cannot call
2121        the MatCopy() directly on the two parts. If need be, we can provide a more
2122        efficient copy than the MatCopy_Basic() by first uncompressing the a->B matrices
2123        then copying the submatrices */
2124     ierr = MatCopy_Basic(A,B,str);CHKERRQ(ierr);
2125   } else {
2126     ierr = MatCopy(a->A,b->A,str);CHKERRQ(ierr);
2127     ierr = MatCopy(a->B,b->B,str);CHKERRQ(ierr);
2128   }
2129   PetscFunctionReturn(0);
2130 }
2131 
2132 #undef __FUNCT__
2133 #define __FUNCT__ "MatSetUp_MPIAIJ"
2134 PetscErrorCode MatSetUp_MPIAIJ(Mat A)
2135 {
2136   PetscErrorCode ierr;
2137 
2138   PetscFunctionBegin;
2139   ierr =  MatMPIAIJSetPreallocation(A,PETSC_DEFAULT,0,PETSC_DEFAULT,0);CHKERRQ(ierr);
2140   PetscFunctionReturn(0);
2141 }
2142 
2143 /*
2144    Computes the number of nonzeros per row needed for preallocation when X and Y
2145    have different nonzero structure.
2146 */
2147 #undef __FUNCT__
2148 #define __FUNCT__ "MatAXPYGetPreallocation_MPIX_private"
2149 PetscErrorCode MatAXPYGetPreallocation_MPIX_private(PetscInt m,const PetscInt *xi,const PetscInt *xj,const PetscInt *xltog,const PetscInt *yi,const PetscInt *yj,const PetscInt *yltog,PetscInt *nnz)
2150 {
2151   PetscInt       i,j,k,nzx,nzy;
2152 
2153   PetscFunctionBegin;
2154   /* Set the number of nonzeros in the new matrix */
2155   for (i=0; i<m; i++) {
2156     const PetscInt *xjj = xj+xi[i],*yjj = yj+yi[i];
2157     nzx = xi[i+1] - xi[i];
2158     nzy = yi[i+1] - yi[i];
2159     nnz[i] = 0;
2160     for (j=0,k=0; j<nzx; j++) {                   /* Point in X */
2161       for (; k<nzy && yltog[yjj[k]]<xltog[xjj[j]]; k++) nnz[i]++; /* Catch up to X */
2162       if (k<nzy && yltog[yjj[k]]==xltog[xjj[j]]) k++;             /* Skip duplicate */
2163       nnz[i]++;
2164     }
2165     for (; k<nzy; k++) nnz[i]++;
2166   }
2167   PetscFunctionReturn(0);
2168 }
2169 
2170 /* This is the same as MatAXPYGetPreallocation_SeqAIJ, except that the local-to-global map is provided */
2171 #undef __FUNCT__
2172 #define __FUNCT__ "MatAXPYGetPreallocation_MPIAIJ"
2173 static PetscErrorCode MatAXPYGetPreallocation_MPIAIJ(Mat Y,const PetscInt *yltog,Mat X,const PetscInt *xltog,PetscInt *nnz)
2174 {
2175   PetscErrorCode ierr;
2176   PetscInt       m = Y->rmap->N;
2177   Mat_SeqAIJ     *x = (Mat_SeqAIJ*)X->data;
2178   Mat_SeqAIJ     *y = (Mat_SeqAIJ*)Y->data;
2179 
2180   PetscFunctionBegin;
2181   ierr = MatAXPYGetPreallocation_MPIX_private(m,x->i,x->j,xltog,y->i,y->j,yltog,nnz);CHKERRQ(ierr);
2182   PetscFunctionReturn(0);
2183 }
2184 
2185 #undef __FUNCT__
2186 #define __FUNCT__ "MatAXPY_MPIAIJ"
2187 PetscErrorCode MatAXPY_MPIAIJ(Mat Y,PetscScalar a,Mat X,MatStructure str)
2188 {
2189   PetscErrorCode ierr;
2190   PetscInt       i;
2191   Mat_MPIAIJ     *xx = (Mat_MPIAIJ*)X->data,*yy = (Mat_MPIAIJ*)Y->data;
2192   PetscBLASInt   bnz,one=1;
2193   Mat_SeqAIJ     *x,*y;
2194 
2195   PetscFunctionBegin;
2196   if (str == SAME_NONZERO_PATTERN) {
2197     PetscScalar alpha = a;
2198     x    = (Mat_SeqAIJ*)xx->A->data;
2199     ierr = PetscBLASIntCast(x->nz,&bnz);CHKERRQ(ierr);
2200     y    = (Mat_SeqAIJ*)yy->A->data;
2201     PetscStackCallBLAS("BLASaxpy",BLASaxpy_(&bnz,&alpha,x->a,&one,y->a,&one));
2202     x    = (Mat_SeqAIJ*)xx->B->data;
2203     y    = (Mat_SeqAIJ*)yy->B->data;
2204     ierr = PetscBLASIntCast(x->nz,&bnz);CHKERRQ(ierr);
2205     PetscStackCallBLAS("BLASaxpy",BLASaxpy_(&bnz,&alpha,x->a,&one,y->a,&one));
2206     ierr = PetscObjectStateIncrease((PetscObject)Y);CHKERRQ(ierr);
2207   } else if (str == SUBSET_NONZERO_PATTERN) {
2208     ierr = MatAXPY_SeqAIJ(yy->A,a,xx->A,str);CHKERRQ(ierr);
2209 
2210     x = (Mat_SeqAIJ*)xx->B->data;
2211     y = (Mat_SeqAIJ*)yy->B->data;
2212     if (y->xtoy && y->XtoY != xx->B) {
2213       ierr = PetscFree(y->xtoy);CHKERRQ(ierr);
2214       ierr = MatDestroy(&y->XtoY);CHKERRQ(ierr);
2215     }
2216     if (!y->xtoy) { /* get xtoy */
2217       ierr    = MatAXPYGetxtoy_Private(xx->B->rmap->n,x->i,x->j,xx->garray,y->i,y->j,yy->garray,&y->xtoy);CHKERRQ(ierr);
2218       y->XtoY = xx->B;
2219       ierr    = PetscObjectReference((PetscObject)xx->B);CHKERRQ(ierr);
2220     }
2221     for (i=0; i<x->nz; i++) y->a[y->xtoy[i]] += a*(x->a[i]);
2222     ierr = PetscObjectStateIncrease((PetscObject)Y);CHKERRQ(ierr);
2223   } else {
2224     Mat      B;
2225     PetscInt *nnz_d,*nnz_o;
2226     ierr = PetscMalloc1(yy->A->rmap->N,&nnz_d);CHKERRQ(ierr);
2227     ierr = PetscMalloc1(yy->B->rmap->N,&nnz_o);CHKERRQ(ierr);
2228     ierr = MatCreate(PetscObjectComm((PetscObject)Y),&B);CHKERRQ(ierr);
2229     ierr = PetscObjectSetName((PetscObject)B,((PetscObject)Y)->name);CHKERRQ(ierr);
2230     ierr = MatSetSizes(B,Y->rmap->n,Y->cmap->n,Y->rmap->N,Y->cmap->N);CHKERRQ(ierr);
2231     ierr = MatSetBlockSizesFromMats(B,Y,Y);CHKERRQ(ierr);
2232     ierr = MatSetType(B,MATMPIAIJ);CHKERRQ(ierr);
2233     ierr = MatAXPYGetPreallocation_SeqAIJ(yy->A,xx->A,nnz_d);CHKERRQ(ierr);
2234     ierr = MatAXPYGetPreallocation_MPIAIJ(yy->B,yy->garray,xx->B,xx->garray,nnz_o);CHKERRQ(ierr);
2235     ierr = MatMPIAIJSetPreallocation(B,0,nnz_d,0,nnz_o);CHKERRQ(ierr);
2236     ierr = MatAXPY_BasicWithPreallocation(B,Y,a,X,str);CHKERRQ(ierr);
2237     ierr = MatHeaderReplace(Y,B);CHKERRQ(ierr);
2238     ierr = PetscFree(nnz_d);CHKERRQ(ierr);
2239     ierr = PetscFree(nnz_o);CHKERRQ(ierr);
2240   }
2241   PetscFunctionReturn(0);
2242 }
2243 
2244 extern PetscErrorCode  MatConjugate_SeqAIJ(Mat);
2245 
2246 #undef __FUNCT__
2247 #define __FUNCT__ "MatConjugate_MPIAIJ"
2248 PetscErrorCode  MatConjugate_MPIAIJ(Mat mat)
2249 {
2250 #if defined(PETSC_USE_COMPLEX)
2251   PetscErrorCode ierr;
2252   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
2253 
2254   PetscFunctionBegin;
2255   ierr = MatConjugate_SeqAIJ(aij->A);CHKERRQ(ierr);
2256   ierr = MatConjugate_SeqAIJ(aij->B);CHKERRQ(ierr);
2257 #else
2258   PetscFunctionBegin;
2259 #endif
2260   PetscFunctionReturn(0);
2261 }
2262 
2263 #undef __FUNCT__
2264 #define __FUNCT__ "MatRealPart_MPIAIJ"
2265 PetscErrorCode MatRealPart_MPIAIJ(Mat A)
2266 {
2267   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
2268   PetscErrorCode ierr;
2269 
2270   PetscFunctionBegin;
2271   ierr = MatRealPart(a->A);CHKERRQ(ierr);
2272   ierr = MatRealPart(a->B);CHKERRQ(ierr);
2273   PetscFunctionReturn(0);
2274 }
2275 
2276 #undef __FUNCT__
2277 #define __FUNCT__ "MatImaginaryPart_MPIAIJ"
2278 PetscErrorCode MatImaginaryPart_MPIAIJ(Mat A)
2279 {
2280   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
2281   PetscErrorCode ierr;
2282 
2283   PetscFunctionBegin;
2284   ierr = MatImaginaryPart(a->A);CHKERRQ(ierr);
2285   ierr = MatImaginaryPart(a->B);CHKERRQ(ierr);
2286   PetscFunctionReturn(0);
2287 }
2288 
2289 #if defined(PETSC_HAVE_PBGL)
2290 
2291 #include <boost/parallel/mpi/bsp_process_group.hpp>
2292 #include <boost/graph/distributed/ilu_default_graph.hpp>
2293 #include <boost/graph/distributed/ilu_0_block.hpp>
2294 #include <boost/graph/distributed/ilu_preconditioner.hpp>
2295 #include <boost/graph/distributed/petsc/interface.hpp>
2296 #include <boost/multi_array.hpp>
2297 #include <boost/parallel/distributed_property_map->hpp>
2298 
2299 #undef __FUNCT__
2300 #define __FUNCT__ "MatILUFactorSymbolic_MPIAIJ"
2301 /*
2302   This uses the parallel ILU factorization of Peter Gottschling <pgottsch@osl.iu.edu>
2303 */
2304 PetscErrorCode MatILUFactorSymbolic_MPIAIJ(Mat fact,Mat A, IS isrow, IS iscol, const MatFactorInfo *info)
2305 {
2306   namespace petsc = boost::distributed::petsc;
2307 
2308   namespace graph_dist = boost::graph::distributed;
2309   using boost::graph::distributed::ilu_default::process_group_type;
2310   using boost::graph::ilu_permuted;
2311 
2312   PetscBool      row_identity, col_identity;
2313   PetscContainer c;
2314   PetscInt       m, n, M, N;
2315   PetscErrorCode ierr;
2316 
2317   PetscFunctionBegin;
2318   if (info->levels != 0) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_SUP,"Only levels = 0 supported for parallel ilu");
2319   ierr = ISIdentity(isrow, &row_identity);CHKERRQ(ierr);
2320   ierr = ISIdentity(iscol, &col_identity);CHKERRQ(ierr);
2321   if (!row_identity || !col_identity) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONG,"Row and column permutations must be identity for parallel ILU");
2322 
2323   process_group_type pg;
2324   typedef graph_dist::ilu_default::ilu_level_graph_type lgraph_type;
2325   lgraph_type  *lgraph_p   = new lgraph_type(petsc::num_global_vertices(A), pg, petsc::matrix_distribution(A, pg));
2326   lgraph_type& level_graph = *lgraph_p;
2327   graph_dist::ilu_default::graph_type&            graph(level_graph.graph);
2328 
2329   petsc::read_matrix(A, graph, get(boost::edge_weight, graph));
2330   ilu_permuted(level_graph);
2331 
2332   /* put together the new matrix */
2333   ierr = MatCreate(PetscObjectComm((PetscObject)A), fact);CHKERRQ(ierr);
2334   ierr = MatGetLocalSize(A, &m, &n);CHKERRQ(ierr);
2335   ierr = MatGetSize(A, &M, &N);CHKERRQ(ierr);
2336   ierr = MatSetSizes(fact, m, n, M, N);CHKERRQ(ierr);
2337   ierr = MatSetBlockSizesFromMats(fact,A,A);CHKERRQ(ierr);
2338   ierr = MatSetType(fact, ((PetscObject)A)->type_name);CHKERRQ(ierr);
2339   ierr = MatAssemblyBegin(fact, MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
2340   ierr = MatAssemblyEnd(fact, MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
2341 
2342   ierr = PetscContainerCreate(PetscObjectComm((PetscObject)A), &c);
2343   ierr = PetscContainerSetPointer(c, lgraph_p);
2344   ierr = PetscObjectCompose((PetscObject) (fact), "graph", (PetscObject) c);
2345   ierr = PetscContainerDestroy(&c);
2346   PetscFunctionReturn(0);
2347 }
2348 
2349 #undef __FUNCT__
2350 #define __FUNCT__ "MatLUFactorNumeric_MPIAIJ"
2351 PetscErrorCode MatLUFactorNumeric_MPIAIJ(Mat B,Mat A, const MatFactorInfo *info)
2352 {
2353   PetscFunctionBegin;
2354   PetscFunctionReturn(0);
2355 }
2356 
2357 #undef __FUNCT__
2358 #define __FUNCT__ "MatSolve_MPIAIJ"
2359 /*
2360   This uses the parallel ILU factorization of Peter Gottschling <pgottsch@osl.iu.edu>
2361 */
2362 PetscErrorCode MatSolve_MPIAIJ(Mat A, Vec b, Vec x)
2363 {
2364   namespace graph_dist = boost::graph::distributed;
2365 
2366   typedef graph_dist::ilu_default::ilu_level_graph_type lgraph_type;
2367   lgraph_type    *lgraph_p;
2368   PetscContainer c;
2369   PetscErrorCode ierr;
2370 
2371   PetscFunctionBegin;
2372   ierr = PetscObjectQuery((PetscObject) A, "graph", (PetscObject*) &c);CHKERRQ(ierr);
2373   ierr = PetscContainerGetPointer(c, (void**) &lgraph_p);CHKERRQ(ierr);
2374   ierr = VecCopy(b, x);CHKERRQ(ierr);
2375 
2376   PetscScalar *array_x;
2377   ierr = VecGetArray(x, &array_x);CHKERRQ(ierr);
2378   PetscInt sx;
2379   ierr = VecGetSize(x, &sx);CHKERRQ(ierr);
2380 
2381   PetscScalar *array_b;
2382   ierr = VecGetArray(b, &array_b);CHKERRQ(ierr);
2383   PetscInt sb;
2384   ierr = VecGetSize(b, &sb);CHKERRQ(ierr);
2385 
2386   lgraph_type& level_graph = *lgraph_p;
2387   graph_dist::ilu_default::graph_type&            graph(level_graph.graph);
2388 
2389   typedef boost::multi_array_ref<PetscScalar, 1> array_ref_type;
2390   array_ref_type                                 ref_b(array_b, boost::extents[num_vertices(graph)]);
2391   array_ref_type                                 ref_x(array_x, boost::extents[num_vertices(graph)]);
2392 
2393   typedef boost::iterator_property_map<array_ref_type::iterator,
2394                                        boost::property_map<graph_dist::ilu_default::graph_type, boost::vertex_index_t>::type>  gvector_type;
2395   gvector_type                                   vector_b(ref_b.begin(), get(boost::vertex_index, graph));
2396   gvector_type                                   vector_x(ref_x.begin(), get(boost::vertex_index, graph));
2397 
2398   ilu_set_solve(*lgraph_p, vector_b, vector_x);
2399   PetscFunctionReturn(0);
2400 }
2401 #endif
2402 
2403 
2404 #undef __FUNCT__
2405 #define __FUNCT__ "MatGetRedundantMatrix_MPIAIJ_interlaced"
2406 PetscErrorCode MatGetRedundantMatrix_MPIAIJ_interlaced(Mat mat,PetscInt nsubcomm,MPI_Comm subcomm,MatReuse reuse,Mat *matredundant)
2407 {
2408   PetscMPIInt    rank,size;
2409   MPI_Comm       comm;
2410   PetscErrorCode ierr;
2411   PetscInt       nsends=0,nrecvs=0,i,rownz_max=0,M=mat->rmap->N,N=mat->cmap->N;
2412   PetscMPIInt    *send_rank= NULL,*recv_rank=NULL,subrank,subsize;
2413   PetscInt       *rowrange = mat->rmap->range;
2414   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
2415   Mat            A = aij->A,B=aij->B,C=*matredundant;
2416   Mat_SeqAIJ     *a = (Mat_SeqAIJ*)A->data,*b=(Mat_SeqAIJ*)B->data;
2417   PetscScalar    *sbuf_a;
2418   PetscInt       nzlocal=a->nz+b->nz;
2419   PetscInt       j,cstart=mat->cmap->rstart,cend=mat->cmap->rend,row,nzA,nzB,ncols,*cworkA,*cworkB;
2420   PetscInt       rstart=mat->rmap->rstart,rend=mat->rmap->rend,*bmap=aij->garray;
2421   PetscInt       *cols,ctmp,lwrite,*rptr,l,*sbuf_j;
2422   MatScalar      *aworkA,*aworkB;
2423   PetscScalar    *vals;
2424   PetscMPIInt    tag1,tag2,tag3,imdex;
2425   MPI_Request    *s_waits1=NULL,*s_waits2=NULL,*s_waits3=NULL;
2426   MPI_Request    *r_waits1=NULL,*r_waits2=NULL,*r_waits3=NULL;
2427   MPI_Status     recv_status,*send_status;
2428   PetscInt       *sbuf_nz=NULL,*rbuf_nz=NULL,count;
2429   PetscInt       **rbuf_j=NULL;
2430   PetscScalar    **rbuf_a=NULL;
2431   Mat_Redundant  *redund =NULL;
2432 
2433   PetscFunctionBegin;
2434   ierr = PetscObjectGetComm((PetscObject)mat,&comm);CHKERRQ(ierr);
2435   ierr = MPI_Comm_rank(comm,&rank);CHKERRQ(ierr);
2436   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
2437   ierr = MPI_Comm_rank(subcomm,&subrank);CHKERRQ(ierr);
2438   ierr = MPI_Comm_size(subcomm,&subsize);CHKERRQ(ierr);
2439 
2440   if (reuse == MAT_REUSE_MATRIX) {
2441     if (M != mat->rmap->N || N != mat->cmap->N) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_SIZ,"Cannot reuse matrix. Wrong global size");
2442 
2443     redund = C->redundant;
2444     if (nzlocal != redund->nzlocal) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_SIZ,"Cannot reuse matrix. Wrong nzlocal");
2445 
2446     nsends    = redund->nsends;
2447     nrecvs    = redund->nrecvs;
2448     send_rank = redund->send_rank;
2449     recv_rank = redund->recv_rank;
2450     sbuf_nz   = redund->sbuf_nz;
2451     rbuf_nz   = redund->rbuf_nz;
2452     sbuf_j    = redund->sbuf_j;
2453     sbuf_a    = redund->sbuf_a;
2454     rbuf_j    = redund->rbuf_j;
2455     rbuf_a    = redund->rbuf_a;
2456   }
2457 
2458   if (reuse == MAT_INITIAL_MATRIX) {
2459     PetscInt    nleftover,np_subcomm;
2460 
2461     /* get the destination processors' id send_rank, nsends and nrecvs */
2462     ierr = PetscMalloc2(size,&send_rank,size,&recv_rank);CHKERRQ(ierr);
2463 
2464     np_subcomm = size/nsubcomm;
2465     nleftover  = size - nsubcomm*np_subcomm;
2466 
2467     /* block of codes below is specific for INTERLACED */
2468     /* ------------------------------------------------*/
2469     nsends = 0; nrecvs = 0;
2470     for (i=0; i<size; i++) {
2471       if (subrank == i/nsubcomm && i != rank) { /* my_subrank == other's subrank */
2472         send_rank[nsends++] = i;
2473         recv_rank[nrecvs++] = i;
2474       }
2475     }
2476     if (rank >= size - nleftover) { /* this proc is a leftover processor */
2477       i = size-nleftover-1;
2478       j = 0;
2479       while (j < nsubcomm - nleftover) {
2480         send_rank[nsends++] = i;
2481         i--; j++;
2482       }
2483     }
2484 
2485     if (nleftover && subsize == size/nsubcomm && subrank==subsize-1) { /* this proc recvs from leftover processors */
2486       for (i=0; i<nleftover; i++) {
2487         recv_rank[nrecvs++] = size-nleftover+i;
2488       }
2489     }
2490     /*----------------------------------------------*/
2491 
2492     /* allocate sbuf_j, sbuf_a */
2493     i    = nzlocal + rowrange[rank+1] - rowrange[rank] + 2;
2494     ierr = PetscMalloc1(i,&sbuf_j);CHKERRQ(ierr);
2495     ierr = PetscMalloc1((nzlocal+1),&sbuf_a);CHKERRQ(ierr);
2496     /*
2497     ierr = PetscSynchronizedPrintf(comm,"[%d] nsends %d, nrecvs %d\n",rank,nsends,nrecvs);CHKERRQ(ierr);
2498     ierr = PetscSynchronizedFlush(comm,PETSC_STDOUT);CHKERRQ(ierr);
2499      */
2500   } /* endof if (reuse == MAT_INITIAL_MATRIX) */
2501 
2502   /* copy mat's local entries into the buffers */
2503   if (reuse == MAT_INITIAL_MATRIX) {
2504     rownz_max = 0;
2505     rptr      = sbuf_j;
2506     cols      = sbuf_j + rend-rstart + 1;
2507     vals      = sbuf_a;
2508     rptr[0]   = 0;
2509     for (i=0; i<rend-rstart; i++) {
2510       row    = i + rstart;
2511       nzA    = a->i[i+1] - a->i[i]; nzB = b->i[i+1] - b->i[i];
2512       ncols  = nzA + nzB;
2513       cworkA = a->j + a->i[i]; cworkB = b->j + b->i[i];
2514       aworkA = a->a + a->i[i]; aworkB = b->a + b->i[i];
2515       /* load the column indices for this row into cols */
2516       lwrite = 0;
2517       for (l=0; l<nzB; l++) {
2518         if ((ctmp = bmap[cworkB[l]]) < cstart) {
2519           vals[lwrite]   = aworkB[l];
2520           cols[lwrite++] = ctmp;
2521         }
2522       }
2523       for (l=0; l<nzA; l++) {
2524         vals[lwrite]   = aworkA[l];
2525         cols[lwrite++] = cstart + cworkA[l];
2526       }
2527       for (l=0; l<nzB; l++) {
2528         if ((ctmp = bmap[cworkB[l]]) >= cend) {
2529           vals[lwrite]   = aworkB[l];
2530           cols[lwrite++] = ctmp;
2531         }
2532       }
2533       vals     += ncols;
2534       cols     += ncols;
2535       rptr[i+1] = rptr[i] + ncols;
2536       if (rownz_max < ncols) rownz_max = ncols;
2537     }
2538     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);
2539   } else { /* only copy matrix values into sbuf_a */
2540     rptr    = sbuf_j;
2541     vals    = sbuf_a;
2542     rptr[0] = 0;
2543     for (i=0; i<rend-rstart; i++) {
2544       row    = i + rstart;
2545       nzA    = a->i[i+1] - a->i[i]; nzB = b->i[i+1] - b->i[i];
2546       ncols  = nzA + nzB;
2547       cworkB = b->j + b->i[i];
2548       aworkA = a->a + a->i[i];
2549       aworkB = b->a + b->i[i];
2550       lwrite = 0;
2551       for (l=0; l<nzB; l++) {
2552         if ((ctmp = bmap[cworkB[l]]) < cstart) vals[lwrite++] = aworkB[l];
2553       }
2554       for (l=0; l<nzA; l++) vals[lwrite++] = aworkA[l];
2555       for (l=0; l<nzB; l++) {
2556         if ((ctmp = bmap[cworkB[l]]) >= cend) vals[lwrite++] = aworkB[l];
2557       }
2558       vals     += ncols;
2559       rptr[i+1] = rptr[i] + ncols;
2560     }
2561   } /* endof if (reuse == MAT_INITIAL_MATRIX) */
2562 
2563   /* send nzlocal to others, and recv other's nzlocal */
2564   /*--------------------------------------------------*/
2565   if (reuse == MAT_INITIAL_MATRIX) {
2566     ierr = PetscMalloc2(3*(nsends + nrecvs)+1,&s_waits3,nsends+1,&send_status);CHKERRQ(ierr);
2567 
2568     s_waits2 = s_waits3 + nsends;
2569     s_waits1 = s_waits2 + nsends;
2570     r_waits1 = s_waits1 + nsends;
2571     r_waits2 = r_waits1 + nrecvs;
2572     r_waits3 = r_waits2 + nrecvs;
2573   } else {
2574     ierr = PetscMalloc2(nsends + nrecvs +1,&s_waits3,nsends+1,&send_status);CHKERRQ(ierr);
2575 
2576     r_waits3 = s_waits3 + nsends;
2577   }
2578 
2579   ierr = PetscObjectGetNewTag((PetscObject)mat,&tag3);CHKERRQ(ierr);
2580   if (reuse == MAT_INITIAL_MATRIX) {
2581     /* get new tags to keep the communication clean */
2582     ierr = PetscObjectGetNewTag((PetscObject)mat,&tag1);CHKERRQ(ierr);
2583     ierr = PetscObjectGetNewTag((PetscObject)mat,&tag2);CHKERRQ(ierr);
2584     ierr = PetscMalloc4(nsends,&sbuf_nz,nrecvs,&rbuf_nz,nrecvs,&rbuf_j,nrecvs,&rbuf_a);CHKERRQ(ierr);
2585 
2586     /* post receives of other's nzlocal */
2587     for (i=0; i<nrecvs; i++) {
2588       ierr = MPI_Irecv(rbuf_nz+i,1,MPIU_INT,MPI_ANY_SOURCE,tag1,comm,r_waits1+i);CHKERRQ(ierr);
2589     }
2590     /* send nzlocal to others */
2591     for (i=0; i<nsends; i++) {
2592       sbuf_nz[i] = nzlocal;
2593       ierr       = MPI_Isend(sbuf_nz+i,1,MPIU_INT,send_rank[i],tag1,comm,s_waits1+i);CHKERRQ(ierr);
2594     }
2595     /* wait on receives of nzlocal; allocate space for rbuf_j, rbuf_a */
2596     count = nrecvs;
2597     while (count) {
2598       ierr = MPI_Waitany(nrecvs,r_waits1,&imdex,&recv_status);CHKERRQ(ierr);
2599 
2600       recv_rank[imdex] = recv_status.MPI_SOURCE;
2601       /* allocate rbuf_a and rbuf_j; then post receives of rbuf_j */
2602       ierr = PetscMalloc1((rbuf_nz[imdex]+1),&rbuf_a[imdex]);CHKERRQ(ierr);
2603 
2604       i = rowrange[recv_status.MPI_SOURCE+1] - rowrange[recv_status.MPI_SOURCE]; /* number of expected mat->i */
2605 
2606       rbuf_nz[imdex] += i + 2;
2607 
2608       ierr = PetscMalloc1(rbuf_nz[imdex],&rbuf_j[imdex]);CHKERRQ(ierr);
2609       ierr = MPI_Irecv(rbuf_j[imdex],rbuf_nz[imdex],MPIU_INT,recv_status.MPI_SOURCE,tag2,comm,r_waits2+imdex);CHKERRQ(ierr);
2610       count--;
2611     }
2612     /* wait on sends of nzlocal */
2613     if (nsends) {ierr = MPI_Waitall(nsends,s_waits1,send_status);CHKERRQ(ierr);}
2614     /* send mat->i,j to others, and recv from other's */
2615     /*------------------------------------------------*/
2616     for (i=0; i<nsends; i++) {
2617       j    = nzlocal + rowrange[rank+1] - rowrange[rank] + 1;
2618       ierr = MPI_Isend(sbuf_j,j,MPIU_INT,send_rank[i],tag2,comm,s_waits2+i);CHKERRQ(ierr);
2619     }
2620     /* wait on receives of mat->i,j */
2621     /*------------------------------*/
2622     count = nrecvs;
2623     while (count) {
2624       ierr = MPI_Waitany(nrecvs,r_waits2,&imdex,&recv_status);CHKERRQ(ierr);
2625       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);
2626       count--;
2627     }
2628     /* wait on sends of mat->i,j */
2629     /*---------------------------*/
2630     if (nsends) {
2631       ierr = MPI_Waitall(nsends,s_waits2,send_status);CHKERRQ(ierr);
2632     }
2633   } /* endof if (reuse == MAT_INITIAL_MATRIX) */
2634 
2635   /* post receives, send and receive mat->a */
2636   /*----------------------------------------*/
2637   for (imdex=0; imdex<nrecvs; imdex++) {
2638     ierr = MPI_Irecv(rbuf_a[imdex],rbuf_nz[imdex],MPIU_SCALAR,recv_rank[imdex],tag3,comm,r_waits3+imdex);CHKERRQ(ierr);
2639   }
2640   for (i=0; i<nsends; i++) {
2641     ierr = MPI_Isend(sbuf_a,nzlocal,MPIU_SCALAR,send_rank[i],tag3,comm,s_waits3+i);CHKERRQ(ierr);
2642   }
2643   count = nrecvs;
2644   while (count) {
2645     ierr = MPI_Waitany(nrecvs,r_waits3,&imdex,&recv_status);CHKERRQ(ierr);
2646     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);
2647     count--;
2648   }
2649   if (nsends) {
2650     ierr = MPI_Waitall(nsends,s_waits3,send_status);CHKERRQ(ierr);
2651   }
2652 
2653   ierr = PetscFree2(s_waits3,send_status);CHKERRQ(ierr);
2654 
2655   /* create redundant matrix */
2656   /*-------------------------*/
2657   if (reuse == MAT_INITIAL_MATRIX) {
2658     const PetscInt *range;
2659     PetscInt       rstart_sub,rend_sub,mloc_sub;
2660 
2661     /* compute rownz_max for preallocation */
2662     for (imdex=0; imdex<nrecvs; imdex++) {
2663       j    = rowrange[recv_rank[imdex]+1] - rowrange[recv_rank[imdex]];
2664       rptr = rbuf_j[imdex];
2665       for (i=0; i<j; i++) {
2666         ncols = rptr[i+1] - rptr[i];
2667         if (rownz_max < ncols) rownz_max = ncols;
2668       }
2669     }
2670 
2671     ierr = MatCreate(subcomm,&C);CHKERRQ(ierr);
2672 
2673     /* get local size of redundant matrix
2674        - mloc_sub is chosen for PETSC_SUBCOMM_INTERLACED, works for other types, but may not efficient! */
2675     ierr = MatGetOwnershipRanges(mat,&range);CHKERRQ(ierr);
2676     rstart_sub = range[nsubcomm*subrank];
2677     if (subrank+1 < subsize) { /* not the last proc in subcomm */
2678       rend_sub = range[nsubcomm*(subrank+1)];
2679     } else {
2680       rend_sub = mat->rmap->N;
2681     }
2682     mloc_sub = rend_sub - rstart_sub;
2683 
2684     if (M == N) {
2685       ierr = MatSetSizes(C,mloc_sub,mloc_sub,PETSC_DECIDE,PETSC_DECIDE);CHKERRQ(ierr);
2686     } else { /* non-square matrix */
2687       ierr = MatSetSizes(C,mloc_sub,PETSC_DECIDE,PETSC_DECIDE,mat->cmap->N);CHKERRQ(ierr);
2688     }
2689     ierr = MatSetBlockSizesFromMats(C,mat,mat);CHKERRQ(ierr);
2690     ierr = MatSetFromOptions(C);CHKERRQ(ierr);
2691     ierr = MatSeqAIJSetPreallocation(C,rownz_max,NULL);CHKERRQ(ierr);
2692     ierr = MatMPIAIJSetPreallocation(C,rownz_max,NULL,rownz_max,NULL);CHKERRQ(ierr);
2693   } else {
2694     C = *matredundant;
2695   }
2696 
2697   /* insert local matrix entries */
2698   rptr = sbuf_j;
2699   cols = sbuf_j + rend-rstart + 1;
2700   vals = sbuf_a;
2701   for (i=0; i<rend-rstart; i++) {
2702     row   = i + rstart;
2703     ncols = rptr[i+1] - rptr[i];
2704     ierr  = MatSetValues(C,1,&row,ncols,cols,vals,INSERT_VALUES);CHKERRQ(ierr);
2705     vals += ncols;
2706     cols += ncols;
2707   }
2708   /* insert received matrix entries */
2709   for (imdex=0; imdex<nrecvs; imdex++) {
2710     rstart = rowrange[recv_rank[imdex]];
2711     rend   = rowrange[recv_rank[imdex]+1];
2712     /* printf("[%d] insert rows %d - %d\n",rank,rstart,rend-1); */
2713     rptr   = rbuf_j[imdex];
2714     cols   = rbuf_j[imdex] + rend-rstart + 1;
2715     vals   = rbuf_a[imdex];
2716     for (i=0; i<rend-rstart; i++) {
2717       row   = i + rstart;
2718       ncols = rptr[i+1] - rptr[i];
2719       ierr  = MatSetValues(C,1,&row,ncols,cols,vals,INSERT_VALUES);CHKERRQ(ierr);
2720       vals += ncols;
2721       cols += ncols;
2722     }
2723   }
2724   ierr = MatAssemblyBegin(C,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
2725   ierr = MatAssemblyEnd(C,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
2726 
2727   if (reuse == MAT_INITIAL_MATRIX) {
2728     *matredundant = C;
2729 
2730     /* create a supporting struct and attach it to C for reuse */
2731     ierr = PetscNewLog(C,&redund);CHKERRQ(ierr);
2732     C->redundant      = redund;
2733     redund->nzlocal   = nzlocal;
2734     redund->nsends    = nsends;
2735     redund->nrecvs    = nrecvs;
2736     redund->send_rank = send_rank;
2737     redund->recv_rank = recv_rank;
2738     redund->sbuf_nz   = sbuf_nz;
2739     redund->rbuf_nz   = rbuf_nz;
2740     redund->sbuf_j    = sbuf_j;
2741     redund->sbuf_a    = sbuf_a;
2742     redund->rbuf_j    = rbuf_j;
2743     redund->rbuf_a    = rbuf_a;
2744     redund->psubcomm  = NULL;
2745   }
2746   PetscFunctionReturn(0);
2747 }
2748 
2749 #undef __FUNCT__
2750 #define __FUNCT__ "MatGetRedundantMatrix_MPIAIJ"
2751 PetscErrorCode MatGetRedundantMatrix_MPIAIJ(Mat mat,PetscInt nsubcomm,MPI_Comm subcomm,MatReuse reuse,Mat *matredundant)
2752 {
2753   PetscErrorCode ierr;
2754   MPI_Comm       comm;
2755   PetscMPIInt    size,subsize;
2756   PetscInt       mloc_sub,rstart,rend,M=mat->rmap->N,N=mat->cmap->N;
2757   Mat_Redundant  *redund=NULL;
2758   PetscSubcomm   psubcomm=NULL;
2759   MPI_Comm       subcomm_in=subcomm;
2760   Mat            *matseq;
2761   IS             isrow,iscol;
2762 
2763   PetscFunctionBegin;
2764   if (subcomm_in == MPI_COMM_NULL) { /* user does not provide subcomm */
2765     if (reuse ==  MAT_INITIAL_MATRIX) {
2766       /* create psubcomm, then get subcomm */
2767       ierr = PetscObjectGetComm((PetscObject)mat,&comm);CHKERRQ(ierr);
2768       ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
2769       if (nsubcomm < 1 || nsubcomm > size) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_SIZ,"nsubcomm must between 1 and %D",size);
2770 
2771       ierr = PetscSubcommCreate(comm,&psubcomm);CHKERRQ(ierr);
2772       ierr = PetscSubcommSetNumber(psubcomm,nsubcomm);CHKERRQ(ierr);
2773       ierr = PetscSubcommSetType(psubcomm,PETSC_SUBCOMM_CONTIGUOUS);CHKERRQ(ierr);
2774       ierr = PetscSubcommSetFromOptions(psubcomm);CHKERRQ(ierr);
2775       subcomm = psubcomm->comm;
2776     } else { /* retrieve psubcomm and subcomm */
2777       ierr = PetscObjectGetComm((PetscObject)(*matredundant),&subcomm);CHKERRQ(ierr);
2778       ierr = MPI_Comm_size(subcomm,&subsize);CHKERRQ(ierr);
2779       redund   = (*matredundant)->redundant;
2780       psubcomm = redund->psubcomm;
2781     }
2782     if (psubcomm->type == PETSC_SUBCOMM_INTERLACED) {
2783       ierr = MatGetRedundantMatrix_MPIAIJ_interlaced(mat,nsubcomm,subcomm,reuse,matredundant);CHKERRQ(ierr);
2784       if (reuse ==  MAT_INITIAL_MATRIX) { /* psubcomm is created in this routine, free it in MatDestroy_Redundant() */
2785         ierr = MPI_Comm_size(psubcomm->comm,&subsize);CHKERRQ(ierr);
2786         (*matredundant)->redundant->psubcomm = psubcomm;
2787       }
2788       PetscFunctionReturn(0);
2789     }
2790   }
2791 
2792   /* use MPI subcomm via MatGetSubMatrices(); use subcomm_in or psubcomm->comm (psubcomm->type != INTERLACED) */
2793   ierr = MPI_Comm_size(subcomm,&subsize);CHKERRQ(ierr);
2794   if (reuse == MAT_INITIAL_MATRIX) {
2795     /* create a local sequential matrix matseq[0] */
2796     mloc_sub = PETSC_DECIDE;
2797     ierr = PetscSplitOwnership(subcomm,&mloc_sub,&M);CHKERRQ(ierr);
2798     ierr = MPI_Scan(&mloc_sub,&rend,1,MPIU_INT,MPI_SUM,subcomm);CHKERRQ(ierr);
2799     rstart = rend - mloc_sub;
2800     ierr = ISCreateStride(PETSC_COMM_SELF,mloc_sub,rstart,1,&isrow);CHKERRQ(ierr);
2801     ierr = ISCreateStride(PETSC_COMM_SELF,N,0,1,&iscol);CHKERRQ(ierr);
2802   } else { /* reuse == MAT_REUSE_MATRIX */
2803     redund = (*matredundant)->redundant;
2804     isrow  = redund->isrow;
2805     iscol  = redund->iscol;
2806     matseq = redund->matseq;
2807   }
2808   ierr = MatGetSubMatrices(mat,1,&isrow,&iscol,reuse,&matseq);CHKERRQ(ierr);
2809   ierr = MatCreateMPIMatConcatenateSeqMat(subcomm,matseq[0],PETSC_DECIDE,reuse,matredundant);CHKERRQ(ierr);
2810 
2811   if (reuse == MAT_INITIAL_MATRIX) {
2812     /* create a supporting struct and attach it to C for reuse */
2813     ierr = PetscNewLog(*matredundant,&redund);CHKERRQ(ierr);
2814     (*matredundant)->redundant = redund;
2815     redund->isrow              = isrow;
2816     redund->iscol              = iscol;
2817     redund->matseq             = matseq;
2818     redund->psubcomm           = psubcomm;
2819   }
2820   PetscFunctionReturn(0);
2821 }
2822 
2823 #undef __FUNCT__
2824 #define __FUNCT__ "MatGetRowMaxAbs_MPIAIJ"
2825 PetscErrorCode MatGetRowMaxAbs_MPIAIJ(Mat A, Vec v, PetscInt idx[])
2826 {
2827   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
2828   PetscErrorCode ierr;
2829   PetscInt       i,*idxb = 0;
2830   PetscScalar    *va,*vb;
2831   Vec            vtmp;
2832 
2833   PetscFunctionBegin;
2834   ierr = MatGetRowMaxAbs(a->A,v,idx);CHKERRQ(ierr);
2835   ierr = VecGetArray(v,&va);CHKERRQ(ierr);
2836   if (idx) {
2837     for (i=0; i<A->rmap->n; i++) {
2838       if (PetscAbsScalar(va[i])) idx[i] += A->cmap->rstart;
2839     }
2840   }
2841 
2842   ierr = VecCreateSeq(PETSC_COMM_SELF,A->rmap->n,&vtmp);CHKERRQ(ierr);
2843   if (idx) {
2844     ierr = PetscMalloc1(A->rmap->n,&idxb);CHKERRQ(ierr);
2845   }
2846   ierr = MatGetRowMaxAbs(a->B,vtmp,idxb);CHKERRQ(ierr);
2847   ierr = VecGetArray(vtmp,&vb);CHKERRQ(ierr);
2848 
2849   for (i=0; i<A->rmap->n; i++) {
2850     if (PetscAbsScalar(va[i]) < PetscAbsScalar(vb[i])) {
2851       va[i] = vb[i];
2852       if (idx) idx[i] = a->garray[idxb[i]];
2853     }
2854   }
2855 
2856   ierr = VecRestoreArray(v,&va);CHKERRQ(ierr);
2857   ierr = VecRestoreArray(vtmp,&vb);CHKERRQ(ierr);
2858   ierr = PetscFree(idxb);CHKERRQ(ierr);
2859   ierr = VecDestroy(&vtmp);CHKERRQ(ierr);
2860   PetscFunctionReturn(0);
2861 }
2862 
2863 #undef __FUNCT__
2864 #define __FUNCT__ "MatGetRowMinAbs_MPIAIJ"
2865 PetscErrorCode MatGetRowMinAbs_MPIAIJ(Mat A, Vec v, PetscInt idx[])
2866 {
2867   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
2868   PetscErrorCode ierr;
2869   PetscInt       i,*idxb = 0;
2870   PetscScalar    *va,*vb;
2871   Vec            vtmp;
2872 
2873   PetscFunctionBegin;
2874   ierr = MatGetRowMinAbs(a->A,v,idx);CHKERRQ(ierr);
2875   ierr = VecGetArray(v,&va);CHKERRQ(ierr);
2876   if (idx) {
2877     for (i=0; i<A->cmap->n; i++) {
2878       if (PetscAbsScalar(va[i])) idx[i] += A->cmap->rstart;
2879     }
2880   }
2881 
2882   ierr = VecCreateSeq(PETSC_COMM_SELF,A->rmap->n,&vtmp);CHKERRQ(ierr);
2883   if (idx) {
2884     ierr = PetscMalloc1(A->rmap->n,&idxb);CHKERRQ(ierr);
2885   }
2886   ierr = MatGetRowMinAbs(a->B,vtmp,idxb);CHKERRQ(ierr);
2887   ierr = VecGetArray(vtmp,&vb);CHKERRQ(ierr);
2888 
2889   for (i=0; i<A->rmap->n; i++) {
2890     if (PetscAbsScalar(va[i]) > PetscAbsScalar(vb[i])) {
2891       va[i] = vb[i];
2892       if (idx) idx[i] = a->garray[idxb[i]];
2893     }
2894   }
2895 
2896   ierr = VecRestoreArray(v,&va);CHKERRQ(ierr);
2897   ierr = VecRestoreArray(vtmp,&vb);CHKERRQ(ierr);
2898   ierr = PetscFree(idxb);CHKERRQ(ierr);
2899   ierr = VecDestroy(&vtmp);CHKERRQ(ierr);
2900   PetscFunctionReturn(0);
2901 }
2902 
2903 #undef __FUNCT__
2904 #define __FUNCT__ "MatGetRowMin_MPIAIJ"
2905 PetscErrorCode MatGetRowMin_MPIAIJ(Mat A, Vec v, PetscInt idx[])
2906 {
2907   Mat_MPIAIJ     *mat   = (Mat_MPIAIJ*) A->data;
2908   PetscInt       n      = A->rmap->n;
2909   PetscInt       cstart = A->cmap->rstart;
2910   PetscInt       *cmap  = mat->garray;
2911   PetscInt       *diagIdx, *offdiagIdx;
2912   Vec            diagV, offdiagV;
2913   PetscScalar    *a, *diagA, *offdiagA;
2914   PetscInt       r;
2915   PetscErrorCode ierr;
2916 
2917   PetscFunctionBegin;
2918   ierr = PetscMalloc2(n,&diagIdx,n,&offdiagIdx);CHKERRQ(ierr);
2919   ierr = VecCreateSeq(PetscObjectComm((PetscObject)A), n, &diagV);CHKERRQ(ierr);
2920   ierr = VecCreateSeq(PetscObjectComm((PetscObject)A), n, &offdiagV);CHKERRQ(ierr);
2921   ierr = MatGetRowMin(mat->A, diagV,    diagIdx);CHKERRQ(ierr);
2922   ierr = MatGetRowMin(mat->B, offdiagV, offdiagIdx);CHKERRQ(ierr);
2923   ierr = VecGetArray(v,        &a);CHKERRQ(ierr);
2924   ierr = VecGetArray(diagV,    &diagA);CHKERRQ(ierr);
2925   ierr = VecGetArray(offdiagV, &offdiagA);CHKERRQ(ierr);
2926   for (r = 0; r < n; ++r) {
2927     if (PetscAbsScalar(diagA[r]) <= PetscAbsScalar(offdiagA[r])) {
2928       a[r]   = diagA[r];
2929       idx[r] = cstart + diagIdx[r];
2930     } else {
2931       a[r]   = offdiagA[r];
2932       idx[r] = cmap[offdiagIdx[r]];
2933     }
2934   }
2935   ierr = VecRestoreArray(v,        &a);CHKERRQ(ierr);
2936   ierr = VecRestoreArray(diagV,    &diagA);CHKERRQ(ierr);
2937   ierr = VecRestoreArray(offdiagV, &offdiagA);CHKERRQ(ierr);
2938   ierr = VecDestroy(&diagV);CHKERRQ(ierr);
2939   ierr = VecDestroy(&offdiagV);CHKERRQ(ierr);
2940   ierr = PetscFree2(diagIdx, offdiagIdx);CHKERRQ(ierr);
2941   PetscFunctionReturn(0);
2942 }
2943 
2944 #undef __FUNCT__
2945 #define __FUNCT__ "MatGetRowMax_MPIAIJ"
2946 PetscErrorCode MatGetRowMax_MPIAIJ(Mat A, Vec v, PetscInt idx[])
2947 {
2948   Mat_MPIAIJ     *mat   = (Mat_MPIAIJ*) A->data;
2949   PetscInt       n      = A->rmap->n;
2950   PetscInt       cstart = A->cmap->rstart;
2951   PetscInt       *cmap  = mat->garray;
2952   PetscInt       *diagIdx, *offdiagIdx;
2953   Vec            diagV, offdiagV;
2954   PetscScalar    *a, *diagA, *offdiagA;
2955   PetscInt       r;
2956   PetscErrorCode ierr;
2957 
2958   PetscFunctionBegin;
2959   ierr = PetscMalloc2(n,&diagIdx,n,&offdiagIdx);CHKERRQ(ierr);
2960   ierr = VecCreateSeq(PETSC_COMM_SELF, n, &diagV);CHKERRQ(ierr);
2961   ierr = VecCreateSeq(PETSC_COMM_SELF, n, &offdiagV);CHKERRQ(ierr);
2962   ierr = MatGetRowMax(mat->A, diagV,    diagIdx);CHKERRQ(ierr);
2963   ierr = MatGetRowMax(mat->B, offdiagV, offdiagIdx);CHKERRQ(ierr);
2964   ierr = VecGetArray(v,        &a);CHKERRQ(ierr);
2965   ierr = VecGetArray(diagV,    &diagA);CHKERRQ(ierr);
2966   ierr = VecGetArray(offdiagV, &offdiagA);CHKERRQ(ierr);
2967   for (r = 0; r < n; ++r) {
2968     if (PetscAbsScalar(diagA[r]) >= PetscAbsScalar(offdiagA[r])) {
2969       a[r]   = diagA[r];
2970       idx[r] = cstart + diagIdx[r];
2971     } else {
2972       a[r]   = offdiagA[r];
2973       idx[r] = cmap[offdiagIdx[r]];
2974     }
2975   }
2976   ierr = VecRestoreArray(v,        &a);CHKERRQ(ierr);
2977   ierr = VecRestoreArray(diagV,    &diagA);CHKERRQ(ierr);
2978   ierr = VecRestoreArray(offdiagV, &offdiagA);CHKERRQ(ierr);
2979   ierr = VecDestroy(&diagV);CHKERRQ(ierr);
2980   ierr = VecDestroy(&offdiagV);CHKERRQ(ierr);
2981   ierr = PetscFree2(diagIdx, offdiagIdx);CHKERRQ(ierr);
2982   PetscFunctionReturn(0);
2983 }
2984 
2985 #undef __FUNCT__
2986 #define __FUNCT__ "MatGetSeqNonzeroStructure_MPIAIJ"
2987 PetscErrorCode MatGetSeqNonzeroStructure_MPIAIJ(Mat mat,Mat *newmat)
2988 {
2989   PetscErrorCode ierr;
2990   Mat            *dummy;
2991 
2992   PetscFunctionBegin;
2993   ierr    = MatGetSubMatrix_MPIAIJ_All(mat,MAT_DO_NOT_GET_VALUES,MAT_INITIAL_MATRIX,&dummy);CHKERRQ(ierr);
2994   *newmat = *dummy;
2995   ierr    = PetscFree(dummy);CHKERRQ(ierr);
2996   PetscFunctionReturn(0);
2997 }
2998 
2999 #undef __FUNCT__
3000 #define __FUNCT__ "MatInvertBlockDiagonal_MPIAIJ"
3001 PetscErrorCode  MatInvertBlockDiagonal_MPIAIJ(Mat A,const PetscScalar **values)
3002 {
3003   Mat_MPIAIJ     *a = (Mat_MPIAIJ*) A->data;
3004   PetscErrorCode ierr;
3005 
3006   PetscFunctionBegin;
3007   ierr = MatInvertBlockDiagonal(a->A,values);CHKERRQ(ierr);
3008   PetscFunctionReturn(0);
3009 }
3010 
3011 #undef __FUNCT__
3012 #define __FUNCT__ "MatSetRandom_MPIAIJ"
3013 static PetscErrorCode  MatSetRandom_MPIAIJ(Mat x,PetscRandom rctx)
3014 {
3015   PetscErrorCode ierr;
3016   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)x->data;
3017 
3018   PetscFunctionBegin;
3019   ierr = MatSetRandom(aij->A,rctx);CHKERRQ(ierr);
3020   ierr = MatSetRandom(aij->B,rctx);CHKERRQ(ierr);
3021   ierr = MatAssemblyBegin(x,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
3022   ierr = MatAssemblyEnd(x,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
3023   PetscFunctionReturn(0);
3024 }
3025 
3026 /* -------------------------------------------------------------------*/
3027 static struct _MatOps MatOps_Values = {MatSetValues_MPIAIJ,
3028                                        MatGetRow_MPIAIJ,
3029                                        MatRestoreRow_MPIAIJ,
3030                                        MatMult_MPIAIJ,
3031                                 /* 4*/ MatMultAdd_MPIAIJ,
3032                                        MatMultTranspose_MPIAIJ,
3033                                        MatMultTransposeAdd_MPIAIJ,
3034 #if defined(PETSC_HAVE_PBGL)
3035                                        MatSolve_MPIAIJ,
3036 #else
3037                                        0,
3038 #endif
3039                                        0,
3040                                        0,
3041                                 /*10*/ 0,
3042                                        0,
3043                                        0,
3044                                        MatSOR_MPIAIJ,
3045                                        MatTranspose_MPIAIJ,
3046                                 /*15*/ MatGetInfo_MPIAIJ,
3047                                        MatEqual_MPIAIJ,
3048                                        MatGetDiagonal_MPIAIJ,
3049                                        MatDiagonalScale_MPIAIJ,
3050                                        MatNorm_MPIAIJ,
3051                                 /*20*/ MatAssemblyBegin_MPIAIJ,
3052                                        MatAssemblyEnd_MPIAIJ,
3053                                        MatSetOption_MPIAIJ,
3054                                        MatZeroEntries_MPIAIJ,
3055                                 /*24*/ MatZeroRows_MPIAIJ,
3056                                        0,
3057 #if defined(PETSC_HAVE_PBGL)
3058                                        0,
3059 #else
3060                                        0,
3061 #endif
3062                                        0,
3063                                        0,
3064                                 /*29*/ MatSetUp_MPIAIJ,
3065 #if defined(PETSC_HAVE_PBGL)
3066                                        0,
3067 #else
3068                                        0,
3069 #endif
3070                                        0,
3071                                        0,
3072                                        0,
3073                                 /*34*/ MatDuplicate_MPIAIJ,
3074                                        0,
3075                                        0,
3076                                        0,
3077                                        0,
3078                                 /*39*/ MatAXPY_MPIAIJ,
3079                                        MatGetSubMatrices_MPIAIJ,
3080                                        MatIncreaseOverlap_MPIAIJ,
3081                                        MatGetValues_MPIAIJ,
3082                                        MatCopy_MPIAIJ,
3083                                 /*44*/ MatGetRowMax_MPIAIJ,
3084                                        MatScale_MPIAIJ,
3085                                        0,
3086                                        MatDiagonalSet_MPIAIJ,
3087                                        MatZeroRowsColumns_MPIAIJ,
3088                                 /*49*/ MatSetRandom_MPIAIJ,
3089                                        0,
3090                                        0,
3091                                        0,
3092                                        0,
3093                                 /*54*/ MatFDColoringCreate_MPIXAIJ,
3094                                        0,
3095                                        MatSetUnfactored_MPIAIJ,
3096                                        MatPermute_MPIAIJ,
3097                                        0,
3098                                 /*59*/ MatGetSubMatrix_MPIAIJ,
3099                                        MatDestroy_MPIAIJ,
3100                                        MatView_MPIAIJ,
3101                                        0,
3102                                        MatMatMatMult_MPIAIJ_MPIAIJ_MPIAIJ,
3103                                 /*64*/ MatMatMatMultSymbolic_MPIAIJ_MPIAIJ_MPIAIJ,
3104                                        MatMatMatMultNumeric_MPIAIJ_MPIAIJ_MPIAIJ,
3105                                        0,
3106                                        0,
3107                                        0,
3108                                 /*69*/ MatGetRowMaxAbs_MPIAIJ,
3109                                        MatGetRowMinAbs_MPIAIJ,
3110                                        0,
3111                                        MatSetColoring_MPIAIJ,
3112                                        0,
3113                                        MatSetValuesAdifor_MPIAIJ,
3114                                 /*75*/ MatFDColoringApply_AIJ,
3115                                        0,
3116                                        0,
3117                                        0,
3118                                        MatFindZeroDiagonals_MPIAIJ,
3119                                 /*80*/ 0,
3120                                        0,
3121                                        0,
3122                                 /*83*/ MatLoad_MPIAIJ,
3123                                        0,
3124                                        0,
3125                                        0,
3126                                        0,
3127                                        0,
3128                                 /*89*/ MatMatMult_MPIAIJ_MPIAIJ,
3129                                        MatMatMultSymbolic_MPIAIJ_MPIAIJ,
3130                                        MatMatMultNumeric_MPIAIJ_MPIAIJ,
3131                                        MatPtAP_MPIAIJ_MPIAIJ,
3132                                        MatPtAPSymbolic_MPIAIJ_MPIAIJ,
3133                                 /*94*/ MatPtAPNumeric_MPIAIJ_MPIAIJ,
3134                                        0,
3135                                        0,
3136                                        0,
3137                                        0,
3138                                 /*99*/ 0,
3139                                        0,
3140                                        0,
3141                                        MatConjugate_MPIAIJ,
3142                                        0,
3143                                 /*104*/MatSetValuesRow_MPIAIJ,
3144                                        MatRealPart_MPIAIJ,
3145                                        MatImaginaryPart_MPIAIJ,
3146                                        0,
3147                                        0,
3148                                 /*109*/0,
3149                                        MatGetRedundantMatrix_MPIAIJ,
3150                                        MatGetRowMin_MPIAIJ,
3151                                        0,
3152                                        0,
3153                                 /*114*/MatGetSeqNonzeroStructure_MPIAIJ,
3154                                        0,
3155                                        0,
3156                                        0,
3157                                        0,
3158                                 /*119*/0,
3159                                        0,
3160                                        0,
3161                                        0,
3162                                        MatGetMultiProcBlock_MPIAIJ,
3163                                 /*124*/MatFindNonzeroRows_MPIAIJ,
3164                                        MatGetColumnNorms_MPIAIJ,
3165                                        MatInvertBlockDiagonal_MPIAIJ,
3166                                        0,
3167                                        MatGetSubMatricesParallel_MPIAIJ,
3168                                 /*129*/0,
3169                                        MatTransposeMatMult_MPIAIJ_MPIAIJ,
3170                                        MatTransposeMatMultSymbolic_MPIAIJ_MPIAIJ,
3171                                        MatTransposeMatMultNumeric_MPIAIJ_MPIAIJ,
3172                                        0,
3173                                 /*134*/0,
3174                                        0,
3175                                        0,
3176                                        0,
3177                                        0,
3178                                 /*139*/0,
3179                                        0,
3180                                        0,
3181                                        MatFDColoringSetUp_MPIXAIJ,
3182                                        0,
3183                                 /*144*/MatCreateMPIMatConcatenateSeqMat_MPIAIJ
3184 };
3185 
3186 /* ----------------------------------------------------------------------------------------*/
3187 
3188 #undef __FUNCT__
3189 #define __FUNCT__ "MatStoreValues_MPIAIJ"
3190 PetscErrorCode  MatStoreValues_MPIAIJ(Mat mat)
3191 {
3192   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
3193   PetscErrorCode ierr;
3194 
3195   PetscFunctionBegin;
3196   ierr = MatStoreValues(aij->A);CHKERRQ(ierr);
3197   ierr = MatStoreValues(aij->B);CHKERRQ(ierr);
3198   PetscFunctionReturn(0);
3199 }
3200 
3201 #undef __FUNCT__
3202 #define __FUNCT__ "MatRetrieveValues_MPIAIJ"
3203 PetscErrorCode  MatRetrieveValues_MPIAIJ(Mat mat)
3204 {
3205   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
3206   PetscErrorCode ierr;
3207 
3208   PetscFunctionBegin;
3209   ierr = MatRetrieveValues(aij->A);CHKERRQ(ierr);
3210   ierr = MatRetrieveValues(aij->B);CHKERRQ(ierr);
3211   PetscFunctionReturn(0);
3212 }
3213 
3214 #undef __FUNCT__
3215 #define __FUNCT__ "MatMPIAIJSetPreallocation_MPIAIJ"
3216 PetscErrorCode  MatMPIAIJSetPreallocation_MPIAIJ(Mat B,PetscInt d_nz,const PetscInt d_nnz[],PetscInt o_nz,const PetscInt o_nnz[])
3217 {
3218   Mat_MPIAIJ     *b;
3219   PetscErrorCode ierr;
3220 
3221   PetscFunctionBegin;
3222   ierr = PetscLayoutSetUp(B->rmap);CHKERRQ(ierr);
3223   ierr = PetscLayoutSetUp(B->cmap);CHKERRQ(ierr);
3224   b = (Mat_MPIAIJ*)B->data;
3225 
3226   if (!B->preallocated) {
3227     /* Explicitly create 2 MATSEQAIJ matrices. */
3228     ierr = MatCreate(PETSC_COMM_SELF,&b->A);CHKERRQ(ierr);
3229     ierr = MatSetSizes(b->A,B->rmap->n,B->cmap->n,B->rmap->n,B->cmap->n);CHKERRQ(ierr);
3230     ierr = MatSetBlockSizesFromMats(b->A,B,B);CHKERRQ(ierr);
3231     ierr = MatSetType(b->A,MATSEQAIJ);CHKERRQ(ierr);
3232     ierr = PetscLogObjectParent((PetscObject)B,(PetscObject)b->A);CHKERRQ(ierr);
3233     ierr = MatCreate(PETSC_COMM_SELF,&b->B);CHKERRQ(ierr);
3234     ierr = MatSetSizes(b->B,B->rmap->n,B->cmap->N,B->rmap->n,B->cmap->N);CHKERRQ(ierr);
3235     ierr = MatSetBlockSizesFromMats(b->B,B,B);CHKERRQ(ierr);
3236     ierr = MatSetType(b->B,MATSEQAIJ);CHKERRQ(ierr);
3237     ierr = PetscLogObjectParent((PetscObject)B,(PetscObject)b->B);CHKERRQ(ierr);
3238   }
3239 
3240   ierr = MatSeqAIJSetPreallocation(b->A,d_nz,d_nnz);CHKERRQ(ierr);
3241   ierr = MatSeqAIJSetPreallocation(b->B,o_nz,o_nnz);CHKERRQ(ierr);
3242   B->preallocated = PETSC_TRUE;
3243   PetscFunctionReturn(0);
3244 }
3245 
3246 #undef __FUNCT__
3247 #define __FUNCT__ "MatDuplicate_MPIAIJ"
3248 PetscErrorCode MatDuplicate_MPIAIJ(Mat matin,MatDuplicateOption cpvalues,Mat *newmat)
3249 {
3250   Mat            mat;
3251   Mat_MPIAIJ     *a,*oldmat = (Mat_MPIAIJ*)matin->data;
3252   PetscErrorCode ierr;
3253 
3254   PetscFunctionBegin;
3255   *newmat = 0;
3256   ierr    = MatCreate(PetscObjectComm((PetscObject)matin),&mat);CHKERRQ(ierr);
3257   ierr    = MatSetSizes(mat,matin->rmap->n,matin->cmap->n,matin->rmap->N,matin->cmap->N);CHKERRQ(ierr);
3258   ierr    = MatSetBlockSizesFromMats(mat,matin,matin);CHKERRQ(ierr);
3259   ierr    = MatSetType(mat,((PetscObject)matin)->type_name);CHKERRQ(ierr);
3260   ierr    = PetscMemcpy(mat->ops,matin->ops,sizeof(struct _MatOps));CHKERRQ(ierr);
3261   a       = (Mat_MPIAIJ*)mat->data;
3262 
3263   mat->factortype   = matin->factortype;
3264   mat->assembled    = PETSC_TRUE;
3265   mat->insertmode   = NOT_SET_VALUES;
3266   mat->preallocated = PETSC_TRUE;
3267 
3268   a->size         = oldmat->size;
3269   a->rank         = oldmat->rank;
3270   a->donotstash   = oldmat->donotstash;
3271   a->roworiented  = oldmat->roworiented;
3272   a->rowindices   = 0;
3273   a->rowvalues    = 0;
3274   a->getrowactive = PETSC_FALSE;
3275 
3276   ierr = PetscLayoutReference(matin->rmap,&mat->rmap);CHKERRQ(ierr);
3277   ierr = PetscLayoutReference(matin->cmap,&mat->cmap);CHKERRQ(ierr);
3278 
3279   if (oldmat->colmap) {
3280 #if defined(PETSC_USE_CTABLE)
3281     ierr = PetscTableCreateCopy(oldmat->colmap,&a->colmap);CHKERRQ(ierr);
3282 #else
3283     ierr = PetscMalloc1((mat->cmap->N),&a->colmap);CHKERRQ(ierr);
3284     ierr = PetscLogObjectMemory((PetscObject)mat,(mat->cmap->N)*sizeof(PetscInt));CHKERRQ(ierr);
3285     ierr = PetscMemcpy(a->colmap,oldmat->colmap,(mat->cmap->N)*sizeof(PetscInt));CHKERRQ(ierr);
3286 #endif
3287   } else a->colmap = 0;
3288   if (oldmat->garray) {
3289     PetscInt len;
3290     len  = oldmat->B->cmap->n;
3291     ierr = PetscMalloc1((len+1),&a->garray);CHKERRQ(ierr);
3292     ierr = PetscLogObjectMemory((PetscObject)mat,len*sizeof(PetscInt));CHKERRQ(ierr);
3293     if (len) { ierr = PetscMemcpy(a->garray,oldmat->garray,len*sizeof(PetscInt));CHKERRQ(ierr); }
3294   } else a->garray = 0;
3295 
3296   ierr    = VecDuplicate(oldmat->lvec,&a->lvec);CHKERRQ(ierr);
3297   ierr    = PetscLogObjectParent((PetscObject)mat,(PetscObject)a->lvec);CHKERRQ(ierr);
3298   ierr    = VecScatterCopy(oldmat->Mvctx,&a->Mvctx);CHKERRQ(ierr);
3299   ierr    = PetscLogObjectParent((PetscObject)mat,(PetscObject)a->Mvctx);CHKERRQ(ierr);
3300   ierr    = MatDuplicate(oldmat->A,cpvalues,&a->A);CHKERRQ(ierr);
3301   ierr    = PetscLogObjectParent((PetscObject)mat,(PetscObject)a->A);CHKERRQ(ierr);
3302   ierr    = MatDuplicate(oldmat->B,cpvalues,&a->B);CHKERRQ(ierr);
3303   ierr    = PetscLogObjectParent((PetscObject)mat,(PetscObject)a->B);CHKERRQ(ierr);
3304   ierr    = PetscFunctionListDuplicate(((PetscObject)matin)->qlist,&((PetscObject)mat)->qlist);CHKERRQ(ierr);
3305   *newmat = mat;
3306   PetscFunctionReturn(0);
3307 }
3308 
3309 
3310 
3311 #undef __FUNCT__
3312 #define __FUNCT__ "MatLoad_MPIAIJ"
3313 PetscErrorCode MatLoad_MPIAIJ(Mat newMat, PetscViewer viewer)
3314 {
3315   PetscScalar    *vals,*svals;
3316   MPI_Comm       comm;
3317   PetscErrorCode ierr;
3318   PetscMPIInt    rank,size,tag = ((PetscObject)viewer)->tag;
3319   PetscInt       i,nz,j,rstart,rend,mmax,maxnz = 0,grows,gcols;
3320   PetscInt       header[4],*rowlengths = 0,M,N,m,*cols;
3321   PetscInt       *ourlens = NULL,*procsnz = NULL,*offlens = NULL,jj,*mycols,*smycols;
3322   PetscInt       cend,cstart,n,*rowners,sizesset=1;
3323   int            fd;
3324   PetscInt       bs = 1;
3325 
3326   PetscFunctionBegin;
3327   ierr = PetscObjectGetComm((PetscObject)viewer,&comm);CHKERRQ(ierr);
3328   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
3329   ierr = MPI_Comm_rank(comm,&rank);CHKERRQ(ierr);
3330   if (!rank) {
3331     ierr = PetscViewerBinaryGetDescriptor(viewer,&fd);CHKERRQ(ierr);
3332     ierr = PetscBinaryRead(fd,(char*)header,4,PETSC_INT);CHKERRQ(ierr);
3333     if (header[0] != MAT_FILE_CLASSID) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_FILE_UNEXPECTED,"not matrix object");
3334   }
3335 
3336   ierr = PetscOptionsBegin(comm,NULL,"Options for loading SEQAIJ matrix","Mat");CHKERRQ(ierr);
3337   ierr = PetscOptionsInt("-matload_block_size","Set the blocksize used to store the matrix","MatLoad",bs,&bs,NULL);CHKERRQ(ierr);
3338   ierr = PetscOptionsEnd();CHKERRQ(ierr);
3339 
3340   if (newMat->rmap->n < 0 && newMat->rmap->N < 0 && newMat->cmap->n < 0 && newMat->cmap->N < 0) sizesset = 0;
3341 
3342   ierr = MPI_Bcast(header+1,3,MPIU_INT,0,comm);CHKERRQ(ierr);
3343   M    = header[1]; N = header[2];
3344   /* If global rows/cols are set to PETSC_DECIDE, set it to the sizes given in the file */
3345   if (sizesset && newMat->rmap->N < 0) newMat->rmap->N = M;
3346   if (sizesset && newMat->cmap->N < 0) newMat->cmap->N = N;
3347 
3348   /* If global sizes are set, check if they are consistent with that given in the file */
3349   if (sizesset) {
3350     ierr = MatGetSize(newMat,&grows,&gcols);CHKERRQ(ierr);
3351   }
3352   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);
3353   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);
3354 
3355   /* determine ownership of all (block) rows */
3356   if (M%bs) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_FILE_UNEXPECTED, "Inconsistent # of rows (%d) and block size (%d)",M,bs);
3357   if (newMat->rmap->n < 0) m = bs*((M/bs)/size + (((M/bs) % size) > rank));    /* PETSC_DECIDE */
3358   else m = newMat->rmap->n; /* Set by user */
3359 
3360   ierr = PetscMalloc1((size+1),&rowners);CHKERRQ(ierr);
3361   ierr = MPI_Allgather(&m,1,MPIU_INT,rowners+1,1,MPIU_INT,comm);CHKERRQ(ierr);
3362 
3363   /* First process needs enough room for process with most rows */
3364   if (!rank) {
3365     mmax = rowners[1];
3366     for (i=2; i<=size; i++) {
3367       mmax = PetscMax(mmax, rowners[i]);
3368     }
3369   } else mmax = -1;             /* unused, but compilers complain */
3370 
3371   rowners[0] = 0;
3372   for (i=2; i<=size; i++) {
3373     rowners[i] += rowners[i-1];
3374   }
3375   rstart = rowners[rank];
3376   rend   = rowners[rank+1];
3377 
3378   /* distribute row lengths to all processors */
3379   ierr = PetscMalloc2(m,&ourlens,m,&offlens);CHKERRQ(ierr);
3380   if (!rank) {
3381     ierr = PetscBinaryRead(fd,ourlens,m,PETSC_INT);CHKERRQ(ierr);
3382     ierr = PetscMalloc1(mmax,&rowlengths);CHKERRQ(ierr);
3383     ierr = PetscCalloc1(size,&procsnz);CHKERRQ(ierr);
3384     for (j=0; j<m; j++) {
3385       procsnz[0] += ourlens[j];
3386     }
3387     for (i=1; i<size; i++) {
3388       ierr = PetscBinaryRead(fd,rowlengths,rowners[i+1]-rowners[i],PETSC_INT);CHKERRQ(ierr);
3389       /* calculate the number of nonzeros on each processor */
3390       for (j=0; j<rowners[i+1]-rowners[i]; j++) {
3391         procsnz[i] += rowlengths[j];
3392       }
3393       ierr = MPIULong_Send(rowlengths,rowners[i+1]-rowners[i],MPIU_INT,i,tag,comm);CHKERRQ(ierr);
3394     }
3395     ierr = PetscFree(rowlengths);CHKERRQ(ierr);
3396   } else {
3397     ierr = MPIULong_Recv(ourlens,m,MPIU_INT,0,tag,comm);CHKERRQ(ierr);
3398   }
3399 
3400   if (!rank) {
3401     /* determine max buffer needed and allocate it */
3402     maxnz = 0;
3403     for (i=0; i<size; i++) {
3404       maxnz = PetscMax(maxnz,procsnz[i]);
3405     }
3406     ierr = PetscMalloc1(maxnz,&cols);CHKERRQ(ierr);
3407 
3408     /* read in my part of the matrix column indices  */
3409     nz   = procsnz[0];
3410     ierr = PetscMalloc1(nz,&mycols);CHKERRQ(ierr);
3411     ierr = PetscBinaryRead(fd,mycols,nz,PETSC_INT);CHKERRQ(ierr);
3412 
3413     /* read in every one elses and ship off */
3414     for (i=1; i<size; i++) {
3415       nz   = procsnz[i];
3416       ierr = PetscBinaryRead(fd,cols,nz,PETSC_INT);CHKERRQ(ierr);
3417       ierr = MPIULong_Send(cols,nz,MPIU_INT,i,tag,comm);CHKERRQ(ierr);
3418     }
3419     ierr = PetscFree(cols);CHKERRQ(ierr);
3420   } else {
3421     /* determine buffer space needed for message */
3422     nz = 0;
3423     for (i=0; i<m; i++) {
3424       nz += ourlens[i];
3425     }
3426     ierr = PetscMalloc1(nz,&mycols);CHKERRQ(ierr);
3427 
3428     /* receive message of column indices*/
3429     ierr = MPIULong_Recv(mycols,nz,MPIU_INT,0,tag,comm);CHKERRQ(ierr);
3430   }
3431 
3432   /* determine column ownership if matrix is not square */
3433   if (N != M) {
3434     if (newMat->cmap->n < 0) n = N/size + ((N % size) > rank);
3435     else n = newMat->cmap->n;
3436     ierr   = MPI_Scan(&n,&cend,1,MPIU_INT,MPI_SUM,comm);CHKERRQ(ierr);
3437     cstart = cend - n;
3438   } else {
3439     cstart = rstart;
3440     cend   = rend;
3441     n      = cend - cstart;
3442   }
3443 
3444   /* loop over local rows, determining number of off diagonal entries */
3445   ierr = PetscMemzero(offlens,m*sizeof(PetscInt));CHKERRQ(ierr);
3446   jj   = 0;
3447   for (i=0; i<m; i++) {
3448     for (j=0; j<ourlens[i]; j++) {
3449       if (mycols[jj] < cstart || mycols[jj] >= cend) offlens[i]++;
3450       jj++;
3451     }
3452   }
3453 
3454   for (i=0; i<m; i++) {
3455     ourlens[i] -= offlens[i];
3456   }
3457   if (!sizesset) {
3458     ierr = MatSetSizes(newMat,m,n,M,N);CHKERRQ(ierr);
3459   }
3460 
3461   if (bs > 1) {ierr = MatSetBlockSize(newMat,bs);CHKERRQ(ierr);}
3462 
3463   ierr = MatMPIAIJSetPreallocation(newMat,0,ourlens,0,offlens);CHKERRQ(ierr);
3464 
3465   for (i=0; i<m; i++) {
3466     ourlens[i] += offlens[i];
3467   }
3468 
3469   if (!rank) {
3470     ierr = PetscMalloc1((maxnz+1),&vals);CHKERRQ(ierr);
3471 
3472     /* read in my part of the matrix numerical values  */
3473     nz   = procsnz[0];
3474     ierr = PetscBinaryRead(fd,vals,nz,PETSC_SCALAR);CHKERRQ(ierr);
3475 
3476     /* insert into matrix */
3477     jj      = rstart;
3478     smycols = mycols;
3479     svals   = vals;
3480     for (i=0; i<m; i++) {
3481       ierr     = MatSetValues_MPIAIJ(newMat,1,&jj,ourlens[i],smycols,svals,INSERT_VALUES);CHKERRQ(ierr);
3482       smycols += ourlens[i];
3483       svals   += ourlens[i];
3484       jj++;
3485     }
3486 
3487     /* read in other processors and ship out */
3488     for (i=1; i<size; i++) {
3489       nz   = procsnz[i];
3490       ierr = PetscBinaryRead(fd,vals,nz,PETSC_SCALAR);CHKERRQ(ierr);
3491       ierr = MPIULong_Send(vals,nz,MPIU_SCALAR,i,((PetscObject)newMat)->tag,comm);CHKERRQ(ierr);
3492     }
3493     ierr = PetscFree(procsnz);CHKERRQ(ierr);
3494   } else {
3495     /* receive numeric values */
3496     ierr = PetscMalloc1((nz+1),&vals);CHKERRQ(ierr);
3497 
3498     /* receive message of values*/
3499     ierr = MPIULong_Recv(vals,nz,MPIU_SCALAR,0,((PetscObject)newMat)->tag,comm);CHKERRQ(ierr);
3500 
3501     /* insert into matrix */
3502     jj      = rstart;
3503     smycols = mycols;
3504     svals   = vals;
3505     for (i=0; i<m; i++) {
3506       ierr     = MatSetValues_MPIAIJ(newMat,1,&jj,ourlens[i],smycols,svals,INSERT_VALUES);CHKERRQ(ierr);
3507       smycols += ourlens[i];
3508       svals   += ourlens[i];
3509       jj++;
3510     }
3511   }
3512   ierr = PetscFree2(ourlens,offlens);CHKERRQ(ierr);
3513   ierr = PetscFree(vals);CHKERRQ(ierr);
3514   ierr = PetscFree(mycols);CHKERRQ(ierr);
3515   ierr = PetscFree(rowners);CHKERRQ(ierr);
3516   ierr = MatAssemblyBegin(newMat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
3517   ierr = MatAssemblyEnd(newMat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
3518   PetscFunctionReturn(0);
3519 }
3520 
3521 #undef __FUNCT__
3522 #define __FUNCT__ "MatGetSubMatrix_MPIAIJ"
3523 PetscErrorCode MatGetSubMatrix_MPIAIJ(Mat mat,IS isrow,IS iscol,MatReuse call,Mat *newmat)
3524 {
3525   PetscErrorCode ierr;
3526   IS             iscol_local;
3527   PetscInt       csize;
3528 
3529   PetscFunctionBegin;
3530   ierr = ISGetLocalSize(iscol,&csize);CHKERRQ(ierr);
3531   if (call == MAT_REUSE_MATRIX) {
3532     ierr = PetscObjectQuery((PetscObject)*newmat,"ISAllGather",(PetscObject*)&iscol_local);CHKERRQ(ierr);
3533     if (!iscol_local) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"Submatrix passed in was not used before, cannot reuse");
3534   } else {
3535     PetscInt cbs;
3536     ierr = ISGetBlockSize(iscol,&cbs);CHKERRQ(ierr);
3537     ierr = ISAllGather(iscol,&iscol_local);CHKERRQ(ierr);
3538     ierr = ISSetBlockSize(iscol_local,cbs);CHKERRQ(ierr);
3539   }
3540   ierr = MatGetSubMatrix_MPIAIJ_Private(mat,isrow,iscol_local,csize,call,newmat);CHKERRQ(ierr);
3541   if (call == MAT_INITIAL_MATRIX) {
3542     ierr = PetscObjectCompose((PetscObject)*newmat,"ISAllGather",(PetscObject)iscol_local);CHKERRQ(ierr);
3543     ierr = ISDestroy(&iscol_local);CHKERRQ(ierr);
3544   }
3545   PetscFunctionReturn(0);
3546 }
3547 
3548 extern PetscErrorCode MatGetSubMatrices_MPIAIJ_Local(Mat,PetscInt,const IS[],const IS[],MatReuse,PetscBool*,Mat*);
3549 #undef __FUNCT__
3550 #define __FUNCT__ "MatGetSubMatrix_MPIAIJ_Private"
3551 /*
3552     Not great since it makes two copies of the submatrix, first an SeqAIJ
3553   in local and then by concatenating the local matrices the end result.
3554   Writing it directly would be much like MatGetSubMatrices_MPIAIJ()
3555 
3556   Note: This requires a sequential iscol with all indices.
3557 */
3558 PetscErrorCode MatGetSubMatrix_MPIAIJ_Private(Mat mat,IS isrow,IS iscol,PetscInt csize,MatReuse call,Mat *newmat)
3559 {
3560   PetscErrorCode ierr;
3561   PetscMPIInt    rank,size;
3562   PetscInt       i,m,n,rstart,row,rend,nz,*cwork,j,bs,cbs;
3563   PetscInt       *ii,*jj,nlocal,*dlens,*olens,dlen,olen,jend,mglobal,ncol;
3564   PetscBool      allcolumns, colflag;
3565   Mat            M,Mreuse;
3566   MatScalar      *vwork,*aa;
3567   MPI_Comm       comm;
3568   Mat_SeqAIJ     *aij;
3569 
3570   PetscFunctionBegin;
3571   ierr = PetscObjectGetComm((PetscObject)mat,&comm);CHKERRQ(ierr);
3572   ierr = MPI_Comm_rank(comm,&rank);CHKERRQ(ierr);
3573   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
3574 
3575   ierr = ISIdentity(iscol,&colflag);CHKERRQ(ierr);
3576   ierr = ISGetLocalSize(iscol,&ncol);CHKERRQ(ierr);
3577   if (colflag && ncol == mat->cmap->N) {
3578     allcolumns = PETSC_TRUE;
3579   } else {
3580     allcolumns = PETSC_FALSE;
3581   }
3582   if (call ==  MAT_REUSE_MATRIX) {
3583     ierr = PetscObjectQuery((PetscObject)*newmat,"SubMatrix",(PetscObject*)&Mreuse);CHKERRQ(ierr);
3584     if (!Mreuse) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"Submatrix passed in was not used before, cannot reuse");
3585     ierr = MatGetSubMatrices_MPIAIJ_Local(mat,1,&isrow,&iscol,MAT_REUSE_MATRIX,&allcolumns,&Mreuse);CHKERRQ(ierr);
3586   } else {
3587     ierr = MatGetSubMatrices_MPIAIJ_Local(mat,1,&isrow,&iscol,MAT_INITIAL_MATRIX,&allcolumns,&Mreuse);CHKERRQ(ierr);
3588   }
3589 
3590   /*
3591       m - number of local rows
3592       n - number of columns (same on all processors)
3593       rstart - first row in new global matrix generated
3594   */
3595   ierr = MatGetSize(Mreuse,&m,&n);CHKERRQ(ierr);
3596   ierr = MatGetBlockSizes(Mreuse,&bs,&cbs);CHKERRQ(ierr);
3597   if (call == MAT_INITIAL_MATRIX) {
3598     aij = (Mat_SeqAIJ*)(Mreuse)->data;
3599     ii  = aij->i;
3600     jj  = aij->j;
3601 
3602     /*
3603         Determine the number of non-zeros in the diagonal and off-diagonal
3604         portions of the matrix in order to do correct preallocation
3605     */
3606 
3607     /* first get start and end of "diagonal" columns */
3608     if (csize == PETSC_DECIDE) {
3609       ierr = ISGetSize(isrow,&mglobal);CHKERRQ(ierr);
3610       if (mglobal == n) { /* square matrix */
3611         nlocal = m;
3612       } else {
3613         nlocal = n/size + ((n % size) > rank);
3614       }
3615     } else {
3616       nlocal = csize;
3617     }
3618     ierr   = MPI_Scan(&nlocal,&rend,1,MPIU_INT,MPI_SUM,comm);CHKERRQ(ierr);
3619     rstart = rend - nlocal;
3620     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);
3621 
3622     /* next, compute all the lengths */
3623     ierr  = PetscMalloc1((2*m+1),&dlens);CHKERRQ(ierr);
3624     olens = dlens + m;
3625     for (i=0; i<m; i++) {
3626       jend = ii[i+1] - ii[i];
3627       olen = 0;
3628       dlen = 0;
3629       for (j=0; j<jend; j++) {
3630         if (*jj < rstart || *jj >= rend) olen++;
3631         else dlen++;
3632         jj++;
3633       }
3634       olens[i] = olen;
3635       dlens[i] = dlen;
3636     }
3637     ierr = MatCreate(comm,&M);CHKERRQ(ierr);
3638     ierr = MatSetSizes(M,m,nlocal,PETSC_DECIDE,n);CHKERRQ(ierr);
3639     ierr = MatSetBlockSizes(M,bs,cbs);CHKERRQ(ierr);
3640     ierr = MatSetType(M,((PetscObject)mat)->type_name);CHKERRQ(ierr);
3641     ierr = MatMPIAIJSetPreallocation(M,0,dlens,0,olens);CHKERRQ(ierr);
3642     ierr = PetscFree(dlens);CHKERRQ(ierr);
3643   } else {
3644     PetscInt ml,nl;
3645 
3646     M    = *newmat;
3647     ierr = MatGetLocalSize(M,&ml,&nl);CHKERRQ(ierr);
3648     if (ml != m) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_SIZ,"Previous matrix must be same size/layout as request");
3649     ierr = MatZeroEntries(M);CHKERRQ(ierr);
3650     /*
3651          The next two lines are needed so we may call MatSetValues_MPIAIJ() below directly,
3652        rather than the slower MatSetValues().
3653     */
3654     M->was_assembled = PETSC_TRUE;
3655     M->assembled     = PETSC_FALSE;
3656   }
3657   ierr = MatGetOwnershipRange(M,&rstart,&rend);CHKERRQ(ierr);
3658   aij  = (Mat_SeqAIJ*)(Mreuse)->data;
3659   ii   = aij->i;
3660   jj   = aij->j;
3661   aa   = aij->a;
3662   for (i=0; i<m; i++) {
3663     row   = rstart + i;
3664     nz    = ii[i+1] - ii[i];
3665     cwork = jj;     jj += nz;
3666     vwork = aa;     aa += nz;
3667     ierr  = MatSetValues_MPIAIJ(M,1,&row,nz,cwork,vwork,INSERT_VALUES);CHKERRQ(ierr);
3668   }
3669 
3670   ierr    = MatAssemblyBegin(M,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
3671   ierr    = MatAssemblyEnd(M,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
3672   *newmat = M;
3673 
3674   /* save submatrix used in processor for next request */
3675   if (call ==  MAT_INITIAL_MATRIX) {
3676     ierr = PetscObjectCompose((PetscObject)M,"SubMatrix",(PetscObject)Mreuse);CHKERRQ(ierr);
3677     ierr = MatDestroy(&Mreuse);CHKERRQ(ierr);
3678   }
3679   PetscFunctionReturn(0);
3680 }
3681 
3682 #undef __FUNCT__
3683 #define __FUNCT__ "MatMPIAIJSetPreallocationCSR_MPIAIJ"
3684 PetscErrorCode  MatMPIAIJSetPreallocationCSR_MPIAIJ(Mat B,const PetscInt Ii[],const PetscInt J[],const PetscScalar v[])
3685 {
3686   PetscInt       m,cstart, cend,j,nnz,i,d;
3687   PetscInt       *d_nnz,*o_nnz,nnz_max = 0,rstart,ii;
3688   const PetscInt *JJ;
3689   PetscScalar    *values;
3690   PetscErrorCode ierr;
3691 
3692   PetscFunctionBegin;
3693   if (Ii[0]) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Ii[0] must be 0 it is %D",Ii[0]);
3694 
3695   ierr   = PetscLayoutSetUp(B->rmap);CHKERRQ(ierr);
3696   ierr   = PetscLayoutSetUp(B->cmap);CHKERRQ(ierr);
3697   m      = B->rmap->n;
3698   cstart = B->cmap->rstart;
3699   cend   = B->cmap->rend;
3700   rstart = B->rmap->rstart;
3701 
3702   ierr = PetscMalloc2(m,&d_nnz,m,&o_nnz);CHKERRQ(ierr);
3703 
3704 #if defined(PETSC_USE_DEBUGGING)
3705   for (i=0; i<m; i++) {
3706     nnz = Ii[i+1]- Ii[i];
3707     JJ  = J + Ii[i];
3708     if (nnz < 0) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Local row %D has a negative %D number of columns",i,nnz);
3709     if (nnz && (JJ[0] < 0)) SETERRRQ1(PETSC_ERR_ARG_WRONGSTATE,"Row %D starts with negative column index",i,j);
3710     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);
3711   }
3712 #endif
3713 
3714   for (i=0; i<m; i++) {
3715     nnz     = Ii[i+1]- Ii[i];
3716     JJ      = J + Ii[i];
3717     nnz_max = PetscMax(nnz_max,nnz);
3718     d       = 0;
3719     for (j=0; j<nnz; j++) {
3720       if (cstart <= JJ[j] && JJ[j] < cend) d++;
3721     }
3722     d_nnz[i] = d;
3723     o_nnz[i] = nnz - d;
3724   }
3725   ierr = MatMPIAIJSetPreallocation(B,0,d_nnz,0,o_nnz);CHKERRQ(ierr);
3726   ierr = PetscFree2(d_nnz,o_nnz);CHKERRQ(ierr);
3727 
3728   if (v) values = (PetscScalar*)v;
3729   else {
3730     ierr = PetscCalloc1((nnz_max+1),&values);CHKERRQ(ierr);
3731   }
3732 
3733   for (i=0; i<m; i++) {
3734     ii   = i + rstart;
3735     nnz  = Ii[i+1]- Ii[i];
3736     ierr = MatSetValues_MPIAIJ(B,1,&ii,nnz,J+Ii[i],values+(v ? Ii[i] : 0),INSERT_VALUES);CHKERRQ(ierr);
3737   }
3738   ierr = MatAssemblyBegin(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
3739   ierr = MatAssemblyEnd(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
3740 
3741   if (!v) {
3742     ierr = PetscFree(values);CHKERRQ(ierr);
3743   }
3744   ierr = MatSetOption(B,MAT_NEW_NONZERO_LOCATION_ERR,PETSC_TRUE);CHKERRQ(ierr);
3745   PetscFunctionReturn(0);
3746 }
3747 
3748 #undef __FUNCT__
3749 #define __FUNCT__ "MatMPIAIJSetPreallocationCSR"
3750 /*@
3751    MatMPIAIJSetPreallocationCSR - Allocates memory for a sparse parallel matrix in AIJ format
3752    (the default parallel PETSc format).
3753 
3754    Collective on MPI_Comm
3755 
3756    Input Parameters:
3757 +  B - the matrix
3758 .  i - the indices into j for the start of each local row (starts with zero)
3759 .  j - the column indices for each local row (starts with zero)
3760 -  v - optional values in the matrix
3761 
3762    Level: developer
3763 
3764    Notes:
3765        The i, j, and a arrays ARE copied by this routine into the internal format used by PETSc;
3766      thus you CANNOT change the matrix entries by changing the values of a[] after you have
3767      called this routine. Use MatCreateMPIAIJWithSplitArrays() to avoid needing to copy the arrays.
3768 
3769        The i and j indices are 0 based, and i indices are indices corresponding to the local j array.
3770 
3771        The format which is used for the sparse matrix input, is equivalent to a
3772     row-major ordering.. i.e for the following matrix, the input data expected is
3773     as shown:
3774 
3775         1 0 0
3776         2 0 3     P0
3777        -------
3778         4 5 6     P1
3779 
3780      Process0 [P0]: rows_owned=[0,1]
3781         i =  {0,1,3}  [size = nrow+1  = 2+1]
3782         j =  {0,0,2}  [size = nz = 6]
3783         v =  {1,2,3}  [size = nz = 6]
3784 
3785      Process1 [P1]: rows_owned=[2]
3786         i =  {0,3}    [size = nrow+1  = 1+1]
3787         j =  {0,1,2}  [size = nz = 6]
3788         v =  {4,5,6}  [size = nz = 6]
3789 
3790 .keywords: matrix, aij, compressed row, sparse, parallel
3791 
3792 .seealso: MatCreate(), MatCreateSeqAIJ(), MatSetValues(), MatMPIAIJSetPreallocation(), MatCreateAIJ(), MPIAIJ,
3793           MatCreateSeqAIJWithArrays(), MatCreateMPIAIJWithSplitArrays()
3794 @*/
3795 PetscErrorCode  MatMPIAIJSetPreallocationCSR(Mat B,const PetscInt i[],const PetscInt j[], const PetscScalar v[])
3796 {
3797   PetscErrorCode ierr;
3798 
3799   PetscFunctionBegin;
3800   ierr = PetscTryMethod(B,"MatMPIAIJSetPreallocationCSR_C",(Mat,const PetscInt[],const PetscInt[],const PetscScalar[]),(B,i,j,v));CHKERRQ(ierr);
3801   PetscFunctionReturn(0);
3802 }
3803 
3804 #undef __FUNCT__
3805 #define __FUNCT__ "MatMPIAIJSetPreallocation"
3806 /*@C
3807    MatMPIAIJSetPreallocation - Preallocates memory for a sparse parallel matrix in AIJ format
3808    (the default parallel PETSc format).  For good matrix assembly performance
3809    the user should preallocate the matrix storage by setting the parameters
3810    d_nz (or d_nnz) and o_nz (or o_nnz).  By setting these parameters accurately,
3811    performance can be increased by more than a factor of 50.
3812 
3813    Collective on MPI_Comm
3814 
3815    Input Parameters:
3816 +  B - the matrix
3817 .  d_nz  - number of nonzeros per row in DIAGONAL portion of local submatrix
3818            (same value is used for all local rows)
3819 .  d_nnz - array containing the number of nonzeros in the various rows of the
3820            DIAGONAL portion of the local submatrix (possibly different for each row)
3821            or NULL, if d_nz is used to specify the nonzero structure.
3822            The size of this array is equal to the number of local rows, i.e 'm'.
3823            For matrices that will be factored, you must leave room for (and set)
3824            the diagonal entry even if it is zero.
3825 .  o_nz  - number of nonzeros per row in the OFF-DIAGONAL portion of local
3826            submatrix (same value is used for all local rows).
3827 -  o_nnz - array containing the number of nonzeros in the various rows of the
3828            OFF-DIAGONAL portion of the local submatrix (possibly different for
3829            each row) or NULL, if o_nz is used to specify the nonzero
3830            structure. The size of this array is equal to the number
3831            of local rows, i.e 'm'.
3832 
3833    If the *_nnz parameter is given then the *_nz parameter is ignored
3834 
3835    The AIJ format (also called the Yale sparse matrix format or
3836    compressed row storage (CSR)), is fully compatible with standard Fortran 77
3837    storage.  The stored row and column indices begin with zero.
3838    See Users-Manual: ch_mat for details.
3839 
3840    The parallel matrix is partitioned such that the first m0 rows belong to
3841    process 0, the next m1 rows belong to process 1, the next m2 rows belong
3842    to process 2 etc.. where m0,m1,m2... are the input parameter 'm'.
3843 
3844    The DIAGONAL portion of the local submatrix of a processor can be defined
3845    as the submatrix which is obtained by extraction the part corresponding to
3846    the rows r1-r2 and columns c1-c2 of the global matrix, where r1 is the
3847    first row that belongs to the processor, r2 is the last row belonging to
3848    the this processor, and c1-c2 is range of indices of the local part of a
3849    vector suitable for applying the matrix to.  This is an mxn matrix.  In the
3850    common case of a square matrix, the row and column ranges are the same and
3851    the DIAGONAL part is also square. The remaining portion of the local
3852    submatrix (mxN) constitute the OFF-DIAGONAL portion.
3853 
3854    If o_nnz, d_nnz are specified, then o_nz, and d_nz are ignored.
3855 
3856    You can call MatGetInfo() to get information on how effective the preallocation was;
3857    for example the fields mallocs,nz_allocated,nz_used,nz_unneeded;
3858    You can also run with the option -info and look for messages with the string
3859    malloc in them to see if additional memory allocation was needed.
3860 
3861    Example usage:
3862 
3863    Consider the following 8x8 matrix with 34 non-zero values, that is
3864    assembled across 3 processors. Lets assume that proc0 owns 3 rows,
3865    proc1 owns 3 rows, proc2 owns 2 rows. This division can be shown
3866    as follows:
3867 
3868 .vb
3869             1  2  0  |  0  3  0  |  0  4
3870     Proc0   0  5  6  |  7  0  0  |  8  0
3871             9  0 10  | 11  0  0  | 12  0
3872     -------------------------------------
3873            13  0 14  | 15 16 17  |  0  0
3874     Proc1   0 18  0  | 19 20 21  |  0  0
3875             0  0  0  | 22 23  0  | 24  0
3876     -------------------------------------
3877     Proc2  25 26 27  |  0  0 28  | 29  0
3878            30  0  0  | 31 32 33  |  0 34
3879 .ve
3880 
3881    This can be represented as a collection of submatrices as:
3882 
3883 .vb
3884       A B C
3885       D E F
3886       G H I
3887 .ve
3888 
3889    Where the submatrices A,B,C are owned by proc0, D,E,F are
3890    owned by proc1, G,H,I are owned by proc2.
3891 
3892    The 'm' parameters for proc0,proc1,proc2 are 3,3,2 respectively.
3893    The 'n' parameters for proc0,proc1,proc2 are 3,3,2 respectively.
3894    The 'M','N' parameters are 8,8, and have the same values on all procs.
3895 
3896    The DIAGONAL submatrices corresponding to proc0,proc1,proc2 are
3897    submatrices [A], [E], [I] respectively. The OFF-DIAGONAL submatrices
3898    corresponding to proc0,proc1,proc2 are [BC], [DF], [GH] respectively.
3899    Internally, each processor stores the DIAGONAL part, and the OFF-DIAGONAL
3900    part as SeqAIJ matrices. for eg: proc1 will store [E] as a SeqAIJ
3901    matrix, ans [DF] as another SeqAIJ matrix.
3902 
3903    When d_nz, o_nz parameters are specified, d_nz storage elements are
3904    allocated for every row of the local diagonal submatrix, and o_nz
3905    storage locations are allocated for every row of the OFF-DIAGONAL submat.
3906    One way to choose d_nz and o_nz is to use the max nonzerors per local
3907    rows for each of the local DIAGONAL, and the OFF-DIAGONAL submatrices.
3908    In this case, the values of d_nz,o_nz are:
3909 .vb
3910      proc0 : dnz = 2, o_nz = 2
3911      proc1 : dnz = 3, o_nz = 2
3912      proc2 : dnz = 1, o_nz = 4
3913 .ve
3914    We are allocating m*(d_nz+o_nz) storage locations for every proc. This
3915    translates to 3*(2+2)=12 for proc0, 3*(3+2)=15 for proc1, 2*(1+4)=10
3916    for proc3. i.e we are using 12+15+10=37 storage locations to store
3917    34 values.
3918 
3919    When d_nnz, o_nnz parameters are specified, the storage is specified
3920    for every row, coresponding to both DIAGONAL and OFF-DIAGONAL submatrices.
3921    In the above case the values for d_nnz,o_nnz are:
3922 .vb
3923      proc0: d_nnz = [2,2,2] and o_nnz = [2,2,2]
3924      proc1: d_nnz = [3,3,2] and o_nnz = [2,1,1]
3925      proc2: d_nnz = [1,1]   and o_nnz = [4,4]
3926 .ve
3927    Here the space allocated is sum of all the above values i.e 34, and
3928    hence pre-allocation is perfect.
3929 
3930    Level: intermediate
3931 
3932 .keywords: matrix, aij, compressed row, sparse, parallel
3933 
3934 .seealso: MatCreate(), MatCreateSeqAIJ(), MatSetValues(), MatCreateAIJ(), MatMPIAIJSetPreallocationCSR(),
3935           MPIAIJ, MatGetInfo(), PetscSplitOwnership()
3936 @*/
3937 PetscErrorCode  MatMPIAIJSetPreallocation(Mat B,PetscInt d_nz,const PetscInt d_nnz[],PetscInt o_nz,const PetscInt o_nnz[])
3938 {
3939   PetscErrorCode ierr;
3940 
3941   PetscFunctionBegin;
3942   PetscValidHeaderSpecific(B,MAT_CLASSID,1);
3943   PetscValidType(B,1);
3944   ierr = PetscTryMethod(B,"MatMPIAIJSetPreallocation_C",(Mat,PetscInt,const PetscInt[],PetscInt,const PetscInt[]),(B,d_nz,d_nnz,o_nz,o_nnz));CHKERRQ(ierr);
3945   PetscFunctionReturn(0);
3946 }
3947 
3948 #undef __FUNCT__
3949 #define __FUNCT__ "MatCreateMPIAIJWithArrays"
3950 /*@
3951      MatCreateMPIAIJWithArrays - creates a MPI AIJ matrix using arrays that contain in standard
3952          CSR format the local rows.
3953 
3954    Collective on MPI_Comm
3955 
3956    Input Parameters:
3957 +  comm - MPI communicator
3958 .  m - number of local rows (Cannot be PETSC_DECIDE)
3959 .  n - This value should be the same as the local size used in creating the
3960        x vector for the matrix-vector product y = Ax. (or PETSC_DECIDE to have
3961        calculated if N is given) For square matrices n is almost always m.
3962 .  M - number of global rows (or PETSC_DETERMINE to have calculated if m is given)
3963 .  N - number of global columns (or PETSC_DETERMINE to have calculated if n is given)
3964 .   i - row indices
3965 .   j - column indices
3966 -   a - matrix values
3967 
3968    Output Parameter:
3969 .   mat - the matrix
3970 
3971    Level: intermediate
3972 
3973    Notes:
3974        The i, j, and a arrays ARE copied by this routine into the internal format used by PETSc;
3975      thus you CANNOT change the matrix entries by changing the values of a[] after you have
3976      called this routine. Use MatCreateMPIAIJWithSplitArrays() to avoid needing to copy the arrays.
3977 
3978        The i and j indices are 0 based, and i indices are indices corresponding to the local j array.
3979 
3980        The format which is used for the sparse matrix input, is equivalent to a
3981     row-major ordering.. i.e for the following matrix, the input data expected is
3982     as shown:
3983 
3984         1 0 0
3985         2 0 3     P0
3986        -------
3987         4 5 6     P1
3988 
3989      Process0 [P0]: rows_owned=[0,1]
3990         i =  {0,1,3}  [size = nrow+1  = 2+1]
3991         j =  {0,0,2}  [size = nz = 6]
3992         v =  {1,2,3}  [size = nz = 6]
3993 
3994      Process1 [P1]: rows_owned=[2]
3995         i =  {0,3}    [size = nrow+1  = 1+1]
3996         j =  {0,1,2}  [size = nz = 6]
3997         v =  {4,5,6}  [size = nz = 6]
3998 
3999 .keywords: matrix, aij, compressed row, sparse, parallel
4000 
4001 .seealso: MatCreate(), MatCreateSeqAIJ(), MatSetValues(), MatMPIAIJSetPreallocation(), MatMPIAIJSetPreallocationCSR(),
4002           MPIAIJ, MatCreateAIJ(), MatCreateMPIAIJWithSplitArrays()
4003 @*/
4004 PetscErrorCode  MatCreateMPIAIJWithArrays(MPI_Comm comm,PetscInt m,PetscInt n,PetscInt M,PetscInt N,const PetscInt i[],const PetscInt j[],const PetscScalar a[],Mat *mat)
4005 {
4006   PetscErrorCode ierr;
4007 
4008   PetscFunctionBegin;
4009   if (i[0]) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"i (row indices) must start with 0");
4010   if (m < 0) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"local number of rows (m) cannot be PETSC_DECIDE, or negative");
4011   ierr = MatCreate(comm,mat);CHKERRQ(ierr);
4012   ierr = MatSetSizes(*mat,m,n,M,N);CHKERRQ(ierr);
4013   /* ierr = MatSetBlockSizes(M,bs,cbs);CHKERRQ(ierr); */
4014   ierr = MatSetType(*mat,MATMPIAIJ);CHKERRQ(ierr);
4015   ierr = MatMPIAIJSetPreallocationCSR(*mat,i,j,a);CHKERRQ(ierr);
4016   PetscFunctionReturn(0);
4017 }
4018 
4019 #undef __FUNCT__
4020 #define __FUNCT__ "MatCreateAIJ"
4021 /*@C
4022    MatCreateAIJ - Creates a sparse parallel matrix in AIJ format
4023    (the default parallel PETSc format).  For good matrix assembly performance
4024    the user should preallocate the matrix storage by setting the parameters
4025    d_nz (or d_nnz) and o_nz (or o_nnz).  By setting these parameters accurately,
4026    performance can be increased by more than a factor of 50.
4027 
4028    Collective on MPI_Comm
4029 
4030    Input Parameters:
4031 +  comm - MPI communicator
4032 .  m - number of local rows (or PETSC_DECIDE to have calculated if M is given)
4033            This value should be the same as the local size used in creating the
4034            y vector for the matrix-vector product y = Ax.
4035 .  n - This value should be the same as the local size used in creating the
4036        x vector for the matrix-vector product y = Ax. (or PETSC_DECIDE to have
4037        calculated if N is given) For square matrices n is almost always m.
4038 .  M - number of global rows (or PETSC_DETERMINE to have calculated if m is given)
4039 .  N - number of global columns (or PETSC_DETERMINE to have calculated if n is given)
4040 .  d_nz  - number of nonzeros per row in DIAGONAL portion of local submatrix
4041            (same value is used for all local rows)
4042 .  d_nnz - array containing the number of nonzeros in the various rows of the
4043            DIAGONAL portion of the local submatrix (possibly different for each row)
4044            or NULL, if d_nz is used to specify the nonzero structure.
4045            The size of this array is equal to the number of local rows, i.e 'm'.
4046 .  o_nz  - number of nonzeros per row in the OFF-DIAGONAL portion of local
4047            submatrix (same value is used for all local rows).
4048 -  o_nnz - array containing the number of nonzeros in the various rows of the
4049            OFF-DIAGONAL portion of the local submatrix (possibly different for
4050            each row) or NULL, if o_nz is used to specify the nonzero
4051            structure. The size of this array is equal to the number
4052            of local rows, i.e 'm'.
4053 
4054    Output Parameter:
4055 .  A - the matrix
4056 
4057    It is recommended that one use the MatCreate(), MatSetType() and/or MatSetFromOptions(),
4058    MatXXXXSetPreallocation() paradgm instead of this routine directly.
4059    [MatXXXXSetPreallocation() is, for example, MatSeqAIJSetPreallocation]
4060 
4061    Notes:
4062    If the *_nnz parameter is given then the *_nz parameter is ignored
4063 
4064    m,n,M,N parameters specify the size of the matrix, and its partitioning across
4065    processors, while d_nz,d_nnz,o_nz,o_nnz parameters specify the approximate
4066    storage requirements for this matrix.
4067 
4068    If PETSC_DECIDE or  PETSC_DETERMINE is used for a particular argument on one
4069    processor than it must be used on all processors that share the object for
4070    that argument.
4071 
4072    The user MUST specify either the local or global matrix dimensions
4073    (possibly both).
4074 
4075    The parallel matrix is partitioned across processors such that the
4076    first m0 rows belong to process 0, the next m1 rows belong to
4077    process 1, the next m2 rows belong to process 2 etc.. where
4078    m0,m1,m2,.. are the input parameter 'm'. i.e each processor stores
4079    values corresponding to [m x N] submatrix.
4080 
4081    The columns are logically partitioned with the n0 columns belonging
4082    to 0th partition, the next n1 columns belonging to the next
4083    partition etc.. where n0,n1,n2... are the input parameter 'n'.
4084 
4085    The DIAGONAL portion of the local submatrix on any given processor
4086    is the submatrix corresponding to the rows and columns m,n
4087    corresponding to the given processor. i.e diagonal matrix on
4088    process 0 is [m0 x n0], diagonal matrix on process 1 is [m1 x n1]
4089    etc. The remaining portion of the local submatrix [m x (N-n)]
4090    constitute the OFF-DIAGONAL portion. The example below better
4091    illustrates this concept.
4092 
4093    For a square global matrix we define each processor's diagonal portion
4094    to be its local rows and the corresponding columns (a square submatrix);
4095    each processor's off-diagonal portion encompasses the remainder of the
4096    local matrix (a rectangular submatrix).
4097 
4098    If o_nnz, d_nnz are specified, then o_nz, and d_nz are ignored.
4099 
4100    When calling this routine with a single process communicator, a matrix of
4101    type SEQAIJ is returned.  If a matrix of type MPIAIJ is desired for this
4102    type of communicator, use the construction mechanism:
4103      MatCreate(...,&A); MatSetType(A,MATMPIAIJ); MatSetSizes(A, m,n,M,N); MatMPIAIJSetPreallocation(A,...);
4104 
4105    By default, this format uses inodes (identical nodes) when possible.
4106    We search for consecutive rows with the same nonzero structure, thereby
4107    reusing matrix information to achieve increased efficiency.
4108 
4109    Options Database Keys:
4110 +  -mat_no_inode  - Do not use inodes
4111 .  -mat_inode_limit <limit> - Sets inode limit (max limit=5)
4112 -  -mat_aij_oneindex - Internally use indexing starting at 1
4113         rather than 0.  Note that when calling MatSetValues(),
4114         the user still MUST index entries starting at 0!
4115 
4116 
4117    Example usage:
4118 
4119    Consider the following 8x8 matrix with 34 non-zero values, that is
4120    assembled across 3 processors. Lets assume that proc0 owns 3 rows,
4121    proc1 owns 3 rows, proc2 owns 2 rows. This division can be shown
4122    as follows:
4123 
4124 .vb
4125             1  2  0  |  0  3  0  |  0  4
4126     Proc0   0  5  6  |  7  0  0  |  8  0
4127             9  0 10  | 11  0  0  | 12  0
4128     -------------------------------------
4129            13  0 14  | 15 16 17  |  0  0
4130     Proc1   0 18  0  | 19 20 21  |  0  0
4131             0  0  0  | 22 23  0  | 24  0
4132     -------------------------------------
4133     Proc2  25 26 27  |  0  0 28  | 29  0
4134            30  0  0  | 31 32 33  |  0 34
4135 .ve
4136 
4137    This can be represented as a collection of submatrices as:
4138 
4139 .vb
4140       A B C
4141       D E F
4142       G H I
4143 .ve
4144 
4145    Where the submatrices A,B,C are owned by proc0, D,E,F are
4146    owned by proc1, G,H,I are owned by proc2.
4147 
4148    The 'm' parameters for proc0,proc1,proc2 are 3,3,2 respectively.
4149    The 'n' parameters for proc0,proc1,proc2 are 3,3,2 respectively.
4150    The 'M','N' parameters are 8,8, and have the same values on all procs.
4151 
4152    The DIAGONAL submatrices corresponding to proc0,proc1,proc2 are
4153    submatrices [A], [E], [I] respectively. The OFF-DIAGONAL submatrices
4154    corresponding to proc0,proc1,proc2 are [BC], [DF], [GH] respectively.
4155    Internally, each processor stores the DIAGONAL part, and the OFF-DIAGONAL
4156    part as SeqAIJ matrices. for eg: proc1 will store [E] as a SeqAIJ
4157    matrix, ans [DF] as another SeqAIJ matrix.
4158 
4159    When d_nz, o_nz parameters are specified, d_nz storage elements are
4160    allocated for every row of the local diagonal submatrix, and o_nz
4161    storage locations are allocated for every row of the OFF-DIAGONAL submat.
4162    One way to choose d_nz and o_nz is to use the max nonzerors per local
4163    rows for each of the local DIAGONAL, and the OFF-DIAGONAL submatrices.
4164    In this case, the values of d_nz,o_nz are:
4165 .vb
4166      proc0 : dnz = 2, o_nz = 2
4167      proc1 : dnz = 3, o_nz = 2
4168      proc2 : dnz = 1, o_nz = 4
4169 .ve
4170    We are allocating m*(d_nz+o_nz) storage locations for every proc. This
4171    translates to 3*(2+2)=12 for proc0, 3*(3+2)=15 for proc1, 2*(1+4)=10
4172    for proc3. i.e we are using 12+15+10=37 storage locations to store
4173    34 values.
4174 
4175    When d_nnz, o_nnz parameters are specified, the storage is specified
4176    for every row, coresponding to both DIAGONAL and OFF-DIAGONAL submatrices.
4177    In the above case the values for d_nnz,o_nnz are:
4178 .vb
4179      proc0: d_nnz = [2,2,2] and o_nnz = [2,2,2]
4180      proc1: d_nnz = [3,3,2] and o_nnz = [2,1,1]
4181      proc2: d_nnz = [1,1]   and o_nnz = [4,4]
4182 .ve
4183    Here the space allocated is sum of all the above values i.e 34, and
4184    hence pre-allocation is perfect.
4185 
4186    Level: intermediate
4187 
4188 .keywords: matrix, aij, compressed row, sparse, parallel
4189 
4190 .seealso: MatCreate(), MatCreateSeqAIJ(), MatSetValues(), MatMPIAIJSetPreallocation(), MatMPIAIJSetPreallocationCSR(),
4191           MPIAIJ, MatCreateMPIAIJWithArrays()
4192 @*/
4193 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)
4194 {
4195   PetscErrorCode ierr;
4196   PetscMPIInt    size;
4197 
4198   PetscFunctionBegin;
4199   ierr = MatCreate(comm,A);CHKERRQ(ierr);
4200   ierr = MatSetSizes(*A,m,n,M,N);CHKERRQ(ierr);
4201   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
4202   if (size > 1) {
4203     ierr = MatSetType(*A,MATMPIAIJ);CHKERRQ(ierr);
4204     ierr = MatMPIAIJSetPreallocation(*A,d_nz,d_nnz,o_nz,o_nnz);CHKERRQ(ierr);
4205   } else {
4206     ierr = MatSetType(*A,MATSEQAIJ);CHKERRQ(ierr);
4207     ierr = MatSeqAIJSetPreallocation(*A,d_nz,d_nnz);CHKERRQ(ierr);
4208   }
4209   PetscFunctionReturn(0);
4210 }
4211 
4212 #undef __FUNCT__
4213 #define __FUNCT__ "MatMPIAIJGetSeqAIJ"
4214 PetscErrorCode  MatMPIAIJGetSeqAIJ(Mat A,Mat *Ad,Mat *Ao,const PetscInt *colmap[])
4215 {
4216   Mat_MPIAIJ *a = (Mat_MPIAIJ*)A->data;
4217 
4218   PetscFunctionBegin;
4219   if (Ad)     *Ad     = a->A;
4220   if (Ao)     *Ao     = a->B;
4221   if (colmap) *colmap = a->garray;
4222   PetscFunctionReturn(0);
4223 }
4224 
4225 #undef __FUNCT__
4226 #define __FUNCT__ "MatSetColoring_MPIAIJ"
4227 PetscErrorCode MatSetColoring_MPIAIJ(Mat A,ISColoring coloring)
4228 {
4229   PetscErrorCode ierr;
4230   PetscInt       i;
4231   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
4232 
4233   PetscFunctionBegin;
4234   if (coloring->ctype == IS_COLORING_GLOBAL) {
4235     ISColoringValue *allcolors,*colors;
4236     ISColoring      ocoloring;
4237 
4238     /* set coloring for diagonal portion */
4239     ierr = MatSetColoring_SeqAIJ(a->A,coloring);CHKERRQ(ierr);
4240 
4241     /* set coloring for off-diagonal portion */
4242     ierr = ISAllGatherColors(PetscObjectComm((PetscObject)A),coloring->n,coloring->colors,NULL,&allcolors);CHKERRQ(ierr);
4243     ierr = PetscMalloc1((a->B->cmap->n+1),&colors);CHKERRQ(ierr);
4244     for (i=0; i<a->B->cmap->n; i++) {
4245       colors[i] = allcolors[a->garray[i]];
4246     }
4247     ierr = PetscFree(allcolors);CHKERRQ(ierr);
4248     ierr = ISColoringCreate(MPI_COMM_SELF,coloring->n,a->B->cmap->n,colors,&ocoloring);CHKERRQ(ierr);
4249     ierr = MatSetColoring_SeqAIJ(a->B,ocoloring);CHKERRQ(ierr);
4250     ierr = ISColoringDestroy(&ocoloring);CHKERRQ(ierr);
4251   } else if (coloring->ctype == IS_COLORING_GHOSTED) {
4252     ISColoringValue *colors;
4253     PetscInt        *larray;
4254     ISColoring      ocoloring;
4255 
4256     /* set coloring for diagonal portion */
4257     ierr = PetscMalloc1((a->A->cmap->n+1),&larray);CHKERRQ(ierr);
4258     for (i=0; i<a->A->cmap->n; i++) {
4259       larray[i] = i + A->cmap->rstart;
4260     }
4261     ierr = ISGlobalToLocalMappingApply(A->cmap->mapping,IS_GTOLM_MASK,a->A->cmap->n,larray,NULL,larray);CHKERRQ(ierr);
4262     ierr = PetscMalloc1((a->A->cmap->n+1),&colors);CHKERRQ(ierr);
4263     for (i=0; i<a->A->cmap->n; i++) {
4264       colors[i] = coloring->colors[larray[i]];
4265     }
4266     ierr = PetscFree(larray);CHKERRQ(ierr);
4267     ierr = ISColoringCreate(PETSC_COMM_SELF,coloring->n,a->A->cmap->n,colors,&ocoloring);CHKERRQ(ierr);
4268     ierr = MatSetColoring_SeqAIJ(a->A,ocoloring);CHKERRQ(ierr);
4269     ierr = ISColoringDestroy(&ocoloring);CHKERRQ(ierr);
4270 
4271     /* set coloring for off-diagonal portion */
4272     ierr = PetscMalloc1((a->B->cmap->n+1),&larray);CHKERRQ(ierr);
4273     ierr = ISGlobalToLocalMappingApply(A->cmap->mapping,IS_GTOLM_MASK,a->B->cmap->n,a->garray,NULL,larray);CHKERRQ(ierr);
4274     ierr = PetscMalloc1((a->B->cmap->n+1),&colors);CHKERRQ(ierr);
4275     for (i=0; i<a->B->cmap->n; i++) {
4276       colors[i] = coloring->colors[larray[i]];
4277     }
4278     ierr = PetscFree(larray);CHKERRQ(ierr);
4279     ierr = ISColoringCreate(MPI_COMM_SELF,coloring->n,a->B->cmap->n,colors,&ocoloring);CHKERRQ(ierr);
4280     ierr = MatSetColoring_SeqAIJ(a->B,ocoloring);CHKERRQ(ierr);
4281     ierr = ISColoringDestroy(&ocoloring);CHKERRQ(ierr);
4282   } else SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_SUP,"No support ISColoringType %d",(int)coloring->ctype);
4283   PetscFunctionReturn(0);
4284 }
4285 
4286 #undef __FUNCT__
4287 #define __FUNCT__ "MatSetValuesAdifor_MPIAIJ"
4288 PetscErrorCode MatSetValuesAdifor_MPIAIJ(Mat A,PetscInt nl,void *advalues)
4289 {
4290   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
4291   PetscErrorCode ierr;
4292 
4293   PetscFunctionBegin;
4294   ierr = MatSetValuesAdifor_SeqAIJ(a->A,nl,advalues);CHKERRQ(ierr);
4295   ierr = MatSetValuesAdifor_SeqAIJ(a->B,nl,advalues);CHKERRQ(ierr);
4296   PetscFunctionReturn(0);
4297 }
4298 
4299 #undef __FUNCT__
4300 #define __FUNCT__ "MatCreateMPIAIJConcatenateSeqAIJSymbolic"
4301 PetscErrorCode MatCreateMPIAIJConcatenateSeqAIJSymbolic(MPI_Comm comm,Mat inmat,PetscInt n,Mat *outmat)
4302 {
4303   PetscErrorCode ierr;
4304   PetscInt       m,N,i,rstart,nnz,*dnz,*onz,sum,bs,cbs;
4305   PetscInt       *indx;
4306 
4307   PetscFunctionBegin;
4308   /* This routine will ONLY return MPIAIJ type matrix */
4309   ierr = MatGetSize(inmat,&m,&N);CHKERRQ(ierr);
4310   ierr = MatGetBlockSizes(inmat,&bs,&cbs);CHKERRQ(ierr);
4311   if (n == PETSC_DECIDE) {
4312     ierr = PetscSplitOwnership(comm,&n,&N);CHKERRQ(ierr);
4313   }
4314   /* Check sum(n) = N */
4315   ierr = MPI_Allreduce(&n,&sum,1,MPIU_INT,MPI_SUM,comm);CHKERRQ(ierr);
4316   if (sum != N) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_INCOMP,"Sum of local columns != global columns %d",N);
4317 
4318   ierr    = MPI_Scan(&m, &rstart,1,MPIU_INT,MPI_SUM,comm);CHKERRQ(ierr);
4319   rstart -= m;
4320 
4321   ierr = MatPreallocateInitialize(comm,m,n,dnz,onz);CHKERRQ(ierr);
4322   for (i=0; i<m; i++) {
4323     ierr = MatGetRow_SeqAIJ(inmat,i,&nnz,&indx,NULL);CHKERRQ(ierr);
4324     ierr = MatPreallocateSet(i+rstart,nnz,indx,dnz,onz);CHKERRQ(ierr);
4325     ierr = MatRestoreRow_SeqAIJ(inmat,i,&nnz,&indx,NULL);CHKERRQ(ierr);
4326   }
4327 
4328   ierr = MatCreate(comm,outmat);CHKERRQ(ierr);
4329   ierr = MatSetSizes(*outmat,m,n,PETSC_DETERMINE,PETSC_DETERMINE);CHKERRQ(ierr);
4330   ierr = MatSetBlockSizes(*outmat,bs,cbs);CHKERRQ(ierr);
4331   ierr = MatSetType(*outmat,MATMPIAIJ);CHKERRQ(ierr);
4332   ierr = MatMPIAIJSetPreallocation(*outmat,0,dnz,0,onz);CHKERRQ(ierr);
4333   ierr = MatPreallocateFinalize(dnz,onz);CHKERRQ(ierr);
4334   PetscFunctionReturn(0);
4335 }
4336 
4337 #undef __FUNCT__
4338 #define __FUNCT__ "MatCreateMPIAIJConcatenateSeqAIJNumeric"
4339 PetscErrorCode  MatCreateMPIAIJConcatenateSeqAIJNumeric(MPI_Comm comm,Mat inmat,PetscInt n,Mat outmat)
4340 {
4341   PetscErrorCode ierr;
4342   PetscInt       m,N,i,rstart,nnz,Ii;
4343   PetscInt       *indx;
4344   PetscScalar    *values;
4345 
4346   PetscFunctionBegin;
4347   ierr = MatGetSize(inmat,&m,&N);CHKERRQ(ierr);
4348   ierr = MatGetOwnershipRange(outmat,&rstart,NULL);CHKERRQ(ierr);
4349   for (i=0; i<m; i++) {
4350     ierr = MatGetRow_SeqAIJ(inmat,i,&nnz,&indx,&values);CHKERRQ(ierr);
4351     Ii   = i + rstart;
4352     ierr = MatSetValues(outmat,1,&Ii,nnz,indx,values,INSERT_VALUES);CHKERRQ(ierr);
4353     ierr = MatRestoreRow_SeqAIJ(inmat,i,&nnz,&indx,&values);CHKERRQ(ierr);
4354   }
4355   ierr = MatAssemblyBegin(outmat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
4356   ierr = MatAssemblyEnd(outmat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
4357   PetscFunctionReturn(0);
4358 }
4359 
4360 #undef __FUNCT__
4361 #define __FUNCT__ "MatCreateMPIMatConcatenateSeqMat_MPIAIJ"
4362 PetscErrorCode MatCreateMPIMatConcatenateSeqMat_MPIAIJ(MPI_Comm comm,Mat inmat,PetscInt n,MatReuse scall,Mat *outmat)
4363 {
4364   PetscErrorCode ierr;
4365   PetscMPIInt    size;
4366 
4367   PetscFunctionBegin;
4368   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
4369   ierr = PetscLogEventBegin(MAT_Merge,inmat,0,0,0);CHKERRQ(ierr);
4370   if (size == 1) {
4371     if (scall == MAT_INITIAL_MATRIX) {
4372       ierr = MatDuplicate(inmat,MAT_COPY_VALUES,outmat);CHKERRQ(ierr);
4373     } else {
4374       ierr = MatCopy(inmat,*outmat,SAME_NONZERO_PATTERN);CHKERRQ(ierr);
4375     }
4376   } else {
4377     if (scall == MAT_INITIAL_MATRIX) {
4378       ierr = MatCreateMPIAIJConcatenateSeqAIJSymbolic(comm,inmat,n,outmat);CHKERRQ(ierr);
4379     }
4380     ierr = MatCreateMPIAIJConcatenateSeqAIJNumeric(comm,inmat,n,*outmat);CHKERRQ(ierr);
4381   }
4382   ierr = PetscLogEventEnd(MAT_Merge,inmat,0,0,0);CHKERRQ(ierr);
4383   PetscFunctionReturn(0);
4384 }
4385 
4386 #undef __FUNCT__
4387 #define __FUNCT__ "MatFileSplit"
4388 PetscErrorCode MatFileSplit(Mat A,char *outfile)
4389 {
4390   PetscErrorCode    ierr;
4391   PetscMPIInt       rank;
4392   PetscInt          m,N,i,rstart,nnz;
4393   size_t            len;
4394   const PetscInt    *indx;
4395   PetscViewer       out;
4396   char              *name;
4397   Mat               B;
4398   const PetscScalar *values;
4399 
4400   PetscFunctionBegin;
4401   ierr = MatGetLocalSize(A,&m,0);CHKERRQ(ierr);
4402   ierr = MatGetSize(A,0,&N);CHKERRQ(ierr);
4403   /* Should this be the type of the diagonal block of A? */
4404   ierr = MatCreate(PETSC_COMM_SELF,&B);CHKERRQ(ierr);
4405   ierr = MatSetSizes(B,m,N,m,N);CHKERRQ(ierr);
4406   ierr = MatSetBlockSizesFromMats(B,A,A);CHKERRQ(ierr);
4407   ierr = MatSetType(B,MATSEQAIJ);CHKERRQ(ierr);
4408   ierr = MatSeqAIJSetPreallocation(B,0,NULL);CHKERRQ(ierr);
4409   ierr = MatGetOwnershipRange(A,&rstart,0);CHKERRQ(ierr);
4410   for (i=0; i<m; i++) {
4411     ierr = MatGetRow(A,i+rstart,&nnz,&indx,&values);CHKERRQ(ierr);
4412     ierr = MatSetValues(B,1,&i,nnz,indx,values,INSERT_VALUES);CHKERRQ(ierr);
4413     ierr = MatRestoreRow(A,i+rstart,&nnz,&indx,&values);CHKERRQ(ierr);
4414   }
4415   ierr = MatAssemblyBegin(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
4416   ierr = MatAssemblyEnd(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
4417 
4418   ierr = MPI_Comm_rank(PetscObjectComm((PetscObject)A),&rank);CHKERRQ(ierr);
4419   ierr = PetscStrlen(outfile,&len);CHKERRQ(ierr);
4420   ierr = PetscMalloc1((len+5),&name);CHKERRQ(ierr);
4421   sprintf(name,"%s.%d",outfile,rank);
4422   ierr = PetscViewerBinaryOpen(PETSC_COMM_SELF,name,FILE_MODE_APPEND,&out);CHKERRQ(ierr);
4423   ierr = PetscFree(name);CHKERRQ(ierr);
4424   ierr = MatView(B,out);CHKERRQ(ierr);
4425   ierr = PetscViewerDestroy(&out);CHKERRQ(ierr);
4426   ierr = MatDestroy(&B);CHKERRQ(ierr);
4427   PetscFunctionReturn(0);
4428 }
4429 
4430 extern PetscErrorCode MatDestroy_MPIAIJ(Mat);
4431 #undef __FUNCT__
4432 #define __FUNCT__ "MatDestroy_MPIAIJ_SeqsToMPI"
4433 PetscErrorCode  MatDestroy_MPIAIJ_SeqsToMPI(Mat A)
4434 {
4435   PetscErrorCode      ierr;
4436   Mat_Merge_SeqsToMPI *merge;
4437   PetscContainer      container;
4438 
4439   PetscFunctionBegin;
4440   ierr = PetscObjectQuery((PetscObject)A,"MatMergeSeqsToMPI",(PetscObject*)&container);CHKERRQ(ierr);
4441   if (container) {
4442     ierr = PetscContainerGetPointer(container,(void**)&merge);CHKERRQ(ierr);
4443     ierr = PetscFree(merge->id_r);CHKERRQ(ierr);
4444     ierr = PetscFree(merge->len_s);CHKERRQ(ierr);
4445     ierr = PetscFree(merge->len_r);CHKERRQ(ierr);
4446     ierr = PetscFree(merge->bi);CHKERRQ(ierr);
4447     ierr = PetscFree(merge->bj);CHKERRQ(ierr);
4448     ierr = PetscFree(merge->buf_ri[0]);CHKERRQ(ierr);
4449     ierr = PetscFree(merge->buf_ri);CHKERRQ(ierr);
4450     ierr = PetscFree(merge->buf_rj[0]);CHKERRQ(ierr);
4451     ierr = PetscFree(merge->buf_rj);CHKERRQ(ierr);
4452     ierr = PetscFree(merge->coi);CHKERRQ(ierr);
4453     ierr = PetscFree(merge->coj);CHKERRQ(ierr);
4454     ierr = PetscFree(merge->owners_co);CHKERRQ(ierr);
4455     ierr = PetscLayoutDestroy(&merge->rowmap);CHKERRQ(ierr);
4456     ierr = PetscFree(merge);CHKERRQ(ierr);
4457     ierr = PetscObjectCompose((PetscObject)A,"MatMergeSeqsToMPI",0);CHKERRQ(ierr);
4458   }
4459   ierr = MatDestroy_MPIAIJ(A);CHKERRQ(ierr);
4460   PetscFunctionReturn(0);
4461 }
4462 
4463 #include <../src/mat/utils/freespace.h>
4464 #include <petscbt.h>
4465 
4466 #undef __FUNCT__
4467 #define __FUNCT__ "MatCreateMPIAIJSumSeqAIJNumeric"
4468 PetscErrorCode  MatCreateMPIAIJSumSeqAIJNumeric(Mat seqmat,Mat mpimat)
4469 {
4470   PetscErrorCode      ierr;
4471   MPI_Comm            comm;
4472   Mat_SeqAIJ          *a  =(Mat_SeqAIJ*)seqmat->data;
4473   PetscMPIInt         size,rank,taga,*len_s;
4474   PetscInt            N=mpimat->cmap->N,i,j,*owners,*ai=a->i,*aj;
4475   PetscInt            proc,m;
4476   PetscInt            **buf_ri,**buf_rj;
4477   PetscInt            k,anzi,*bj_i,*bi,*bj,arow,bnzi,nextaj;
4478   PetscInt            nrows,**buf_ri_k,**nextrow,**nextai;
4479   MPI_Request         *s_waits,*r_waits;
4480   MPI_Status          *status;
4481   MatScalar           *aa=a->a;
4482   MatScalar           **abuf_r,*ba_i;
4483   Mat_Merge_SeqsToMPI *merge;
4484   PetscContainer      container;
4485 
4486   PetscFunctionBegin;
4487   ierr = PetscObjectGetComm((PetscObject)mpimat,&comm);CHKERRQ(ierr);
4488   ierr = PetscLogEventBegin(MAT_Seqstompinum,seqmat,0,0,0);CHKERRQ(ierr);
4489 
4490   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
4491   ierr = MPI_Comm_rank(comm,&rank);CHKERRQ(ierr);
4492 
4493   ierr = PetscObjectQuery((PetscObject)mpimat,"MatMergeSeqsToMPI",(PetscObject*)&container);CHKERRQ(ierr);
4494   ierr = PetscContainerGetPointer(container,(void**)&merge);CHKERRQ(ierr);
4495 
4496   bi     = merge->bi;
4497   bj     = merge->bj;
4498   buf_ri = merge->buf_ri;
4499   buf_rj = merge->buf_rj;
4500 
4501   ierr   = PetscMalloc1(size,&status);CHKERRQ(ierr);
4502   owners = merge->rowmap->range;
4503   len_s  = merge->len_s;
4504 
4505   /* send and recv matrix values */
4506   /*-----------------------------*/
4507   ierr = PetscObjectGetNewTag((PetscObject)mpimat,&taga);CHKERRQ(ierr);
4508   ierr = PetscPostIrecvScalar(comm,taga,merge->nrecv,merge->id_r,merge->len_r,&abuf_r,&r_waits);CHKERRQ(ierr);
4509 
4510   ierr = PetscMalloc1((merge->nsend+1),&s_waits);CHKERRQ(ierr);
4511   for (proc=0,k=0; proc<size; proc++) {
4512     if (!len_s[proc]) continue;
4513     i    = owners[proc];
4514     ierr = MPI_Isend(aa+ai[i],len_s[proc],MPIU_MATSCALAR,proc,taga,comm,s_waits+k);CHKERRQ(ierr);
4515     k++;
4516   }
4517 
4518   if (merge->nrecv) {ierr = MPI_Waitall(merge->nrecv,r_waits,status);CHKERRQ(ierr);}
4519   if (merge->nsend) {ierr = MPI_Waitall(merge->nsend,s_waits,status);CHKERRQ(ierr);}
4520   ierr = PetscFree(status);CHKERRQ(ierr);
4521 
4522   ierr = PetscFree(s_waits);CHKERRQ(ierr);
4523   ierr = PetscFree(r_waits);CHKERRQ(ierr);
4524 
4525   /* insert mat values of mpimat */
4526   /*----------------------------*/
4527   ierr = PetscMalloc1(N,&ba_i);CHKERRQ(ierr);
4528   ierr = PetscMalloc3(merge->nrecv,&buf_ri_k,merge->nrecv,&nextrow,merge->nrecv,&nextai);CHKERRQ(ierr);
4529 
4530   for (k=0; k<merge->nrecv; k++) {
4531     buf_ri_k[k] = buf_ri[k]; /* beginning of k-th recved i-structure */
4532     nrows       = *(buf_ri_k[k]);
4533     nextrow[k]  = buf_ri_k[k]+1;  /* next row number of k-th recved i-structure */
4534     nextai[k]   = buf_ri_k[k] + (nrows + 1); /* poins to the next i-structure of k-th recved i-structure  */
4535   }
4536 
4537   /* set values of ba */
4538   m = merge->rowmap->n;
4539   for (i=0; i<m; i++) {
4540     arow = owners[rank] + i;
4541     bj_i = bj+bi[i];  /* col indices of the i-th row of mpimat */
4542     bnzi = bi[i+1] - bi[i];
4543     ierr = PetscMemzero(ba_i,bnzi*sizeof(PetscScalar));CHKERRQ(ierr);
4544 
4545     /* add local non-zero vals of this proc's seqmat into ba */
4546     anzi   = ai[arow+1] - ai[arow];
4547     aj     = a->j + ai[arow];
4548     aa     = a->a + ai[arow];
4549     nextaj = 0;
4550     for (j=0; nextaj<anzi; j++) {
4551       if (*(bj_i + j) == aj[nextaj]) { /* bcol == acol */
4552         ba_i[j] += aa[nextaj++];
4553       }
4554     }
4555 
4556     /* add received vals into ba */
4557     for (k=0; k<merge->nrecv; k++) { /* k-th received message */
4558       /* i-th row */
4559       if (i == *nextrow[k]) {
4560         anzi   = *(nextai[k]+1) - *nextai[k];
4561         aj     = buf_rj[k] + *(nextai[k]);
4562         aa     = abuf_r[k] + *(nextai[k]);
4563         nextaj = 0;
4564         for (j=0; nextaj<anzi; j++) {
4565           if (*(bj_i + j) == aj[nextaj]) { /* bcol == acol */
4566             ba_i[j] += aa[nextaj++];
4567           }
4568         }
4569         nextrow[k]++; nextai[k]++;
4570       }
4571     }
4572     ierr = MatSetValues(mpimat,1,&arow,bnzi,bj_i,ba_i,INSERT_VALUES);CHKERRQ(ierr);
4573   }
4574   ierr = MatAssemblyBegin(mpimat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
4575   ierr = MatAssemblyEnd(mpimat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
4576 
4577   ierr = PetscFree(abuf_r[0]);CHKERRQ(ierr);
4578   ierr = PetscFree(abuf_r);CHKERRQ(ierr);
4579   ierr = PetscFree(ba_i);CHKERRQ(ierr);
4580   ierr = PetscFree3(buf_ri_k,nextrow,nextai);CHKERRQ(ierr);
4581   ierr = PetscLogEventEnd(MAT_Seqstompinum,seqmat,0,0,0);CHKERRQ(ierr);
4582   PetscFunctionReturn(0);
4583 }
4584 
4585 extern PetscErrorCode  MatDestroy_MPIAIJ_SeqsToMPI(Mat);
4586 
4587 #undef __FUNCT__
4588 #define __FUNCT__ "MatCreateMPIAIJSumSeqAIJSymbolic"
4589 PetscErrorCode  MatCreateMPIAIJSumSeqAIJSymbolic(MPI_Comm comm,Mat seqmat,PetscInt m,PetscInt n,Mat *mpimat)
4590 {
4591   PetscErrorCode      ierr;
4592   Mat                 B_mpi;
4593   Mat_SeqAIJ          *a=(Mat_SeqAIJ*)seqmat->data;
4594   PetscMPIInt         size,rank,tagi,tagj,*len_s,*len_si,*len_ri;
4595   PetscInt            **buf_rj,**buf_ri,**buf_ri_k;
4596   PetscInt            M=seqmat->rmap->n,N=seqmat->cmap->n,i,*owners,*ai=a->i,*aj=a->j;
4597   PetscInt            len,proc,*dnz,*onz,bs,cbs;
4598   PetscInt            k,anzi,*bi,*bj,*lnk,nlnk,arow,bnzi,nspacedouble=0;
4599   PetscInt            nrows,*buf_s,*buf_si,*buf_si_i,**nextrow,**nextai;
4600   MPI_Request         *si_waits,*sj_waits,*ri_waits,*rj_waits;
4601   MPI_Status          *status;
4602   PetscFreeSpaceList  free_space=NULL,current_space=NULL;
4603   PetscBT             lnkbt;
4604   Mat_Merge_SeqsToMPI *merge;
4605   PetscContainer      container;
4606 
4607   PetscFunctionBegin;
4608   ierr = PetscLogEventBegin(MAT_Seqstompisym,seqmat,0,0,0);CHKERRQ(ierr);
4609 
4610   /* make sure it is a PETSc comm */
4611   ierr = PetscCommDuplicate(comm,&comm,NULL);CHKERRQ(ierr);
4612   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
4613   ierr = MPI_Comm_rank(comm,&rank);CHKERRQ(ierr);
4614 
4615   ierr = PetscNew(&merge);CHKERRQ(ierr);
4616   ierr = PetscMalloc1(size,&status);CHKERRQ(ierr);
4617 
4618   /* determine row ownership */
4619   /*---------------------------------------------------------*/
4620   ierr = PetscLayoutCreate(comm,&merge->rowmap);CHKERRQ(ierr);
4621   ierr = PetscLayoutSetLocalSize(merge->rowmap,m);CHKERRQ(ierr);
4622   ierr = PetscLayoutSetSize(merge->rowmap,M);CHKERRQ(ierr);
4623   ierr = PetscLayoutSetBlockSize(merge->rowmap,1);CHKERRQ(ierr);
4624   ierr = PetscLayoutSetUp(merge->rowmap);CHKERRQ(ierr);
4625   ierr = PetscMalloc1(size,&len_si);CHKERRQ(ierr);
4626   ierr = PetscMalloc1(size,&merge->len_s);CHKERRQ(ierr);
4627 
4628   m      = merge->rowmap->n;
4629   owners = merge->rowmap->range;
4630 
4631   /* determine the number of messages to send, their lengths */
4632   /*---------------------------------------------------------*/
4633   len_s = merge->len_s;
4634 
4635   len          = 0; /* length of buf_si[] */
4636   merge->nsend = 0;
4637   for (proc=0; proc<size; proc++) {
4638     len_si[proc] = 0;
4639     if (proc == rank) {
4640       len_s[proc] = 0;
4641     } else {
4642       len_si[proc] = owners[proc+1] - owners[proc] + 1;
4643       len_s[proc]  = ai[owners[proc+1]] - ai[owners[proc]]; /* num of rows to be sent to [proc] */
4644     }
4645     if (len_s[proc]) {
4646       merge->nsend++;
4647       nrows = 0;
4648       for (i=owners[proc]; i<owners[proc+1]; i++) {
4649         if (ai[i+1] > ai[i]) nrows++;
4650       }
4651       len_si[proc] = 2*(nrows+1);
4652       len         += len_si[proc];
4653     }
4654   }
4655 
4656   /* determine the number and length of messages to receive for ij-structure */
4657   /*-------------------------------------------------------------------------*/
4658   ierr = PetscGatherNumberOfMessages(comm,NULL,len_s,&merge->nrecv);CHKERRQ(ierr);
4659   ierr = PetscGatherMessageLengths2(comm,merge->nsend,merge->nrecv,len_s,len_si,&merge->id_r,&merge->len_r,&len_ri);CHKERRQ(ierr);
4660 
4661   /* post the Irecv of j-structure */
4662   /*-------------------------------*/
4663   ierr = PetscCommGetNewTag(comm,&tagj);CHKERRQ(ierr);
4664   ierr = PetscPostIrecvInt(comm,tagj,merge->nrecv,merge->id_r,merge->len_r,&buf_rj,&rj_waits);CHKERRQ(ierr);
4665 
4666   /* post the Isend of j-structure */
4667   /*--------------------------------*/
4668   ierr = PetscMalloc2(merge->nsend,&si_waits,merge->nsend,&sj_waits);CHKERRQ(ierr);
4669 
4670   for (proc=0, k=0; proc<size; proc++) {
4671     if (!len_s[proc]) continue;
4672     i    = owners[proc];
4673     ierr = MPI_Isend(aj+ai[i],len_s[proc],MPIU_INT,proc,tagj,comm,sj_waits+k);CHKERRQ(ierr);
4674     k++;
4675   }
4676 
4677   /* receives and sends of j-structure are complete */
4678   /*------------------------------------------------*/
4679   if (merge->nrecv) {ierr = MPI_Waitall(merge->nrecv,rj_waits,status);CHKERRQ(ierr);}
4680   if (merge->nsend) {ierr = MPI_Waitall(merge->nsend,sj_waits,status);CHKERRQ(ierr);}
4681 
4682   /* send and recv i-structure */
4683   /*---------------------------*/
4684   ierr = PetscCommGetNewTag(comm,&tagi);CHKERRQ(ierr);
4685   ierr = PetscPostIrecvInt(comm,tagi,merge->nrecv,merge->id_r,len_ri,&buf_ri,&ri_waits);CHKERRQ(ierr);
4686 
4687   ierr   = PetscMalloc1((len+1),&buf_s);CHKERRQ(ierr);
4688   buf_si = buf_s;  /* points to the beginning of k-th msg to be sent */
4689   for (proc=0,k=0; proc<size; proc++) {
4690     if (!len_s[proc]) continue;
4691     /* form outgoing message for i-structure:
4692          buf_si[0]:                 nrows to be sent
4693                [1:nrows]:           row index (global)
4694                [nrows+1:2*nrows+1]: i-structure index
4695     */
4696     /*-------------------------------------------*/
4697     nrows       = len_si[proc]/2 - 1;
4698     buf_si_i    = buf_si + nrows+1;
4699     buf_si[0]   = nrows;
4700     buf_si_i[0] = 0;
4701     nrows       = 0;
4702     for (i=owners[proc]; i<owners[proc+1]; i++) {
4703       anzi = ai[i+1] - ai[i];
4704       if (anzi) {
4705         buf_si_i[nrows+1] = buf_si_i[nrows] + anzi; /* i-structure */
4706         buf_si[nrows+1]   = i-owners[proc]; /* local row index */
4707         nrows++;
4708       }
4709     }
4710     ierr = MPI_Isend(buf_si,len_si[proc],MPIU_INT,proc,tagi,comm,si_waits+k);CHKERRQ(ierr);
4711     k++;
4712     buf_si += len_si[proc];
4713   }
4714 
4715   if (merge->nrecv) {ierr = MPI_Waitall(merge->nrecv,ri_waits,status);CHKERRQ(ierr);}
4716   if (merge->nsend) {ierr = MPI_Waitall(merge->nsend,si_waits,status);CHKERRQ(ierr);}
4717 
4718   ierr = PetscInfo2(seqmat,"nsend: %D, nrecv: %D\n",merge->nsend,merge->nrecv);CHKERRQ(ierr);
4719   for (i=0; i<merge->nrecv; i++) {
4720     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);
4721   }
4722 
4723   ierr = PetscFree(len_si);CHKERRQ(ierr);
4724   ierr = PetscFree(len_ri);CHKERRQ(ierr);
4725   ierr = PetscFree(rj_waits);CHKERRQ(ierr);
4726   ierr = PetscFree2(si_waits,sj_waits);CHKERRQ(ierr);
4727   ierr = PetscFree(ri_waits);CHKERRQ(ierr);
4728   ierr = PetscFree(buf_s);CHKERRQ(ierr);
4729   ierr = PetscFree(status);CHKERRQ(ierr);
4730 
4731   /* compute a local seq matrix in each processor */
4732   /*----------------------------------------------*/
4733   /* allocate bi array and free space for accumulating nonzero column info */
4734   ierr  = PetscMalloc1((m+1),&bi);CHKERRQ(ierr);
4735   bi[0] = 0;
4736 
4737   /* create and initialize a linked list */
4738   nlnk = N+1;
4739   ierr = PetscLLCreate(N,N,nlnk,lnk,lnkbt);CHKERRQ(ierr);
4740 
4741   /* initial FreeSpace size is 2*(num of local nnz(seqmat)) */
4742   len  = ai[owners[rank+1]] - ai[owners[rank]];
4743   ierr = PetscFreeSpaceGet((PetscInt)(2*len+1),&free_space);CHKERRQ(ierr);
4744 
4745   current_space = free_space;
4746 
4747   /* determine symbolic info for each local row */
4748   ierr = PetscMalloc3(merge->nrecv,&buf_ri_k,merge->nrecv,&nextrow,merge->nrecv,&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   ierr = MatPreallocateInitialize(comm,m,n,dnz,onz);CHKERRQ(ierr);
4758   len  = 0;
4759   for (i=0; i<m; i++) {
4760     bnzi = 0;
4761     /* add local non-zero cols of this proc's seqmat into lnk */
4762     arow  = owners[rank] + i;
4763     anzi  = ai[arow+1] - ai[arow];
4764     aj    = a->j + ai[arow];
4765     ierr  = PetscLLAddSorted(anzi,aj,N,nlnk,lnk,lnkbt);CHKERRQ(ierr);
4766     bnzi += nlnk;
4767     /* add received col data into lnk */
4768     for (k=0; k<merge->nrecv; k++) { /* k-th received message */
4769       if (i == *nextrow[k]) { /* i-th row */
4770         anzi  = *(nextai[k]+1) - *nextai[k];
4771         aj    = buf_rj[k] + *nextai[k];
4772         ierr  = PetscLLAddSorted(anzi,aj,N,nlnk,lnk,lnkbt);CHKERRQ(ierr);
4773         bnzi += nlnk;
4774         nextrow[k]++; nextai[k]++;
4775       }
4776     }
4777     if (len < bnzi) len = bnzi;  /* =max(bnzi) */
4778 
4779     /* if free space is not available, make more free space */
4780     if (current_space->local_remaining<bnzi) {
4781       ierr = PetscFreeSpaceGet(bnzi+current_space->total_array_size,&current_space);CHKERRQ(ierr);
4782       nspacedouble++;
4783     }
4784     /* copy data into free space, then initialize lnk */
4785     ierr = PetscLLClean(N,N,bnzi,lnk,current_space->array,lnkbt);CHKERRQ(ierr);
4786     ierr = MatPreallocateSet(i+owners[rank],bnzi,current_space->array,dnz,onz);CHKERRQ(ierr);
4787 
4788     current_space->array           += bnzi;
4789     current_space->local_used      += bnzi;
4790     current_space->local_remaining -= bnzi;
4791 
4792     bi[i+1] = bi[i] + bnzi;
4793   }
4794 
4795   ierr = PetscFree3(buf_ri_k,nextrow,nextai);CHKERRQ(ierr);
4796 
4797   ierr = PetscMalloc1((bi[m]+1),&bj);CHKERRQ(ierr);
4798   ierr = PetscFreeSpaceContiguous(&free_space,bj);CHKERRQ(ierr);
4799   ierr = PetscLLDestroy(lnk,lnkbt);CHKERRQ(ierr);
4800 
4801   /* create symbolic parallel matrix B_mpi */
4802   /*---------------------------------------*/
4803   ierr = MatGetBlockSizes(seqmat,&bs,&cbs);CHKERRQ(ierr);
4804   ierr = MatCreate(comm,&B_mpi);CHKERRQ(ierr);
4805   if (n==PETSC_DECIDE) {
4806     ierr = MatSetSizes(B_mpi,m,n,PETSC_DETERMINE,N);CHKERRQ(ierr);
4807   } else {
4808     ierr = MatSetSizes(B_mpi,m,n,PETSC_DETERMINE,PETSC_DETERMINE);CHKERRQ(ierr);
4809   }
4810   ierr = MatSetBlockSizes(B_mpi,bs,cbs);CHKERRQ(ierr);
4811   ierr = MatSetType(B_mpi,MATMPIAIJ);CHKERRQ(ierr);
4812   ierr = MatMPIAIJSetPreallocation(B_mpi,0,dnz,0,onz);CHKERRQ(ierr);
4813   ierr = MatPreallocateFinalize(dnz,onz);CHKERRQ(ierr);
4814   ierr = MatSetOption(B_mpi,MAT_NEW_NONZERO_ALLOCATION_ERR,PETSC_FALSE);CHKERRQ(ierr);
4815 
4816   /* B_mpi is not ready for use - assembly will be done by MatCreateMPIAIJSumSeqAIJNumeric() */
4817   B_mpi->assembled    = PETSC_FALSE;
4818   B_mpi->ops->destroy = MatDestroy_MPIAIJ_SeqsToMPI;
4819   merge->bi           = bi;
4820   merge->bj           = bj;
4821   merge->buf_ri       = buf_ri;
4822   merge->buf_rj       = buf_rj;
4823   merge->coi          = NULL;
4824   merge->coj          = NULL;
4825   merge->owners_co    = NULL;
4826 
4827   ierr = PetscCommDestroy(&comm);CHKERRQ(ierr);
4828 
4829   /* attach the supporting struct to B_mpi for reuse */
4830   ierr    = PetscContainerCreate(PETSC_COMM_SELF,&container);CHKERRQ(ierr);
4831   ierr    = PetscContainerSetPointer(container,merge);CHKERRQ(ierr);
4832   ierr    = PetscObjectCompose((PetscObject)B_mpi,"MatMergeSeqsToMPI",(PetscObject)container);CHKERRQ(ierr);
4833   ierr    = PetscContainerDestroy(&container);CHKERRQ(ierr);
4834   *mpimat = B_mpi;
4835 
4836   ierr = PetscLogEventEnd(MAT_Seqstompisym,seqmat,0,0,0);CHKERRQ(ierr);
4837   PetscFunctionReturn(0);
4838 }
4839 
4840 #undef __FUNCT__
4841 #define __FUNCT__ "MatCreateMPIAIJSumSeqAIJ"
4842 /*@C
4843       MatCreateMPIAIJSumSeqAIJ - Creates a MPIAIJ matrix by adding sequential
4844                  matrices from each processor
4845 
4846     Collective on MPI_Comm
4847 
4848    Input Parameters:
4849 +    comm - the communicators the parallel matrix will live on
4850 .    seqmat - the input sequential matrices
4851 .    m - number of local rows (or PETSC_DECIDE)
4852 .    n - number of local columns (or PETSC_DECIDE)
4853 -    scall - either MAT_INITIAL_MATRIX or MAT_REUSE_MATRIX
4854 
4855    Output Parameter:
4856 .    mpimat - the parallel matrix generated
4857 
4858     Level: advanced
4859 
4860    Notes:
4861      The dimensions of the sequential matrix in each processor MUST be the same.
4862      The input seqmat is included into the container "Mat_Merge_SeqsToMPI", and will be
4863      destroyed when mpimat is destroyed. Call PetscObjectQuery() to access seqmat.
4864 @*/
4865 PetscErrorCode  MatCreateMPIAIJSumSeqAIJ(MPI_Comm comm,Mat seqmat,PetscInt m,PetscInt n,MatReuse scall,Mat *mpimat)
4866 {
4867   PetscErrorCode ierr;
4868   PetscMPIInt    size;
4869 
4870   PetscFunctionBegin;
4871   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
4872   if (size == 1) {
4873     ierr = PetscLogEventBegin(MAT_Seqstompi,seqmat,0,0,0);CHKERRQ(ierr);
4874     if (scall == MAT_INITIAL_MATRIX) {
4875       ierr = MatDuplicate(seqmat,MAT_COPY_VALUES,mpimat);CHKERRQ(ierr);
4876     } else {
4877       ierr = MatCopy(seqmat,*mpimat,SAME_NONZERO_PATTERN);CHKERRQ(ierr);
4878     }
4879     ierr = PetscLogEventEnd(MAT_Seqstompi,seqmat,0,0,0);CHKERRQ(ierr);
4880     PetscFunctionReturn(0);
4881   }
4882   ierr = PetscLogEventBegin(MAT_Seqstompi,seqmat,0,0,0);CHKERRQ(ierr);
4883   if (scall == MAT_INITIAL_MATRIX) {
4884     ierr = MatCreateMPIAIJSumSeqAIJSymbolic(comm,seqmat,m,n,mpimat);CHKERRQ(ierr);
4885   }
4886   ierr = MatCreateMPIAIJSumSeqAIJNumeric(seqmat,*mpimat);CHKERRQ(ierr);
4887   ierr = PetscLogEventEnd(MAT_Seqstompi,seqmat,0,0,0);CHKERRQ(ierr);
4888   PetscFunctionReturn(0);
4889 }
4890 
4891 #undef __FUNCT__
4892 #define __FUNCT__ "MatMPIAIJGetLocalMat"
4893 /*@
4894      MatMPIAIJGetLocalMat - Creates a SeqAIJ from a MPIAIJ matrix by taking all its local rows and putting them into a sequential vector with
4895           mlocal rows and n columns. Where mlocal is the row count obtained with MatGetLocalSize() and n is the global column count obtained
4896           with MatGetSize()
4897 
4898     Not Collective
4899 
4900    Input Parameters:
4901 +    A - the matrix
4902 .    scall - either MAT_INITIAL_MATRIX or MAT_REUSE_MATRIX
4903 
4904    Output Parameter:
4905 .    A_loc - the local sequential matrix generated
4906 
4907     Level: developer
4908 
4909 .seealso: MatGetOwnerShipRange(), MatMPIAIJGetLocalMatCondensed()
4910 
4911 @*/
4912 PetscErrorCode  MatMPIAIJGetLocalMat(Mat A,MatReuse scall,Mat *A_loc)
4913 {
4914   PetscErrorCode ierr;
4915   Mat_MPIAIJ     *mpimat=(Mat_MPIAIJ*)A->data;
4916   Mat_SeqAIJ     *mat,*a,*b;
4917   PetscInt       *ai,*aj,*bi,*bj,*cmap=mpimat->garray;
4918   MatScalar      *aa,*ba,*cam;
4919   PetscScalar    *ca;
4920   PetscInt       am=A->rmap->n,i,j,k,cstart=A->cmap->rstart;
4921   PetscInt       *ci,*cj,col,ncols_d,ncols_o,jo;
4922   PetscBool      match;
4923   MPI_Comm       comm;
4924   PetscMPIInt    size;
4925 
4926   PetscFunctionBegin;
4927   ierr = PetscObjectTypeCompare((PetscObject)A,MATMPIAIJ,&match);CHKERRQ(ierr);
4928   if (!match) SETERRQ(PetscObjectComm((PetscObject)A), PETSC_ERR_SUP,"Requires MPIAIJ matrix as input");
4929   ierr = PetscObjectGetComm((PetscObject)A,&comm);CHKERRQ(ierr);
4930   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
4931   if (size == 1 && scall == MAT_REUSE_MATRIX) PetscFunctionReturn(0);
4932 
4933   ierr = PetscLogEventBegin(MAT_Getlocalmat,A,0,0,0);CHKERRQ(ierr);
4934   a = (Mat_SeqAIJ*)(mpimat->A)->data;
4935   b = (Mat_SeqAIJ*)(mpimat->B)->data;
4936   ai = a->i; aj = a->j; bi = b->i; bj = b->j;
4937   aa = a->a; ba = b->a;
4938   if (scall == MAT_INITIAL_MATRIX) {
4939     if (size == 1) {
4940       ierr = MatCreateSeqAIJWithArrays(PETSC_COMM_SELF,am,A->cmap->N,ai,aj,aa,A_loc);CHKERRQ(ierr);
4941       PetscFunctionReturn(0);
4942     }
4943 
4944     ierr  = PetscMalloc1((1+am),&ci);CHKERRQ(ierr);
4945     ci[0] = 0;
4946     for (i=0; i<am; i++) {
4947       ci[i+1] = ci[i] + (ai[i+1] - ai[i]) + (bi[i+1] - bi[i]);
4948     }
4949     ierr = PetscMalloc1((1+ci[am]),&cj);CHKERRQ(ierr);
4950     ierr = PetscMalloc1((1+ci[am]),&ca);CHKERRQ(ierr);
4951     k    = 0;
4952     for (i=0; i<am; i++) {
4953       ncols_o = bi[i+1] - bi[i];
4954       ncols_d = ai[i+1] - ai[i];
4955       /* off-diagonal portion of A */
4956       for (jo=0; jo<ncols_o; jo++) {
4957         col = cmap[*bj];
4958         if (col >= cstart) break;
4959         cj[k]   = col; bj++;
4960         ca[k++] = *ba++;
4961       }
4962       /* diagonal portion of A */
4963       for (j=0; j<ncols_d; j++) {
4964         cj[k]   = cstart + *aj++;
4965         ca[k++] = *aa++;
4966       }
4967       /* off-diagonal portion of A */
4968       for (j=jo; j<ncols_o; j++) {
4969         cj[k]   = cmap[*bj++];
4970         ca[k++] = *ba++;
4971       }
4972     }
4973     /* put together the new matrix */
4974     ierr = MatCreateSeqAIJWithArrays(PETSC_COMM_SELF,am,A->cmap->N,ci,cj,ca,A_loc);CHKERRQ(ierr);
4975     /* MatCreateSeqAIJWithArrays flags matrix so PETSc doesn't free the user's arrays. */
4976     /* Since these are PETSc arrays, change flags to free them as necessary. */
4977     mat          = (Mat_SeqAIJ*)(*A_loc)->data;
4978     mat->free_a  = PETSC_TRUE;
4979     mat->free_ij = PETSC_TRUE;
4980     mat->nonew   = 0;
4981   } else if (scall == MAT_REUSE_MATRIX) {
4982     mat=(Mat_SeqAIJ*)(*A_loc)->data;
4983     ci = mat->i; cj = mat->j; cam = mat->a;
4984     for (i=0; i<am; i++) {
4985       /* off-diagonal portion of A */
4986       ncols_o = bi[i+1] - bi[i];
4987       for (jo=0; jo<ncols_o; jo++) {
4988         col = cmap[*bj];
4989         if (col >= cstart) break;
4990         *cam++ = *ba++; bj++;
4991       }
4992       /* diagonal portion of A */
4993       ncols_d = ai[i+1] - ai[i];
4994       for (j=0; j<ncols_d; j++) *cam++ = *aa++;
4995       /* off-diagonal portion of A */
4996       for (j=jo; j<ncols_o; j++) {
4997         *cam++ = *ba++; bj++;
4998       }
4999     }
5000   } else SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONG,"Invalid MatReuse %d",(int)scall);
5001   ierr = PetscLogEventEnd(MAT_Getlocalmat,A,0,0,0);CHKERRQ(ierr);
5002   PetscFunctionReturn(0);
5003 }
5004 
5005 #undef __FUNCT__
5006 #define __FUNCT__ "MatMPIAIJGetLocalMatCondensed"
5007 /*@C
5008      MatMPIAIJGetLocalMatCondensed - Creates a SeqAIJ matrix from an MPIAIJ matrix by taking all its local rows and NON-ZERO columns
5009 
5010     Not Collective
5011 
5012    Input Parameters:
5013 +    A - the matrix
5014 .    scall - either MAT_INITIAL_MATRIX or MAT_REUSE_MATRIX
5015 -    row, col - index sets of rows and columns to extract (or NULL)
5016 
5017    Output Parameter:
5018 .    A_loc - the local sequential matrix generated
5019 
5020     Level: developer
5021 
5022 .seealso: MatGetOwnershipRange(), MatMPIAIJGetLocalMat()
5023 
5024 @*/
5025 PetscErrorCode  MatMPIAIJGetLocalMatCondensed(Mat A,MatReuse scall,IS *row,IS *col,Mat *A_loc)
5026 {
5027   Mat_MPIAIJ     *a=(Mat_MPIAIJ*)A->data;
5028   PetscErrorCode ierr;
5029   PetscInt       i,start,end,ncols,nzA,nzB,*cmap,imark,*idx;
5030   IS             isrowa,iscola;
5031   Mat            *aloc;
5032   PetscBool      match;
5033 
5034   PetscFunctionBegin;
5035   ierr = PetscObjectTypeCompare((PetscObject)A,MATMPIAIJ,&match);CHKERRQ(ierr);
5036   if (!match) SETERRQ(PetscObjectComm((PetscObject)A), PETSC_ERR_SUP,"Requires MPIAIJ matrix as input");
5037   ierr = PetscLogEventBegin(MAT_Getlocalmatcondensed,A,0,0,0);CHKERRQ(ierr);
5038   if (!row) {
5039     start = A->rmap->rstart; end = A->rmap->rend;
5040     ierr  = ISCreateStride(PETSC_COMM_SELF,end-start,start,1,&isrowa);CHKERRQ(ierr);
5041   } else {
5042     isrowa = *row;
5043   }
5044   if (!col) {
5045     start = A->cmap->rstart;
5046     cmap  = a->garray;
5047     nzA   = a->A->cmap->n;
5048     nzB   = a->B->cmap->n;
5049     ierr  = PetscMalloc1((nzA+nzB), &idx);CHKERRQ(ierr);
5050     ncols = 0;
5051     for (i=0; i<nzB; i++) {
5052       if (cmap[i] < start) idx[ncols++] = cmap[i];
5053       else break;
5054     }
5055     imark = i;
5056     for (i=0; i<nzA; i++) idx[ncols++] = start + i;
5057     for (i=imark; i<nzB; i++) idx[ncols++] = cmap[i];
5058     ierr = ISCreateGeneral(PETSC_COMM_SELF,ncols,idx,PETSC_OWN_POINTER,&iscola);CHKERRQ(ierr);
5059   } else {
5060     iscola = *col;
5061   }
5062   if (scall != MAT_INITIAL_MATRIX) {
5063     ierr    = PetscMalloc(sizeof(Mat),&aloc);CHKERRQ(ierr);
5064     aloc[0] = *A_loc;
5065   }
5066   ierr   = MatGetSubMatrices(A,1,&isrowa,&iscola,scall,&aloc);CHKERRQ(ierr);
5067   *A_loc = aloc[0];
5068   ierr   = PetscFree(aloc);CHKERRQ(ierr);
5069   if (!row) {
5070     ierr = ISDestroy(&isrowa);CHKERRQ(ierr);
5071   }
5072   if (!col) {
5073     ierr = ISDestroy(&iscola);CHKERRQ(ierr);
5074   }
5075   ierr = PetscLogEventEnd(MAT_Getlocalmatcondensed,A,0,0,0);CHKERRQ(ierr);
5076   PetscFunctionReturn(0);
5077 }
5078 
5079 #undef __FUNCT__
5080 #define __FUNCT__ "MatGetBrowsOfAcols"
5081 /*@C
5082     MatGetBrowsOfAcols - Creates a SeqAIJ matrix by taking rows of B that equal to nonzero columns of local A
5083 
5084     Collective on Mat
5085 
5086    Input Parameters:
5087 +    A,B - the matrices in mpiaij format
5088 .    scall - either MAT_INITIAL_MATRIX or MAT_REUSE_MATRIX
5089 -    rowb, colb - index sets of rows and columns of B to extract (or NULL)
5090 
5091    Output Parameter:
5092 +    rowb, colb - index sets of rows and columns of B to extract
5093 -    B_seq - the sequential matrix generated
5094 
5095     Level: developer
5096 
5097 @*/
5098 PetscErrorCode  MatGetBrowsOfAcols(Mat A,Mat B,MatReuse scall,IS *rowb,IS *colb,Mat *B_seq)
5099 {
5100   Mat_MPIAIJ     *a=(Mat_MPIAIJ*)A->data;
5101   PetscErrorCode ierr;
5102   PetscInt       *idx,i,start,ncols,nzA,nzB,*cmap,imark;
5103   IS             isrowb,iscolb;
5104   Mat            *bseq=NULL;
5105 
5106   PetscFunctionBegin;
5107   if (A->cmap->rstart != B->rmap->rstart || A->cmap->rend != B->rmap->rend) {
5108     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);
5109   }
5110   ierr = PetscLogEventBegin(MAT_GetBrowsOfAcols,A,B,0,0);CHKERRQ(ierr);
5111 
5112   if (scall == MAT_INITIAL_MATRIX) {
5113     start = A->cmap->rstart;
5114     cmap  = a->garray;
5115     nzA   = a->A->cmap->n;
5116     nzB   = a->B->cmap->n;
5117     ierr  = PetscMalloc1((nzA+nzB), &idx);CHKERRQ(ierr);
5118     ncols = 0;
5119     for (i=0; i<nzB; i++) {  /* row < local row index */
5120       if (cmap[i] < start) idx[ncols++] = cmap[i];
5121       else break;
5122     }
5123     imark = i;
5124     for (i=0; i<nzA; i++) idx[ncols++] = start + i;  /* local rows */
5125     for (i=imark; i<nzB; i++) idx[ncols++] = cmap[i]; /* row > local row index */
5126     ierr = ISCreateGeneral(PETSC_COMM_SELF,ncols,idx,PETSC_OWN_POINTER,&isrowb);CHKERRQ(ierr);
5127     ierr = ISCreateStride(PETSC_COMM_SELF,B->cmap->N,0,1,&iscolb);CHKERRQ(ierr);
5128   } else {
5129     if (!rowb || !colb) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_SUP,"IS rowb and colb must be provided for MAT_REUSE_MATRIX");
5130     isrowb  = *rowb; iscolb = *colb;
5131     ierr    = PetscMalloc(sizeof(Mat),&bseq);CHKERRQ(ierr);
5132     bseq[0] = *B_seq;
5133   }
5134   ierr   = MatGetSubMatrices(B,1,&isrowb,&iscolb,scall,&bseq);CHKERRQ(ierr);
5135   *B_seq = bseq[0];
5136   ierr   = PetscFree(bseq);CHKERRQ(ierr);
5137   if (!rowb) {
5138     ierr = ISDestroy(&isrowb);CHKERRQ(ierr);
5139   } else {
5140     *rowb = isrowb;
5141   }
5142   if (!colb) {
5143     ierr = ISDestroy(&iscolb);CHKERRQ(ierr);
5144   } else {
5145     *colb = iscolb;
5146   }
5147   ierr = PetscLogEventEnd(MAT_GetBrowsOfAcols,A,B,0,0);CHKERRQ(ierr);
5148   PetscFunctionReturn(0);
5149 }
5150 
5151 #undef __FUNCT__
5152 #define __FUNCT__ "MatGetBrowsOfAoCols_MPIAIJ"
5153 /*
5154     MatGetBrowsOfAoCols_MPIAIJ - Creates a SeqAIJ matrix by taking rows of B that equal to nonzero columns
5155     of the OFF-DIAGONAL portion of local A
5156 
5157     Collective on Mat
5158 
5159    Input Parameters:
5160 +    A,B - the matrices in mpiaij format
5161 -    scall - either MAT_INITIAL_MATRIX or MAT_REUSE_MATRIX
5162 
5163    Output Parameter:
5164 +    startsj_s - starting point in B's sending j-arrays, saved for MAT_REUSE (or NULL)
5165 .    startsj_r - starting point in B's receiving j-arrays, saved for MAT_REUSE (or NULL)
5166 .    bufa_ptr - array for sending matrix values, saved for MAT_REUSE (or NULL)
5167 -    B_oth - the sequential matrix generated with size aBn=a->B->cmap->n by B->cmap->N
5168 
5169     Level: developer
5170 
5171 */
5172 PetscErrorCode  MatGetBrowsOfAoCols_MPIAIJ(Mat A,Mat B,MatReuse scall,PetscInt **startsj_s,PetscInt **startsj_r,MatScalar **bufa_ptr,Mat *B_oth)
5173 {
5174   VecScatter_MPI_General *gen_to,*gen_from;
5175   PetscErrorCode         ierr;
5176   Mat_MPIAIJ             *a=(Mat_MPIAIJ*)A->data;
5177   Mat_SeqAIJ             *b_oth;
5178   VecScatter             ctx =a->Mvctx;
5179   MPI_Comm               comm;
5180   PetscMPIInt            *rprocs,*sprocs,tag=((PetscObject)ctx)->tag,rank;
5181   PetscInt               *rowlen,*bufj,*bufJ,ncols,aBn=a->B->cmap->n,row,*b_othi,*b_othj;
5182   PetscScalar            *rvalues,*svalues;
5183   MatScalar              *b_otha,*bufa,*bufA;
5184   PetscInt               i,j,k,l,ll,nrecvs,nsends,nrows,*srow,*rstarts,*rstartsj = 0,*sstarts,*sstartsj,len;
5185   MPI_Request            *rwaits = NULL,*swaits = NULL;
5186   MPI_Status             *sstatus,rstatus;
5187   PetscMPIInt            jj,size;
5188   PetscInt               *cols,sbs,rbs;
5189   PetscScalar            *vals;
5190 
5191   PetscFunctionBegin;
5192   ierr = PetscObjectGetComm((PetscObject)A,&comm);CHKERRQ(ierr);
5193   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
5194   if (size == 1) PetscFunctionReturn(0);
5195 
5196   if (A->cmap->rstart != B->rmap->rstart || A->cmap->rend != B->rmap->rend) {
5197     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);
5198   }
5199   ierr = PetscLogEventBegin(MAT_GetBrowsOfAocols,A,B,0,0);CHKERRQ(ierr);
5200   ierr = MPI_Comm_rank(comm,&rank);CHKERRQ(ierr);
5201 
5202   gen_to   = (VecScatter_MPI_General*)ctx->todata;
5203   gen_from = (VecScatter_MPI_General*)ctx->fromdata;
5204   rvalues  = gen_from->values; /* holds the length of receiving row */
5205   svalues  = gen_to->values;   /* holds the length of sending row */
5206   nrecvs   = gen_from->n;
5207   nsends   = gen_to->n;
5208 
5209   ierr    = PetscMalloc2(nrecvs,&rwaits,nsends,&swaits);CHKERRQ(ierr);
5210   srow    = gen_to->indices;    /* local row index to be sent */
5211   sstarts = gen_to->starts;
5212   sprocs  = gen_to->procs;
5213   sstatus = gen_to->sstatus;
5214   sbs     = gen_to->bs;
5215   rstarts = gen_from->starts;
5216   rprocs  = gen_from->procs;
5217   rbs     = gen_from->bs;
5218 
5219   if (!startsj_s || !bufa_ptr) scall = MAT_INITIAL_MATRIX;
5220   if (scall == MAT_INITIAL_MATRIX) {
5221     /* i-array */
5222     /*---------*/
5223     /*  post receives */
5224     for (i=0; i<nrecvs; i++) {
5225       rowlen = (PetscInt*)rvalues + rstarts[i]*rbs;
5226       nrows  = (rstarts[i+1]-rstarts[i])*rbs; /* num of indices to be received */
5227       ierr   = MPI_Irecv(rowlen,nrows,MPIU_INT,rprocs[i],tag,comm,rwaits+i);CHKERRQ(ierr);
5228     }
5229 
5230     /* pack the outgoing message */
5231     ierr = PetscMalloc2(nsends+1,&sstartsj,nrecvs+1,&rstartsj);CHKERRQ(ierr);
5232 
5233     sstartsj[0] = 0;
5234     rstartsj[0] = 0;
5235     len         = 0; /* total length of j or a array to be sent */
5236     k           = 0;
5237     for (i=0; i<nsends; i++) {
5238       rowlen = (PetscInt*)svalues + sstarts[i]*sbs;
5239       nrows  = sstarts[i+1]-sstarts[i]; /* num of block rows */
5240       for (j=0; j<nrows; j++) {
5241         row = srow[k] + B->rmap->range[rank]; /* global row idx */
5242         for (l=0; l<sbs; l++) {
5243           ierr = MatGetRow_MPIAIJ(B,row+l,&ncols,NULL,NULL);CHKERRQ(ierr); /* rowlength */
5244 
5245           rowlen[j*sbs+l] = ncols;
5246 
5247           len += ncols;
5248           ierr = MatRestoreRow_MPIAIJ(B,row+l,&ncols,NULL,NULL);CHKERRQ(ierr);
5249         }
5250         k++;
5251       }
5252       ierr = MPI_Isend(rowlen,nrows*sbs,MPIU_INT,sprocs[i],tag,comm,swaits+i);CHKERRQ(ierr);
5253 
5254       sstartsj[i+1] = len;  /* starting point of (i+1)-th outgoing msg in bufj and bufa */
5255     }
5256     /* recvs and sends of i-array are completed */
5257     i = nrecvs;
5258     while (i--) {
5259       ierr = MPI_Waitany(nrecvs,rwaits,&jj,&rstatus);CHKERRQ(ierr);
5260     }
5261     if (nsends) {ierr = MPI_Waitall(nsends,swaits,sstatus);CHKERRQ(ierr);}
5262 
5263     /* allocate buffers for sending j and a arrays */
5264     ierr = PetscMalloc1((len+1),&bufj);CHKERRQ(ierr);
5265     ierr = PetscMalloc1((len+1),&bufa);CHKERRQ(ierr);
5266 
5267     /* create i-array of B_oth */
5268     ierr = PetscMalloc1((aBn+2),&b_othi);CHKERRQ(ierr);
5269 
5270     b_othi[0] = 0;
5271     len       = 0; /* total length of j or a array to be received */
5272     k         = 0;
5273     for (i=0; i<nrecvs; i++) {
5274       rowlen = (PetscInt*)rvalues + rstarts[i]*rbs;
5275       nrows  = rbs*(rstarts[i+1]-rstarts[i]); /* num of rows to be recieved */
5276       for (j=0; j<nrows; j++) {
5277         b_othi[k+1] = b_othi[k] + rowlen[j];
5278         len        += rowlen[j]; k++;
5279       }
5280       rstartsj[i+1] = len; /* starting point of (i+1)-th incoming msg in bufj and bufa */
5281     }
5282 
5283     /* allocate space for j and a arrrays of B_oth */
5284     ierr = PetscMalloc1((b_othi[aBn]+1),&b_othj);CHKERRQ(ierr);
5285     ierr = PetscMalloc1((b_othi[aBn]+1),&b_otha);CHKERRQ(ierr);
5286 
5287     /* j-array */
5288     /*---------*/
5289     /*  post receives of j-array */
5290     for (i=0; i<nrecvs; i++) {
5291       nrows = rstartsj[i+1]-rstartsj[i]; /* length of the msg received */
5292       ierr  = MPI_Irecv(b_othj+rstartsj[i],nrows,MPIU_INT,rprocs[i],tag,comm,rwaits+i);CHKERRQ(ierr);
5293     }
5294 
5295     /* pack the outgoing message j-array */
5296     k = 0;
5297     for (i=0; i<nsends; i++) {
5298       nrows = sstarts[i+1]-sstarts[i]; /* num of block rows */
5299       bufJ  = bufj+sstartsj[i];
5300       for (j=0; j<nrows; j++) {
5301         row = srow[k++] + B->rmap->range[rank];  /* global row idx */
5302         for (ll=0; ll<sbs; ll++) {
5303           ierr = MatGetRow_MPIAIJ(B,row+ll,&ncols,&cols,NULL);CHKERRQ(ierr);
5304           for (l=0; l<ncols; l++) {
5305             *bufJ++ = cols[l];
5306           }
5307           ierr = MatRestoreRow_MPIAIJ(B,row+ll,&ncols,&cols,NULL);CHKERRQ(ierr);
5308         }
5309       }
5310       ierr = MPI_Isend(bufj+sstartsj[i],sstartsj[i+1]-sstartsj[i],MPIU_INT,sprocs[i],tag,comm,swaits+i);CHKERRQ(ierr);
5311     }
5312 
5313     /* recvs and sends of j-array are completed */
5314     i = nrecvs;
5315     while (i--) {
5316       ierr = MPI_Waitany(nrecvs,rwaits,&jj,&rstatus);CHKERRQ(ierr);
5317     }
5318     if (nsends) {ierr = MPI_Waitall(nsends,swaits,sstatus);CHKERRQ(ierr);}
5319   } else if (scall == MAT_REUSE_MATRIX) {
5320     sstartsj = *startsj_s;
5321     rstartsj = *startsj_r;
5322     bufa     = *bufa_ptr;
5323     b_oth    = (Mat_SeqAIJ*)(*B_oth)->data;
5324     b_otha   = b_oth->a;
5325   } else SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE, "Matrix P does not posses an object container");
5326 
5327   /* a-array */
5328   /*---------*/
5329   /*  post receives of a-array */
5330   for (i=0; i<nrecvs; i++) {
5331     nrows = rstartsj[i+1]-rstartsj[i]; /* length of the msg received */
5332     ierr  = MPI_Irecv(b_otha+rstartsj[i],nrows,MPIU_SCALAR,rprocs[i],tag,comm,rwaits+i);CHKERRQ(ierr);
5333   }
5334 
5335   /* pack the outgoing message a-array */
5336   k = 0;
5337   for (i=0; i<nsends; i++) {
5338     nrows = sstarts[i+1]-sstarts[i]; /* num of block rows */
5339     bufA  = bufa+sstartsj[i];
5340     for (j=0; j<nrows; j++) {
5341       row = srow[k++] + B->rmap->range[rank];  /* global row idx */
5342       for (ll=0; ll<sbs; ll++) {
5343         ierr = MatGetRow_MPIAIJ(B,row+ll,&ncols,NULL,&vals);CHKERRQ(ierr);
5344         for (l=0; l<ncols; l++) {
5345           *bufA++ = vals[l];
5346         }
5347         ierr = MatRestoreRow_MPIAIJ(B,row+ll,&ncols,NULL,&vals);CHKERRQ(ierr);
5348       }
5349     }
5350     ierr = MPI_Isend(bufa+sstartsj[i],sstartsj[i+1]-sstartsj[i],MPIU_SCALAR,sprocs[i],tag,comm,swaits+i);CHKERRQ(ierr);
5351   }
5352   /* recvs and sends of a-array are completed */
5353   i = nrecvs;
5354   while (i--) {
5355     ierr = MPI_Waitany(nrecvs,rwaits,&jj,&rstatus);CHKERRQ(ierr);
5356   }
5357   if (nsends) {ierr = MPI_Waitall(nsends,swaits,sstatus);CHKERRQ(ierr);}
5358   ierr = PetscFree2(rwaits,swaits);CHKERRQ(ierr);
5359 
5360   if (scall == MAT_INITIAL_MATRIX) {
5361     /* put together the new matrix */
5362     ierr = MatCreateSeqAIJWithArrays(PETSC_COMM_SELF,aBn,B->cmap->N,b_othi,b_othj,b_otha,B_oth);CHKERRQ(ierr);
5363 
5364     /* MatCreateSeqAIJWithArrays flags matrix so PETSc doesn't free the user's arrays. */
5365     /* Since these are PETSc arrays, change flags to free them as necessary. */
5366     b_oth          = (Mat_SeqAIJ*)(*B_oth)->data;
5367     b_oth->free_a  = PETSC_TRUE;
5368     b_oth->free_ij = PETSC_TRUE;
5369     b_oth->nonew   = 0;
5370 
5371     ierr = PetscFree(bufj);CHKERRQ(ierr);
5372     if (!startsj_s || !bufa_ptr) {
5373       ierr = PetscFree2(sstartsj,rstartsj);CHKERRQ(ierr);
5374       ierr = PetscFree(bufa_ptr);CHKERRQ(ierr);
5375     } else {
5376       *startsj_s = sstartsj;
5377       *startsj_r = rstartsj;
5378       *bufa_ptr  = bufa;
5379     }
5380   }
5381   ierr = PetscLogEventEnd(MAT_GetBrowsOfAocols,A,B,0,0);CHKERRQ(ierr);
5382   PetscFunctionReturn(0);
5383 }
5384 
5385 #undef __FUNCT__
5386 #define __FUNCT__ "MatGetCommunicationStructs"
5387 /*@C
5388   MatGetCommunicationStructs - Provides access to the communication structures used in matrix-vector multiplication.
5389 
5390   Not Collective
5391 
5392   Input Parameters:
5393 . A - The matrix in mpiaij format
5394 
5395   Output Parameter:
5396 + lvec - The local vector holding off-process values from the argument to a matrix-vector product
5397 . colmap - A map from global column index to local index into lvec
5398 - multScatter - A scatter from the argument of a matrix-vector product to lvec
5399 
5400   Level: developer
5401 
5402 @*/
5403 #if defined(PETSC_USE_CTABLE)
5404 PetscErrorCode  MatGetCommunicationStructs(Mat A, Vec *lvec, PetscTable *colmap, VecScatter *multScatter)
5405 #else
5406 PetscErrorCode  MatGetCommunicationStructs(Mat A, Vec *lvec, PetscInt *colmap[], VecScatter *multScatter)
5407 #endif
5408 {
5409   Mat_MPIAIJ *a;
5410 
5411   PetscFunctionBegin;
5412   PetscValidHeaderSpecific(A, MAT_CLASSID, 1);
5413   PetscValidPointer(lvec, 2);
5414   PetscValidPointer(colmap, 3);
5415   PetscValidPointer(multScatter, 4);
5416   a = (Mat_MPIAIJ*) A->data;
5417   if (lvec) *lvec = a->lvec;
5418   if (colmap) *colmap = a->colmap;
5419   if (multScatter) *multScatter = a->Mvctx;
5420   PetscFunctionReturn(0);
5421 }
5422 
5423 PETSC_EXTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJCRL(Mat,MatType,MatReuse,Mat*);
5424 PETSC_EXTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJPERM(Mat,MatType,MatReuse,Mat*);
5425 PETSC_EXTERN PetscErrorCode MatConvert_MPIAIJ_MPISBAIJ(Mat,MatType,MatReuse,Mat*);
5426 #if defined(PETSC_HAVE_ELEMENTAL)
5427 PETSC_EXTERN PetscErrorCode MatConvert_MPIAIJ_Elemental(Mat,MatType,MatReuse,Mat*);
5428 #endif
5429 
5430 #undef __FUNCT__
5431 #define __FUNCT__ "MatMatMultNumeric_MPIDense_MPIAIJ"
5432 /*
5433     Computes (B'*A')' since computing B*A directly is untenable
5434 
5435                n                       p                          p
5436         (              )       (              )         (                  )
5437       m (      A       )  *  n (       B      )   =   m (         C        )
5438         (              )       (              )         (                  )
5439 
5440 */
5441 PetscErrorCode MatMatMultNumeric_MPIDense_MPIAIJ(Mat A,Mat B,Mat C)
5442 {
5443   PetscErrorCode ierr;
5444   Mat            At,Bt,Ct;
5445 
5446   PetscFunctionBegin;
5447   ierr = MatTranspose(A,MAT_INITIAL_MATRIX,&At);CHKERRQ(ierr);
5448   ierr = MatTranspose(B,MAT_INITIAL_MATRIX,&Bt);CHKERRQ(ierr);
5449   ierr = MatMatMult(Bt,At,MAT_INITIAL_MATRIX,1.0,&Ct);CHKERRQ(ierr);
5450   ierr = MatDestroy(&At);CHKERRQ(ierr);
5451   ierr = MatDestroy(&Bt);CHKERRQ(ierr);
5452   ierr = MatTranspose(Ct,MAT_REUSE_MATRIX,&C);CHKERRQ(ierr);
5453   ierr = MatDestroy(&Ct);CHKERRQ(ierr);
5454   PetscFunctionReturn(0);
5455 }
5456 
5457 #undef __FUNCT__
5458 #define __FUNCT__ "MatMatMultSymbolic_MPIDense_MPIAIJ"
5459 PetscErrorCode MatMatMultSymbolic_MPIDense_MPIAIJ(Mat A,Mat B,PetscReal fill,Mat *C)
5460 {
5461   PetscErrorCode ierr;
5462   PetscInt       m=A->rmap->n,n=B->cmap->n;
5463   Mat            Cmat;
5464 
5465   PetscFunctionBegin;
5466   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);
5467   ierr = MatCreate(PetscObjectComm((PetscObject)A),&Cmat);CHKERRQ(ierr);
5468   ierr = MatSetSizes(Cmat,m,n,PETSC_DETERMINE,PETSC_DETERMINE);CHKERRQ(ierr);
5469   ierr = MatSetBlockSizesFromMats(Cmat,A,B);CHKERRQ(ierr);
5470   ierr = MatSetType(Cmat,MATMPIDENSE);CHKERRQ(ierr);
5471   ierr = MatMPIDenseSetPreallocation(Cmat,NULL);CHKERRQ(ierr);
5472   ierr = MatAssemblyBegin(Cmat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
5473   ierr = MatAssemblyEnd(Cmat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
5474 
5475   Cmat->ops->matmultnumeric = MatMatMultNumeric_MPIDense_MPIAIJ;
5476 
5477   *C = Cmat;
5478   PetscFunctionReturn(0);
5479 }
5480 
5481 /* ----------------------------------------------------------------*/
5482 #undef __FUNCT__
5483 #define __FUNCT__ "MatMatMult_MPIDense_MPIAIJ"
5484 PetscErrorCode MatMatMult_MPIDense_MPIAIJ(Mat A,Mat B,MatReuse scall,PetscReal fill,Mat *C)
5485 {
5486   PetscErrorCode ierr;
5487 
5488   PetscFunctionBegin;
5489   if (scall == MAT_INITIAL_MATRIX) {
5490     ierr = PetscLogEventBegin(MAT_MatMultSymbolic,A,B,0,0);CHKERRQ(ierr);
5491     ierr = MatMatMultSymbolic_MPIDense_MPIAIJ(A,B,fill,C);CHKERRQ(ierr);
5492     ierr = PetscLogEventEnd(MAT_MatMultSymbolic,A,B,0,0);CHKERRQ(ierr);
5493   }
5494   ierr = PetscLogEventBegin(MAT_MatMultNumeric,A,B,0,0);CHKERRQ(ierr);
5495   ierr = MatMatMultNumeric_MPIDense_MPIAIJ(A,B,*C);CHKERRQ(ierr);
5496   ierr = PetscLogEventEnd(MAT_MatMultNumeric,A,B,0,0);CHKERRQ(ierr);
5497   PetscFunctionReturn(0);
5498 }
5499 
5500 #if defined(PETSC_HAVE_MUMPS)
5501 PETSC_EXTERN PetscErrorCode MatGetFactor_aij_mumps(Mat,MatFactorType,Mat*);
5502 #endif
5503 #if defined(PETSC_HAVE_PASTIX)
5504 PETSC_EXTERN PetscErrorCode MatGetFactor_mpiaij_pastix(Mat,MatFactorType,Mat*);
5505 #endif
5506 #if defined(PETSC_HAVE_SUPERLU_DIST)
5507 PETSC_EXTERN PetscErrorCode MatGetFactor_mpiaij_superlu_dist(Mat,MatFactorType,Mat*);
5508 #endif
5509 #if defined(PETSC_HAVE_CLIQUE)
5510 PETSC_EXTERN PetscErrorCode MatGetFactor_aij_clique(Mat,MatFactorType,Mat*);
5511 #endif
5512 
5513 /*MC
5514    MATMPIAIJ - MATMPIAIJ = "mpiaij" - A matrix type to be used for parallel sparse matrices.
5515 
5516    Options Database Keys:
5517 . -mat_type mpiaij - sets the matrix type to "mpiaij" during a call to MatSetFromOptions()
5518 
5519   Level: beginner
5520 
5521 .seealso: MatCreateAIJ()
5522 M*/
5523 
5524 #undef __FUNCT__
5525 #define __FUNCT__ "MatCreate_MPIAIJ"
5526 PETSC_EXTERN PetscErrorCode MatCreate_MPIAIJ(Mat B)
5527 {
5528   Mat_MPIAIJ     *b;
5529   PetscErrorCode ierr;
5530   PetscMPIInt    size;
5531 
5532   PetscFunctionBegin;
5533   ierr = MPI_Comm_size(PetscObjectComm((PetscObject)B),&size);CHKERRQ(ierr);
5534 
5535   ierr          = PetscNewLog(B,&b);CHKERRQ(ierr);
5536   B->data       = (void*)b;
5537   ierr          = PetscMemcpy(B->ops,&MatOps_Values,sizeof(struct _MatOps));CHKERRQ(ierr);
5538   B->assembled  = PETSC_FALSE;
5539   B->insertmode = NOT_SET_VALUES;
5540   b->size       = size;
5541 
5542   ierr = MPI_Comm_rank(PetscObjectComm((PetscObject)B),&b->rank);CHKERRQ(ierr);
5543 
5544   /* build cache for off array entries formed */
5545   ierr = MatStashCreate_Private(PetscObjectComm((PetscObject)B),1,&B->stash);CHKERRQ(ierr);
5546 
5547   b->donotstash  = PETSC_FALSE;
5548   b->colmap      = 0;
5549   b->garray      = 0;
5550   b->roworiented = PETSC_TRUE;
5551 
5552   /* stuff used for matrix vector multiply */
5553   b->lvec  = NULL;
5554   b->Mvctx = NULL;
5555 
5556   /* stuff for MatGetRow() */
5557   b->rowindices   = 0;
5558   b->rowvalues    = 0;
5559   b->getrowactive = PETSC_FALSE;
5560 
5561   /* flexible pointer used in CUSP/CUSPARSE classes */
5562   b->spptr = NULL;
5563 
5564 #if defined(PETSC_HAVE_MUMPS)
5565   ierr = PetscObjectComposeFunction((PetscObject)B,"MatGetFactor_mumps_C",MatGetFactor_aij_mumps);CHKERRQ(ierr);
5566 #endif
5567 #if defined(PETSC_HAVE_PASTIX)
5568   ierr = PetscObjectComposeFunction((PetscObject)B,"MatGetFactor_pastix_C",MatGetFactor_mpiaij_pastix);CHKERRQ(ierr);
5569 #endif
5570 #if defined(PETSC_HAVE_SUPERLU_DIST)
5571   ierr = PetscObjectComposeFunction((PetscObject)B,"MatGetFactor_superlu_dist_C",MatGetFactor_mpiaij_superlu_dist);CHKERRQ(ierr);
5572 #endif
5573 #if defined(PETSC_HAVE_CLIQUE)
5574   ierr = PetscObjectComposeFunction((PetscObject)B,"MatGetFactor_clique_C",MatGetFactor_aij_clique);CHKERRQ(ierr);
5575 #endif
5576   ierr = PetscObjectComposeFunction((PetscObject)B,"MatStoreValues_C",MatStoreValues_MPIAIJ);CHKERRQ(ierr);
5577   ierr = PetscObjectComposeFunction((PetscObject)B,"MatRetrieveValues_C",MatRetrieveValues_MPIAIJ);CHKERRQ(ierr);
5578   ierr = PetscObjectComposeFunction((PetscObject)B,"MatGetDiagonalBlock_C",MatGetDiagonalBlock_MPIAIJ);CHKERRQ(ierr);
5579   ierr = PetscObjectComposeFunction((PetscObject)B,"MatIsTranspose_C",MatIsTranspose_MPIAIJ);CHKERRQ(ierr);
5580   ierr = PetscObjectComposeFunction((PetscObject)B,"MatMPIAIJSetPreallocation_C",MatMPIAIJSetPreallocation_MPIAIJ);CHKERRQ(ierr);
5581   ierr = PetscObjectComposeFunction((PetscObject)B,"MatMPIAIJSetPreallocationCSR_C",MatMPIAIJSetPreallocationCSR_MPIAIJ);CHKERRQ(ierr);
5582   ierr = PetscObjectComposeFunction((PetscObject)B,"MatDiagonalScaleLocal_C",MatDiagonalScaleLocal_MPIAIJ);CHKERRQ(ierr);
5583   ierr = PetscObjectComposeFunction((PetscObject)B,"MatConvert_mpiaij_mpiaijperm_C",MatConvert_MPIAIJ_MPIAIJPERM);CHKERRQ(ierr);
5584   ierr = PetscObjectComposeFunction((PetscObject)B,"MatConvert_mpiaij_mpiaijcrl_C",MatConvert_MPIAIJ_MPIAIJCRL);CHKERRQ(ierr);
5585   ierr = PetscObjectComposeFunction((PetscObject)B,"MatConvert_mpiaij_mpisbaij_C",MatConvert_MPIAIJ_MPISBAIJ);CHKERRQ(ierr);
5586 #if defined(PETSC_HAVE_ELEMENTAL)
5587   ierr = PetscObjectComposeFunction((PetscObject)B,"MatConvert_mpiaij_elemental_C",MatConvert_MPIAIJ_Elemental);CHKERRQ(ierr);
5588 #endif
5589   ierr = PetscObjectComposeFunction((PetscObject)B,"MatMatMult_mpidense_mpiaij_C",MatMatMult_MPIDense_MPIAIJ);CHKERRQ(ierr);
5590   ierr = PetscObjectComposeFunction((PetscObject)B,"MatMatMultSymbolic_mpidense_mpiaij_C",MatMatMultSymbolic_MPIDense_MPIAIJ);CHKERRQ(ierr);
5591   ierr = PetscObjectComposeFunction((PetscObject)B,"MatMatMultNumeric_mpidense_mpiaij_C",MatMatMultNumeric_MPIDense_MPIAIJ);CHKERRQ(ierr);
5592   ierr = PetscObjectChangeTypeName((PetscObject)B,MATMPIAIJ);CHKERRQ(ierr);
5593   PetscFunctionReturn(0);
5594 }
5595 
5596 #undef __FUNCT__
5597 #define __FUNCT__ "MatCreateMPIAIJWithSplitArrays"
5598 /*@
5599      MatCreateMPIAIJWithSplitArrays - creates a MPI AIJ matrix using arrays that contain the "diagonal"
5600          and "off-diagonal" part of the matrix in CSR format.
5601 
5602    Collective on MPI_Comm
5603 
5604    Input Parameters:
5605 +  comm - MPI communicator
5606 .  m - number of local rows (Cannot be PETSC_DECIDE)
5607 .  n - This value should be the same as the local size used in creating the
5608        x vector for the matrix-vector product y = Ax. (or PETSC_DECIDE to have
5609        calculated if N is given) For square matrices n is almost always m.
5610 .  M - number of global rows (or PETSC_DETERMINE to have calculated if m is given)
5611 .  N - number of global columns (or PETSC_DETERMINE to have calculated if n is given)
5612 .   i - row indices for "diagonal" portion of matrix
5613 .   j - column indices
5614 .   a - matrix values
5615 .   oi - row indices for "off-diagonal" portion of matrix
5616 .   oj - column indices
5617 -   oa - matrix values
5618 
5619    Output Parameter:
5620 .   mat - the matrix
5621 
5622    Level: advanced
5623 
5624    Notes:
5625        The i, j, and a arrays ARE NOT copied by this routine into the internal format used by PETSc. The user
5626        must free the arrays once the matrix has been destroyed and not before.
5627 
5628        The i and j indices are 0 based
5629 
5630        See MatCreateAIJ() for the definition of "diagonal" and "off-diagonal" portion of the matrix
5631 
5632        This sets local rows and cannot be used to set off-processor values.
5633 
5634        Use of this routine is discouraged because it is inflexible and cumbersome to use. It is extremely rare that a
5635        legacy application natively assembles into exactly this split format. The code to do so is nontrivial and does
5636        not easily support in-place reassembly. It is recommended to use MatSetValues() (or a variant thereof) because
5637        the resulting assembly is easier to implement, will work with any matrix format, and the user does not have to
5638        keep track of the underlying array. Use MatSetOption(A,MAT_IGNORE_OFF_PROC_ENTRIES,PETSC_TRUE) to disable all
5639        communication if it is known that only local entries will be set.
5640 
5641 .keywords: matrix, aij, compressed row, sparse, parallel
5642 
5643 .seealso: MatCreate(), MatCreateSeqAIJ(), MatSetValues(), MatMPIAIJSetPreallocation(), MatMPIAIJSetPreallocationCSR(),
5644           MPIAIJ, MatCreateAIJ(), MatCreateMPIAIJWithArrays()
5645 @*/
5646 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)
5647 {
5648   PetscErrorCode ierr;
5649   Mat_MPIAIJ     *maij;
5650 
5651   PetscFunctionBegin;
5652   if (m < 0) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"local number of rows (m) cannot be PETSC_DECIDE, or negative");
5653   if (i[0]) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"i (row indices) must start with 0");
5654   if (oi[0]) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"oi (row indices) must start with 0");
5655   ierr = MatCreate(comm,mat);CHKERRQ(ierr);
5656   ierr = MatSetSizes(*mat,m,n,M,N);CHKERRQ(ierr);
5657   ierr = MatSetType(*mat,MATMPIAIJ);CHKERRQ(ierr);
5658   maij = (Mat_MPIAIJ*) (*mat)->data;
5659 
5660   (*mat)->preallocated = PETSC_TRUE;
5661 
5662   ierr = PetscLayoutSetUp((*mat)->rmap);CHKERRQ(ierr);
5663   ierr = PetscLayoutSetUp((*mat)->cmap);CHKERRQ(ierr);
5664 
5665   ierr = MatCreateSeqAIJWithArrays(PETSC_COMM_SELF,m,n,i,j,a,&maij->A);CHKERRQ(ierr);
5666   ierr = MatCreateSeqAIJWithArrays(PETSC_COMM_SELF,m,(*mat)->cmap->N,oi,oj,oa,&maij->B);CHKERRQ(ierr);
5667 
5668   ierr = MatAssemblyBegin(maij->A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
5669   ierr = MatAssemblyEnd(maij->A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
5670   ierr = MatAssemblyBegin(maij->B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
5671   ierr = MatAssemblyEnd(maij->B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
5672 
5673   ierr = MatAssemblyBegin(*mat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
5674   ierr = MatAssemblyEnd(*mat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
5675   ierr = MatSetOption(*mat,MAT_NEW_NONZERO_LOCATION_ERR,PETSC_TRUE);CHKERRQ(ierr);
5676   PetscFunctionReturn(0);
5677 }
5678 
5679 /*
5680     Special version for direct calls from Fortran
5681 */
5682 #include <petsc-private/fortranimpl.h>
5683 
5684 #if defined(PETSC_HAVE_FORTRAN_CAPS)
5685 #define matsetvaluesmpiaij_ MATSETVALUESMPIAIJ
5686 #elif !defined(PETSC_HAVE_FORTRAN_UNDERSCORE)
5687 #define matsetvaluesmpiaij_ matsetvaluesmpiaij
5688 #endif
5689 
5690 /* Change these macros so can be used in void function */
5691 #undef CHKERRQ
5692 #define CHKERRQ(ierr) CHKERRABORT(PETSC_COMM_WORLD,ierr)
5693 #undef SETERRQ2
5694 #define SETERRQ2(comm,ierr,b,c,d) CHKERRABORT(comm,ierr)
5695 #undef SETERRQ3
5696 #define SETERRQ3(comm,ierr,b,c,d,e) CHKERRABORT(comm,ierr)
5697 #undef SETERRQ
5698 #define SETERRQ(c,ierr,b) CHKERRABORT(c,ierr)
5699 
5700 #undef __FUNCT__
5701 #define __FUNCT__ "matsetvaluesmpiaij_"
5702 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)
5703 {
5704   Mat            mat  = *mmat;
5705   PetscInt       m    = *mm, n = *mn;
5706   InsertMode     addv = *maddv;
5707   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
5708   PetscScalar    value;
5709   PetscErrorCode ierr;
5710 
5711   MatCheckPreallocated(mat,1);
5712   if (mat->insertmode == NOT_SET_VALUES) mat->insertmode = addv;
5713 
5714 #if defined(PETSC_USE_DEBUG)
5715   else if (mat->insertmode != addv) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"Cannot mix add values and insert values");
5716 #endif
5717   {
5718     PetscInt  i,j,rstart  = mat->rmap->rstart,rend = mat->rmap->rend;
5719     PetscInt  cstart      = mat->cmap->rstart,cend = mat->cmap->rend,row,col;
5720     PetscBool roworiented = aij->roworiented;
5721 
5722     /* Some Variables required in the macro */
5723     Mat        A                 = aij->A;
5724     Mat_SeqAIJ *a                = (Mat_SeqAIJ*)A->data;
5725     PetscInt   *aimax            = a->imax,*ai = a->i,*ailen = a->ilen,*aj = a->j;
5726     MatScalar  *aa               = a->a;
5727     PetscBool  ignorezeroentries = (((a->ignorezeroentries)&&(addv==ADD_VALUES)) ? PETSC_TRUE : PETSC_FALSE);
5728     Mat        B                 = aij->B;
5729     Mat_SeqAIJ *b                = (Mat_SeqAIJ*)B->data;
5730     PetscInt   *bimax            = b->imax,*bi = b->i,*bilen = b->ilen,*bj = b->j,bm = aij->B->rmap->n,am = aij->A->rmap->n;
5731     MatScalar  *ba               = b->a;
5732 
5733     PetscInt  *rp1,*rp2,ii,nrow1,nrow2,_i,rmax1,rmax2,N,low1,high1,low2,high2,t,lastcol1,lastcol2;
5734     PetscInt  nonew = a->nonew;
5735     MatScalar *ap1,*ap2;
5736 
5737     PetscFunctionBegin;
5738     for (i=0; i<m; i++) {
5739       if (im[i] < 0) continue;
5740 #if defined(PETSC_USE_DEBUG)
5741       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);
5742 #endif
5743       if (im[i] >= rstart && im[i] < rend) {
5744         row      = im[i] - rstart;
5745         lastcol1 = -1;
5746         rp1      = aj + ai[row];
5747         ap1      = aa + ai[row];
5748         rmax1    = aimax[row];
5749         nrow1    = ailen[row];
5750         low1     = 0;
5751         high1    = nrow1;
5752         lastcol2 = -1;
5753         rp2      = bj + bi[row];
5754         ap2      = ba + bi[row];
5755         rmax2    = bimax[row];
5756         nrow2    = bilen[row];
5757         low2     = 0;
5758         high2    = nrow2;
5759 
5760         for (j=0; j<n; j++) {
5761           if (roworiented) value = v[i*n+j];
5762           else value = v[i+j*m];
5763           if (ignorezeroentries && value == 0.0 && (addv == ADD_VALUES)) continue;
5764           if (in[j] >= cstart && in[j] < cend) {
5765             col = in[j] - cstart;
5766             MatSetValues_SeqAIJ_A_Private(row,col,value,addv);
5767           } else if (in[j] < 0) continue;
5768 #if defined(PETSC_USE_DEBUG)
5769           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);
5770 #endif
5771           else {
5772             if (mat->was_assembled) {
5773               if (!aij->colmap) {
5774                 ierr = MatCreateColmap_MPIAIJ_Private(mat);CHKERRQ(ierr);
5775               }
5776 #if defined(PETSC_USE_CTABLE)
5777               ierr = PetscTableFind(aij->colmap,in[j]+1,&col);CHKERRQ(ierr);
5778               col--;
5779 #else
5780               col = aij->colmap[in[j]] - 1;
5781 #endif
5782               if (col < 0 && !((Mat_SeqAIJ*)(aij->A->data))->nonew) {
5783                 ierr = MatDisAssemble_MPIAIJ(mat);CHKERRQ(ierr);
5784                 col  =  in[j];
5785                 /* Reinitialize the variables required by MatSetValues_SeqAIJ_B_Private() */
5786                 B     = aij->B;
5787                 b     = (Mat_SeqAIJ*)B->data;
5788                 bimax = b->imax; bi = b->i; bilen = b->ilen; bj = b->j;
5789                 rp2   = bj + bi[row];
5790                 ap2   = ba + bi[row];
5791                 rmax2 = bimax[row];
5792                 nrow2 = bilen[row];
5793                 low2  = 0;
5794                 high2 = nrow2;
5795                 bm    = aij->B->rmap->n;
5796                 ba    = b->a;
5797               }
5798             } else col = in[j];
5799             MatSetValues_SeqAIJ_B_Private(row,col,value,addv);
5800           }
5801         }
5802       } else if (!aij->donotstash) {
5803         if (roworiented) {
5804           ierr = MatStashValuesRow_Private(&mat->stash,im[i],n,in,v+i*n,(PetscBool)(ignorezeroentries && (addv == ADD_VALUES)));CHKERRQ(ierr);
5805         } else {
5806           ierr = MatStashValuesCol_Private(&mat->stash,im[i],n,in,v+i,m,(PetscBool)(ignorezeroentries && (addv == ADD_VALUES)));CHKERRQ(ierr);
5807         }
5808       }
5809     }
5810   }
5811   PetscFunctionReturnVoid();
5812 }
5813 
5814