xref: /petsc/src/mat/impls/aij/mpi/mpiaij.c (revision b1b1104fb3564ca1342e845fa7119e30388145b7)
1 
2 #include <../src/mat/impls/aij/mpi/mpiaij.h>   /*I "petscmat.h" I*/
3 #include <petsc-private/vecimpl.h>
4 #include <petsc-private/isimpl.h>
5 #include <petscblaslapack.h>
6 #include <petscsf.h>
7 
8 /*MC
9    MATAIJ - MATAIJ = "aij" - A matrix type to be used for sparse matrices.
10 
11    This matrix type is identical to MATSEQAIJ when constructed with a single process communicator,
12    and MATMPIAIJ otherwise.  As a result, for single process communicators,
13   MatSeqAIJSetPreallocation is supported, and similarly MatMPIAIJSetPreallocation is supported
14   for communicators controlling multiple processes.  It is recommended that you call both of
15   the above preallocation routines for simplicity.
16 
17    Options Database Keys:
18 . -mat_type aij - sets the matrix type to "aij" during a call to MatSetFromOptions()
19 
20   Developer Notes: Subclasses include MATAIJCUSP, MATAIJCUSPARSE, MATAIJPERM, MATAIJCRL, and also automatically switches over to use inodes when
21    enough exist.
22 
23   Level: beginner
24 
25 .seealso: MatCreateAIJ(), MatCreateSeqAIJ(), MATSEQAIJ,MATMPIAIJ
26 M*/
27 
28 /*MC
29    MATAIJCRL - MATAIJCRL = "aijcrl" - A matrix type to be used for sparse matrices.
30 
31    This matrix type is identical to MATSEQAIJCRL when constructed with a single process communicator,
32    and MATMPIAIJCRL otherwise.  As a result, for single process communicators,
33    MatSeqAIJSetPreallocation() is supported, and similarly MatMPIAIJSetPreallocation() is supported
34   for communicators controlling multiple processes.  It is recommended that you call both of
35   the above preallocation routines for simplicity.
36 
37    Options Database Keys:
38 . -mat_type aijcrl - sets the matrix type to "aijcrl" during a call to MatSetFromOptions()
39 
40   Level: beginner
41 
42 .seealso: MatCreateMPIAIJCRL,MATSEQAIJCRL,MATMPIAIJCRL, MATSEQAIJCRL, MATMPIAIJCRL
43 M*/
44 
45 #undef __FUNCT__
46 #define __FUNCT__ "MatFindNonzeroRows_MPIAIJ"
47 PetscErrorCode MatFindNonzeroRows_MPIAIJ(Mat M,IS *keptrows)
48 {
49   PetscErrorCode  ierr;
50   Mat_MPIAIJ      *mat = (Mat_MPIAIJ*)M->data;
51   Mat_SeqAIJ      *a   = (Mat_SeqAIJ*)mat->A->data;
52   Mat_SeqAIJ      *b   = (Mat_SeqAIJ*)mat->B->data;
53   const PetscInt  *ia,*ib;
54   const MatScalar *aa,*bb;
55   PetscInt        na,nb,i,j,*rows,cnt=0,n0rows;
56   PetscInt        m = M->rmap->n,rstart = M->rmap->rstart;
57 
58   PetscFunctionBegin;
59   *keptrows = 0;
60   ia        = a->i;
61   ib        = b->i;
62   for (i=0; i<m; i++) {
63     na = ia[i+1] - ia[i];
64     nb = ib[i+1] - ib[i];
65     if (!na && !nb) {
66       cnt++;
67       goto ok1;
68     }
69     aa = a->a + ia[i];
70     for (j=0; j<na; j++) {
71       if (aa[j] != 0.0) goto ok1;
72     }
73     bb = b->a + ib[i];
74     for (j=0; j <nb; j++) {
75       if (bb[j] != 0.0) goto ok1;
76     }
77     cnt++;
78 ok1:;
79   }
80   ierr = MPI_Allreduce(&cnt,&n0rows,1,MPIU_INT,MPIU_SUM,PetscObjectComm((PetscObject)M));CHKERRQ(ierr);
81   if (!n0rows) PetscFunctionReturn(0);
82   ierr = PetscMalloc1(M->rmap->n-cnt,&rows);CHKERRQ(ierr);
83   cnt  = 0;
84   for (i=0; i<m; i++) {
85     na = ia[i+1] - ia[i];
86     nb = ib[i+1] - ib[i];
87     if (!na && !nb) continue;
88     aa = a->a + ia[i];
89     for (j=0; j<na;j++) {
90       if (aa[j] != 0.0) {
91         rows[cnt++] = rstart + i;
92         goto ok2;
93       }
94     }
95     bb = b->a + ib[i];
96     for (j=0; j<nb; j++) {
97       if (bb[j] != 0.0) {
98         rows[cnt++] = rstart + i;
99         goto ok2;
100       }
101     }
102 ok2:;
103   }
104   ierr = ISCreateGeneral(PetscObjectComm((PetscObject)M),cnt,rows,PETSC_OWN_POINTER,keptrows);CHKERRQ(ierr);
105   PetscFunctionReturn(0);
106 }
107 
108 #undef __FUNCT__
109 #define __FUNCT__ "MatDiagonalSet_MPIAIJ"
110 PetscErrorCode  MatDiagonalSet_MPIAIJ(Mat Y,Vec D,InsertMode is)
111 {
112   PetscErrorCode    ierr;
113   Mat_MPIAIJ        *aij = (Mat_MPIAIJ*) Y->data;
114 
115   PetscFunctionBegin;
116   if (Y->assembled && Y->rmap->rstart == Y->cmap->rstart && Y->rmap->rend == Y->cmap->rend) {
117     ierr = MatDiagonalSet(aij->A,D,is);CHKERRQ(ierr);
118   } else {
119     ierr = MatDiagonalSet_Default(Y,D,is);CHKERRQ(ierr);
120   }
121   PetscFunctionReturn(0);
122 }
123 
124 
125 #undef __FUNCT__
126 #define __FUNCT__ "MatFindZeroDiagonals_MPIAIJ"
127 PetscErrorCode MatFindZeroDiagonals_MPIAIJ(Mat M,IS *zrows)
128 {
129   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)M->data;
130   PetscErrorCode ierr;
131   PetscInt       i,rstart,nrows,*rows;
132 
133   PetscFunctionBegin;
134   *zrows = NULL;
135   ierr   = MatFindZeroDiagonals_SeqAIJ_Private(aij->A,&nrows,&rows);CHKERRQ(ierr);
136   ierr   = MatGetOwnershipRange(M,&rstart,NULL);CHKERRQ(ierr);
137   for (i=0; i<nrows; i++) rows[i] += rstart;
138   ierr = ISCreateGeneral(PetscObjectComm((PetscObject)M),nrows,rows,PETSC_OWN_POINTER,zrows);CHKERRQ(ierr);
139   PetscFunctionReturn(0);
140 }
141 
142 #undef __FUNCT__
143 #define __FUNCT__ "MatGetColumnNorms_MPIAIJ"
144 PetscErrorCode MatGetColumnNorms_MPIAIJ(Mat A,NormType type,PetscReal *norms)
145 {
146   PetscErrorCode ierr;
147   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)A->data;
148   PetscInt       i,n,*garray = aij->garray;
149   Mat_SeqAIJ     *a_aij = (Mat_SeqAIJ*) aij->A->data;
150   Mat_SeqAIJ     *b_aij = (Mat_SeqAIJ*) aij->B->data;
151   PetscReal      *work;
152 
153   PetscFunctionBegin;
154   ierr = MatGetSize(A,NULL,&n);CHKERRQ(ierr);
155   ierr = PetscCalloc1(n,&work);CHKERRQ(ierr);
156   if (type == NORM_2) {
157     for (i=0; i<a_aij->i[aij->A->rmap->n]; i++) {
158       work[A->cmap->rstart + a_aij->j[i]] += PetscAbsScalar(a_aij->a[i]*a_aij->a[i]);
159     }
160     for (i=0; i<b_aij->i[aij->B->rmap->n]; i++) {
161       work[garray[b_aij->j[i]]] += PetscAbsScalar(b_aij->a[i]*b_aij->a[i]);
162     }
163   } else if (type == NORM_1) {
164     for (i=0; i<a_aij->i[aij->A->rmap->n]; i++) {
165       work[A->cmap->rstart + a_aij->j[i]] += PetscAbsScalar(a_aij->a[i]);
166     }
167     for (i=0; i<b_aij->i[aij->B->rmap->n]; i++) {
168       work[garray[b_aij->j[i]]] += PetscAbsScalar(b_aij->a[i]);
169     }
170   } else if (type == NORM_INFINITY) {
171     for (i=0; i<a_aij->i[aij->A->rmap->n]; i++) {
172       work[A->cmap->rstart + a_aij->j[i]] = PetscMax(PetscAbsScalar(a_aij->a[i]), work[A->cmap->rstart + a_aij->j[i]]);
173     }
174     for (i=0; i<b_aij->i[aij->B->rmap->n]; i++) {
175       work[garray[b_aij->j[i]]] = PetscMax(PetscAbsScalar(b_aij->a[i]),work[garray[b_aij->j[i]]]);
176     }
177 
178   } else SETERRQ(PetscObjectComm((PetscObject)A),PETSC_ERR_ARG_WRONG,"Unknown NormType");
179   if (type == NORM_INFINITY) {
180     ierr = MPI_Allreduce(work,norms,n,MPIU_REAL,MPIU_MAX,PetscObjectComm((PetscObject)A));CHKERRQ(ierr);
181   } else {
182     ierr = MPI_Allreduce(work,norms,n,MPIU_REAL,MPIU_SUM,PetscObjectComm((PetscObject)A));CHKERRQ(ierr);
183   }
184   ierr = PetscFree(work);CHKERRQ(ierr);
185   if (type == NORM_2) {
186     for (i=0; i<n; i++) norms[i] = PetscSqrtReal(norms[i]);
187   }
188   PetscFunctionReturn(0);
189 }
190 
191 #undef __FUNCT__
192 #define __FUNCT__ "MatFindOffBlockDiagonalEntries_MPIAIJ"
193 PetscErrorCode MatFindOffBlockDiagonalEntries_MPIAIJ(Mat A,IS *is)
194 {
195   Mat_MPIAIJ      *a  = (Mat_MPIAIJ*)A->data;
196   IS              sis,gis;
197   PetscErrorCode  ierr;
198   const PetscInt  *isis,*igis;
199   PetscInt        n,*iis,nsis,ngis,rstart,i;
200 
201   PetscFunctionBegin;
202   ierr = MatFindOffBlockDiagonalEntries(a->A,&sis);CHKERRQ(ierr);
203   ierr = MatFindNonzeroRows(a->B,&gis);CHKERRQ(ierr);
204   ierr = ISGetSize(gis,&ngis);CHKERRQ(ierr);
205   ierr = ISGetSize(sis,&nsis);CHKERRQ(ierr);
206   ierr = ISGetIndices(sis,&isis);CHKERRQ(ierr);
207   ierr = ISGetIndices(gis,&igis);CHKERRQ(ierr);
208 
209   ierr = PetscMalloc1(ngis+nsis,&iis);CHKERRQ(ierr);
210   ierr = PetscMemcpy(iis,igis,ngis*sizeof(PetscInt));CHKERRQ(ierr);
211   ierr = PetscMemcpy(iis+ngis,isis,nsis*sizeof(PetscInt));CHKERRQ(ierr);
212   n    = ngis + nsis;
213   ierr = PetscSortRemoveDupsInt(&n,iis);CHKERRQ(ierr);
214   ierr = MatGetOwnershipRange(A,&rstart,NULL);CHKERRQ(ierr);
215   for (i=0; i<n; i++) iis[i] += rstart;
216   ierr = ISCreateGeneral(PetscObjectComm((PetscObject)A),n,iis,PETSC_OWN_POINTER,is);CHKERRQ(ierr);
217 
218   ierr = ISRestoreIndices(sis,&isis);CHKERRQ(ierr);
219   ierr = ISRestoreIndices(gis,&igis);CHKERRQ(ierr);
220   ierr = ISDestroy(&sis);CHKERRQ(ierr);
221   ierr = ISDestroy(&gis);CHKERRQ(ierr);
222   PetscFunctionReturn(0);
223 }
224 
225 #undef __FUNCT__
226 #define __FUNCT__ "MatDistribute_MPIAIJ"
227 /*
228     Distributes a SeqAIJ matrix across a set of processes. Code stolen from
229     MatLoad_MPIAIJ(). Horrible lack of reuse. Should be a routine for each matrix type.
230 
231     Only for square matrices
232 
233     Used by a preconditioner, hence PETSC_EXTERN
234 */
235 PETSC_EXTERN PetscErrorCode MatDistribute_MPIAIJ(MPI_Comm comm,Mat gmat,PetscInt m,MatReuse reuse,Mat *inmat)
236 {
237   PetscMPIInt    rank,size;
238   PetscInt       *rowners,*dlens,*olens,i,rstart,rend,j,jj,nz = 0,*gmataj,cnt,row,*ld,bses[2];
239   PetscErrorCode ierr;
240   Mat            mat;
241   Mat_SeqAIJ     *gmata;
242   PetscMPIInt    tag;
243   MPI_Status     status;
244   PetscBool      aij;
245   MatScalar      *gmataa,*ao,*ad,*gmataarestore=0;
246 
247   PetscFunctionBegin;
248   ierr = MPI_Comm_rank(comm,&rank);CHKERRQ(ierr);
249   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
250   if (!rank) {
251     ierr = PetscObjectTypeCompare((PetscObject)gmat,MATSEQAIJ,&aij);CHKERRQ(ierr);
252     if (!aij) SETERRQ1(PetscObjectComm((PetscObject)gmat),PETSC_ERR_SUP,"Currently no support for input matrix of type %s\n",((PetscObject)gmat)->type_name);
253   }
254   if (reuse == MAT_INITIAL_MATRIX) {
255     ierr = MatCreate(comm,&mat);CHKERRQ(ierr);
256     ierr = MatSetSizes(mat,m,m,PETSC_DETERMINE,PETSC_DETERMINE);CHKERRQ(ierr);
257     ierr = MatGetBlockSizes(gmat,&bses[0],&bses[1]);CHKERRQ(ierr);
258     ierr = MPI_Bcast(bses,2,MPIU_INT,0,comm);CHKERRQ(ierr);
259     ierr = MatSetBlockSizes(mat,bses[0],bses[1]);CHKERRQ(ierr);
260     ierr = MatSetType(mat,MATAIJ);CHKERRQ(ierr);
261     ierr = PetscMalloc1(size+1,&rowners);CHKERRQ(ierr);
262     ierr = PetscMalloc2(m,&dlens,m,&olens);CHKERRQ(ierr);
263     ierr = MPI_Allgather(&m,1,MPIU_INT,rowners+1,1,MPIU_INT,comm);CHKERRQ(ierr);
264 
265     rowners[0] = 0;
266     for (i=2; i<=size; i++) rowners[i] += rowners[i-1];
267     rstart = rowners[rank];
268     rend   = rowners[rank+1];
269     ierr   = PetscObjectGetNewTag((PetscObject)mat,&tag);CHKERRQ(ierr);
270     if (!rank) {
271       gmata = (Mat_SeqAIJ*) gmat->data;
272       /* send row lengths to all processors */
273       for (i=0; i<m; i++) dlens[i] = gmata->ilen[i];
274       for (i=1; i<size; i++) {
275         ierr = MPI_Send(gmata->ilen + rowners[i],rowners[i+1]-rowners[i],MPIU_INT,i,tag,comm);CHKERRQ(ierr);
276       }
277       /* determine number diagonal and off-diagonal counts */
278       ierr = PetscMemzero(olens,m*sizeof(PetscInt));CHKERRQ(ierr);
279       ierr = PetscCalloc1(m,&ld);CHKERRQ(ierr);
280       jj   = 0;
281       for (i=0; i<m; i++) {
282         for (j=0; j<dlens[i]; j++) {
283           if (gmata->j[jj] < rstart) ld[i]++;
284           if (gmata->j[jj] < rstart || gmata->j[jj] >= rend) olens[i]++;
285           jj++;
286         }
287       }
288       /* send column indices to other processes */
289       for (i=1; i<size; i++) {
290         nz   = gmata->i[rowners[i+1]]-gmata->i[rowners[i]];
291         ierr = MPI_Send(&nz,1,MPIU_INT,i,tag,comm);CHKERRQ(ierr);
292         ierr = MPI_Send(gmata->j + gmata->i[rowners[i]],nz,MPIU_INT,i,tag,comm);CHKERRQ(ierr);
293       }
294 
295       /* send numerical values to other processes */
296       for (i=1; i<size; i++) {
297         nz   = gmata->i[rowners[i+1]]-gmata->i[rowners[i]];
298         ierr = MPI_Send(gmata->a + gmata->i[rowners[i]],nz,MPIU_SCALAR,i,tag,comm);CHKERRQ(ierr);
299       }
300       gmataa = gmata->a;
301       gmataj = gmata->j;
302 
303     } else {
304       /* receive row lengths */
305       ierr = MPI_Recv(dlens,m,MPIU_INT,0,tag,comm,&status);CHKERRQ(ierr);
306       /* receive column indices */
307       ierr = MPI_Recv(&nz,1,MPIU_INT,0,tag,comm,&status);CHKERRQ(ierr);
308       ierr = PetscMalloc2(nz,&gmataa,nz,&gmataj);CHKERRQ(ierr);
309       ierr = MPI_Recv(gmataj,nz,MPIU_INT,0,tag,comm,&status);CHKERRQ(ierr);
310       /* determine number diagonal and off-diagonal counts */
311       ierr = PetscMemzero(olens,m*sizeof(PetscInt));CHKERRQ(ierr);
312       ierr = PetscCalloc1(m,&ld);CHKERRQ(ierr);
313       jj   = 0;
314       for (i=0; i<m; i++) {
315         for (j=0; j<dlens[i]; j++) {
316           if (gmataj[jj] < rstart) ld[i]++;
317           if (gmataj[jj] < rstart || gmataj[jj] >= rend) olens[i]++;
318           jj++;
319         }
320       }
321       /* receive numerical values */
322       ierr = PetscMemzero(gmataa,nz*sizeof(PetscScalar));CHKERRQ(ierr);
323       ierr = MPI_Recv(gmataa,nz,MPIU_SCALAR,0,tag,comm,&status);CHKERRQ(ierr);
324     }
325     /* set preallocation */
326     for (i=0; i<m; i++) {
327       dlens[i] -= olens[i];
328     }
329     ierr = MatSeqAIJSetPreallocation(mat,0,dlens);CHKERRQ(ierr);
330     ierr = MatMPIAIJSetPreallocation(mat,0,dlens,0,olens);CHKERRQ(ierr);
331 
332     for (i=0; i<m; i++) {
333       dlens[i] += olens[i];
334     }
335     cnt = 0;
336     for (i=0; i<m; i++) {
337       row  = rstart + i;
338       ierr = MatSetValues(mat,1,&row,dlens[i],gmataj+cnt,gmataa+cnt,INSERT_VALUES);CHKERRQ(ierr);
339       cnt += dlens[i];
340     }
341     if (rank) {
342       ierr = PetscFree2(gmataa,gmataj);CHKERRQ(ierr);
343     }
344     ierr = PetscFree2(dlens,olens);CHKERRQ(ierr);
345     ierr = PetscFree(rowners);CHKERRQ(ierr);
346 
347     ((Mat_MPIAIJ*)(mat->data))->ld = ld;
348 
349     *inmat = mat;
350   } else {   /* column indices are already set; only need to move over numerical values from process 0 */
351     Mat_SeqAIJ *Ad = (Mat_SeqAIJ*)((Mat_MPIAIJ*)((*inmat)->data))->A->data;
352     Mat_SeqAIJ *Ao = (Mat_SeqAIJ*)((Mat_MPIAIJ*)((*inmat)->data))->B->data;
353     mat  = *inmat;
354     ierr = PetscObjectGetNewTag((PetscObject)mat,&tag);CHKERRQ(ierr);
355     if (!rank) {
356       /* send numerical values to other processes */
357       gmata  = (Mat_SeqAIJ*) gmat->data;
358       ierr   = MatGetOwnershipRanges(mat,(const PetscInt**)&rowners);CHKERRQ(ierr);
359       gmataa = gmata->a;
360       for (i=1; i<size; i++) {
361         nz   = gmata->i[rowners[i+1]]-gmata->i[rowners[i]];
362         ierr = MPI_Send(gmataa + gmata->i[rowners[i]],nz,MPIU_SCALAR,i,tag,comm);CHKERRQ(ierr);
363       }
364       nz = gmata->i[rowners[1]]-gmata->i[rowners[0]];
365     } else {
366       /* receive numerical values from process 0*/
367       nz   = Ad->nz + Ao->nz;
368       ierr = PetscMalloc1(nz,&gmataa);CHKERRQ(ierr); gmataarestore = gmataa;
369       ierr = MPI_Recv(gmataa,nz,MPIU_SCALAR,0,tag,comm,&status);CHKERRQ(ierr);
370     }
371     /* transfer numerical values into the diagonal A and off diagonal B parts of mat */
372     ld = ((Mat_MPIAIJ*)(mat->data))->ld;
373     ad = Ad->a;
374     ao = Ao->a;
375     if (mat->rmap->n) {
376       i  = 0;
377       nz = ld[i];                                   ierr = PetscMemcpy(ao,gmataa,nz*sizeof(PetscScalar));CHKERRQ(ierr); ao += nz; gmataa += nz;
378       nz = Ad->i[i+1] - Ad->i[i];                   ierr = PetscMemcpy(ad,gmataa,nz*sizeof(PetscScalar));CHKERRQ(ierr); ad += nz; gmataa += nz;
379     }
380     for (i=1; i<mat->rmap->n; i++) {
381       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;
382       nz = Ad->i[i+1] - Ad->i[i];                   ierr = PetscMemcpy(ad,gmataa,nz*sizeof(PetscScalar));CHKERRQ(ierr); ad += nz; gmataa += nz;
383     }
384     i--;
385     if (mat->rmap->n) {
386       nz = Ao->i[i+1] - Ao->i[i] - ld[i];           ierr = PetscMemcpy(ao,gmataa,nz*sizeof(PetscScalar));CHKERRQ(ierr);
387     }
388     if (rank) {
389       ierr = PetscFree(gmataarestore);CHKERRQ(ierr);
390     }
391   }
392   ierr = MatAssemblyBegin(mat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
393   ierr = MatAssemblyEnd(mat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
394   PetscFunctionReturn(0);
395 }
396 
397 /*
398   Local utility routine that creates a mapping from the global column
399 number to the local number in the off-diagonal part of the local
400 storage of the matrix.  When PETSC_USE_CTABLE is used this is scalable at
401 a slightly higher hash table cost; without it it is not scalable (each processor
402 has an order N integer array but is fast to acess.
403 */
404 #undef __FUNCT__
405 #define __FUNCT__ "MatCreateColmap_MPIAIJ_Private"
406 PetscErrorCode MatCreateColmap_MPIAIJ_Private(Mat mat)
407 {
408   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
409   PetscErrorCode ierr;
410   PetscInt       n = aij->B->cmap->n,i;
411 
412   PetscFunctionBegin;
413   if (!aij->garray) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_PLIB,"MPIAIJ Matrix was assembled but is missing garray");
414 #if defined(PETSC_USE_CTABLE)
415   ierr = PetscTableCreate(n,mat->cmap->N+1,&aij->colmap);CHKERRQ(ierr);
416   for (i=0; i<n; i++) {
417     ierr = PetscTableAdd(aij->colmap,aij->garray[i]+1,i+1,INSERT_VALUES);CHKERRQ(ierr);
418   }
419 #else
420   ierr = PetscCalloc1(mat->cmap->N+1,&aij->colmap);CHKERRQ(ierr);
421   ierr = PetscLogObjectMemory((PetscObject)mat,(mat->cmap->N+1)*sizeof(PetscInt));CHKERRQ(ierr);
422   for (i=0; i<n; i++) aij->colmap[aij->garray[i]] = i+1;
423 #endif
424   PetscFunctionReturn(0);
425 }
426 
427 #define MatSetValues_SeqAIJ_A_Private(row,col,value,addv,orow,ocol)     \
428 { \
429     if (col <= lastcol1)  low1 = 0;     \
430     else                 high1 = nrow1; \
431     lastcol1 = col;\
432     while (high1-low1 > 5) { \
433       t = (low1+high1)/2; \
434       if (rp1[t] > col) high1 = t; \
435       else              low1  = t; \
436     } \
437       for (_i=low1; _i<high1; _i++) { \
438         if (rp1[_i] > col) break; \
439         if (rp1[_i] == col) { \
440           if (addv == ADD_VALUES) ap1[_i] += value;   \
441           else                    ap1[_i] = value; \
442           goto a_noinsert; \
443         } \
444       }  \
445       if (value == 0.0 && ignorezeroentries) {low1 = 0; high1 = nrow1;goto a_noinsert;} \
446       if (nonew == 1) {low1 = 0; high1 = nrow1; goto a_noinsert;}                \
447       if (nonew == -1) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Inserting a new nonzero at global row/column (%D, %D) into matrix", orow, ocol); \
448       MatSeqXAIJReallocateAIJ(A,am,1,nrow1,row,col,rmax1,aa,ai,aj,rp1,ap1,aimax,nonew,MatScalar); \
449       N = nrow1++ - 1; a->nz++; high1++; \
450       /* shift up all the later entries in this row */ \
451       for (ii=N; ii>=_i; ii--) { \
452         rp1[ii+1] = rp1[ii]; \
453         ap1[ii+1] = ap1[ii]; \
454       } \
455       rp1[_i] = col;  \
456       ap1[_i] = value;  \
457       A->nonzerostate++;\
458       a_noinsert: ; \
459       ailen[row] = nrow1; \
460 }
461 
462 
463 #define MatSetValues_SeqAIJ_B_Private(row,col,value,addv,orow,ocol) \
464   { \
465     if (col <= lastcol2) low2 = 0;                        \
466     else high2 = nrow2;                                   \
467     lastcol2 = col;                                       \
468     while (high2-low2 > 5) {                              \
469       t = (low2+high2)/2;                                 \
470       if (rp2[t] > col) high2 = t;                        \
471       else             low2  = t;                         \
472     }                                                     \
473     for (_i=low2; _i<high2; _i++) {                       \
474       if (rp2[_i] > col) break;                           \
475       if (rp2[_i] == col) {                               \
476         if (addv == ADD_VALUES) ap2[_i] += value;         \
477         else                    ap2[_i] = value;          \
478         goto b_noinsert;                                  \
479       }                                                   \
480     }                                                     \
481     if (value == 0.0 && ignorezeroentries) {low2 = 0; high2 = nrow2; goto b_noinsert;} \
482     if (nonew == 1) {low2 = 0; high2 = nrow2; goto b_noinsert;}                        \
483     if (nonew == -1) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Inserting a new nonzero at global row/column (%D, %D) into matrix", orow, ocol); \
484     MatSeqXAIJReallocateAIJ(B,bm,1,nrow2,row,col,rmax2,ba,bi,bj,rp2,ap2,bimax,nonew,MatScalar); \
485     N = nrow2++ - 1; b->nz++; high2++;                    \
486     /* shift up all the later entries in this row */      \
487     for (ii=N; ii>=_i; ii--) {                            \
488       rp2[ii+1] = rp2[ii];                                \
489       ap2[ii+1] = ap2[ii];                                \
490     }                                                     \
491     rp2[_i] = col;                                        \
492     ap2[_i] = value;                                      \
493     B->nonzerostate++;                                    \
494     b_noinsert: ;                                         \
495     bilen[row] = nrow2;                                   \
496   }
497 
498 #undef __FUNCT__
499 #define __FUNCT__ "MatSetValuesRow_MPIAIJ"
500 PetscErrorCode MatSetValuesRow_MPIAIJ(Mat A,PetscInt row,const PetscScalar v[])
501 {
502   Mat_MPIAIJ     *mat = (Mat_MPIAIJ*)A->data;
503   Mat_SeqAIJ     *a   = (Mat_SeqAIJ*)mat->A->data,*b = (Mat_SeqAIJ*)mat->B->data;
504   PetscErrorCode ierr;
505   PetscInt       l,*garray = mat->garray,diag;
506 
507   PetscFunctionBegin;
508   /* code only works for square matrices A */
509 
510   /* find size of row to the left of the diagonal part */
511   ierr = MatGetOwnershipRange(A,&diag,0);CHKERRQ(ierr);
512   row  = row - diag;
513   for (l=0; l<b->i[row+1]-b->i[row]; l++) {
514     if (garray[b->j[b->i[row]+l]] > diag) break;
515   }
516   ierr = PetscMemcpy(b->a+b->i[row],v,l*sizeof(PetscScalar));CHKERRQ(ierr);
517 
518   /* diagonal part */
519   ierr = PetscMemcpy(a->a+a->i[row],v+l,(a->i[row+1]-a->i[row])*sizeof(PetscScalar));CHKERRQ(ierr);
520 
521   /* right of diagonal part */
522   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);
523   PetscFunctionReturn(0);
524 }
525 
526 #undef __FUNCT__
527 #define __FUNCT__ "MatSetValues_MPIAIJ"
528 PetscErrorCode MatSetValues_MPIAIJ(Mat mat,PetscInt m,const PetscInt im[],PetscInt n,const PetscInt in[],const PetscScalar v[],InsertMode addv)
529 {
530   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
531   PetscScalar    value;
532   PetscErrorCode ierr;
533   PetscInt       i,j,rstart  = mat->rmap->rstart,rend = mat->rmap->rend;
534   PetscInt       cstart      = mat->cmap->rstart,cend = mat->cmap->rend,row,col;
535   PetscBool      roworiented = aij->roworiented;
536 
537   /* Some Variables required in the macro */
538   Mat        A                 = aij->A;
539   Mat_SeqAIJ *a                = (Mat_SeqAIJ*)A->data;
540   PetscInt   *aimax            = a->imax,*ai = a->i,*ailen = a->ilen,*aj = a->j;
541   MatScalar  *aa               = a->a;
542   PetscBool  ignorezeroentries = a->ignorezeroentries;
543   Mat        B                 = aij->B;
544   Mat_SeqAIJ *b                = (Mat_SeqAIJ*)B->data;
545   PetscInt   *bimax            = b->imax,*bi = b->i,*bilen = b->ilen,*bj = b->j,bm = aij->B->rmap->n,am = aij->A->rmap->n;
546   MatScalar  *ba               = b->a;
547 
548   PetscInt  *rp1,*rp2,ii,nrow1,nrow2,_i,rmax1,rmax2,N,low1,high1,low2,high2,t,lastcol1,lastcol2;
549   PetscInt  nonew;
550   MatScalar *ap1,*ap2;
551 
552   PetscFunctionBegin;
553   for (i=0; i<m; i++) {
554     if (im[i] < 0) continue;
555 #if defined(PETSC_USE_DEBUG)
556     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);
557 #endif
558     if (im[i] >= rstart && im[i] < rend) {
559       row      = im[i] - rstart;
560       lastcol1 = -1;
561       rp1      = aj + ai[row];
562       ap1      = aa + ai[row];
563       rmax1    = aimax[row];
564       nrow1    = ailen[row];
565       low1     = 0;
566       high1    = nrow1;
567       lastcol2 = -1;
568       rp2      = bj + bi[row];
569       ap2      = ba + bi[row];
570       rmax2    = bimax[row];
571       nrow2    = bilen[row];
572       low2     = 0;
573       high2    = nrow2;
574 
575       for (j=0; j<n; j++) {
576         if (roworiented) value = v[i*n+j];
577         else             value = v[i+j*m];
578         if (ignorezeroentries && value == 0.0 && (addv == ADD_VALUES)) continue;
579         if (in[j] >= cstart && in[j] < cend) {
580           col   = in[j] - cstart;
581           nonew = a->nonew;
582           MatSetValues_SeqAIJ_A_Private(row,col,value,addv,im[i],in[j]);
583         } else if (in[j] < 0) continue;
584 #if defined(PETSC_USE_DEBUG)
585         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);
586 #endif
587         else {
588           if (mat->was_assembled) {
589             if (!aij->colmap) {
590               ierr = MatCreateColmap_MPIAIJ_Private(mat);CHKERRQ(ierr);
591             }
592 #if defined(PETSC_USE_CTABLE)
593             ierr = PetscTableFind(aij->colmap,in[j]+1,&col);CHKERRQ(ierr);
594             col--;
595 #else
596             col = aij->colmap[in[j]] - 1;
597 #endif
598             if (col < 0 && !((Mat_SeqAIJ*)(aij->B->data))->nonew) {
599               ierr = MatDisAssemble_MPIAIJ(mat);CHKERRQ(ierr);
600               col  =  in[j];
601               /* Reinitialize the variables required by MatSetValues_SeqAIJ_B_Private() */
602               B     = aij->B;
603               b     = (Mat_SeqAIJ*)B->data;
604               bimax = b->imax; bi = b->i; bilen = b->ilen; bj = b->j; ba = b->a;
605               rp2   = bj + bi[row];
606               ap2   = ba + bi[row];
607               rmax2 = bimax[row];
608               nrow2 = bilen[row];
609               low2  = 0;
610               high2 = nrow2;
611               bm    = aij->B->rmap->n;
612               ba    = b->a;
613             } else if (col < 0) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Inserting a new nonzero at global row/column (%D, %D) into matrix", im[i], in[j]);
614           } else col = in[j];
615           nonew = b->nonew;
616           MatSetValues_SeqAIJ_B_Private(row,col,value,addv,im[i],in[j]);
617         }
618       }
619     } else {
620       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]);
621       if (!aij->donotstash) {
622         mat->assembled = PETSC_FALSE;
623         if (roworiented) {
624           ierr = MatStashValuesRow_Private(&mat->stash,im[i],n,in,v+i*n,(PetscBool)(ignorezeroentries && (addv == ADD_VALUES)));CHKERRQ(ierr);
625         } else {
626           ierr = MatStashValuesCol_Private(&mat->stash,im[i],n,in,v+i,m,(PetscBool)(ignorezeroentries && (addv == ADD_VALUES)));CHKERRQ(ierr);
627         }
628       }
629     }
630   }
631   PetscFunctionReturn(0);
632 }
633 
634 #undef __FUNCT__
635 #define __FUNCT__ "MatGetValues_MPIAIJ"
636 PetscErrorCode MatGetValues_MPIAIJ(Mat mat,PetscInt m,const PetscInt idxm[],PetscInt n,const PetscInt idxn[],PetscScalar v[])
637 {
638   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
639   PetscErrorCode ierr;
640   PetscInt       i,j,rstart = mat->rmap->rstart,rend = mat->rmap->rend;
641   PetscInt       cstart = mat->cmap->rstart,cend = mat->cmap->rend,row,col;
642 
643   PetscFunctionBegin;
644   for (i=0; i<m; i++) {
645     if (idxm[i] < 0) continue; /* SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Negative row: %D",idxm[i]);*/
646     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);
647     if (idxm[i] >= rstart && idxm[i] < rend) {
648       row = idxm[i] - rstart;
649       for (j=0; j<n; j++) {
650         if (idxn[j] < 0) continue; /* SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Negative column: %D",idxn[j]); */
651         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);
652         if (idxn[j] >= cstart && idxn[j] < cend) {
653           col  = idxn[j] - cstart;
654           ierr = MatGetValues(aij->A,1,&row,1,&col,v+i*n+j);CHKERRQ(ierr);
655         } else {
656           if (!aij->colmap) {
657             ierr = MatCreateColmap_MPIAIJ_Private(mat);CHKERRQ(ierr);
658           }
659 #if defined(PETSC_USE_CTABLE)
660           ierr = PetscTableFind(aij->colmap,idxn[j]+1,&col);CHKERRQ(ierr);
661           col--;
662 #else
663           col = aij->colmap[idxn[j]] - 1;
664 #endif
665           if ((col < 0) || (aij->garray[col] != idxn[j])) *(v+i*n+j) = 0.0;
666           else {
667             ierr = MatGetValues(aij->B,1,&row,1,&col,v+i*n+j);CHKERRQ(ierr);
668           }
669         }
670       }
671     } else SETERRQ(PETSC_COMM_SELF,PETSC_ERR_SUP,"Only local values currently supported");
672   }
673   PetscFunctionReturn(0);
674 }
675 
676 extern PetscErrorCode MatMultDiagonalBlock_MPIAIJ(Mat,Vec,Vec);
677 
678 #undef __FUNCT__
679 #define __FUNCT__ "MatAssemblyBegin_MPIAIJ"
680 PetscErrorCode MatAssemblyBegin_MPIAIJ(Mat mat,MatAssemblyType mode)
681 {
682   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
683   PetscErrorCode ierr;
684   PetscInt       nstash,reallocs;
685   InsertMode     addv;
686 
687   PetscFunctionBegin;
688   if (aij->donotstash || mat->nooffprocentries) PetscFunctionReturn(0);
689 
690   /* make sure all processors are either in INSERTMODE or ADDMODE */
691   ierr = MPI_Allreduce((PetscEnum*)&mat->insertmode,(PetscEnum*)&addv,1,MPIU_ENUM,MPI_BOR,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
692   if (addv == (ADD_VALUES|INSERT_VALUES)) SETERRQ(PetscObjectComm((PetscObject)mat),PETSC_ERR_ARG_WRONGSTATE,"Some processors inserted others added");
693   mat->insertmode = addv; /* in case this processor had no cache */
694 
695   ierr = MatStashScatterBegin_Private(mat,&mat->stash,mat->rmap->range);CHKERRQ(ierr);
696   ierr = MatStashGetInfo_Private(&mat->stash,&nstash,&reallocs);CHKERRQ(ierr);
697   ierr = PetscInfo2(aij->A,"Stash has %D entries, uses %D mallocs.\n",nstash,reallocs);CHKERRQ(ierr);
698   PetscFunctionReturn(0);
699 }
700 
701 #undef __FUNCT__
702 #define __FUNCT__ "MatAssemblyEnd_MPIAIJ"
703 PetscErrorCode MatAssemblyEnd_MPIAIJ(Mat mat,MatAssemblyType mode)
704 {
705   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
706   Mat_SeqAIJ     *a   = (Mat_SeqAIJ*)aij->A->data;
707   PetscErrorCode ierr;
708   PetscMPIInt    n;
709   PetscInt       i,j,rstart,ncols,flg;
710   PetscInt       *row,*col;
711   PetscBool      other_disassembled;
712   PetscScalar    *val;
713   InsertMode     addv = mat->insertmode;
714 
715   /* do not use 'b = (Mat_SeqAIJ*)aij->B->data' as B can be reset in disassembly */
716 
717   PetscFunctionBegin;
718   if (!aij->donotstash && !mat->nooffprocentries) {
719     while (1) {
720       ierr = MatStashScatterGetMesg_Private(&mat->stash,&n,&row,&col,&val,&flg);CHKERRQ(ierr);
721       if (!flg) break;
722 
723       for (i=0; i<n; ) {
724         /* Now identify the consecutive vals belonging to the same row */
725         for (j=i,rstart=row[j]; j<n; j++) {
726           if (row[j] != rstart) break;
727         }
728         if (j < n) ncols = j-i;
729         else       ncols = n-i;
730         /* Now assemble all these values with a single function call */
731         ierr = MatSetValues_MPIAIJ(mat,1,row+i,ncols,col+i,val+i,addv);CHKERRQ(ierr);
732 
733         i = j;
734       }
735     }
736     ierr = MatStashScatterEnd_Private(&mat->stash);CHKERRQ(ierr);
737   }
738   ierr = MatAssemblyBegin(aij->A,mode);CHKERRQ(ierr);
739   ierr = MatAssemblyEnd(aij->A,mode);CHKERRQ(ierr);
740 
741   /* determine if any processor has disassembled, if so we must
742      also disassemble ourselfs, in order that we may reassemble. */
743   /*
744      if nonzero structure of submatrix B cannot change then we know that
745      no processor disassembled thus we can skip this stuff
746   */
747   if (!((Mat_SeqAIJ*)aij->B->data)->nonew) {
748     ierr = MPI_Allreduce(&mat->was_assembled,&other_disassembled,1,MPIU_BOOL,MPI_PROD,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
749     if (mat->was_assembled && !other_disassembled) {
750       ierr = MatDisAssemble_MPIAIJ(mat);CHKERRQ(ierr);
751     }
752   }
753   if (!mat->was_assembled && mode == MAT_FINAL_ASSEMBLY) {
754     ierr = MatSetUpMultiply_MPIAIJ(mat);CHKERRQ(ierr);
755   }
756   ierr = MatSetOption(aij->B,MAT_USE_INODES,PETSC_FALSE);CHKERRQ(ierr);
757   ierr = MatAssemblyBegin(aij->B,mode);CHKERRQ(ierr);
758   ierr = MatAssemblyEnd(aij->B,mode);CHKERRQ(ierr);
759 
760   ierr = PetscFree2(aij->rowvalues,aij->rowindices);CHKERRQ(ierr);
761 
762   aij->rowvalues = 0;
763 
764   ierr = VecDestroy(&aij->diag);CHKERRQ(ierr);
765   if (a->inode.size) mat->ops->multdiagonalblock = MatMultDiagonalBlock_MPIAIJ;
766 
767   /* if no new nonzero locations are allowed in matrix then only set the matrix state the first time through */
768   if ((!mat->was_assembled && mode == MAT_FINAL_ASSEMBLY) || !((Mat_SeqAIJ*)(aij->A->data))->nonew) {
769     PetscObjectState state = aij->A->nonzerostate + aij->B->nonzerostate;
770     ierr = MPI_Allreduce(&state,&mat->nonzerostate,1,MPIU_INT64,MPI_SUM,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
771   }
772   PetscFunctionReturn(0);
773 }
774 
775 #undef __FUNCT__
776 #define __FUNCT__ "MatZeroEntries_MPIAIJ"
777 PetscErrorCode MatZeroEntries_MPIAIJ(Mat A)
778 {
779   Mat_MPIAIJ     *l = (Mat_MPIAIJ*)A->data;
780   PetscErrorCode ierr;
781 
782   PetscFunctionBegin;
783   ierr = MatZeroEntries(l->A);CHKERRQ(ierr);
784   ierr = MatZeroEntries(l->B);CHKERRQ(ierr);
785   PetscFunctionReturn(0);
786 }
787 
788 #undef __FUNCT__
789 #define __FUNCT__ "MatZeroRows_MPIAIJ"
790 PetscErrorCode MatZeroRows_MPIAIJ(Mat A,PetscInt N,const PetscInt rows[],PetscScalar diag,Vec x,Vec b)
791 {
792   Mat_MPIAIJ    *mat    = (Mat_MPIAIJ *) A->data;
793   PetscInt      *owners = A->rmap->range;
794   PetscInt       n      = A->rmap->n;
795   PetscSF        sf;
796   PetscInt      *lrows;
797   PetscSFNode   *rrows;
798   PetscInt       r, p = 0, len = 0;
799   PetscErrorCode ierr;
800 
801   PetscFunctionBegin;
802   /* Create SF where leaves are input rows and roots are owned rows */
803   ierr = PetscMalloc1(n, &lrows);CHKERRQ(ierr);
804   for (r = 0; r < n; ++r) lrows[r] = -1;
805   if (!A->nooffproczerorows) {ierr = PetscMalloc1(N, &rrows);CHKERRQ(ierr);}
806   for (r = 0; r < N; ++r) {
807     const PetscInt idx   = rows[r];
808     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);
809     if (idx < owners[p] || owners[p+1] <= idx) { /* short-circuit the search if the last p owns this row too */
810       ierr = PetscLayoutFindOwner(A->rmap,idx,&p);CHKERRQ(ierr);
811     }
812     if (A->nooffproczerorows) {
813       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);
814       lrows[len++] = idx - owners[p];
815     } else {
816       rrows[r].rank = p;
817       rrows[r].index = rows[r] - owners[p];
818     }
819   }
820   if (!A->nooffproczerorows) {
821     ierr = PetscSFCreate(PetscObjectComm((PetscObject) A), &sf);CHKERRQ(ierr);
822     ierr = PetscSFSetGraph(sf, n, N, NULL, PETSC_OWN_POINTER, rrows, PETSC_OWN_POINTER);CHKERRQ(ierr);
823     /* Collect flags for rows to be zeroed */
824     ierr = PetscSFReduceBegin(sf, MPIU_INT, (PetscInt*)rows, lrows, MPI_LOR);CHKERRQ(ierr);
825     ierr = PetscSFReduceEnd(sf, MPIU_INT, (PetscInt*)rows, lrows, MPI_LOR);CHKERRQ(ierr);
826     ierr = PetscSFDestroy(&sf);CHKERRQ(ierr);
827     /* Compress and put in row numbers */
828     for (r = 0; r < n; ++r) if (lrows[r] >= 0) lrows[len++] = r;
829   }
830   /* fix right hand side if needed */
831   if (x && b) {
832     const PetscScalar *xx;
833     PetscScalar       *bb;
834 
835     ierr = VecGetArrayRead(x, &xx);CHKERRQ(ierr);
836     ierr = VecGetArray(b, &bb);CHKERRQ(ierr);
837     for (r = 0; r < len; ++r) bb[lrows[r]] = diag*xx[lrows[r]];
838     ierr = VecRestoreArrayRead(x, &xx);CHKERRQ(ierr);
839     ierr = VecRestoreArray(b, &bb);CHKERRQ(ierr);
840   }
841   /* Must zero l->B before l->A because the (diag) case below may put values into l->B*/
842   ierr = MatZeroRows(mat->B, len, lrows, 0.0, NULL, NULL);CHKERRQ(ierr);
843   if ((diag != 0.0) && (mat->A->rmap->N == mat->A->cmap->N)) {
844     ierr = MatZeroRows(mat->A, len, lrows, diag, NULL, NULL);CHKERRQ(ierr);
845   } else if (diag != 0.0) {
846     ierr = MatZeroRows(mat->A, len, lrows, 0.0, NULL, NULL);CHKERRQ(ierr);
847     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");
848     for (r = 0; r < len; ++r) {
849       const PetscInt row = lrows[r] + A->rmap->rstart;
850       ierr = MatSetValues(A, 1, &row, 1, &row, &diag, INSERT_VALUES);CHKERRQ(ierr);
851     }
852     ierr = MatAssemblyBegin(A, MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
853     ierr = MatAssemblyEnd(A, MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
854   } else {
855     ierr = MatZeroRows(mat->A, len, lrows, 0.0, NULL, NULL);CHKERRQ(ierr);
856   }
857   ierr = PetscFree(lrows);CHKERRQ(ierr);
858 
859   /* only change matrix nonzero state if pattern was allowed to be changed */
860   if (!((Mat_SeqAIJ*)(mat->A->data))->keepnonzeropattern) {
861     PetscObjectState state = mat->A->nonzerostate + mat->B->nonzerostate;
862     ierr = MPI_Allreduce(&state,&A->nonzerostate,1,MPIU_INT64,MPI_SUM,PetscObjectComm((PetscObject)A));CHKERRQ(ierr);
863   }
864   PetscFunctionReturn(0);
865 }
866 
867 #undef __FUNCT__
868 #define __FUNCT__ "MatZeroRowsColumns_MPIAIJ"
869 PetscErrorCode MatZeroRowsColumns_MPIAIJ(Mat A,PetscInt N,const PetscInt rows[],PetscScalar diag,Vec x,Vec b)
870 {
871   Mat_MPIAIJ        *l = (Mat_MPIAIJ*)A->data;
872   PetscErrorCode    ierr;
873   PetscMPIInt       n = A->rmap->n;
874   PetscInt          i,j,r,m,p = 0,len = 0;
875   PetscInt          *lrows,*owners = A->rmap->range;
876   PetscSFNode       *rrows;
877   PetscSF           sf;
878   const PetscScalar *xx;
879   PetscScalar       *bb,*mask;
880   Vec               xmask,lmask;
881   Mat_SeqAIJ        *aij = (Mat_SeqAIJ*)l->B->data;
882   const PetscInt    *aj, *ii,*ridx;
883   PetscScalar       *aa;
884 
885   PetscFunctionBegin;
886   /* Create SF where leaves are input rows and roots are owned rows */
887   ierr = PetscMalloc1(n, &lrows);CHKERRQ(ierr);
888   for (r = 0; r < n; ++r) lrows[r] = -1;
889   ierr = PetscMalloc1(N, &rrows);CHKERRQ(ierr);
890   for (r = 0; r < N; ++r) {
891     const PetscInt idx   = rows[r];
892     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);
893     if (idx < owners[p] || owners[p+1] <= idx) { /* short-circuit the search if the last p owns this row too */
894       ierr = PetscLayoutFindOwner(A->rmap,idx,&p);CHKERRQ(ierr);
895     }
896     rrows[r].rank  = p;
897     rrows[r].index = rows[r] - owners[p];
898   }
899   ierr = PetscSFCreate(PetscObjectComm((PetscObject) A), &sf);CHKERRQ(ierr);
900   ierr = PetscSFSetGraph(sf, n, N, NULL, PETSC_OWN_POINTER, rrows, PETSC_OWN_POINTER);CHKERRQ(ierr);
901   /* Collect flags for rows to be zeroed */
902   ierr = PetscSFReduceBegin(sf, MPIU_INT, (PetscInt *) rows, lrows, MPI_LOR);CHKERRQ(ierr);
903   ierr = PetscSFReduceEnd(sf, MPIU_INT, (PetscInt *) rows, lrows, MPI_LOR);CHKERRQ(ierr);
904   ierr = PetscSFDestroy(&sf);CHKERRQ(ierr);
905   /* Compress and put in row numbers */
906   for (r = 0; r < n; ++r) if (lrows[r] >= 0) lrows[len++] = r;
907   /* zero diagonal part of matrix */
908   ierr = MatZeroRowsColumns(l->A,len,lrows,diag,x,b);CHKERRQ(ierr);
909   /* handle off diagonal part of matrix */
910   ierr = MatCreateVecs(A,&xmask,NULL);CHKERRQ(ierr);
911   ierr = VecDuplicate(l->lvec,&lmask);CHKERRQ(ierr);
912   ierr = VecGetArray(xmask,&bb);CHKERRQ(ierr);
913   for (i=0; i<len; i++) bb[lrows[i]] = 1;
914   ierr = VecRestoreArray(xmask,&bb);CHKERRQ(ierr);
915   ierr = VecScatterBegin(l->Mvctx,xmask,lmask,ADD_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
916   ierr = VecScatterEnd(l->Mvctx,xmask,lmask,ADD_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
917   ierr = VecDestroy(&xmask);CHKERRQ(ierr);
918   if (x) {
919     ierr = VecScatterBegin(l->Mvctx,x,l->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
920     ierr = VecScatterEnd(l->Mvctx,x,l->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
921     ierr = VecGetArrayRead(l->lvec,&xx);CHKERRQ(ierr);
922     ierr = VecGetArray(b,&bb);CHKERRQ(ierr);
923   }
924   ierr = VecGetArray(lmask,&mask);CHKERRQ(ierr);
925   /* remove zeroed rows of off diagonal matrix */
926   ii = aij->i;
927   for (i=0; i<len; i++) {
928     ierr = PetscMemzero(aij->a + ii[lrows[i]],(ii[lrows[i]+1] - ii[lrows[i]])*sizeof(PetscScalar));CHKERRQ(ierr);
929   }
930   /* loop over all elements of off process part of matrix zeroing removed columns*/
931   if (aij->compressedrow.use) {
932     m    = aij->compressedrow.nrows;
933     ii   = aij->compressedrow.i;
934     ridx = aij->compressedrow.rindex;
935     for (i=0; i<m; i++) {
936       n  = ii[i+1] - ii[i];
937       aj = aij->j + ii[i];
938       aa = aij->a + ii[i];
939 
940       for (j=0; j<n; j++) {
941         if (PetscAbsScalar(mask[*aj])) {
942           if (b) bb[*ridx] -= *aa*xx[*aj];
943           *aa = 0.0;
944         }
945         aa++;
946         aj++;
947       }
948       ridx++;
949     }
950   } else { /* do not use compressed row format */
951     m = l->B->rmap->n;
952     for (i=0; i<m; i++) {
953       n  = ii[i+1] - ii[i];
954       aj = aij->j + ii[i];
955       aa = aij->a + ii[i];
956       for (j=0; j<n; j++) {
957         if (PetscAbsScalar(mask[*aj])) {
958           if (b) bb[i] -= *aa*xx[*aj];
959           *aa = 0.0;
960         }
961         aa++;
962         aj++;
963       }
964     }
965   }
966   if (x) {
967     ierr = VecRestoreArray(b,&bb);CHKERRQ(ierr);
968     ierr = VecRestoreArrayRead(l->lvec,&xx);CHKERRQ(ierr);
969   }
970   ierr = VecRestoreArray(lmask,&mask);CHKERRQ(ierr);
971   ierr = VecDestroy(&lmask);CHKERRQ(ierr);
972   ierr = PetscFree(lrows);CHKERRQ(ierr);
973 
974   /* only change matrix nonzero state if pattern was allowed to be changed */
975   if (!((Mat_SeqAIJ*)(l->A->data))->keepnonzeropattern) {
976     PetscObjectState state = l->A->nonzerostate + l->B->nonzerostate;
977     ierr = MPI_Allreduce(&state,&A->nonzerostate,1,MPIU_INT64,MPI_SUM,PetscObjectComm((PetscObject)A));CHKERRQ(ierr);
978   }
979   PetscFunctionReturn(0);
980 }
981 
982 #undef __FUNCT__
983 #define __FUNCT__ "MatMult_MPIAIJ"
984 PetscErrorCode MatMult_MPIAIJ(Mat A,Vec xx,Vec yy)
985 {
986   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
987   PetscErrorCode ierr;
988   PetscInt       nt;
989 
990   PetscFunctionBegin;
991   ierr = VecGetLocalSize(xx,&nt);CHKERRQ(ierr);
992   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);
993   ierr = VecScatterBegin(a->Mvctx,xx,a->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
994   ierr = (*a->A->ops->mult)(a->A,xx,yy);CHKERRQ(ierr);
995   ierr = VecScatterEnd(a->Mvctx,xx,a->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
996   ierr = (*a->B->ops->multadd)(a->B,a->lvec,yy,yy);CHKERRQ(ierr);
997   PetscFunctionReturn(0);
998 }
999 
1000 #undef __FUNCT__
1001 #define __FUNCT__ "MatMultDiagonalBlock_MPIAIJ"
1002 PetscErrorCode MatMultDiagonalBlock_MPIAIJ(Mat A,Vec bb,Vec xx)
1003 {
1004   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
1005   PetscErrorCode ierr;
1006 
1007   PetscFunctionBegin;
1008   ierr = MatMultDiagonalBlock(a->A,bb,xx);CHKERRQ(ierr);
1009   PetscFunctionReturn(0);
1010 }
1011 
1012 #undef __FUNCT__
1013 #define __FUNCT__ "MatMultAdd_MPIAIJ"
1014 PetscErrorCode MatMultAdd_MPIAIJ(Mat A,Vec xx,Vec yy,Vec zz)
1015 {
1016   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
1017   PetscErrorCode ierr;
1018 
1019   PetscFunctionBegin;
1020   ierr = VecScatterBegin(a->Mvctx,xx,a->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1021   ierr = (*a->A->ops->multadd)(a->A,xx,yy,zz);CHKERRQ(ierr);
1022   ierr = VecScatterEnd(a->Mvctx,xx,a->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1023   ierr = (*a->B->ops->multadd)(a->B,a->lvec,zz,zz);CHKERRQ(ierr);
1024   PetscFunctionReturn(0);
1025 }
1026 
1027 #undef __FUNCT__
1028 #define __FUNCT__ "MatMultTranspose_MPIAIJ"
1029 PetscErrorCode MatMultTranspose_MPIAIJ(Mat A,Vec xx,Vec yy)
1030 {
1031   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
1032   PetscErrorCode ierr;
1033   PetscBool      merged;
1034 
1035   PetscFunctionBegin;
1036   ierr = VecScatterGetMerged(a->Mvctx,&merged);CHKERRQ(ierr);
1037   /* do nondiagonal part */
1038   ierr = (*a->B->ops->multtranspose)(a->B,xx,a->lvec);CHKERRQ(ierr);
1039   if (!merged) {
1040     /* send it on its way */
1041     ierr = VecScatterBegin(a->Mvctx,a->lvec,yy,ADD_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
1042     /* do local part */
1043     ierr = (*a->A->ops->multtranspose)(a->A,xx,yy);CHKERRQ(ierr);
1044     /* receive remote parts: note this assumes the values are not actually */
1045     /* added in yy until the next line, */
1046     ierr = VecScatterEnd(a->Mvctx,a->lvec,yy,ADD_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
1047   } else {
1048     /* do local part */
1049     ierr = (*a->A->ops->multtranspose)(a->A,xx,yy);CHKERRQ(ierr);
1050     /* send it on its way */
1051     ierr = VecScatterBegin(a->Mvctx,a->lvec,yy,ADD_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
1052     /* values actually were received in the Begin() but we need to call this nop */
1053     ierr = VecScatterEnd(a->Mvctx,a->lvec,yy,ADD_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
1054   }
1055   PetscFunctionReturn(0);
1056 }
1057 
1058 #undef __FUNCT__
1059 #define __FUNCT__ "MatIsTranspose_MPIAIJ"
1060 PetscErrorCode  MatIsTranspose_MPIAIJ(Mat Amat,Mat Bmat,PetscReal tol,PetscBool  *f)
1061 {
1062   MPI_Comm       comm;
1063   Mat_MPIAIJ     *Aij = (Mat_MPIAIJ*) Amat->data, *Bij;
1064   Mat            Adia = Aij->A, Bdia, Aoff,Boff,*Aoffs,*Boffs;
1065   IS             Me,Notme;
1066   PetscErrorCode ierr;
1067   PetscInt       M,N,first,last,*notme,i;
1068   PetscMPIInt    size;
1069 
1070   PetscFunctionBegin;
1071   /* Easy test: symmetric diagonal block */
1072   Bij  = (Mat_MPIAIJ*) Bmat->data; Bdia = Bij->A;
1073   ierr = MatIsTranspose(Adia,Bdia,tol,f);CHKERRQ(ierr);
1074   if (!*f) PetscFunctionReturn(0);
1075   ierr = PetscObjectGetComm((PetscObject)Amat,&comm);CHKERRQ(ierr);
1076   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
1077   if (size == 1) PetscFunctionReturn(0);
1078 
1079   /* Hard test: off-diagonal block. This takes a MatGetSubMatrix. */
1080   ierr = MatGetSize(Amat,&M,&N);CHKERRQ(ierr);
1081   ierr = MatGetOwnershipRange(Amat,&first,&last);CHKERRQ(ierr);
1082   ierr = PetscMalloc1(N-last+first,&notme);CHKERRQ(ierr);
1083   for (i=0; i<first; i++) notme[i] = i;
1084   for (i=last; i<M; i++) notme[i-last+first] = i;
1085   ierr = ISCreateGeneral(MPI_COMM_SELF,N-last+first,notme,PETSC_COPY_VALUES,&Notme);CHKERRQ(ierr);
1086   ierr = ISCreateStride(MPI_COMM_SELF,last-first,first,1,&Me);CHKERRQ(ierr);
1087   ierr = MatGetSubMatrices(Amat,1,&Me,&Notme,MAT_INITIAL_MATRIX,&Aoffs);CHKERRQ(ierr);
1088   Aoff = Aoffs[0];
1089   ierr = MatGetSubMatrices(Bmat,1,&Notme,&Me,MAT_INITIAL_MATRIX,&Boffs);CHKERRQ(ierr);
1090   Boff = Boffs[0];
1091   ierr = MatIsTranspose(Aoff,Boff,tol,f);CHKERRQ(ierr);
1092   ierr = MatDestroyMatrices(1,&Aoffs);CHKERRQ(ierr);
1093   ierr = MatDestroyMatrices(1,&Boffs);CHKERRQ(ierr);
1094   ierr = ISDestroy(&Me);CHKERRQ(ierr);
1095   ierr = ISDestroy(&Notme);CHKERRQ(ierr);
1096   ierr = PetscFree(notme);CHKERRQ(ierr);
1097   PetscFunctionReturn(0);
1098 }
1099 
1100 #undef __FUNCT__
1101 #define __FUNCT__ "MatMultTransposeAdd_MPIAIJ"
1102 PetscErrorCode MatMultTransposeAdd_MPIAIJ(Mat A,Vec xx,Vec yy,Vec zz)
1103 {
1104   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
1105   PetscErrorCode ierr;
1106 
1107   PetscFunctionBegin;
1108   /* do nondiagonal part */
1109   ierr = (*a->B->ops->multtranspose)(a->B,xx,a->lvec);CHKERRQ(ierr);
1110   /* send it on its way */
1111   ierr = VecScatterBegin(a->Mvctx,a->lvec,zz,ADD_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
1112   /* do local part */
1113   ierr = (*a->A->ops->multtransposeadd)(a->A,xx,yy,zz);CHKERRQ(ierr);
1114   /* receive remote parts */
1115   ierr = VecScatterEnd(a->Mvctx,a->lvec,zz,ADD_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
1116   PetscFunctionReturn(0);
1117 }
1118 
1119 /*
1120   This only works correctly for square matrices where the subblock A->A is the
1121    diagonal block
1122 */
1123 #undef __FUNCT__
1124 #define __FUNCT__ "MatGetDiagonal_MPIAIJ"
1125 PetscErrorCode MatGetDiagonal_MPIAIJ(Mat A,Vec v)
1126 {
1127   PetscErrorCode ierr;
1128   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
1129 
1130   PetscFunctionBegin;
1131   if (A->rmap->N != A->cmap->N) SETERRQ(PetscObjectComm((PetscObject)A),PETSC_ERR_SUP,"Supports only square matrix where A->A is diag block");
1132   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");
1133   ierr = MatGetDiagonal(a->A,v);CHKERRQ(ierr);
1134   PetscFunctionReturn(0);
1135 }
1136 
1137 #undef __FUNCT__
1138 #define __FUNCT__ "MatScale_MPIAIJ"
1139 PetscErrorCode MatScale_MPIAIJ(Mat A,PetscScalar aa)
1140 {
1141   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
1142   PetscErrorCode ierr;
1143 
1144   PetscFunctionBegin;
1145   ierr = MatScale(a->A,aa);CHKERRQ(ierr);
1146   ierr = MatScale(a->B,aa);CHKERRQ(ierr);
1147   PetscFunctionReturn(0);
1148 }
1149 
1150 #undef __FUNCT__
1151 #define __FUNCT__ "MatDestroy_MPIAIJ"
1152 PetscErrorCode MatDestroy_MPIAIJ(Mat mat)
1153 {
1154   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
1155   PetscErrorCode ierr;
1156 
1157   PetscFunctionBegin;
1158 #if defined(PETSC_USE_LOG)
1159   PetscLogObjectState((PetscObject)mat,"Rows=%D, Cols=%D",mat->rmap->N,mat->cmap->N);
1160 #endif
1161   ierr = MatStashDestroy_Private(&mat->stash);CHKERRQ(ierr);
1162   ierr = VecDestroy(&aij->diag);CHKERRQ(ierr);
1163   ierr = MatDestroy(&aij->A);CHKERRQ(ierr);
1164   ierr = MatDestroy(&aij->B);CHKERRQ(ierr);
1165 #if defined(PETSC_USE_CTABLE)
1166   ierr = PetscTableDestroy(&aij->colmap);CHKERRQ(ierr);
1167 #else
1168   ierr = PetscFree(aij->colmap);CHKERRQ(ierr);
1169 #endif
1170   ierr = PetscFree(aij->garray);CHKERRQ(ierr);
1171   ierr = VecDestroy(&aij->lvec);CHKERRQ(ierr);
1172   ierr = VecScatterDestroy(&aij->Mvctx);CHKERRQ(ierr);
1173   ierr = PetscFree2(aij->rowvalues,aij->rowindices);CHKERRQ(ierr);
1174   ierr = PetscFree(aij->ld);CHKERRQ(ierr);
1175   ierr = PetscFree(mat->data);CHKERRQ(ierr);
1176 
1177   ierr = PetscObjectChangeTypeName((PetscObject)mat,0);CHKERRQ(ierr);
1178   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatStoreValues_C",NULL);CHKERRQ(ierr);
1179   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatRetrieveValues_C",NULL);CHKERRQ(ierr);
1180   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatGetDiagonalBlock_C",NULL);CHKERRQ(ierr);
1181   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatIsTranspose_C",NULL);CHKERRQ(ierr);
1182   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatMPIAIJSetPreallocation_C",NULL);CHKERRQ(ierr);
1183   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatMPIAIJSetPreallocationCSR_C",NULL);CHKERRQ(ierr);
1184   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatDiagonalScaleLocal_C",NULL);CHKERRQ(ierr);
1185   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatConvert_mpiaij_mpisbaij_C",NULL);CHKERRQ(ierr);
1186 #if defined(PETSC_HAVE_ELEMENTAL)
1187   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatConvert_mpiaij_elemental_C",NULL);CHKERRQ(ierr);
1188 #endif
1189   PetscFunctionReturn(0);
1190 }
1191 
1192 #undef __FUNCT__
1193 #define __FUNCT__ "MatView_MPIAIJ_Binary"
1194 PetscErrorCode MatView_MPIAIJ_Binary(Mat mat,PetscViewer viewer)
1195 {
1196   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
1197   Mat_SeqAIJ     *A   = (Mat_SeqAIJ*)aij->A->data;
1198   Mat_SeqAIJ     *B   = (Mat_SeqAIJ*)aij->B->data;
1199   PetscErrorCode ierr;
1200   PetscMPIInt    rank,size,tag = ((PetscObject)viewer)->tag;
1201   int            fd;
1202   PetscInt       nz,header[4],*row_lengths,*range=0,rlen,i;
1203   PetscInt       nzmax,*column_indices,j,k,col,*garray = aij->garray,cnt,cstart = mat->cmap->rstart,rnz = 0;
1204   PetscScalar    *column_values;
1205   PetscInt       message_count,flowcontrolcount;
1206   FILE           *file;
1207 
1208   PetscFunctionBegin;
1209   ierr = MPI_Comm_rank(PetscObjectComm((PetscObject)mat),&rank);CHKERRQ(ierr);
1210   ierr = MPI_Comm_size(PetscObjectComm((PetscObject)mat),&size);CHKERRQ(ierr);
1211   nz   = A->nz + B->nz;
1212   ierr = PetscViewerBinaryGetDescriptor(viewer,&fd);CHKERRQ(ierr);
1213   if (!rank) {
1214     header[0] = MAT_FILE_CLASSID;
1215     header[1] = mat->rmap->N;
1216     header[2] = mat->cmap->N;
1217 
1218     ierr = MPI_Reduce(&nz,&header[3],1,MPIU_INT,MPI_SUM,0,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1219     ierr = PetscBinaryWrite(fd,header,4,PETSC_INT,PETSC_TRUE);CHKERRQ(ierr);
1220     /* get largest number of rows any processor has */
1221     rlen  = mat->rmap->n;
1222     range = mat->rmap->range;
1223     for (i=1; i<size; i++) rlen = PetscMax(rlen,range[i+1] - range[i]);
1224   } else {
1225     ierr = MPI_Reduce(&nz,0,1,MPIU_INT,MPI_SUM,0,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1226     rlen = mat->rmap->n;
1227   }
1228 
1229   /* load up the local row counts */
1230   ierr = PetscMalloc1(rlen+1,&row_lengths);CHKERRQ(ierr);
1231   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];
1232 
1233   /* store the row lengths to the file */
1234   ierr = PetscViewerFlowControlStart(viewer,&message_count,&flowcontrolcount);CHKERRQ(ierr);
1235   if (!rank) {
1236     ierr = PetscBinaryWrite(fd,row_lengths,mat->rmap->n,PETSC_INT,PETSC_TRUE);CHKERRQ(ierr);
1237     for (i=1; i<size; i++) {
1238       ierr = PetscViewerFlowControlStepMaster(viewer,i,&message_count,flowcontrolcount);CHKERRQ(ierr);
1239       rlen = range[i+1] - range[i];
1240       ierr = MPIULong_Recv(row_lengths,rlen,MPIU_INT,i,tag,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1241       ierr = PetscBinaryWrite(fd,row_lengths,rlen,PETSC_INT,PETSC_TRUE);CHKERRQ(ierr);
1242     }
1243     ierr = PetscViewerFlowControlEndMaster(viewer,&message_count);CHKERRQ(ierr);
1244   } else {
1245     ierr = PetscViewerFlowControlStepWorker(viewer,rank,&message_count);CHKERRQ(ierr);
1246     ierr = MPIULong_Send(row_lengths,mat->rmap->n,MPIU_INT,0,tag,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1247     ierr = PetscViewerFlowControlEndWorker(viewer,&message_count);CHKERRQ(ierr);
1248   }
1249   ierr = PetscFree(row_lengths);CHKERRQ(ierr);
1250 
1251   /* load up the local column indices */
1252   nzmax = nz; /* th processor needs space a largest processor needs */
1253   ierr  = MPI_Reduce(&nz,&nzmax,1,MPIU_INT,MPI_MAX,0,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1254   ierr  = PetscMalloc1(nzmax+1,&column_indices);CHKERRQ(ierr);
1255   cnt   = 0;
1256   for (i=0; i<mat->rmap->n; i++) {
1257     for (j=B->i[i]; j<B->i[i+1]; j++) {
1258       if ((col = garray[B->j[j]]) > cstart) break;
1259       column_indices[cnt++] = col;
1260     }
1261     for (k=A->i[i]; k<A->i[i+1]; k++) column_indices[cnt++] = A->j[k] + cstart;
1262     for (; j<B->i[i+1]; j++) column_indices[cnt++] = garray[B->j[j]];
1263   }
1264   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);
1265 
1266   /* store the column indices to the file */
1267   ierr = PetscViewerFlowControlStart(viewer,&message_count,&flowcontrolcount);CHKERRQ(ierr);
1268   if (!rank) {
1269     MPI_Status status;
1270     ierr = PetscBinaryWrite(fd,column_indices,nz,PETSC_INT,PETSC_TRUE);CHKERRQ(ierr);
1271     for (i=1; i<size; i++) {
1272       ierr = PetscViewerFlowControlStepMaster(viewer,i,&message_count,flowcontrolcount);CHKERRQ(ierr);
1273       ierr = MPI_Recv(&rnz,1,MPIU_INT,i,tag,PetscObjectComm((PetscObject)mat),&status);CHKERRQ(ierr);
1274       if (rnz > nzmax) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_LIB,"Internal PETSc error: nz = %D nzmax = %D",nz,nzmax);
1275       ierr = MPIULong_Recv(column_indices,rnz,MPIU_INT,i,tag,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1276       ierr = PetscBinaryWrite(fd,column_indices,rnz,PETSC_INT,PETSC_TRUE);CHKERRQ(ierr);
1277     }
1278     ierr = PetscViewerFlowControlEndMaster(viewer,&message_count);CHKERRQ(ierr);
1279   } else {
1280     ierr = PetscViewerFlowControlStepWorker(viewer,rank,&message_count);CHKERRQ(ierr);
1281     ierr = MPI_Send(&nz,1,MPIU_INT,0,tag,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1282     ierr = MPIULong_Send(column_indices,nz,MPIU_INT,0,tag,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1283     ierr = PetscViewerFlowControlEndWorker(viewer,&message_count);CHKERRQ(ierr);
1284   }
1285   ierr = PetscFree(column_indices);CHKERRQ(ierr);
1286 
1287   /* load up the local column values */
1288   ierr = PetscMalloc1(nzmax+1,&column_values);CHKERRQ(ierr);
1289   cnt  = 0;
1290   for (i=0; i<mat->rmap->n; i++) {
1291     for (j=B->i[i]; j<B->i[i+1]; j++) {
1292       if (garray[B->j[j]] > cstart) break;
1293       column_values[cnt++] = B->a[j];
1294     }
1295     for (k=A->i[i]; k<A->i[i+1]; k++) column_values[cnt++] = A->a[k];
1296     for (; j<B->i[i+1]; j++) column_values[cnt++] = B->a[j];
1297   }
1298   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);
1299 
1300   /* store the column values to the file */
1301   ierr = PetscViewerFlowControlStart(viewer,&message_count,&flowcontrolcount);CHKERRQ(ierr);
1302   if (!rank) {
1303     MPI_Status status;
1304     ierr = PetscBinaryWrite(fd,column_values,nz,PETSC_SCALAR,PETSC_TRUE);CHKERRQ(ierr);
1305     for (i=1; i<size; i++) {
1306       ierr = PetscViewerFlowControlStepMaster(viewer,i,&message_count,flowcontrolcount);CHKERRQ(ierr);
1307       ierr = MPI_Recv(&rnz,1,MPIU_INT,i,tag,PetscObjectComm((PetscObject)mat),&status);CHKERRQ(ierr);
1308       if (rnz > nzmax) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_LIB,"Internal PETSc error: nz = %D nzmax = %D",nz,nzmax);
1309       ierr = MPIULong_Recv(column_values,rnz,MPIU_SCALAR,i,tag,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1310       ierr = PetscBinaryWrite(fd,column_values,rnz,PETSC_SCALAR,PETSC_TRUE);CHKERRQ(ierr);
1311     }
1312     ierr = PetscViewerFlowControlEndMaster(viewer,&message_count);CHKERRQ(ierr);
1313   } else {
1314     ierr = PetscViewerFlowControlStepWorker(viewer,rank,&message_count);CHKERRQ(ierr);
1315     ierr = MPI_Send(&nz,1,MPIU_INT,0,tag,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1316     ierr = MPIULong_Send(column_values,nz,MPIU_SCALAR,0,tag,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1317     ierr = PetscViewerFlowControlEndWorker(viewer,&message_count);CHKERRQ(ierr);
1318   }
1319   ierr = PetscFree(column_values);CHKERRQ(ierr);
1320 
1321   ierr = PetscViewerBinaryGetInfoPointer(viewer,&file);CHKERRQ(ierr);
1322   if (file) fprintf(file,"-matload_block_size %d\n",(int)PetscAbs(mat->rmap->bs));
1323   PetscFunctionReturn(0);
1324 }
1325 
1326 #include <petscdraw.h>
1327 #undef __FUNCT__
1328 #define __FUNCT__ "MatView_MPIAIJ_ASCIIorDraworSocket"
1329 PetscErrorCode MatView_MPIAIJ_ASCIIorDraworSocket(Mat mat,PetscViewer viewer)
1330 {
1331   Mat_MPIAIJ        *aij = (Mat_MPIAIJ*)mat->data;
1332   PetscErrorCode    ierr;
1333   PetscMPIInt       rank = aij->rank,size = aij->size;
1334   PetscBool         isdraw,iascii,isbinary;
1335   PetscViewer       sviewer;
1336   PetscViewerFormat format;
1337 
1338   PetscFunctionBegin;
1339   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERDRAW,&isdraw);CHKERRQ(ierr);
1340   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERASCII,&iascii);CHKERRQ(ierr);
1341   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERBINARY,&isbinary);CHKERRQ(ierr);
1342   if (iascii) {
1343     ierr = PetscViewerGetFormat(viewer,&format);CHKERRQ(ierr);
1344     if (format == PETSC_VIEWER_ASCII_INFO_DETAIL) {
1345       MatInfo   info;
1346       PetscBool inodes;
1347 
1348       ierr = MPI_Comm_rank(PetscObjectComm((PetscObject)mat),&rank);CHKERRQ(ierr);
1349       ierr = MatGetInfo(mat,MAT_LOCAL,&info);CHKERRQ(ierr);
1350       ierr = MatInodeGetInodeSizes(aij->A,NULL,(PetscInt**)&inodes,NULL);CHKERRQ(ierr);
1351       ierr = PetscViewerASCIISynchronizedAllow(viewer,PETSC_TRUE);CHKERRQ(ierr);
1352       if (!inodes) {
1353         ierr = PetscViewerASCIISynchronizedPrintf(viewer,"[%d] Local rows %D nz %D nz alloced %D mem %D, not using I-node routines\n",
1354                                                   rank,mat->rmap->n,(PetscInt)info.nz_used,(PetscInt)info.nz_allocated,(PetscInt)info.memory);CHKERRQ(ierr);
1355       } else {
1356         ierr = PetscViewerASCIISynchronizedPrintf(viewer,"[%d] Local rows %D nz %D nz alloced %D mem %D, using I-node routines\n",
1357                                                   rank,mat->rmap->n,(PetscInt)info.nz_used,(PetscInt)info.nz_allocated,(PetscInt)info.memory);CHKERRQ(ierr);
1358       }
1359       ierr = MatGetInfo(aij->A,MAT_LOCAL,&info);CHKERRQ(ierr);
1360       ierr = PetscViewerASCIISynchronizedPrintf(viewer,"[%d] on-diagonal part: nz %D \n",rank,(PetscInt)info.nz_used);CHKERRQ(ierr);
1361       ierr = MatGetInfo(aij->B,MAT_LOCAL,&info);CHKERRQ(ierr);
1362       ierr = PetscViewerASCIISynchronizedPrintf(viewer,"[%d] off-diagonal part: nz %D \n",rank,(PetscInt)info.nz_used);CHKERRQ(ierr);
1363       ierr = PetscViewerFlush(viewer);CHKERRQ(ierr);
1364       ierr = PetscViewerASCIISynchronizedAllow(viewer,PETSC_FALSE);CHKERRQ(ierr);
1365       ierr = PetscViewerASCIIPrintf(viewer,"Information on VecScatter used in matrix-vector product: \n");CHKERRQ(ierr);
1366       ierr = VecScatterView(aij->Mvctx,viewer);CHKERRQ(ierr);
1367       PetscFunctionReturn(0);
1368     } else if (format == PETSC_VIEWER_ASCII_INFO) {
1369       PetscInt inodecount,inodelimit,*inodes;
1370       ierr = MatInodeGetInodeSizes(aij->A,&inodecount,&inodes,&inodelimit);CHKERRQ(ierr);
1371       if (inodes) {
1372         ierr = PetscViewerASCIIPrintf(viewer,"using I-node (on process 0) routines: found %D nodes, limit used is %D\n",inodecount,inodelimit);CHKERRQ(ierr);
1373       } else {
1374         ierr = PetscViewerASCIIPrintf(viewer,"not using I-node (on process 0) routines\n");CHKERRQ(ierr);
1375       }
1376       PetscFunctionReturn(0);
1377     } else if (format == PETSC_VIEWER_ASCII_FACTOR_INFO) {
1378       PetscFunctionReturn(0);
1379     }
1380   } else if (isbinary) {
1381     if (size == 1) {
1382       ierr = PetscObjectSetName((PetscObject)aij->A,((PetscObject)mat)->name);CHKERRQ(ierr);
1383       ierr = MatView(aij->A,viewer);CHKERRQ(ierr);
1384     } else {
1385       ierr = MatView_MPIAIJ_Binary(mat,viewer);CHKERRQ(ierr);
1386     }
1387     PetscFunctionReturn(0);
1388   } else if (isdraw) {
1389     PetscDraw draw;
1390     PetscBool isnull;
1391     ierr = PetscViewerDrawGetDraw(viewer,0,&draw);CHKERRQ(ierr);
1392     ierr = PetscDrawIsNull(draw,&isnull);CHKERRQ(ierr); if (isnull) PetscFunctionReturn(0);
1393   }
1394 
1395   {
1396     /* assemble the entire matrix onto first processor. */
1397     Mat        A;
1398     Mat_SeqAIJ *Aloc;
1399     PetscInt   M = mat->rmap->N,N = mat->cmap->N,m,*ai,*aj,row,*cols,i,*ct;
1400     MatScalar  *a;
1401 
1402     ierr = MatCreate(PetscObjectComm((PetscObject)mat),&A);CHKERRQ(ierr);
1403     if (!rank) {
1404       ierr = MatSetSizes(A,M,N,M,N);CHKERRQ(ierr);
1405     } else {
1406       ierr = MatSetSizes(A,0,0,M,N);CHKERRQ(ierr);
1407     }
1408     /* This is just a temporary matrix, so explicitly using MATMPIAIJ is probably best */
1409     ierr = MatSetType(A,MATMPIAIJ);CHKERRQ(ierr);
1410     ierr = MatMPIAIJSetPreallocation(A,0,NULL,0,NULL);CHKERRQ(ierr);
1411     ierr = MatSetOption(A,MAT_NEW_NONZERO_LOCATION_ERR,PETSC_FALSE);CHKERRQ(ierr);
1412     ierr = PetscLogObjectParent((PetscObject)mat,(PetscObject)A);CHKERRQ(ierr);
1413 
1414     /* copy over the A part */
1415     Aloc = (Mat_SeqAIJ*)aij->A->data;
1416     m    = aij->A->rmap->n; ai = Aloc->i; aj = Aloc->j; a = Aloc->a;
1417     row  = mat->rmap->rstart;
1418     for (i=0; i<ai[m]; i++) aj[i] += mat->cmap->rstart;
1419     for (i=0; i<m; i++) {
1420       ierr = MatSetValues(A,1,&row,ai[i+1]-ai[i],aj,a,INSERT_VALUES);CHKERRQ(ierr);
1421       row++;
1422       a += ai[i+1]-ai[i]; aj += ai[i+1]-ai[i];
1423     }
1424     aj = Aloc->j;
1425     for (i=0; i<ai[m]; i++) aj[i] -= mat->cmap->rstart;
1426 
1427     /* copy over the B part */
1428     Aloc = (Mat_SeqAIJ*)aij->B->data;
1429     m    = aij->B->rmap->n;  ai = Aloc->i; aj = Aloc->j; a = Aloc->a;
1430     row  = mat->rmap->rstart;
1431     ierr = PetscMalloc1(ai[m]+1,&cols);CHKERRQ(ierr);
1432     ct   = cols;
1433     for (i=0; i<ai[m]; i++) cols[i] = aij->garray[aj[i]];
1434     for (i=0; i<m; i++) {
1435       ierr = MatSetValues(A,1,&row,ai[i+1]-ai[i],cols,a,INSERT_VALUES);CHKERRQ(ierr);
1436       row++;
1437       a += ai[i+1]-ai[i]; cols += ai[i+1]-ai[i];
1438     }
1439     ierr = PetscFree(ct);CHKERRQ(ierr);
1440     ierr = MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
1441     ierr = MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
1442     /*
1443        Everyone has to call to draw the matrix since the graphics waits are
1444        synchronized across all processors that share the PetscDraw object
1445     */
1446     ierr = PetscViewerGetSingleton(viewer,&sviewer);CHKERRQ(ierr);
1447     if (!rank) {
1448       ierr = PetscObjectSetName((PetscObject)((Mat_MPIAIJ*)(A->data))->A,((PetscObject)mat)->name);CHKERRQ(ierr);
1449       ierr = MatView_SeqAIJ(((Mat_MPIAIJ*)(A->data))->A,sviewer);CHKERRQ(ierr);
1450     }
1451     ierr = PetscViewerRestoreSingleton(viewer,&sviewer);CHKERRQ(ierr);
1452     ierr = MatDestroy(&A);CHKERRQ(ierr);
1453   }
1454   PetscFunctionReturn(0);
1455 }
1456 
1457 #undef __FUNCT__
1458 #define __FUNCT__ "MatView_MPIAIJ"
1459 PetscErrorCode MatView_MPIAIJ(Mat mat,PetscViewer viewer)
1460 {
1461   PetscErrorCode ierr;
1462   PetscBool      iascii,isdraw,issocket,isbinary;
1463 
1464   PetscFunctionBegin;
1465   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERASCII,&iascii);CHKERRQ(ierr);
1466   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERDRAW,&isdraw);CHKERRQ(ierr);
1467   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERBINARY,&isbinary);CHKERRQ(ierr);
1468   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERSOCKET,&issocket);CHKERRQ(ierr);
1469   if (iascii || isdraw || isbinary || issocket) {
1470     ierr = MatView_MPIAIJ_ASCIIorDraworSocket(mat,viewer);CHKERRQ(ierr);
1471   }
1472   PetscFunctionReturn(0);
1473 }
1474 
1475 #undef __FUNCT__
1476 #define __FUNCT__ "MatSOR_MPIAIJ"
1477 PetscErrorCode MatSOR_MPIAIJ(Mat matin,Vec bb,PetscReal omega,MatSORType flag,PetscReal fshift,PetscInt its,PetscInt lits,Vec xx)
1478 {
1479   Mat_MPIAIJ     *mat = (Mat_MPIAIJ*)matin->data;
1480   PetscErrorCode ierr;
1481   Vec            bb1 = 0;
1482   PetscBool      hasop;
1483 
1484   PetscFunctionBegin;
1485   if (flag == SOR_APPLY_UPPER) {
1486     ierr = (*mat->A->ops->sor)(mat->A,bb,omega,flag,fshift,lits,1,xx);CHKERRQ(ierr);
1487     PetscFunctionReturn(0);
1488   }
1489 
1490   if (its > 1 || ~flag & SOR_ZERO_INITIAL_GUESS || flag & SOR_EISENSTAT) {
1491     ierr = VecDuplicate(bb,&bb1);CHKERRQ(ierr);
1492   }
1493 
1494   if ((flag & SOR_LOCAL_SYMMETRIC_SWEEP) == SOR_LOCAL_SYMMETRIC_SWEEP) {
1495     if (flag & SOR_ZERO_INITIAL_GUESS) {
1496       ierr = (*mat->A->ops->sor)(mat->A,bb,omega,flag,fshift,lits,1,xx);CHKERRQ(ierr);
1497       its--;
1498     }
1499 
1500     while (its--) {
1501       ierr = VecScatterBegin(mat->Mvctx,xx,mat->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1502       ierr = VecScatterEnd(mat->Mvctx,xx,mat->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1503 
1504       /* update rhs: bb1 = bb - B*x */
1505       ierr = VecScale(mat->lvec,-1.0);CHKERRQ(ierr);
1506       ierr = (*mat->B->ops->multadd)(mat->B,mat->lvec,bb,bb1);CHKERRQ(ierr);
1507 
1508       /* local sweep */
1509       ierr = (*mat->A->ops->sor)(mat->A,bb1,omega,SOR_SYMMETRIC_SWEEP,fshift,lits,1,xx);CHKERRQ(ierr);
1510     }
1511   } else if (flag & SOR_LOCAL_FORWARD_SWEEP) {
1512     if (flag & SOR_ZERO_INITIAL_GUESS) {
1513       ierr = (*mat->A->ops->sor)(mat->A,bb,omega,flag,fshift,lits,1,xx);CHKERRQ(ierr);
1514       its--;
1515     }
1516     while (its--) {
1517       ierr = VecScatterBegin(mat->Mvctx,xx,mat->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1518       ierr = VecScatterEnd(mat->Mvctx,xx,mat->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1519 
1520       /* update rhs: bb1 = bb - B*x */
1521       ierr = VecScale(mat->lvec,-1.0);CHKERRQ(ierr);
1522       ierr = (*mat->B->ops->multadd)(mat->B,mat->lvec,bb,bb1);CHKERRQ(ierr);
1523 
1524       /* local sweep */
1525       ierr = (*mat->A->ops->sor)(mat->A,bb1,omega,SOR_FORWARD_SWEEP,fshift,lits,1,xx);CHKERRQ(ierr);
1526     }
1527   } else if (flag & SOR_LOCAL_BACKWARD_SWEEP) {
1528     if (flag & SOR_ZERO_INITIAL_GUESS) {
1529       ierr = (*mat->A->ops->sor)(mat->A,bb,omega,flag,fshift,lits,1,xx);CHKERRQ(ierr);
1530       its--;
1531     }
1532     while (its--) {
1533       ierr = VecScatterBegin(mat->Mvctx,xx,mat->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1534       ierr = VecScatterEnd(mat->Mvctx,xx,mat->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1535 
1536       /* update rhs: bb1 = bb - B*x */
1537       ierr = VecScale(mat->lvec,-1.0);CHKERRQ(ierr);
1538       ierr = (*mat->B->ops->multadd)(mat->B,mat->lvec,bb,bb1);CHKERRQ(ierr);
1539 
1540       /* local sweep */
1541       ierr = (*mat->A->ops->sor)(mat->A,bb1,omega,SOR_BACKWARD_SWEEP,fshift,lits,1,xx);CHKERRQ(ierr);
1542     }
1543   } else if (flag & SOR_EISENSTAT) {
1544     Vec xx1;
1545 
1546     ierr = VecDuplicate(bb,&xx1);CHKERRQ(ierr);
1547     ierr = (*mat->A->ops->sor)(mat->A,bb,omega,(MatSORType)(SOR_ZERO_INITIAL_GUESS | SOR_LOCAL_BACKWARD_SWEEP),fshift,lits,1,xx);CHKERRQ(ierr);
1548 
1549     ierr = VecScatterBegin(mat->Mvctx,xx,mat->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1550     ierr = VecScatterEnd(mat->Mvctx,xx,mat->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1551     if (!mat->diag) {
1552       ierr = MatCreateVecs(matin,&mat->diag,NULL);CHKERRQ(ierr);
1553       ierr = MatGetDiagonal(matin,mat->diag);CHKERRQ(ierr);
1554     }
1555     ierr = MatHasOperation(matin,MATOP_MULT_DIAGONAL_BLOCK,&hasop);CHKERRQ(ierr);
1556     if (hasop) {
1557       ierr = MatMultDiagonalBlock(matin,xx,bb1);CHKERRQ(ierr);
1558     } else {
1559       ierr = VecPointwiseMult(bb1,mat->diag,xx);CHKERRQ(ierr);
1560     }
1561     ierr = VecAYPX(bb1,(omega-2.0)/omega,bb);CHKERRQ(ierr);
1562 
1563     ierr = MatMultAdd(mat->B,mat->lvec,bb1,bb1);CHKERRQ(ierr);
1564 
1565     /* local sweep */
1566     ierr = (*mat->A->ops->sor)(mat->A,bb1,omega,(MatSORType)(SOR_ZERO_INITIAL_GUESS | SOR_LOCAL_FORWARD_SWEEP),fshift,lits,1,xx1);CHKERRQ(ierr);
1567     ierr = VecAXPY(xx,1.0,xx1);CHKERRQ(ierr);
1568     ierr = VecDestroy(&xx1);CHKERRQ(ierr);
1569   } else SETERRQ(PetscObjectComm((PetscObject)matin),PETSC_ERR_SUP,"Parallel SOR not supported");
1570 
1571   ierr = VecDestroy(&bb1);CHKERRQ(ierr);
1572   PetscFunctionReturn(0);
1573 }
1574 
1575 #undef __FUNCT__
1576 #define __FUNCT__ "MatPermute_MPIAIJ"
1577 PetscErrorCode MatPermute_MPIAIJ(Mat A,IS rowp,IS colp,Mat *B)
1578 {
1579   Mat            aA,aB,Aperm;
1580   const PetscInt *rwant,*cwant,*gcols,*ai,*bi,*aj,*bj;
1581   PetscScalar    *aa,*ba;
1582   PetscInt       i,j,m,n,ng,anz,bnz,*dnnz,*onnz,*tdnnz,*tonnz,*rdest,*cdest,*work,*gcdest;
1583   PetscSF        rowsf,sf;
1584   IS             parcolp = NULL;
1585   PetscBool      done;
1586   PetscErrorCode ierr;
1587 
1588   PetscFunctionBegin;
1589   ierr = MatGetLocalSize(A,&m,&n);CHKERRQ(ierr);
1590   ierr = ISGetIndices(rowp,&rwant);CHKERRQ(ierr);
1591   ierr = ISGetIndices(colp,&cwant);CHKERRQ(ierr);
1592   ierr = PetscMalloc3(PetscMax(m,n),&work,m,&rdest,n,&cdest);CHKERRQ(ierr);
1593 
1594   /* Invert row permutation to find out where my rows should go */
1595   ierr = PetscSFCreate(PetscObjectComm((PetscObject)A),&rowsf);CHKERRQ(ierr);
1596   ierr = PetscSFSetGraphLayout(rowsf,A->rmap,A->rmap->n,NULL,PETSC_OWN_POINTER,rwant);CHKERRQ(ierr);
1597   ierr = PetscSFSetFromOptions(rowsf);CHKERRQ(ierr);
1598   for (i=0; i<m; i++) work[i] = A->rmap->rstart + i;
1599   ierr = PetscSFReduceBegin(rowsf,MPIU_INT,work,rdest,MPIU_REPLACE);CHKERRQ(ierr);
1600   ierr = PetscSFReduceEnd(rowsf,MPIU_INT,work,rdest,MPIU_REPLACE);CHKERRQ(ierr);
1601 
1602   /* Invert column permutation to find out where my columns should go */
1603   ierr = PetscSFCreate(PetscObjectComm((PetscObject)A),&sf);CHKERRQ(ierr);
1604   ierr = PetscSFSetGraphLayout(sf,A->cmap,A->cmap->n,NULL,PETSC_OWN_POINTER,cwant);CHKERRQ(ierr);
1605   ierr = PetscSFSetFromOptions(sf);CHKERRQ(ierr);
1606   for (i=0; i<n; i++) work[i] = A->cmap->rstart + i;
1607   ierr = PetscSFReduceBegin(sf,MPIU_INT,work,cdest,MPIU_REPLACE);CHKERRQ(ierr);
1608   ierr = PetscSFReduceEnd(sf,MPIU_INT,work,cdest,MPIU_REPLACE);CHKERRQ(ierr);
1609   ierr = PetscSFDestroy(&sf);CHKERRQ(ierr);
1610 
1611   ierr = ISRestoreIndices(rowp,&rwant);CHKERRQ(ierr);
1612   ierr = ISRestoreIndices(colp,&cwant);CHKERRQ(ierr);
1613   ierr = MatMPIAIJGetSeqAIJ(A,&aA,&aB,&gcols);CHKERRQ(ierr);
1614 
1615   /* Find out where my gcols should go */
1616   ierr = MatGetSize(aB,NULL,&ng);CHKERRQ(ierr);
1617   ierr = PetscMalloc1(ng,&gcdest);CHKERRQ(ierr);
1618   ierr = PetscSFCreate(PetscObjectComm((PetscObject)A),&sf);CHKERRQ(ierr);
1619   ierr = PetscSFSetGraphLayout(sf,A->cmap,ng,NULL,PETSC_OWN_POINTER,gcols);CHKERRQ(ierr);
1620   ierr = PetscSFSetFromOptions(sf);CHKERRQ(ierr);
1621   ierr = PetscSFBcastBegin(sf,MPIU_INT,cdest,gcdest);CHKERRQ(ierr);
1622   ierr = PetscSFBcastEnd(sf,MPIU_INT,cdest,gcdest);CHKERRQ(ierr);
1623   ierr = PetscSFDestroy(&sf);CHKERRQ(ierr);
1624 
1625   ierr = PetscCalloc4(m,&dnnz,m,&onnz,m,&tdnnz,m,&tonnz);CHKERRQ(ierr);
1626   ierr = MatGetRowIJ(aA,0,PETSC_FALSE,PETSC_FALSE,&anz,&ai,&aj,&done);CHKERRQ(ierr);
1627   ierr = MatGetRowIJ(aB,0,PETSC_FALSE,PETSC_FALSE,&bnz,&bi,&bj,&done);CHKERRQ(ierr);
1628   for (i=0; i<m; i++) {
1629     PetscInt row = rdest[i],rowner;
1630     ierr = PetscLayoutFindOwner(A->rmap,row,&rowner);CHKERRQ(ierr);
1631     for (j=ai[i]; j<ai[i+1]; j++) {
1632       PetscInt cowner,col = cdest[aj[j]];
1633       ierr = PetscLayoutFindOwner(A->cmap,col,&cowner);CHKERRQ(ierr); /* Could build an index for the columns to eliminate this search */
1634       if (rowner == cowner) dnnz[i]++;
1635       else onnz[i]++;
1636     }
1637     for (j=bi[i]; j<bi[i+1]; j++) {
1638       PetscInt cowner,col = gcdest[bj[j]];
1639       ierr = PetscLayoutFindOwner(A->cmap,col,&cowner);CHKERRQ(ierr);
1640       if (rowner == cowner) dnnz[i]++;
1641       else onnz[i]++;
1642     }
1643   }
1644   ierr = PetscSFBcastBegin(rowsf,MPIU_INT,dnnz,tdnnz);CHKERRQ(ierr);
1645   ierr = PetscSFBcastEnd(rowsf,MPIU_INT,dnnz,tdnnz);CHKERRQ(ierr);
1646   ierr = PetscSFBcastBegin(rowsf,MPIU_INT,onnz,tonnz);CHKERRQ(ierr);
1647   ierr = PetscSFBcastEnd(rowsf,MPIU_INT,onnz,tonnz);CHKERRQ(ierr);
1648   ierr = PetscSFDestroy(&rowsf);CHKERRQ(ierr);
1649 
1650   ierr = MatCreateAIJ(PetscObjectComm((PetscObject)A),A->rmap->n,A->cmap->n,A->rmap->N,A->cmap->N,0,tdnnz,0,tonnz,&Aperm);CHKERRQ(ierr);
1651   ierr = MatSeqAIJGetArray(aA,&aa);CHKERRQ(ierr);
1652   ierr = MatSeqAIJGetArray(aB,&ba);CHKERRQ(ierr);
1653   for (i=0; i<m; i++) {
1654     PetscInt *acols = dnnz,*bcols = onnz; /* Repurpose now-unneeded arrays */
1655     PetscInt j0,rowlen;
1656     rowlen = ai[i+1] - ai[i];
1657     for (j0=j=0; j<rowlen; j0=j) { /* rowlen could be larger than number of rows m, so sum in batches */
1658       for ( ; j<PetscMin(rowlen,j0+m); j++) acols[j-j0] = cdest[aj[ai[i]+j]];
1659       ierr = MatSetValues(Aperm,1,&rdest[i],j-j0,acols,aa+ai[i]+j0,INSERT_VALUES);CHKERRQ(ierr);
1660     }
1661     rowlen = bi[i+1] - bi[i];
1662     for (j0=j=0; j<rowlen; j0=j) {
1663       for ( ; j<PetscMin(rowlen,j0+m); j++) bcols[j-j0] = gcdest[bj[bi[i]+j]];
1664       ierr = MatSetValues(Aperm,1,&rdest[i],j-j0,bcols,ba+bi[i]+j0,INSERT_VALUES);CHKERRQ(ierr);
1665     }
1666   }
1667   ierr = MatAssemblyBegin(Aperm,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
1668   ierr = MatAssemblyEnd(Aperm,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
1669   ierr = MatRestoreRowIJ(aA,0,PETSC_FALSE,PETSC_FALSE,&anz,&ai,&aj,&done);CHKERRQ(ierr);
1670   ierr = MatRestoreRowIJ(aB,0,PETSC_FALSE,PETSC_FALSE,&bnz,&bi,&bj,&done);CHKERRQ(ierr);
1671   ierr = MatSeqAIJRestoreArray(aA,&aa);CHKERRQ(ierr);
1672   ierr = MatSeqAIJRestoreArray(aB,&ba);CHKERRQ(ierr);
1673   ierr = PetscFree4(dnnz,onnz,tdnnz,tonnz);CHKERRQ(ierr);
1674   ierr = PetscFree3(work,rdest,cdest);CHKERRQ(ierr);
1675   ierr = PetscFree(gcdest);CHKERRQ(ierr);
1676   if (parcolp) {ierr = ISDestroy(&colp);CHKERRQ(ierr);}
1677   *B = Aperm;
1678   PetscFunctionReturn(0);
1679 }
1680 
1681 #undef __FUNCT__
1682 #define __FUNCT__ "MatGetInfo_MPIAIJ"
1683 PetscErrorCode MatGetInfo_MPIAIJ(Mat matin,MatInfoType flag,MatInfo *info)
1684 {
1685   Mat_MPIAIJ     *mat = (Mat_MPIAIJ*)matin->data;
1686   Mat            A    = mat->A,B = mat->B;
1687   PetscErrorCode ierr;
1688   PetscReal      isend[5],irecv[5];
1689 
1690   PetscFunctionBegin;
1691   info->block_size = 1.0;
1692   ierr             = MatGetInfo(A,MAT_LOCAL,info);CHKERRQ(ierr);
1693 
1694   isend[0] = info->nz_used; isend[1] = info->nz_allocated; isend[2] = info->nz_unneeded;
1695   isend[3] = info->memory;  isend[4] = info->mallocs;
1696 
1697   ierr = MatGetInfo(B,MAT_LOCAL,info);CHKERRQ(ierr);
1698 
1699   isend[0] += info->nz_used; isend[1] += info->nz_allocated; isend[2] += info->nz_unneeded;
1700   isend[3] += info->memory;  isend[4] += info->mallocs;
1701   if (flag == MAT_LOCAL) {
1702     info->nz_used      = isend[0];
1703     info->nz_allocated = isend[1];
1704     info->nz_unneeded  = isend[2];
1705     info->memory       = isend[3];
1706     info->mallocs      = isend[4];
1707   } else if (flag == MAT_GLOBAL_MAX) {
1708     ierr = MPI_Allreduce(isend,irecv,5,MPIU_REAL,MPIU_MAX,PetscObjectComm((PetscObject)matin));CHKERRQ(ierr);
1709 
1710     info->nz_used      = irecv[0];
1711     info->nz_allocated = irecv[1];
1712     info->nz_unneeded  = irecv[2];
1713     info->memory       = irecv[3];
1714     info->mallocs      = irecv[4];
1715   } else if (flag == MAT_GLOBAL_SUM) {
1716     ierr = MPI_Allreduce(isend,irecv,5,MPIU_REAL,MPIU_SUM,PetscObjectComm((PetscObject)matin));CHKERRQ(ierr);
1717 
1718     info->nz_used      = irecv[0];
1719     info->nz_allocated = irecv[1];
1720     info->nz_unneeded  = irecv[2];
1721     info->memory       = irecv[3];
1722     info->mallocs      = irecv[4];
1723   }
1724   info->fill_ratio_given  = 0; /* no parallel LU/ILU/Cholesky */
1725   info->fill_ratio_needed = 0;
1726   info->factor_mallocs    = 0;
1727   PetscFunctionReturn(0);
1728 }
1729 
1730 #undef __FUNCT__
1731 #define __FUNCT__ "MatSetOption_MPIAIJ"
1732 PetscErrorCode MatSetOption_MPIAIJ(Mat A,MatOption op,PetscBool flg)
1733 {
1734   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
1735   PetscErrorCode ierr;
1736 
1737   PetscFunctionBegin;
1738   switch (op) {
1739   case MAT_NEW_NONZERO_LOCATIONS:
1740   case MAT_NEW_NONZERO_ALLOCATION_ERR:
1741   case MAT_UNUSED_NONZERO_LOCATION_ERR:
1742   case MAT_KEEP_NONZERO_PATTERN:
1743   case MAT_NEW_NONZERO_LOCATION_ERR:
1744   case MAT_USE_INODES:
1745   case MAT_IGNORE_ZERO_ENTRIES:
1746     MatCheckPreallocated(A,1);
1747     ierr = MatSetOption(a->A,op,flg);CHKERRQ(ierr);
1748     ierr = MatSetOption(a->B,op,flg);CHKERRQ(ierr);
1749     break;
1750   case MAT_ROW_ORIENTED:
1751     a->roworiented = flg;
1752 
1753     ierr = MatSetOption(a->A,op,flg);CHKERRQ(ierr);
1754     ierr = MatSetOption(a->B,op,flg);CHKERRQ(ierr);
1755     break;
1756   case MAT_NEW_DIAGONALS:
1757     ierr = PetscInfo1(A,"Option %s ignored\n",MatOptions[op]);CHKERRQ(ierr);
1758     break;
1759   case MAT_IGNORE_OFF_PROC_ENTRIES:
1760     a->donotstash = flg;
1761     break;
1762   case MAT_SPD:
1763     A->spd_set = PETSC_TRUE;
1764     A->spd     = flg;
1765     if (flg) {
1766       A->symmetric                  = PETSC_TRUE;
1767       A->structurally_symmetric     = PETSC_TRUE;
1768       A->symmetric_set              = PETSC_TRUE;
1769       A->structurally_symmetric_set = PETSC_TRUE;
1770     }
1771     break;
1772   case MAT_SYMMETRIC:
1773     ierr = MatSetOption(a->A,op,flg);CHKERRQ(ierr);
1774     break;
1775   case MAT_STRUCTURALLY_SYMMETRIC:
1776     ierr = MatSetOption(a->A,op,flg);CHKERRQ(ierr);
1777     break;
1778   case MAT_HERMITIAN:
1779     ierr = MatSetOption(a->A,op,flg);CHKERRQ(ierr);
1780     break;
1781   case MAT_SYMMETRY_ETERNAL:
1782     ierr = MatSetOption(a->A,op,flg);CHKERRQ(ierr);
1783     break;
1784   default:
1785     SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_SUP,"unknown option %d",op);
1786   }
1787   PetscFunctionReturn(0);
1788 }
1789 
1790 #undef __FUNCT__
1791 #define __FUNCT__ "MatGetRow_MPIAIJ"
1792 PetscErrorCode MatGetRow_MPIAIJ(Mat matin,PetscInt row,PetscInt *nz,PetscInt **idx,PetscScalar **v)
1793 {
1794   Mat_MPIAIJ     *mat = (Mat_MPIAIJ*)matin->data;
1795   PetscScalar    *vworkA,*vworkB,**pvA,**pvB,*v_p;
1796   PetscErrorCode ierr;
1797   PetscInt       i,*cworkA,*cworkB,**pcA,**pcB,cstart = matin->cmap->rstart;
1798   PetscInt       nztot,nzA,nzB,lrow,rstart = matin->rmap->rstart,rend = matin->rmap->rend;
1799   PetscInt       *cmap,*idx_p;
1800 
1801   PetscFunctionBegin;
1802   if (mat->getrowactive) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"Already active");
1803   mat->getrowactive = PETSC_TRUE;
1804 
1805   if (!mat->rowvalues && (idx || v)) {
1806     /*
1807         allocate enough space to hold information from the longest row.
1808     */
1809     Mat_SeqAIJ *Aa = (Mat_SeqAIJ*)mat->A->data,*Ba = (Mat_SeqAIJ*)mat->B->data;
1810     PetscInt   max = 1,tmp;
1811     for (i=0; i<matin->rmap->n; i++) {
1812       tmp = Aa->i[i+1] - Aa->i[i] + Ba->i[i+1] - Ba->i[i];
1813       if (max < tmp) max = tmp;
1814     }
1815     ierr = PetscMalloc2(max,&mat->rowvalues,max,&mat->rowindices);CHKERRQ(ierr);
1816   }
1817 
1818   if (row < rstart || row >= rend) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Only local rows");
1819   lrow = row - rstart;
1820 
1821   pvA = &vworkA; pcA = &cworkA; pvB = &vworkB; pcB = &cworkB;
1822   if (!v)   {pvA = 0; pvB = 0;}
1823   if (!idx) {pcA = 0; if (!v) pcB = 0;}
1824   ierr  = (*mat->A->ops->getrow)(mat->A,lrow,&nzA,pcA,pvA);CHKERRQ(ierr);
1825   ierr  = (*mat->B->ops->getrow)(mat->B,lrow,&nzB,pcB,pvB);CHKERRQ(ierr);
1826   nztot = nzA + nzB;
1827 
1828   cmap = mat->garray;
1829   if (v  || idx) {
1830     if (nztot) {
1831       /* Sort by increasing column numbers, assuming A and B already sorted */
1832       PetscInt imark = -1;
1833       if (v) {
1834         *v = v_p = mat->rowvalues;
1835         for (i=0; i<nzB; i++) {
1836           if (cmap[cworkB[i]] < cstart) v_p[i] = vworkB[i];
1837           else break;
1838         }
1839         imark = i;
1840         for (i=0; i<nzA; i++)     v_p[imark+i] = vworkA[i];
1841         for (i=imark; i<nzB; i++) v_p[nzA+i]   = vworkB[i];
1842       }
1843       if (idx) {
1844         *idx = idx_p = mat->rowindices;
1845         if (imark > -1) {
1846           for (i=0; i<imark; i++) {
1847             idx_p[i] = cmap[cworkB[i]];
1848           }
1849         } else {
1850           for (i=0; i<nzB; i++) {
1851             if (cmap[cworkB[i]] < cstart) idx_p[i] = cmap[cworkB[i]];
1852             else break;
1853           }
1854           imark = i;
1855         }
1856         for (i=0; i<nzA; i++)     idx_p[imark+i] = cstart + cworkA[i];
1857         for (i=imark; i<nzB; i++) idx_p[nzA+i]   = cmap[cworkB[i]];
1858       }
1859     } else {
1860       if (idx) *idx = 0;
1861       if (v)   *v   = 0;
1862     }
1863   }
1864   *nz  = nztot;
1865   ierr = (*mat->A->ops->restorerow)(mat->A,lrow,&nzA,pcA,pvA);CHKERRQ(ierr);
1866   ierr = (*mat->B->ops->restorerow)(mat->B,lrow,&nzB,pcB,pvB);CHKERRQ(ierr);
1867   PetscFunctionReturn(0);
1868 }
1869 
1870 #undef __FUNCT__
1871 #define __FUNCT__ "MatRestoreRow_MPIAIJ"
1872 PetscErrorCode MatRestoreRow_MPIAIJ(Mat mat,PetscInt row,PetscInt *nz,PetscInt **idx,PetscScalar **v)
1873 {
1874   Mat_MPIAIJ *aij = (Mat_MPIAIJ*)mat->data;
1875 
1876   PetscFunctionBegin;
1877   if (!aij->getrowactive) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"MatGetRow() must be called first");
1878   aij->getrowactive = PETSC_FALSE;
1879   PetscFunctionReturn(0);
1880 }
1881 
1882 #undef __FUNCT__
1883 #define __FUNCT__ "MatNorm_MPIAIJ"
1884 PetscErrorCode MatNorm_MPIAIJ(Mat mat,NormType type,PetscReal *norm)
1885 {
1886   Mat_MPIAIJ     *aij  = (Mat_MPIAIJ*)mat->data;
1887   Mat_SeqAIJ     *amat = (Mat_SeqAIJ*)aij->A->data,*bmat = (Mat_SeqAIJ*)aij->B->data;
1888   PetscErrorCode ierr;
1889   PetscInt       i,j,cstart = mat->cmap->rstart;
1890   PetscReal      sum = 0.0;
1891   MatScalar      *v;
1892 
1893   PetscFunctionBegin;
1894   if (aij->size == 1) {
1895     ierr =  MatNorm(aij->A,type,norm);CHKERRQ(ierr);
1896   } else {
1897     if (type == NORM_FROBENIUS) {
1898       v = amat->a;
1899       for (i=0; i<amat->nz; i++) {
1900         sum += PetscRealPart(PetscConj(*v)*(*v)); v++;
1901       }
1902       v = bmat->a;
1903       for (i=0; i<bmat->nz; i++) {
1904         sum += PetscRealPart(PetscConj(*v)*(*v)); v++;
1905       }
1906       ierr  = MPI_Allreduce(&sum,norm,1,MPIU_REAL,MPIU_SUM,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1907       *norm = PetscSqrtReal(*norm);
1908     } else if (type == NORM_1) { /* max column norm */
1909       PetscReal *tmp,*tmp2;
1910       PetscInt  *jj,*garray = aij->garray;
1911       ierr  = PetscCalloc1(mat->cmap->N+1,&tmp);CHKERRQ(ierr);
1912       ierr  = PetscMalloc1(mat->cmap->N+1,&tmp2);CHKERRQ(ierr);
1913       *norm = 0.0;
1914       v     = amat->a; jj = amat->j;
1915       for (j=0; j<amat->nz; j++) {
1916         tmp[cstart + *jj++] += PetscAbsScalar(*v);  v++;
1917       }
1918       v = bmat->a; jj = bmat->j;
1919       for (j=0; j<bmat->nz; j++) {
1920         tmp[garray[*jj++]] += PetscAbsScalar(*v); v++;
1921       }
1922       ierr = MPI_Allreduce(tmp,tmp2,mat->cmap->N,MPIU_REAL,MPIU_SUM,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1923       for (j=0; j<mat->cmap->N; j++) {
1924         if (tmp2[j] > *norm) *norm = tmp2[j];
1925       }
1926       ierr = PetscFree(tmp);CHKERRQ(ierr);
1927       ierr = PetscFree(tmp2);CHKERRQ(ierr);
1928     } else if (type == NORM_INFINITY) { /* max row norm */
1929       PetscReal ntemp = 0.0;
1930       for (j=0; j<aij->A->rmap->n; j++) {
1931         v   = amat->a + amat->i[j];
1932         sum = 0.0;
1933         for (i=0; i<amat->i[j+1]-amat->i[j]; i++) {
1934           sum += PetscAbsScalar(*v); v++;
1935         }
1936         v = bmat->a + bmat->i[j];
1937         for (i=0; i<bmat->i[j+1]-bmat->i[j]; i++) {
1938           sum += PetscAbsScalar(*v); v++;
1939         }
1940         if (sum > ntemp) ntemp = sum;
1941       }
1942       ierr = MPI_Allreduce(&ntemp,norm,1,MPIU_REAL,MPIU_MAX,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1943     } else SETERRQ(PetscObjectComm((PetscObject)mat),PETSC_ERR_SUP,"No support for two norm");
1944   }
1945   PetscFunctionReturn(0);
1946 }
1947 
1948 #undef __FUNCT__
1949 #define __FUNCT__ "MatTranspose_MPIAIJ"
1950 PetscErrorCode MatTranspose_MPIAIJ(Mat A,MatReuse reuse,Mat *matout)
1951 {
1952   Mat_MPIAIJ     *a   = (Mat_MPIAIJ*)A->data;
1953   Mat_SeqAIJ     *Aloc=(Mat_SeqAIJ*)a->A->data,*Bloc=(Mat_SeqAIJ*)a->B->data;
1954   PetscErrorCode ierr;
1955   PetscInt       M      = A->rmap->N,N = A->cmap->N,ma,na,mb,nb,*ai,*aj,*bi,*bj,row,*cols,*cols_tmp,i;
1956   PetscInt       cstart = A->cmap->rstart,ncol;
1957   Mat            B;
1958   MatScalar      *array;
1959 
1960   PetscFunctionBegin;
1961   if (reuse == MAT_REUSE_MATRIX && A == *matout && M != N) SETERRQ(PetscObjectComm((PetscObject)A),PETSC_ERR_ARG_SIZ,"Square matrix only for in-place");
1962 
1963   ma = A->rmap->n; na = A->cmap->n; mb = a->B->rmap->n; nb = a->B->cmap->n;
1964   ai = Aloc->i; aj = Aloc->j;
1965   bi = Bloc->i; bj = Bloc->j;
1966   if (reuse == MAT_INITIAL_MATRIX || *matout == A) {
1967     PetscInt             *d_nnz,*g_nnz,*o_nnz;
1968     PetscSFNode          *oloc;
1969     PETSC_UNUSED PetscSF sf;
1970 
1971     ierr = PetscMalloc4(na,&d_nnz,na,&o_nnz,nb,&g_nnz,nb,&oloc);CHKERRQ(ierr);
1972     /* compute d_nnz for preallocation */
1973     ierr = PetscMemzero(d_nnz,na*sizeof(PetscInt));CHKERRQ(ierr);
1974     for (i=0; i<ai[ma]; i++) {
1975       d_nnz[aj[i]]++;
1976       aj[i] += cstart; /* global col index to be used by MatSetValues() */
1977     }
1978     /* compute local off-diagonal contributions */
1979     ierr = PetscMemzero(g_nnz,nb*sizeof(PetscInt));CHKERRQ(ierr);
1980     for (i=0; i<bi[ma]; i++) g_nnz[bj[i]]++;
1981     /* map those to global */
1982     ierr = PetscSFCreate(PetscObjectComm((PetscObject)A),&sf);CHKERRQ(ierr);
1983     ierr = PetscSFSetGraphLayout(sf,A->cmap,nb,NULL,PETSC_USE_POINTER,a->garray);CHKERRQ(ierr);
1984     ierr = PetscSFSetFromOptions(sf);CHKERRQ(ierr);
1985     ierr = PetscMemzero(o_nnz,na*sizeof(PetscInt));CHKERRQ(ierr);
1986     ierr = PetscSFReduceBegin(sf,MPIU_INT,g_nnz,o_nnz,MPIU_SUM);CHKERRQ(ierr);
1987     ierr = PetscSFReduceEnd(sf,MPIU_INT,g_nnz,o_nnz,MPIU_SUM);CHKERRQ(ierr);
1988     ierr = PetscSFDestroy(&sf);CHKERRQ(ierr);
1989 
1990     ierr = MatCreate(PetscObjectComm((PetscObject)A),&B);CHKERRQ(ierr);
1991     ierr = MatSetSizes(B,A->cmap->n,A->rmap->n,N,M);CHKERRQ(ierr);
1992     ierr = MatSetBlockSizes(B,PetscAbs(A->cmap->bs),PetscAbs(A->rmap->bs));CHKERRQ(ierr);
1993     ierr = MatSetType(B,((PetscObject)A)->type_name);CHKERRQ(ierr);
1994     ierr = MatMPIAIJSetPreallocation(B,0,d_nnz,0,o_nnz);CHKERRQ(ierr);
1995     ierr = PetscFree4(d_nnz,o_nnz,g_nnz,oloc);CHKERRQ(ierr);
1996   } else {
1997     B    = *matout;
1998     ierr = MatSetOption(B,MAT_NEW_NONZERO_ALLOCATION_ERR,PETSC_TRUE);CHKERRQ(ierr);
1999     for (i=0; i<ai[ma]; i++) aj[i] += cstart; /* global col index to be used by MatSetValues() */
2000   }
2001 
2002   /* copy over the A part */
2003   array = Aloc->a;
2004   row   = A->rmap->rstart;
2005   for (i=0; i<ma; i++) {
2006     ncol = ai[i+1]-ai[i];
2007     ierr = MatSetValues(B,ncol,aj,1,&row,array,INSERT_VALUES);CHKERRQ(ierr);
2008     row++;
2009     array += ncol; aj += ncol;
2010   }
2011   aj = Aloc->j;
2012   for (i=0; i<ai[ma]; i++) aj[i] -= cstart; /* resume local col index */
2013 
2014   /* copy over the B part */
2015   ierr  = PetscCalloc1(bi[mb],&cols);CHKERRQ(ierr);
2016   array = Bloc->a;
2017   row   = A->rmap->rstart;
2018   for (i=0; i<bi[mb]; i++) cols[i] = a->garray[bj[i]];
2019   cols_tmp = cols;
2020   for (i=0; i<mb; i++) {
2021     ncol = bi[i+1]-bi[i];
2022     ierr = MatSetValues(B,ncol,cols_tmp,1,&row,array,INSERT_VALUES);CHKERRQ(ierr);
2023     row++;
2024     array += ncol; cols_tmp += ncol;
2025   }
2026   ierr = PetscFree(cols);CHKERRQ(ierr);
2027 
2028   ierr = MatAssemblyBegin(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
2029   ierr = MatAssemblyEnd(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
2030   if (reuse == MAT_INITIAL_MATRIX || *matout != A) {
2031     *matout = B;
2032   } else {
2033     ierr = MatHeaderMerge(A,B);CHKERRQ(ierr);
2034   }
2035   PetscFunctionReturn(0);
2036 }
2037 
2038 #undef __FUNCT__
2039 #define __FUNCT__ "MatDiagonalScale_MPIAIJ"
2040 PetscErrorCode MatDiagonalScale_MPIAIJ(Mat mat,Vec ll,Vec rr)
2041 {
2042   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
2043   Mat            a    = aij->A,b = aij->B;
2044   PetscErrorCode ierr;
2045   PetscInt       s1,s2,s3;
2046 
2047   PetscFunctionBegin;
2048   ierr = MatGetLocalSize(mat,&s2,&s3);CHKERRQ(ierr);
2049   if (rr) {
2050     ierr = VecGetLocalSize(rr,&s1);CHKERRQ(ierr);
2051     if (s1!=s3) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_SIZ,"right vector non-conforming local size");
2052     /* Overlap communication with computation. */
2053     ierr = VecScatterBegin(aij->Mvctx,rr,aij->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
2054   }
2055   if (ll) {
2056     ierr = VecGetLocalSize(ll,&s1);CHKERRQ(ierr);
2057     if (s1!=s2) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_SIZ,"left vector non-conforming local size");
2058     ierr = (*b->ops->diagonalscale)(b,ll,0);CHKERRQ(ierr);
2059   }
2060   /* scale  the diagonal block */
2061   ierr = (*a->ops->diagonalscale)(a,ll,rr);CHKERRQ(ierr);
2062 
2063   if (rr) {
2064     /* Do a scatter end and then right scale the off-diagonal block */
2065     ierr = VecScatterEnd(aij->Mvctx,rr,aij->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
2066     ierr = (*b->ops->diagonalscale)(b,0,aij->lvec);CHKERRQ(ierr);
2067   }
2068   PetscFunctionReturn(0);
2069 }
2070 
2071 #undef __FUNCT__
2072 #define __FUNCT__ "MatSetUnfactored_MPIAIJ"
2073 PetscErrorCode MatSetUnfactored_MPIAIJ(Mat A)
2074 {
2075   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
2076   PetscErrorCode ierr;
2077 
2078   PetscFunctionBegin;
2079   ierr = MatSetUnfactored(a->A);CHKERRQ(ierr);
2080   PetscFunctionReturn(0);
2081 }
2082 
2083 #undef __FUNCT__
2084 #define __FUNCT__ "MatEqual_MPIAIJ"
2085 PetscErrorCode MatEqual_MPIAIJ(Mat A,Mat B,PetscBool  *flag)
2086 {
2087   Mat_MPIAIJ     *matB = (Mat_MPIAIJ*)B->data,*matA = (Mat_MPIAIJ*)A->data;
2088   Mat            a,b,c,d;
2089   PetscBool      flg;
2090   PetscErrorCode ierr;
2091 
2092   PetscFunctionBegin;
2093   a = matA->A; b = matA->B;
2094   c = matB->A; d = matB->B;
2095 
2096   ierr = MatEqual(a,c,&flg);CHKERRQ(ierr);
2097   if (flg) {
2098     ierr = MatEqual(b,d,&flg);CHKERRQ(ierr);
2099   }
2100   ierr = MPI_Allreduce(&flg,flag,1,MPIU_BOOL,MPI_LAND,PetscObjectComm((PetscObject)A));CHKERRQ(ierr);
2101   PetscFunctionReturn(0);
2102 }
2103 
2104 #undef __FUNCT__
2105 #define __FUNCT__ "MatCopy_MPIAIJ"
2106 PetscErrorCode MatCopy_MPIAIJ(Mat A,Mat B,MatStructure str)
2107 {
2108   PetscErrorCode ierr;
2109   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
2110   Mat_MPIAIJ     *b = (Mat_MPIAIJ*)B->data;
2111 
2112   PetscFunctionBegin;
2113   /* If the two matrices don't have the same copy implementation, they aren't compatible for fast copy. */
2114   if ((str != SAME_NONZERO_PATTERN) || (A->ops->copy != B->ops->copy)) {
2115     /* because of the column compression in the off-processor part of the matrix a->B,
2116        the number of columns in a->B and b->B may be different, hence we cannot call
2117        the MatCopy() directly on the two parts. If need be, we can provide a more
2118        efficient copy than the MatCopy_Basic() by first uncompressing the a->B matrices
2119        then copying the submatrices */
2120     ierr = MatCopy_Basic(A,B,str);CHKERRQ(ierr);
2121   } else {
2122     ierr = MatCopy(a->A,b->A,str);CHKERRQ(ierr);
2123     ierr = MatCopy(a->B,b->B,str);CHKERRQ(ierr);
2124   }
2125   PetscFunctionReturn(0);
2126 }
2127 
2128 #undef __FUNCT__
2129 #define __FUNCT__ "MatSetUp_MPIAIJ"
2130 PetscErrorCode MatSetUp_MPIAIJ(Mat A)
2131 {
2132   PetscErrorCode ierr;
2133 
2134   PetscFunctionBegin;
2135   ierr =  MatMPIAIJSetPreallocation(A,PETSC_DEFAULT,0,PETSC_DEFAULT,0);CHKERRQ(ierr);
2136   PetscFunctionReturn(0);
2137 }
2138 
2139 /*
2140    Computes the number of nonzeros per row needed for preallocation when X and Y
2141    have different nonzero structure.
2142 */
2143 #undef __FUNCT__
2144 #define __FUNCT__ "MatAXPYGetPreallocation_MPIX_private"
2145 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)
2146 {
2147   PetscInt       i,j,k,nzx,nzy;
2148 
2149   PetscFunctionBegin;
2150   /* Set the number of nonzeros in the new matrix */
2151   for (i=0; i<m; i++) {
2152     const PetscInt *xjj = xj+xi[i],*yjj = yj+yi[i];
2153     nzx = xi[i+1] - xi[i];
2154     nzy = yi[i+1] - yi[i];
2155     nnz[i] = 0;
2156     for (j=0,k=0; j<nzx; j++) {                   /* Point in X */
2157       for (; k<nzy && yltog[yjj[k]]<xltog[xjj[j]]; k++) nnz[i]++; /* Catch up to X */
2158       if (k<nzy && yltog[yjj[k]]==xltog[xjj[j]]) k++;             /* Skip duplicate */
2159       nnz[i]++;
2160     }
2161     for (; k<nzy; k++) nnz[i]++;
2162   }
2163   PetscFunctionReturn(0);
2164 }
2165 
2166 /* This is the same as MatAXPYGetPreallocation_SeqAIJ, except that the local-to-global map is provided */
2167 #undef __FUNCT__
2168 #define __FUNCT__ "MatAXPYGetPreallocation_MPIAIJ"
2169 static PetscErrorCode MatAXPYGetPreallocation_MPIAIJ(Mat Y,const PetscInt *yltog,Mat X,const PetscInt *xltog,PetscInt *nnz)
2170 {
2171   PetscErrorCode ierr;
2172   PetscInt       m = Y->rmap->N;
2173   Mat_SeqAIJ     *x = (Mat_SeqAIJ*)X->data;
2174   Mat_SeqAIJ     *y = (Mat_SeqAIJ*)Y->data;
2175 
2176   PetscFunctionBegin;
2177   ierr = MatAXPYGetPreallocation_MPIX_private(m,x->i,x->j,xltog,y->i,y->j,yltog,nnz);CHKERRQ(ierr);
2178   PetscFunctionReturn(0);
2179 }
2180 
2181 #undef __FUNCT__
2182 #define __FUNCT__ "MatAXPY_MPIAIJ"
2183 PetscErrorCode MatAXPY_MPIAIJ(Mat Y,PetscScalar a,Mat X,MatStructure str)
2184 {
2185   PetscErrorCode ierr;
2186   Mat_MPIAIJ     *xx = (Mat_MPIAIJ*)X->data,*yy = (Mat_MPIAIJ*)Y->data;
2187   PetscBLASInt   bnz,one=1;
2188   Mat_SeqAIJ     *x,*y;
2189 
2190   PetscFunctionBegin;
2191   if (str == SAME_NONZERO_PATTERN) {
2192     PetscScalar alpha = a;
2193     x    = (Mat_SeqAIJ*)xx->A->data;
2194     ierr = PetscBLASIntCast(x->nz,&bnz);CHKERRQ(ierr);
2195     y    = (Mat_SeqAIJ*)yy->A->data;
2196     PetscStackCallBLAS("BLASaxpy",BLASaxpy_(&bnz,&alpha,x->a,&one,y->a,&one));
2197     x    = (Mat_SeqAIJ*)xx->B->data;
2198     y    = (Mat_SeqAIJ*)yy->B->data;
2199     ierr = PetscBLASIntCast(x->nz,&bnz);CHKERRQ(ierr);
2200     PetscStackCallBLAS("BLASaxpy",BLASaxpy_(&bnz,&alpha,x->a,&one,y->a,&one));
2201     ierr = PetscObjectStateIncrease((PetscObject)Y);CHKERRQ(ierr);
2202   } else if (str == SUBSET_NONZERO_PATTERN) { /* nonzeros of X is a subset of Y's */
2203     ierr = MatAXPY_Basic(Y,a,X,str);CHKERRQ(ierr);
2204   } else {
2205     Mat      B;
2206     PetscInt *nnz_d,*nnz_o;
2207     ierr = PetscMalloc1(yy->A->rmap->N,&nnz_d);CHKERRQ(ierr);
2208     ierr = PetscMalloc1(yy->B->rmap->N,&nnz_o);CHKERRQ(ierr);
2209     ierr = MatCreate(PetscObjectComm((PetscObject)Y),&B);CHKERRQ(ierr);
2210     ierr = PetscObjectSetName((PetscObject)B,((PetscObject)Y)->name);CHKERRQ(ierr);
2211     ierr = MatSetSizes(B,Y->rmap->n,Y->cmap->n,Y->rmap->N,Y->cmap->N);CHKERRQ(ierr);
2212     ierr = MatSetBlockSizesFromMats(B,Y,Y);CHKERRQ(ierr);
2213     ierr = MatSetType(B,MATMPIAIJ);CHKERRQ(ierr);
2214     ierr = MatAXPYGetPreallocation_SeqAIJ(yy->A,xx->A,nnz_d);CHKERRQ(ierr);
2215     ierr = MatAXPYGetPreallocation_MPIAIJ(yy->B,yy->garray,xx->B,xx->garray,nnz_o);CHKERRQ(ierr);
2216     ierr = MatMPIAIJSetPreallocation(B,0,nnz_d,0,nnz_o);CHKERRQ(ierr);
2217     ierr = MatAXPY_BasicWithPreallocation(B,Y,a,X,str);CHKERRQ(ierr);
2218     ierr = MatHeaderReplace(Y,B);CHKERRQ(ierr);
2219     ierr = PetscFree(nnz_d);CHKERRQ(ierr);
2220     ierr = PetscFree(nnz_o);CHKERRQ(ierr);
2221   }
2222   PetscFunctionReturn(0);
2223 }
2224 
2225 extern PetscErrorCode  MatConjugate_SeqAIJ(Mat);
2226 
2227 #undef __FUNCT__
2228 #define __FUNCT__ "MatConjugate_MPIAIJ"
2229 PetscErrorCode  MatConjugate_MPIAIJ(Mat mat)
2230 {
2231 #if defined(PETSC_USE_COMPLEX)
2232   PetscErrorCode ierr;
2233   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
2234 
2235   PetscFunctionBegin;
2236   ierr = MatConjugate_SeqAIJ(aij->A);CHKERRQ(ierr);
2237   ierr = MatConjugate_SeqAIJ(aij->B);CHKERRQ(ierr);
2238 #else
2239   PetscFunctionBegin;
2240 #endif
2241   PetscFunctionReturn(0);
2242 }
2243 
2244 #undef __FUNCT__
2245 #define __FUNCT__ "MatRealPart_MPIAIJ"
2246 PetscErrorCode MatRealPart_MPIAIJ(Mat A)
2247 {
2248   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
2249   PetscErrorCode ierr;
2250 
2251   PetscFunctionBegin;
2252   ierr = MatRealPart(a->A);CHKERRQ(ierr);
2253   ierr = MatRealPart(a->B);CHKERRQ(ierr);
2254   PetscFunctionReturn(0);
2255 }
2256 
2257 #undef __FUNCT__
2258 #define __FUNCT__ "MatImaginaryPart_MPIAIJ"
2259 PetscErrorCode MatImaginaryPart_MPIAIJ(Mat A)
2260 {
2261   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
2262   PetscErrorCode ierr;
2263 
2264   PetscFunctionBegin;
2265   ierr = MatImaginaryPart(a->A);CHKERRQ(ierr);
2266   ierr = MatImaginaryPart(a->B);CHKERRQ(ierr);
2267   PetscFunctionReturn(0);
2268 }
2269 
2270 #if defined(PETSC_HAVE_PBGL)
2271 
2272 #include <boost/parallel/mpi/bsp_process_group.hpp>
2273 #include <boost/graph/distributed/ilu_default_graph.hpp>
2274 #include <boost/graph/distributed/ilu_0_block.hpp>
2275 #include <boost/graph/distributed/ilu_preconditioner.hpp>
2276 #include <boost/graph/distributed/petsc/interface.hpp>
2277 #include <boost/multi_array.hpp>
2278 #include <boost/parallel/distributed_property_map->hpp>
2279 
2280 #undef __FUNCT__
2281 #define __FUNCT__ "MatILUFactorSymbolic_MPIAIJ"
2282 /*
2283   This uses the parallel ILU factorization of Peter Gottschling <pgottsch@osl.iu.edu>
2284 */
2285 PetscErrorCode MatILUFactorSymbolic_MPIAIJ(Mat fact,Mat A, IS isrow, IS iscol, const MatFactorInfo *info)
2286 {
2287   namespace petsc = boost::distributed::petsc;
2288 
2289   namespace graph_dist = boost::graph::distributed;
2290   using boost::graph::distributed::ilu_default::process_group_type;
2291   using boost::graph::ilu_permuted;
2292 
2293   PetscBool      row_identity, col_identity;
2294   PetscContainer c;
2295   PetscInt       m, n, M, N;
2296   PetscErrorCode ierr;
2297 
2298   PetscFunctionBegin;
2299   if (info->levels != 0) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_SUP,"Only levels = 0 supported for parallel ilu");
2300   ierr = ISIdentity(isrow, &row_identity);CHKERRQ(ierr);
2301   ierr = ISIdentity(iscol, &col_identity);CHKERRQ(ierr);
2302   if (!row_identity || !col_identity) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONG,"Row and column permutations must be identity for parallel ILU");
2303 
2304   process_group_type pg;
2305   typedef graph_dist::ilu_default::ilu_level_graph_type lgraph_type;
2306   lgraph_type  *lgraph_p   = new lgraph_type(petsc::num_global_vertices(A), pg, petsc::matrix_distribution(A, pg));
2307   lgraph_type& level_graph = *lgraph_p;
2308   graph_dist::ilu_default::graph_type&            graph(level_graph.graph);
2309 
2310   petsc::read_matrix(A, graph, get(boost::edge_weight, graph));
2311   ilu_permuted(level_graph);
2312 
2313   /* put together the new matrix */
2314   ierr = MatCreate(PetscObjectComm((PetscObject)A), fact);CHKERRQ(ierr);
2315   ierr = MatGetLocalSize(A, &m, &n);CHKERRQ(ierr);
2316   ierr = MatGetSize(A, &M, &N);CHKERRQ(ierr);
2317   ierr = MatSetSizes(fact, m, n, M, N);CHKERRQ(ierr);
2318   ierr = MatSetBlockSizesFromMats(fact,A,A);CHKERRQ(ierr);
2319   ierr = MatSetType(fact, ((PetscObject)A)->type_name);CHKERRQ(ierr);
2320   ierr = MatAssemblyBegin(fact, MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
2321   ierr = MatAssemblyEnd(fact, MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
2322 
2323   ierr = PetscContainerCreate(PetscObjectComm((PetscObject)A), &c);
2324   ierr = PetscContainerSetPointer(c, lgraph_p);
2325   ierr = PetscObjectCompose((PetscObject) (fact), "graph", (PetscObject) c);
2326   ierr = PetscContainerDestroy(&c);
2327   PetscFunctionReturn(0);
2328 }
2329 
2330 #undef __FUNCT__
2331 #define __FUNCT__ "MatLUFactorNumeric_MPIAIJ"
2332 PetscErrorCode MatLUFactorNumeric_MPIAIJ(Mat B,Mat A, const MatFactorInfo *info)
2333 {
2334   PetscFunctionBegin;
2335   PetscFunctionReturn(0);
2336 }
2337 
2338 #undef __FUNCT__
2339 #define __FUNCT__ "MatSolve_MPIAIJ"
2340 /*
2341   This uses the parallel ILU factorization of Peter Gottschling <pgottsch@osl.iu.edu>
2342 */
2343 PetscErrorCode MatSolve_MPIAIJ(Mat A, Vec b, Vec x)
2344 {
2345   namespace graph_dist = boost::graph::distributed;
2346 
2347   typedef graph_dist::ilu_default::ilu_level_graph_type lgraph_type;
2348   lgraph_type    *lgraph_p;
2349   PetscContainer c;
2350   PetscErrorCode ierr;
2351 
2352   PetscFunctionBegin;
2353   ierr = PetscObjectQuery((PetscObject) A, "graph", (PetscObject*) &c);CHKERRQ(ierr);
2354   ierr = PetscContainerGetPointer(c, (void**) &lgraph_p);CHKERRQ(ierr);
2355   ierr = VecCopy(b, x);CHKERRQ(ierr);
2356 
2357   PetscScalar *array_x;
2358   ierr = VecGetArray(x, &array_x);CHKERRQ(ierr);
2359   PetscInt sx;
2360   ierr = VecGetSize(x, &sx);CHKERRQ(ierr);
2361 
2362   PetscScalar *array_b;
2363   ierr = VecGetArray(b, &array_b);CHKERRQ(ierr);
2364   PetscInt sb;
2365   ierr = VecGetSize(b, &sb);CHKERRQ(ierr);
2366 
2367   lgraph_type& level_graph = *lgraph_p;
2368   graph_dist::ilu_default::graph_type&            graph(level_graph.graph);
2369 
2370   typedef boost::multi_array_ref<PetscScalar, 1> array_ref_type;
2371   array_ref_type                                 ref_b(array_b, boost::extents[num_vertices(graph)]);
2372   array_ref_type                                 ref_x(array_x, boost::extents[num_vertices(graph)]);
2373 
2374   typedef boost::iterator_property_map<array_ref_type::iterator,
2375                                        boost::property_map<graph_dist::ilu_default::graph_type, boost::vertex_index_t>::type>  gvector_type;
2376   gvector_type                                   vector_b(ref_b.begin(), get(boost::vertex_index, graph));
2377   gvector_type                                   vector_x(ref_x.begin(), get(boost::vertex_index, graph));
2378 
2379   ilu_set_solve(*lgraph_p, vector_b, vector_x);
2380   PetscFunctionReturn(0);
2381 }
2382 #endif
2383 
2384 #undef __FUNCT__
2385 #define __FUNCT__ "MatGetRowMaxAbs_MPIAIJ"
2386 PetscErrorCode MatGetRowMaxAbs_MPIAIJ(Mat A, Vec v, PetscInt idx[])
2387 {
2388   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
2389   PetscErrorCode ierr;
2390   PetscInt       i,*idxb = 0;
2391   PetscScalar    *va,*vb;
2392   Vec            vtmp;
2393 
2394   PetscFunctionBegin;
2395   ierr = MatGetRowMaxAbs(a->A,v,idx);CHKERRQ(ierr);
2396   ierr = VecGetArray(v,&va);CHKERRQ(ierr);
2397   if (idx) {
2398     for (i=0; i<A->rmap->n; i++) {
2399       if (PetscAbsScalar(va[i])) idx[i] += A->cmap->rstart;
2400     }
2401   }
2402 
2403   ierr = VecCreateSeq(PETSC_COMM_SELF,A->rmap->n,&vtmp);CHKERRQ(ierr);
2404   if (idx) {
2405     ierr = PetscMalloc1(A->rmap->n,&idxb);CHKERRQ(ierr);
2406   }
2407   ierr = MatGetRowMaxAbs(a->B,vtmp,idxb);CHKERRQ(ierr);
2408   ierr = VecGetArray(vtmp,&vb);CHKERRQ(ierr);
2409 
2410   for (i=0; i<A->rmap->n; i++) {
2411     if (PetscAbsScalar(va[i]) < PetscAbsScalar(vb[i])) {
2412       va[i] = vb[i];
2413       if (idx) idx[i] = a->garray[idxb[i]];
2414     }
2415   }
2416 
2417   ierr = VecRestoreArray(v,&va);CHKERRQ(ierr);
2418   ierr = VecRestoreArray(vtmp,&vb);CHKERRQ(ierr);
2419   ierr = PetscFree(idxb);CHKERRQ(ierr);
2420   ierr = VecDestroy(&vtmp);CHKERRQ(ierr);
2421   PetscFunctionReturn(0);
2422 }
2423 
2424 #undef __FUNCT__
2425 #define __FUNCT__ "MatGetRowMinAbs_MPIAIJ"
2426 PetscErrorCode MatGetRowMinAbs_MPIAIJ(Mat A, Vec v, PetscInt idx[])
2427 {
2428   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
2429   PetscErrorCode ierr;
2430   PetscInt       i,*idxb = 0;
2431   PetscScalar    *va,*vb;
2432   Vec            vtmp;
2433 
2434   PetscFunctionBegin;
2435   ierr = MatGetRowMinAbs(a->A,v,idx);CHKERRQ(ierr);
2436   ierr = VecGetArray(v,&va);CHKERRQ(ierr);
2437   if (idx) {
2438     for (i=0; i<A->cmap->n; i++) {
2439       if (PetscAbsScalar(va[i])) idx[i] += A->cmap->rstart;
2440     }
2441   }
2442 
2443   ierr = VecCreateSeq(PETSC_COMM_SELF,A->rmap->n,&vtmp);CHKERRQ(ierr);
2444   if (idx) {
2445     ierr = PetscMalloc1(A->rmap->n,&idxb);CHKERRQ(ierr);
2446   }
2447   ierr = MatGetRowMinAbs(a->B,vtmp,idxb);CHKERRQ(ierr);
2448   ierr = VecGetArray(vtmp,&vb);CHKERRQ(ierr);
2449 
2450   for (i=0; i<A->rmap->n; i++) {
2451     if (PetscAbsScalar(va[i]) > PetscAbsScalar(vb[i])) {
2452       va[i] = vb[i];
2453       if (idx) idx[i] = a->garray[idxb[i]];
2454     }
2455   }
2456 
2457   ierr = VecRestoreArray(v,&va);CHKERRQ(ierr);
2458   ierr = VecRestoreArray(vtmp,&vb);CHKERRQ(ierr);
2459   ierr = PetscFree(idxb);CHKERRQ(ierr);
2460   ierr = VecDestroy(&vtmp);CHKERRQ(ierr);
2461   PetscFunctionReturn(0);
2462 }
2463 
2464 #undef __FUNCT__
2465 #define __FUNCT__ "MatGetRowMin_MPIAIJ"
2466 PetscErrorCode MatGetRowMin_MPIAIJ(Mat A, Vec v, PetscInt idx[])
2467 {
2468   Mat_MPIAIJ     *mat   = (Mat_MPIAIJ*) A->data;
2469   PetscInt       n      = A->rmap->n;
2470   PetscInt       cstart = A->cmap->rstart;
2471   PetscInt       *cmap  = mat->garray;
2472   PetscInt       *diagIdx, *offdiagIdx;
2473   Vec            diagV, offdiagV;
2474   PetscScalar    *a, *diagA, *offdiagA;
2475   PetscInt       r;
2476   PetscErrorCode ierr;
2477 
2478   PetscFunctionBegin;
2479   ierr = PetscMalloc2(n,&diagIdx,n,&offdiagIdx);CHKERRQ(ierr);
2480   ierr = VecCreateSeq(PetscObjectComm((PetscObject)A), n, &diagV);CHKERRQ(ierr);
2481   ierr = VecCreateSeq(PetscObjectComm((PetscObject)A), n, &offdiagV);CHKERRQ(ierr);
2482   ierr = MatGetRowMin(mat->A, diagV,    diagIdx);CHKERRQ(ierr);
2483   ierr = MatGetRowMin(mat->B, offdiagV, offdiagIdx);CHKERRQ(ierr);
2484   ierr = VecGetArray(v,        &a);CHKERRQ(ierr);
2485   ierr = VecGetArray(diagV,    &diagA);CHKERRQ(ierr);
2486   ierr = VecGetArray(offdiagV, &offdiagA);CHKERRQ(ierr);
2487   for (r = 0; r < n; ++r) {
2488     if (PetscAbsScalar(diagA[r]) <= PetscAbsScalar(offdiagA[r])) {
2489       a[r]   = diagA[r];
2490       idx[r] = cstart + diagIdx[r];
2491     } else {
2492       a[r]   = offdiagA[r];
2493       idx[r] = cmap[offdiagIdx[r]];
2494     }
2495   }
2496   ierr = VecRestoreArray(v,        &a);CHKERRQ(ierr);
2497   ierr = VecRestoreArray(diagV,    &diagA);CHKERRQ(ierr);
2498   ierr = VecRestoreArray(offdiagV, &offdiagA);CHKERRQ(ierr);
2499   ierr = VecDestroy(&diagV);CHKERRQ(ierr);
2500   ierr = VecDestroy(&offdiagV);CHKERRQ(ierr);
2501   ierr = PetscFree2(diagIdx, offdiagIdx);CHKERRQ(ierr);
2502   PetscFunctionReturn(0);
2503 }
2504 
2505 #undef __FUNCT__
2506 #define __FUNCT__ "MatGetRowMax_MPIAIJ"
2507 PetscErrorCode MatGetRowMax_MPIAIJ(Mat A, Vec v, PetscInt idx[])
2508 {
2509   Mat_MPIAIJ     *mat   = (Mat_MPIAIJ*) A->data;
2510   PetscInt       n      = A->rmap->n;
2511   PetscInt       cstart = A->cmap->rstart;
2512   PetscInt       *cmap  = mat->garray;
2513   PetscInt       *diagIdx, *offdiagIdx;
2514   Vec            diagV, offdiagV;
2515   PetscScalar    *a, *diagA, *offdiagA;
2516   PetscInt       r;
2517   PetscErrorCode ierr;
2518 
2519   PetscFunctionBegin;
2520   ierr = PetscMalloc2(n,&diagIdx,n,&offdiagIdx);CHKERRQ(ierr);
2521   ierr = VecCreateSeq(PETSC_COMM_SELF, n, &diagV);CHKERRQ(ierr);
2522   ierr = VecCreateSeq(PETSC_COMM_SELF, n, &offdiagV);CHKERRQ(ierr);
2523   ierr = MatGetRowMax(mat->A, diagV,    diagIdx);CHKERRQ(ierr);
2524   ierr = MatGetRowMax(mat->B, offdiagV, offdiagIdx);CHKERRQ(ierr);
2525   ierr = VecGetArray(v,        &a);CHKERRQ(ierr);
2526   ierr = VecGetArray(diagV,    &diagA);CHKERRQ(ierr);
2527   ierr = VecGetArray(offdiagV, &offdiagA);CHKERRQ(ierr);
2528   for (r = 0; r < n; ++r) {
2529     if (PetscAbsScalar(diagA[r]) >= PetscAbsScalar(offdiagA[r])) {
2530       a[r]   = diagA[r];
2531       idx[r] = cstart + diagIdx[r];
2532     } else {
2533       a[r]   = offdiagA[r];
2534       idx[r] = cmap[offdiagIdx[r]];
2535     }
2536   }
2537   ierr = VecRestoreArray(v,        &a);CHKERRQ(ierr);
2538   ierr = VecRestoreArray(diagV,    &diagA);CHKERRQ(ierr);
2539   ierr = VecRestoreArray(offdiagV, &offdiagA);CHKERRQ(ierr);
2540   ierr = VecDestroy(&diagV);CHKERRQ(ierr);
2541   ierr = VecDestroy(&offdiagV);CHKERRQ(ierr);
2542   ierr = PetscFree2(diagIdx, offdiagIdx);CHKERRQ(ierr);
2543   PetscFunctionReturn(0);
2544 }
2545 
2546 #undef __FUNCT__
2547 #define __FUNCT__ "MatGetSeqNonzeroStructure_MPIAIJ"
2548 PetscErrorCode MatGetSeqNonzeroStructure_MPIAIJ(Mat mat,Mat *newmat)
2549 {
2550   PetscErrorCode ierr;
2551   Mat            *dummy;
2552 
2553   PetscFunctionBegin;
2554   ierr    = MatGetSubMatrix_MPIAIJ_All(mat,MAT_DO_NOT_GET_VALUES,MAT_INITIAL_MATRIX,&dummy);CHKERRQ(ierr);
2555   *newmat = *dummy;
2556   ierr    = PetscFree(dummy);CHKERRQ(ierr);
2557   PetscFunctionReturn(0);
2558 }
2559 
2560 #undef __FUNCT__
2561 #define __FUNCT__ "MatInvertBlockDiagonal_MPIAIJ"
2562 PetscErrorCode  MatInvertBlockDiagonal_MPIAIJ(Mat A,const PetscScalar **values)
2563 {
2564   Mat_MPIAIJ     *a = (Mat_MPIAIJ*) A->data;
2565   PetscErrorCode ierr;
2566 
2567   PetscFunctionBegin;
2568   ierr = MatInvertBlockDiagonal(a->A,values);CHKERRQ(ierr);
2569   PetscFunctionReturn(0);
2570 }
2571 
2572 #undef __FUNCT__
2573 #define __FUNCT__ "MatSetRandom_MPIAIJ"
2574 static PetscErrorCode  MatSetRandom_MPIAIJ(Mat x,PetscRandom rctx)
2575 {
2576   PetscErrorCode ierr;
2577   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)x->data;
2578 
2579   PetscFunctionBegin;
2580   ierr = MatSetRandom(aij->A,rctx);CHKERRQ(ierr);
2581   ierr = MatSetRandom(aij->B,rctx);CHKERRQ(ierr);
2582   ierr = MatAssemblyBegin(x,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
2583   ierr = MatAssemblyEnd(x,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
2584   PetscFunctionReturn(0);
2585 }
2586 
2587 #undef __FUNCT__
2588 #define __FUNCT__ "MatMPIAIJSetUseScalableIncreaseOverlap_MPIAIJ"
2589 PetscErrorCode MatMPIAIJSetUseScalableIncreaseOverlap_MPIAIJ(Mat A,PetscBool sc)
2590 {
2591   PetscFunctionBegin;
2592   if (sc) A->ops->increaseoverlap = MatIncreaseOverlap_MPIAIJ_Scalable;
2593   else A->ops->increaseoverlap    = MatIncreaseOverlap_MPIAIJ;
2594   PetscFunctionReturn(0);
2595 }
2596 
2597 #undef __FUNCT__
2598 #define __FUNCT__ "MatMPIAIJSetUseScalableIncreaseOverlap"
2599 /*@
2600    MatMPIAIJSetUseScalableIncreaseOverlap - Determine if the matrix uses a scalable algorithm to compute the overlap
2601 
2602    Collective on Mat
2603 
2604    Input Parameters:
2605 +    A - the matrix
2606 -    sc - PETSC_TRUE indicates use the scalable algorithm (default is not to use the scalable algorithm)
2607 
2608 @*/
2609 PetscErrorCode MatMPIAIJSetUseScalableIncreaseOverlap(Mat A,PetscBool sc)
2610 {
2611   PetscErrorCode       ierr;
2612 
2613   PetscFunctionBegin;
2614   ierr = PetscTryMethod(A,"MatMPIAIJSetUseScalableIncreaseOverlap_C",(Mat,PetscBool),(A,sc));CHKERRQ(ierr);
2615   PetscFunctionReturn(0);
2616 }
2617 
2618 #undef __FUNCT__
2619 #define __FUNCT__ "MatSetFromOptions_MPIAIJ"
2620 PetscErrorCode MatSetFromOptions_MPIAIJ(PetscOptions *PetscOptionsObject,Mat A)
2621 {
2622   PetscErrorCode       ierr;
2623   PetscBool            sc = PETSC_FALSE,flg;
2624 
2625   PetscFunctionBegin;
2626   ierr = PetscOptionsHead(PetscOptionsObject,"MPIAIJ options");CHKERRQ(ierr);
2627   ierr = PetscObjectOptionsBegin((PetscObject)A);
2628     if (A->ops->increaseoverlap == MatIncreaseOverlap_MPIAIJ_Scalable) sc = PETSC_TRUE;
2629     ierr = PetscOptionsBool("-mat_increase_overlap_scalable","Use a scalable algorithm to compute the overlap","MatIncreaseOverlap",sc,&sc,&flg);CHKERRQ(ierr);
2630     if (flg) {
2631       ierr = MatMPIAIJSetUseScalableIncreaseOverlap(A,sc);CHKERRQ(ierr);
2632     }
2633   ierr = PetscOptionsEnd();CHKERRQ(ierr);
2634   PetscFunctionReturn(0);
2635 }
2636 
2637 /* -------------------------------------------------------------------*/
2638 static struct _MatOps MatOps_Values = {MatSetValues_MPIAIJ,
2639                                        MatGetRow_MPIAIJ,
2640                                        MatRestoreRow_MPIAIJ,
2641                                        MatMult_MPIAIJ,
2642                                 /* 4*/ MatMultAdd_MPIAIJ,
2643                                        MatMultTranspose_MPIAIJ,
2644                                        MatMultTransposeAdd_MPIAIJ,
2645 #if defined(PETSC_HAVE_PBGL)
2646                                        MatSolve_MPIAIJ,
2647 #else
2648                                        0,
2649 #endif
2650                                        0,
2651                                        0,
2652                                 /*10*/ 0,
2653                                        0,
2654                                        0,
2655                                        MatSOR_MPIAIJ,
2656                                        MatTranspose_MPIAIJ,
2657                                 /*15*/ MatGetInfo_MPIAIJ,
2658                                        MatEqual_MPIAIJ,
2659                                        MatGetDiagonal_MPIAIJ,
2660                                        MatDiagonalScale_MPIAIJ,
2661                                        MatNorm_MPIAIJ,
2662                                 /*20*/ MatAssemblyBegin_MPIAIJ,
2663                                        MatAssemblyEnd_MPIAIJ,
2664                                        MatSetOption_MPIAIJ,
2665                                        MatZeroEntries_MPIAIJ,
2666                                 /*24*/ MatZeroRows_MPIAIJ,
2667                                        0,
2668 #if defined(PETSC_HAVE_PBGL)
2669                                        0,
2670 #else
2671                                        0,
2672 #endif
2673                                        0,
2674                                        0,
2675                                 /*29*/ MatSetUp_MPIAIJ,
2676 #if defined(PETSC_HAVE_PBGL)
2677                                        0,
2678 #else
2679                                        0,
2680 #endif
2681                                        0,
2682                                        0,
2683                                        0,
2684                                 /*34*/ MatDuplicate_MPIAIJ,
2685                                        0,
2686                                        0,
2687                                        0,
2688                                        0,
2689                                 /*39*/ MatAXPY_MPIAIJ,
2690                                        MatGetSubMatrices_MPIAIJ,
2691                                        MatIncreaseOverlap_MPIAIJ,
2692                                        MatGetValues_MPIAIJ,
2693                                        MatCopy_MPIAIJ,
2694                                 /*44*/ MatGetRowMax_MPIAIJ,
2695                                        MatScale_MPIAIJ,
2696                                        0,
2697                                        MatDiagonalSet_MPIAIJ,
2698                                        MatZeroRowsColumns_MPIAIJ,
2699                                 /*49*/ MatSetRandom_MPIAIJ,
2700                                        0,
2701                                        0,
2702                                        0,
2703                                        0,
2704                                 /*54*/ MatFDColoringCreate_MPIXAIJ,
2705                                        0,
2706                                        MatSetUnfactored_MPIAIJ,
2707                                        MatPermute_MPIAIJ,
2708                                        0,
2709                                 /*59*/ MatGetSubMatrix_MPIAIJ,
2710                                        MatDestroy_MPIAIJ,
2711                                        MatView_MPIAIJ,
2712                                        0,
2713                                        MatMatMatMult_MPIAIJ_MPIAIJ_MPIAIJ,
2714                                 /*64*/ MatMatMatMultSymbolic_MPIAIJ_MPIAIJ_MPIAIJ,
2715                                        MatMatMatMultNumeric_MPIAIJ_MPIAIJ_MPIAIJ,
2716                                        0,
2717                                        0,
2718                                        0,
2719                                 /*69*/ MatGetRowMaxAbs_MPIAIJ,
2720                                        MatGetRowMinAbs_MPIAIJ,
2721                                        0,
2722                                        MatSetColoring_MPIAIJ,
2723                                        0,
2724                                        MatSetValuesAdifor_MPIAIJ,
2725                                 /*75*/ MatFDColoringApply_AIJ,
2726                                        MatSetFromOptions_MPIAIJ,
2727                                        0,
2728                                        0,
2729                                        MatFindZeroDiagonals_MPIAIJ,
2730                                 /*80*/ 0,
2731                                        0,
2732                                        0,
2733                                 /*83*/ MatLoad_MPIAIJ,
2734                                        0,
2735                                        0,
2736                                        0,
2737                                        0,
2738                                        0,
2739                                 /*89*/ MatMatMult_MPIAIJ_MPIAIJ,
2740                                        MatMatMultSymbolic_MPIAIJ_MPIAIJ,
2741                                        MatMatMultNumeric_MPIAIJ_MPIAIJ,
2742                                        MatPtAP_MPIAIJ_MPIAIJ,
2743                                        MatPtAPSymbolic_MPIAIJ_MPIAIJ,
2744                                 /*94*/ MatPtAPNumeric_MPIAIJ_MPIAIJ,
2745                                        0,
2746                                        0,
2747                                        0,
2748                                        0,
2749                                 /*99*/ 0,
2750                                        0,
2751                                        0,
2752                                        MatConjugate_MPIAIJ,
2753                                        0,
2754                                 /*104*/MatSetValuesRow_MPIAIJ,
2755                                        MatRealPart_MPIAIJ,
2756                                        MatImaginaryPart_MPIAIJ,
2757                                        0,
2758                                        0,
2759                                 /*109*/0,
2760                                        0,
2761                                        MatGetRowMin_MPIAIJ,
2762                                        0,
2763                                        0,
2764                                 /*114*/MatGetSeqNonzeroStructure_MPIAIJ,
2765                                        0,
2766                                        0,
2767                                        0,
2768                                        0,
2769                                 /*119*/0,
2770                                        0,
2771                                        0,
2772                                        0,
2773                                        MatGetMultiProcBlock_MPIAIJ,
2774                                 /*124*/MatFindNonzeroRows_MPIAIJ,
2775                                        MatGetColumnNorms_MPIAIJ,
2776                                        MatInvertBlockDiagonal_MPIAIJ,
2777                                        0,
2778                                        MatGetSubMatricesParallel_MPIAIJ,
2779                                 /*129*/0,
2780                                        MatTransposeMatMult_MPIAIJ_MPIAIJ,
2781                                        MatTransposeMatMultSymbolic_MPIAIJ_MPIAIJ,
2782                                        MatTransposeMatMultNumeric_MPIAIJ_MPIAIJ,
2783                                        0,
2784                                 /*134*/0,
2785                                        0,
2786                                        0,
2787                                        0,
2788                                        0,
2789                                 /*139*/0,
2790                                        0,
2791                                        0,
2792                                        MatFDColoringSetUp_MPIXAIJ,
2793                                        MatFindOffBlockDiagonalEntries_MPIAIJ,
2794                                 /*144*/MatCreateMPIMatConcatenateSeqMat_MPIAIJ
2795 };
2796 
2797 /* ----------------------------------------------------------------------------------------*/
2798 
2799 #undef __FUNCT__
2800 #define __FUNCT__ "MatStoreValues_MPIAIJ"
2801 PetscErrorCode  MatStoreValues_MPIAIJ(Mat mat)
2802 {
2803   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
2804   PetscErrorCode ierr;
2805 
2806   PetscFunctionBegin;
2807   ierr = MatStoreValues(aij->A);CHKERRQ(ierr);
2808   ierr = MatStoreValues(aij->B);CHKERRQ(ierr);
2809   PetscFunctionReturn(0);
2810 }
2811 
2812 #undef __FUNCT__
2813 #define __FUNCT__ "MatRetrieveValues_MPIAIJ"
2814 PetscErrorCode  MatRetrieveValues_MPIAIJ(Mat mat)
2815 {
2816   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
2817   PetscErrorCode ierr;
2818 
2819   PetscFunctionBegin;
2820   ierr = MatRetrieveValues(aij->A);CHKERRQ(ierr);
2821   ierr = MatRetrieveValues(aij->B);CHKERRQ(ierr);
2822   PetscFunctionReturn(0);
2823 }
2824 
2825 #undef __FUNCT__
2826 #define __FUNCT__ "MatMPIAIJSetPreallocation_MPIAIJ"
2827 PetscErrorCode  MatMPIAIJSetPreallocation_MPIAIJ(Mat B,PetscInt d_nz,const PetscInt d_nnz[],PetscInt o_nz,const PetscInt o_nnz[])
2828 {
2829   Mat_MPIAIJ     *b;
2830   PetscErrorCode ierr;
2831 
2832   PetscFunctionBegin;
2833   ierr = PetscLayoutSetUp(B->rmap);CHKERRQ(ierr);
2834   ierr = PetscLayoutSetUp(B->cmap);CHKERRQ(ierr);
2835   b = (Mat_MPIAIJ*)B->data;
2836 
2837   if (!B->preallocated) {
2838     /* Explicitly create 2 MATSEQAIJ matrices. */
2839     ierr = MatCreate(PETSC_COMM_SELF,&b->A);CHKERRQ(ierr);
2840     ierr = MatSetSizes(b->A,B->rmap->n,B->cmap->n,B->rmap->n,B->cmap->n);CHKERRQ(ierr);
2841     ierr = MatSetBlockSizesFromMats(b->A,B,B);CHKERRQ(ierr);
2842     ierr = MatSetType(b->A,MATSEQAIJ);CHKERRQ(ierr);
2843     ierr = PetscLogObjectParent((PetscObject)B,(PetscObject)b->A);CHKERRQ(ierr);
2844     ierr = MatCreate(PETSC_COMM_SELF,&b->B);CHKERRQ(ierr);
2845     ierr = MatSetSizes(b->B,B->rmap->n,B->cmap->N,B->rmap->n,B->cmap->N);CHKERRQ(ierr);
2846     ierr = MatSetBlockSizesFromMats(b->B,B,B);CHKERRQ(ierr);
2847     ierr = MatSetType(b->B,MATSEQAIJ);CHKERRQ(ierr);
2848     ierr = PetscLogObjectParent((PetscObject)B,(PetscObject)b->B);CHKERRQ(ierr);
2849   }
2850 
2851   ierr = MatSeqAIJSetPreallocation(b->A,d_nz,d_nnz);CHKERRQ(ierr);
2852   ierr = MatSeqAIJSetPreallocation(b->B,o_nz,o_nnz);CHKERRQ(ierr);
2853   B->preallocated = PETSC_TRUE;
2854   PetscFunctionReturn(0);
2855 }
2856 
2857 #undef __FUNCT__
2858 #define __FUNCT__ "MatDuplicate_MPIAIJ"
2859 PetscErrorCode MatDuplicate_MPIAIJ(Mat matin,MatDuplicateOption cpvalues,Mat *newmat)
2860 {
2861   Mat            mat;
2862   Mat_MPIAIJ     *a,*oldmat = (Mat_MPIAIJ*)matin->data;
2863   PetscErrorCode ierr;
2864 
2865   PetscFunctionBegin;
2866   *newmat = 0;
2867   ierr    = MatCreate(PetscObjectComm((PetscObject)matin),&mat);CHKERRQ(ierr);
2868   ierr    = MatSetSizes(mat,matin->rmap->n,matin->cmap->n,matin->rmap->N,matin->cmap->N);CHKERRQ(ierr);
2869   ierr    = MatSetBlockSizesFromMats(mat,matin,matin);CHKERRQ(ierr);
2870   ierr    = MatSetType(mat,((PetscObject)matin)->type_name);CHKERRQ(ierr);
2871   ierr    = PetscMemcpy(mat->ops,matin->ops,sizeof(struct _MatOps));CHKERRQ(ierr);
2872   a       = (Mat_MPIAIJ*)mat->data;
2873 
2874   mat->factortype   = matin->factortype;
2875   mat->assembled    = PETSC_TRUE;
2876   mat->insertmode   = NOT_SET_VALUES;
2877   mat->preallocated = PETSC_TRUE;
2878 
2879   a->size         = oldmat->size;
2880   a->rank         = oldmat->rank;
2881   a->donotstash   = oldmat->donotstash;
2882   a->roworiented  = oldmat->roworiented;
2883   a->rowindices   = 0;
2884   a->rowvalues    = 0;
2885   a->getrowactive = PETSC_FALSE;
2886 
2887   ierr = PetscLayoutReference(matin->rmap,&mat->rmap);CHKERRQ(ierr);
2888   ierr = PetscLayoutReference(matin->cmap,&mat->cmap);CHKERRQ(ierr);
2889 
2890   if (oldmat->colmap) {
2891 #if defined(PETSC_USE_CTABLE)
2892     ierr = PetscTableCreateCopy(oldmat->colmap,&a->colmap);CHKERRQ(ierr);
2893 #else
2894     ierr = PetscMalloc1(mat->cmap->N,&a->colmap);CHKERRQ(ierr);
2895     ierr = PetscLogObjectMemory((PetscObject)mat,(mat->cmap->N)*sizeof(PetscInt));CHKERRQ(ierr);
2896     ierr = PetscMemcpy(a->colmap,oldmat->colmap,(mat->cmap->N)*sizeof(PetscInt));CHKERRQ(ierr);
2897 #endif
2898   } else a->colmap = 0;
2899   if (oldmat->garray) {
2900     PetscInt len;
2901     len  = oldmat->B->cmap->n;
2902     ierr = PetscMalloc1(len+1,&a->garray);CHKERRQ(ierr);
2903     ierr = PetscLogObjectMemory((PetscObject)mat,len*sizeof(PetscInt));CHKERRQ(ierr);
2904     if (len) { ierr = PetscMemcpy(a->garray,oldmat->garray,len*sizeof(PetscInt));CHKERRQ(ierr); }
2905   } else a->garray = 0;
2906 
2907   ierr    = VecDuplicate(oldmat->lvec,&a->lvec);CHKERRQ(ierr);
2908   ierr    = PetscLogObjectParent((PetscObject)mat,(PetscObject)a->lvec);CHKERRQ(ierr);
2909   ierr    = VecScatterCopy(oldmat->Mvctx,&a->Mvctx);CHKERRQ(ierr);
2910   ierr    = PetscLogObjectParent((PetscObject)mat,(PetscObject)a->Mvctx);CHKERRQ(ierr);
2911   ierr    = MatDuplicate(oldmat->A,cpvalues,&a->A);CHKERRQ(ierr);
2912   ierr    = PetscLogObjectParent((PetscObject)mat,(PetscObject)a->A);CHKERRQ(ierr);
2913   ierr    = MatDuplicate(oldmat->B,cpvalues,&a->B);CHKERRQ(ierr);
2914   ierr    = PetscLogObjectParent((PetscObject)mat,(PetscObject)a->B);CHKERRQ(ierr);
2915   ierr    = PetscFunctionListDuplicate(((PetscObject)matin)->qlist,&((PetscObject)mat)->qlist);CHKERRQ(ierr);
2916   *newmat = mat;
2917   PetscFunctionReturn(0);
2918 }
2919 
2920 
2921 
2922 #undef __FUNCT__
2923 #define __FUNCT__ "MatLoad_MPIAIJ"
2924 PetscErrorCode MatLoad_MPIAIJ(Mat newMat, PetscViewer viewer)
2925 {
2926   PetscScalar    *vals,*svals;
2927   MPI_Comm       comm;
2928   PetscErrorCode ierr;
2929   PetscMPIInt    rank,size,tag = ((PetscObject)viewer)->tag;
2930   PetscInt       i,nz,j,rstart,rend,mmax,maxnz = 0,grows,gcols;
2931   PetscInt       header[4],*rowlengths = 0,M,N,m,*cols;
2932   PetscInt       *ourlens = NULL,*procsnz = NULL,*offlens = NULL,jj,*mycols,*smycols;
2933   PetscInt       cend,cstart,n,*rowners,sizesset=1;
2934   int            fd;
2935   PetscInt       bs = newMat->rmap->bs;
2936 
2937   PetscFunctionBegin;
2938   /* force binary viewer to load .info file if it has not yet done so */
2939   ierr = PetscViewerSetUp(viewer);CHKERRQ(ierr);
2940   ierr = PetscObjectGetComm((PetscObject)viewer,&comm);CHKERRQ(ierr);
2941   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
2942   ierr = MPI_Comm_rank(comm,&rank);CHKERRQ(ierr);
2943   ierr = PetscViewerBinaryGetDescriptor(viewer,&fd);CHKERRQ(ierr);
2944   if (!rank) {
2945     ierr = PetscBinaryRead(fd,(char*)header,4,PETSC_INT);CHKERRQ(ierr);
2946     if (header[0] != MAT_FILE_CLASSID) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_FILE_UNEXPECTED,"not matrix object");
2947   }
2948 
2949   ierr = PetscOptionsBegin(comm,NULL,"Options for loading MPIAIJ matrix","Mat");CHKERRQ(ierr);
2950   ierr = PetscOptionsInt("-matload_block_size","Set the blocksize used to store the matrix","MatLoad",bs,&bs,NULL);CHKERRQ(ierr);
2951   ierr = PetscOptionsEnd();CHKERRQ(ierr);
2952   if (bs < 0) bs = 1;
2953 
2954   if (newMat->rmap->n < 0 && newMat->rmap->N < 0 && newMat->cmap->n < 0 && newMat->cmap->N < 0) sizesset = 0;
2955 
2956   ierr = MPI_Bcast(header+1,3,MPIU_INT,0,comm);CHKERRQ(ierr);
2957   M    = header[1]; N = header[2];
2958   /* If global rows/cols are set to PETSC_DECIDE, set it to the sizes given in the file */
2959   if (sizesset && newMat->rmap->N < 0) newMat->rmap->N = M;
2960   if (sizesset && newMat->cmap->N < 0) newMat->cmap->N = N;
2961 
2962   /* If global sizes are set, check if they are consistent with that given in the file */
2963   if (sizesset) {
2964     ierr = MatGetSize(newMat,&grows,&gcols);CHKERRQ(ierr);
2965   }
2966   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);
2967   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);
2968 
2969   /* determine ownership of all (block) rows */
2970   if (M%bs) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_FILE_UNEXPECTED, "Inconsistent # of rows (%d) and block size (%d)",M,bs);
2971   if (newMat->rmap->n < 0) m = bs*((M/bs)/size + (((M/bs) % size) > rank));    /* PETSC_DECIDE */
2972   else m = newMat->rmap->n; /* Set by user */
2973 
2974   ierr = PetscMalloc1(size+1,&rowners);CHKERRQ(ierr);
2975   ierr = MPI_Allgather(&m,1,MPIU_INT,rowners+1,1,MPIU_INT,comm);CHKERRQ(ierr);
2976 
2977   /* First process needs enough room for process with most rows */
2978   if (!rank) {
2979     mmax = rowners[1];
2980     for (i=2; i<=size; i++) {
2981       mmax = PetscMax(mmax, rowners[i]);
2982     }
2983   } else mmax = -1;             /* unused, but compilers complain */
2984 
2985   rowners[0] = 0;
2986   for (i=2; i<=size; i++) {
2987     rowners[i] += rowners[i-1];
2988   }
2989   rstart = rowners[rank];
2990   rend   = rowners[rank+1];
2991 
2992   /* distribute row lengths to all processors */
2993   ierr = PetscMalloc2(m,&ourlens,m,&offlens);CHKERRQ(ierr);
2994   if (!rank) {
2995     ierr = PetscBinaryRead(fd,ourlens,m,PETSC_INT);CHKERRQ(ierr);
2996     ierr = PetscMalloc1(mmax,&rowlengths);CHKERRQ(ierr);
2997     ierr = PetscCalloc1(size,&procsnz);CHKERRQ(ierr);
2998     for (j=0; j<m; j++) {
2999       procsnz[0] += ourlens[j];
3000     }
3001     for (i=1; i<size; i++) {
3002       ierr = PetscBinaryRead(fd,rowlengths,rowners[i+1]-rowners[i],PETSC_INT);CHKERRQ(ierr);
3003       /* calculate the number of nonzeros on each processor */
3004       for (j=0; j<rowners[i+1]-rowners[i]; j++) {
3005         procsnz[i] += rowlengths[j];
3006       }
3007       ierr = MPIULong_Send(rowlengths,rowners[i+1]-rowners[i],MPIU_INT,i,tag,comm);CHKERRQ(ierr);
3008     }
3009     ierr = PetscFree(rowlengths);CHKERRQ(ierr);
3010   } else {
3011     ierr = MPIULong_Recv(ourlens,m,MPIU_INT,0,tag,comm);CHKERRQ(ierr);
3012   }
3013 
3014   if (!rank) {
3015     /* determine max buffer needed and allocate it */
3016     maxnz = 0;
3017     for (i=0; i<size; i++) {
3018       maxnz = PetscMax(maxnz,procsnz[i]);
3019     }
3020     ierr = PetscMalloc1(maxnz,&cols);CHKERRQ(ierr);
3021 
3022     /* read in my part of the matrix column indices  */
3023     nz   = procsnz[0];
3024     ierr = PetscMalloc1(nz,&mycols);CHKERRQ(ierr);
3025     ierr = PetscBinaryRead(fd,mycols,nz,PETSC_INT);CHKERRQ(ierr);
3026 
3027     /* read in every one elses and ship off */
3028     for (i=1; i<size; i++) {
3029       nz   = procsnz[i];
3030       ierr = PetscBinaryRead(fd,cols,nz,PETSC_INT);CHKERRQ(ierr);
3031       ierr = MPIULong_Send(cols,nz,MPIU_INT,i,tag,comm);CHKERRQ(ierr);
3032     }
3033     ierr = PetscFree(cols);CHKERRQ(ierr);
3034   } else {
3035     /* determine buffer space needed for message */
3036     nz = 0;
3037     for (i=0; i<m; i++) {
3038       nz += ourlens[i];
3039     }
3040     ierr = PetscMalloc1(nz,&mycols);CHKERRQ(ierr);
3041 
3042     /* receive message of column indices*/
3043     ierr = MPIULong_Recv(mycols,nz,MPIU_INT,0,tag,comm);CHKERRQ(ierr);
3044   }
3045 
3046   /* determine column ownership if matrix is not square */
3047   if (N != M) {
3048     if (newMat->cmap->n < 0) n = N/size + ((N % size) > rank);
3049     else n = newMat->cmap->n;
3050     ierr   = MPI_Scan(&n,&cend,1,MPIU_INT,MPI_SUM,comm);CHKERRQ(ierr);
3051     cstart = cend - n;
3052   } else {
3053     cstart = rstart;
3054     cend   = rend;
3055     n      = cend - cstart;
3056   }
3057 
3058   /* loop over local rows, determining number of off diagonal entries */
3059   ierr = PetscMemzero(offlens,m*sizeof(PetscInt));CHKERRQ(ierr);
3060   jj   = 0;
3061   for (i=0; i<m; i++) {
3062     for (j=0; j<ourlens[i]; j++) {
3063       if (mycols[jj] < cstart || mycols[jj] >= cend) offlens[i]++;
3064       jj++;
3065     }
3066   }
3067 
3068   for (i=0; i<m; i++) {
3069     ourlens[i] -= offlens[i];
3070   }
3071   if (!sizesset) {
3072     ierr = MatSetSizes(newMat,m,n,M,N);CHKERRQ(ierr);
3073   }
3074 
3075   if (bs > 1) {ierr = MatSetBlockSize(newMat,bs);CHKERRQ(ierr);}
3076 
3077   ierr = MatMPIAIJSetPreallocation(newMat,0,ourlens,0,offlens);CHKERRQ(ierr);
3078 
3079   for (i=0; i<m; i++) {
3080     ourlens[i] += offlens[i];
3081   }
3082 
3083   if (!rank) {
3084     ierr = PetscMalloc1(maxnz+1,&vals);CHKERRQ(ierr);
3085 
3086     /* read in my part of the matrix numerical values  */
3087     nz   = procsnz[0];
3088     ierr = PetscBinaryRead(fd,vals,nz,PETSC_SCALAR);CHKERRQ(ierr);
3089 
3090     /* insert into matrix */
3091     jj      = rstart;
3092     smycols = mycols;
3093     svals   = vals;
3094     for (i=0; i<m; i++) {
3095       ierr     = MatSetValues_MPIAIJ(newMat,1,&jj,ourlens[i],smycols,svals,INSERT_VALUES);CHKERRQ(ierr);
3096       smycols += ourlens[i];
3097       svals   += ourlens[i];
3098       jj++;
3099     }
3100 
3101     /* read in other processors and ship out */
3102     for (i=1; i<size; i++) {
3103       nz   = procsnz[i];
3104       ierr = PetscBinaryRead(fd,vals,nz,PETSC_SCALAR);CHKERRQ(ierr);
3105       ierr = MPIULong_Send(vals,nz,MPIU_SCALAR,i,((PetscObject)newMat)->tag,comm);CHKERRQ(ierr);
3106     }
3107     ierr = PetscFree(procsnz);CHKERRQ(ierr);
3108   } else {
3109     /* receive numeric values */
3110     ierr = PetscMalloc1(nz+1,&vals);CHKERRQ(ierr);
3111 
3112     /* receive message of values*/
3113     ierr = MPIULong_Recv(vals,nz,MPIU_SCALAR,0,((PetscObject)newMat)->tag,comm);CHKERRQ(ierr);
3114 
3115     /* insert into matrix */
3116     jj      = rstart;
3117     smycols = mycols;
3118     svals   = vals;
3119     for (i=0; i<m; i++) {
3120       ierr     = MatSetValues_MPIAIJ(newMat,1,&jj,ourlens[i],smycols,svals,INSERT_VALUES);CHKERRQ(ierr);
3121       smycols += ourlens[i];
3122       svals   += ourlens[i];
3123       jj++;
3124     }
3125   }
3126   ierr = PetscFree2(ourlens,offlens);CHKERRQ(ierr);
3127   ierr = PetscFree(vals);CHKERRQ(ierr);
3128   ierr = PetscFree(mycols);CHKERRQ(ierr);
3129   ierr = PetscFree(rowners);CHKERRQ(ierr);
3130   ierr = MatAssemblyBegin(newMat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
3131   ierr = MatAssemblyEnd(newMat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
3132   PetscFunctionReturn(0);
3133 }
3134 
3135 #undef __FUNCT__
3136 #define __FUNCT__ "MatGetSubMatrix_MPIAIJ"
3137 PetscErrorCode MatGetSubMatrix_MPIAIJ(Mat mat,IS isrow,IS iscol,MatReuse call,Mat *newmat)
3138 {
3139   PetscErrorCode ierr;
3140   IS             iscol_local;
3141   PetscInt       csize;
3142 
3143   PetscFunctionBegin;
3144   ierr = ISGetLocalSize(iscol,&csize);CHKERRQ(ierr);
3145   if (call == MAT_REUSE_MATRIX) {
3146     ierr = PetscObjectQuery((PetscObject)*newmat,"ISAllGather",(PetscObject*)&iscol_local);CHKERRQ(ierr);
3147     if (!iscol_local) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"Submatrix passed in was not used before, cannot reuse");
3148   } else {
3149     PetscInt cbs;
3150     ierr = ISGetBlockSize(iscol,&cbs);CHKERRQ(ierr);
3151     ierr = ISAllGather(iscol,&iscol_local);CHKERRQ(ierr);
3152     ierr = ISSetBlockSize(iscol_local,cbs);CHKERRQ(ierr);
3153   }
3154   ierr = MatGetSubMatrix_MPIAIJ_Private(mat,isrow,iscol_local,csize,call,newmat);CHKERRQ(ierr);
3155   if (call == MAT_INITIAL_MATRIX) {
3156     ierr = PetscObjectCompose((PetscObject)*newmat,"ISAllGather",(PetscObject)iscol_local);CHKERRQ(ierr);
3157     ierr = ISDestroy(&iscol_local);CHKERRQ(ierr);
3158   }
3159   PetscFunctionReturn(0);
3160 }
3161 
3162 extern PetscErrorCode MatGetSubMatrices_MPIAIJ_Local(Mat,PetscInt,const IS[],const IS[],MatReuse,PetscBool*,Mat*);
3163 #undef __FUNCT__
3164 #define __FUNCT__ "MatGetSubMatrix_MPIAIJ_Private"
3165 /*
3166     Not great since it makes two copies of the submatrix, first an SeqAIJ
3167   in local and then by concatenating the local matrices the end result.
3168   Writing it directly would be much like MatGetSubMatrices_MPIAIJ()
3169 
3170   Note: This requires a sequential iscol with all indices.
3171 */
3172 PetscErrorCode MatGetSubMatrix_MPIAIJ_Private(Mat mat,IS isrow,IS iscol,PetscInt csize,MatReuse call,Mat *newmat)
3173 {
3174   PetscErrorCode ierr;
3175   PetscMPIInt    rank,size;
3176   PetscInt       i,m,n,rstart,row,rend,nz,*cwork,j,bs,cbs;
3177   PetscInt       *ii,*jj,nlocal,*dlens,*olens,dlen,olen,jend,mglobal,ncol;
3178   PetscBool      allcolumns, colflag;
3179   Mat            M,Mreuse;
3180   MatScalar      *vwork,*aa;
3181   MPI_Comm       comm;
3182   Mat_SeqAIJ     *aij;
3183 
3184   PetscFunctionBegin;
3185   ierr = PetscObjectGetComm((PetscObject)mat,&comm);CHKERRQ(ierr);
3186   ierr = MPI_Comm_rank(comm,&rank);CHKERRQ(ierr);
3187   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
3188 
3189   ierr = ISIdentity(iscol,&colflag);CHKERRQ(ierr);
3190   ierr = ISGetLocalSize(iscol,&ncol);CHKERRQ(ierr);
3191   if (colflag && ncol == mat->cmap->N) {
3192     allcolumns = PETSC_TRUE;
3193   } else {
3194     allcolumns = PETSC_FALSE;
3195   }
3196   if (call ==  MAT_REUSE_MATRIX) {
3197     ierr = PetscObjectQuery((PetscObject)*newmat,"SubMatrix",(PetscObject*)&Mreuse);CHKERRQ(ierr);
3198     if (!Mreuse) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"Submatrix passed in was not used before, cannot reuse");
3199     ierr = MatGetSubMatrices_MPIAIJ_Local(mat,1,&isrow,&iscol,MAT_REUSE_MATRIX,&allcolumns,&Mreuse);CHKERRQ(ierr);
3200   } else {
3201     ierr = MatGetSubMatrices_MPIAIJ_Local(mat,1,&isrow,&iscol,MAT_INITIAL_MATRIX,&allcolumns,&Mreuse);CHKERRQ(ierr);
3202   }
3203 
3204   /*
3205       m - number of local rows
3206       n - number of columns (same on all processors)
3207       rstart - first row in new global matrix generated
3208   */
3209   ierr = MatGetSize(Mreuse,&m,&n);CHKERRQ(ierr);
3210   ierr = MatGetBlockSizes(Mreuse,&bs,&cbs);CHKERRQ(ierr);
3211   if (call == MAT_INITIAL_MATRIX) {
3212     aij = (Mat_SeqAIJ*)(Mreuse)->data;
3213     ii  = aij->i;
3214     jj  = aij->j;
3215 
3216     /*
3217         Determine the number of non-zeros in the diagonal and off-diagonal
3218         portions of the matrix in order to do correct preallocation
3219     */
3220 
3221     /* first get start and end of "diagonal" columns */
3222     if (csize == PETSC_DECIDE) {
3223       ierr = ISGetSize(isrow,&mglobal);CHKERRQ(ierr);
3224       if (mglobal == n) { /* square matrix */
3225         nlocal = m;
3226       } else {
3227         nlocal = n/size + ((n % size) > rank);
3228       }
3229     } else {
3230       nlocal = csize;
3231     }
3232     ierr   = MPI_Scan(&nlocal,&rend,1,MPIU_INT,MPI_SUM,comm);CHKERRQ(ierr);
3233     rstart = rend - nlocal;
3234     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);
3235 
3236     /* next, compute all the lengths */
3237     ierr  = PetscMalloc1(2*m+1,&dlens);CHKERRQ(ierr);
3238     olens = dlens + m;
3239     for (i=0; i<m; i++) {
3240       jend = ii[i+1] - ii[i];
3241       olen = 0;
3242       dlen = 0;
3243       for (j=0; j<jend; j++) {
3244         if (*jj < rstart || *jj >= rend) olen++;
3245         else dlen++;
3246         jj++;
3247       }
3248       olens[i] = olen;
3249       dlens[i] = dlen;
3250     }
3251     ierr = MatCreate(comm,&M);CHKERRQ(ierr);
3252     ierr = MatSetSizes(M,m,nlocal,PETSC_DECIDE,n);CHKERRQ(ierr);
3253     ierr = MatSetBlockSizes(M,bs,cbs);CHKERRQ(ierr);
3254     ierr = MatSetType(M,((PetscObject)mat)->type_name);CHKERRQ(ierr);
3255     ierr = MatMPIAIJSetPreallocation(M,0,dlens,0,olens);CHKERRQ(ierr);
3256     ierr = PetscFree(dlens);CHKERRQ(ierr);
3257   } else {
3258     PetscInt ml,nl;
3259 
3260     M    = *newmat;
3261     ierr = MatGetLocalSize(M,&ml,&nl);CHKERRQ(ierr);
3262     if (ml != m) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_SIZ,"Previous matrix must be same size/layout as request");
3263     ierr = MatZeroEntries(M);CHKERRQ(ierr);
3264     /*
3265          The next two lines are needed so we may call MatSetValues_MPIAIJ() below directly,
3266        rather than the slower MatSetValues().
3267     */
3268     M->was_assembled = PETSC_TRUE;
3269     M->assembled     = PETSC_FALSE;
3270   }
3271   ierr = MatGetOwnershipRange(M,&rstart,&rend);CHKERRQ(ierr);
3272   aij  = (Mat_SeqAIJ*)(Mreuse)->data;
3273   ii   = aij->i;
3274   jj   = aij->j;
3275   aa   = aij->a;
3276   for (i=0; i<m; i++) {
3277     row   = rstart + i;
3278     nz    = ii[i+1] - ii[i];
3279     cwork = jj;     jj += nz;
3280     vwork = aa;     aa += nz;
3281     ierr  = MatSetValues_MPIAIJ(M,1,&row,nz,cwork,vwork,INSERT_VALUES);CHKERRQ(ierr);
3282   }
3283 
3284   ierr    = MatAssemblyBegin(M,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
3285   ierr    = MatAssemblyEnd(M,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
3286   *newmat = M;
3287 
3288   /* save submatrix used in processor for next request */
3289   if (call ==  MAT_INITIAL_MATRIX) {
3290     ierr = PetscObjectCompose((PetscObject)M,"SubMatrix",(PetscObject)Mreuse);CHKERRQ(ierr);
3291     ierr = MatDestroy(&Mreuse);CHKERRQ(ierr);
3292   }
3293   PetscFunctionReturn(0);
3294 }
3295 
3296 #undef __FUNCT__
3297 #define __FUNCT__ "MatMPIAIJSetPreallocationCSR_MPIAIJ"
3298 PetscErrorCode  MatMPIAIJSetPreallocationCSR_MPIAIJ(Mat B,const PetscInt Ii[],const PetscInt J[],const PetscScalar v[])
3299 {
3300   PetscInt       m,cstart, cend,j,nnz,i,d;
3301   PetscInt       *d_nnz,*o_nnz,nnz_max = 0,rstart,ii;
3302   const PetscInt *JJ;
3303   PetscScalar    *values;
3304   PetscErrorCode ierr;
3305 
3306   PetscFunctionBegin;
3307   if (Ii[0]) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Ii[0] must be 0 it is %D",Ii[0]);
3308 
3309   ierr   = PetscLayoutSetUp(B->rmap);CHKERRQ(ierr);
3310   ierr   = PetscLayoutSetUp(B->cmap);CHKERRQ(ierr);
3311   m      = B->rmap->n;
3312   cstart = B->cmap->rstart;
3313   cend   = B->cmap->rend;
3314   rstart = B->rmap->rstart;
3315 
3316   ierr = PetscMalloc2(m,&d_nnz,m,&o_nnz);CHKERRQ(ierr);
3317 
3318 #if defined(PETSC_USE_DEBUGGING)
3319   for (i=0; i<m; i++) {
3320     nnz = Ii[i+1]- Ii[i];
3321     JJ  = J + Ii[i];
3322     if (nnz < 0) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Local row %D has a negative %D number of columns",i,nnz);
3323     if (nnz && (JJ[0] < 0)) SETERRRQ1(PETSC_ERR_ARG_WRONGSTATE,"Row %D starts with negative column index",i,j);
3324     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);
3325   }
3326 #endif
3327 
3328   for (i=0; i<m; i++) {
3329     nnz     = Ii[i+1]- Ii[i];
3330     JJ      = J + Ii[i];
3331     nnz_max = PetscMax(nnz_max,nnz);
3332     d       = 0;
3333     for (j=0; j<nnz; j++) {
3334       if (cstart <= JJ[j] && JJ[j] < cend) d++;
3335     }
3336     d_nnz[i] = d;
3337     o_nnz[i] = nnz - d;
3338   }
3339   ierr = MatMPIAIJSetPreallocation(B,0,d_nnz,0,o_nnz);CHKERRQ(ierr);
3340   ierr = PetscFree2(d_nnz,o_nnz);CHKERRQ(ierr);
3341 
3342   if (v) values = (PetscScalar*)v;
3343   else {
3344     ierr = PetscCalloc1(nnz_max+1,&values);CHKERRQ(ierr);
3345   }
3346 
3347   for (i=0; i<m; i++) {
3348     ii   = i + rstart;
3349     nnz  = Ii[i+1]- Ii[i];
3350     ierr = MatSetValues_MPIAIJ(B,1,&ii,nnz,J+Ii[i],values+(v ? Ii[i] : 0),INSERT_VALUES);CHKERRQ(ierr);
3351   }
3352   ierr = MatAssemblyBegin(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
3353   ierr = MatAssemblyEnd(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
3354 
3355   if (!v) {
3356     ierr = PetscFree(values);CHKERRQ(ierr);
3357   }
3358   ierr = MatSetOption(B,MAT_NEW_NONZERO_LOCATION_ERR,PETSC_TRUE);CHKERRQ(ierr);
3359   PetscFunctionReturn(0);
3360 }
3361 
3362 #undef __FUNCT__
3363 #define __FUNCT__ "MatMPIAIJSetPreallocationCSR"
3364 /*@
3365    MatMPIAIJSetPreallocationCSR - Allocates memory for a sparse parallel matrix in AIJ format
3366    (the default parallel PETSc format).
3367 
3368    Collective on MPI_Comm
3369 
3370    Input Parameters:
3371 +  B - the matrix
3372 .  i - the indices into j for the start of each local row (starts with zero)
3373 .  j - the column indices for each local row (starts with zero)
3374 -  v - optional values in the matrix
3375 
3376    Level: developer
3377 
3378    Notes:
3379        The i, j, and a arrays ARE copied by this routine into the internal format used by PETSc;
3380      thus you CANNOT change the matrix entries by changing the values of a[] after you have
3381      called this routine. Use MatCreateMPIAIJWithSplitArrays() to avoid needing to copy the arrays.
3382 
3383        The i and j indices are 0 based, and i indices are indices corresponding to the local j array.
3384 
3385        The format which is used for the sparse matrix input, is equivalent to a
3386     row-major ordering.. i.e for the following matrix, the input data expected is
3387     as shown:
3388 
3389         1 0 0
3390         2 0 3     P0
3391        -------
3392         4 5 6     P1
3393 
3394      Process0 [P0]: rows_owned=[0,1]
3395         i =  {0,1,3}  [size = nrow+1  = 2+1]
3396         j =  {0,0,2}  [size = nz = 6]
3397         v =  {1,2,3}  [size = nz = 6]
3398 
3399      Process1 [P1]: rows_owned=[2]
3400         i =  {0,3}    [size = nrow+1  = 1+1]
3401         j =  {0,1,2}  [size = nz = 6]
3402         v =  {4,5,6}  [size = nz = 6]
3403 
3404 .keywords: matrix, aij, compressed row, sparse, parallel
3405 
3406 .seealso: MatCreate(), MatCreateSeqAIJ(), MatSetValues(), MatMPIAIJSetPreallocation(), MatCreateAIJ(), MPIAIJ,
3407           MatCreateSeqAIJWithArrays(), MatCreateMPIAIJWithSplitArrays()
3408 @*/
3409 PetscErrorCode  MatMPIAIJSetPreallocationCSR(Mat B,const PetscInt i[],const PetscInt j[], const PetscScalar v[])
3410 {
3411   PetscErrorCode ierr;
3412 
3413   PetscFunctionBegin;
3414   ierr = PetscTryMethod(B,"MatMPIAIJSetPreallocationCSR_C",(Mat,const PetscInt[],const PetscInt[],const PetscScalar[]),(B,i,j,v));CHKERRQ(ierr);
3415   PetscFunctionReturn(0);
3416 }
3417 
3418 #undef __FUNCT__
3419 #define __FUNCT__ "MatMPIAIJSetPreallocation"
3420 /*@C
3421    MatMPIAIJSetPreallocation - Preallocates memory for a sparse parallel matrix in AIJ format
3422    (the default parallel PETSc format).  For good matrix assembly performance
3423    the user should preallocate the matrix storage by setting the parameters
3424    d_nz (or d_nnz) and o_nz (or o_nnz).  By setting these parameters accurately,
3425    performance can be increased by more than a factor of 50.
3426 
3427    Collective on MPI_Comm
3428 
3429    Input Parameters:
3430 +  B - the matrix
3431 .  d_nz  - number of nonzeros per row in DIAGONAL portion of local submatrix
3432            (same value is used for all local rows)
3433 .  d_nnz - array containing the number of nonzeros in the various rows of the
3434            DIAGONAL portion of the local submatrix (possibly different for each row)
3435            or NULL, if d_nz is used to specify the nonzero structure.
3436            The size of this array is equal to the number of local rows, i.e 'm'.
3437            For matrices that will be factored, you must leave room for (and set)
3438            the diagonal entry even if it is zero.
3439 .  o_nz  - number of nonzeros per row in the OFF-DIAGONAL portion of local
3440            submatrix (same value is used for all local rows).
3441 -  o_nnz - array containing the number of nonzeros in the various rows of the
3442            OFF-DIAGONAL portion of the local submatrix (possibly different for
3443            each row) or NULL, if o_nz is used to specify the nonzero
3444            structure. The size of this array is equal to the number
3445            of local rows, i.e 'm'.
3446 
3447    If the *_nnz parameter is given then the *_nz parameter is ignored
3448 
3449    The AIJ format (also called the Yale sparse matrix format or
3450    compressed row storage (CSR)), is fully compatible with standard Fortran 77
3451    storage.  The stored row and column indices begin with zero.
3452    See Users-Manual: ch_mat for details.
3453 
3454    The parallel matrix is partitioned such that the first m0 rows belong to
3455    process 0, the next m1 rows belong to process 1, the next m2 rows belong
3456    to process 2 etc.. where m0,m1,m2... are the input parameter 'm'.
3457 
3458    The DIAGONAL portion of the local submatrix of a processor can be defined
3459    as the submatrix which is obtained by extraction the part corresponding to
3460    the rows r1-r2 and columns c1-c2 of the global matrix, where r1 is the
3461    first row that belongs to the processor, r2 is the last row belonging to
3462    the this processor, and c1-c2 is range of indices of the local part of a
3463    vector suitable for applying the matrix to.  This is an mxn matrix.  In the
3464    common case of a square matrix, the row and column ranges are the same and
3465    the DIAGONAL part is also square. The remaining portion of the local
3466    submatrix (mxN) constitute the OFF-DIAGONAL portion.
3467 
3468    If o_nnz, d_nnz are specified, then o_nz, and d_nz are ignored.
3469 
3470    You can call MatGetInfo() to get information on how effective the preallocation was;
3471    for example the fields mallocs,nz_allocated,nz_used,nz_unneeded;
3472    You can also run with the option -info and look for messages with the string
3473    malloc in them to see if additional memory allocation was needed.
3474 
3475    Example usage:
3476 
3477    Consider the following 8x8 matrix with 34 non-zero values, that is
3478    assembled across 3 processors. Lets assume that proc0 owns 3 rows,
3479    proc1 owns 3 rows, proc2 owns 2 rows. This division can be shown
3480    as follows:
3481 
3482 .vb
3483             1  2  0  |  0  3  0  |  0  4
3484     Proc0   0  5  6  |  7  0  0  |  8  0
3485             9  0 10  | 11  0  0  | 12  0
3486     -------------------------------------
3487            13  0 14  | 15 16 17  |  0  0
3488     Proc1   0 18  0  | 19 20 21  |  0  0
3489             0  0  0  | 22 23  0  | 24  0
3490     -------------------------------------
3491     Proc2  25 26 27  |  0  0 28  | 29  0
3492            30  0  0  | 31 32 33  |  0 34
3493 .ve
3494 
3495    This can be represented as a collection of submatrices as:
3496 
3497 .vb
3498       A B C
3499       D E F
3500       G H I
3501 .ve
3502 
3503    Where the submatrices A,B,C are owned by proc0, D,E,F are
3504    owned by proc1, G,H,I are owned by proc2.
3505 
3506    The 'm' parameters for proc0,proc1,proc2 are 3,3,2 respectively.
3507    The 'n' parameters for proc0,proc1,proc2 are 3,3,2 respectively.
3508    The 'M','N' parameters are 8,8, and have the same values on all procs.
3509 
3510    The DIAGONAL submatrices corresponding to proc0,proc1,proc2 are
3511    submatrices [A], [E], [I] respectively. The OFF-DIAGONAL submatrices
3512    corresponding to proc0,proc1,proc2 are [BC], [DF], [GH] respectively.
3513    Internally, each processor stores the DIAGONAL part, and the OFF-DIAGONAL
3514    part as SeqAIJ matrices. for eg: proc1 will store [E] as a SeqAIJ
3515    matrix, ans [DF] as another SeqAIJ matrix.
3516 
3517    When d_nz, o_nz parameters are specified, d_nz storage elements are
3518    allocated for every row of the local diagonal submatrix, and o_nz
3519    storage locations are allocated for every row of the OFF-DIAGONAL submat.
3520    One way to choose d_nz and o_nz is to use the max nonzerors per local
3521    rows for each of the local DIAGONAL, and the OFF-DIAGONAL submatrices.
3522    In this case, the values of d_nz,o_nz are:
3523 .vb
3524      proc0 : dnz = 2, o_nz = 2
3525      proc1 : dnz = 3, o_nz = 2
3526      proc2 : dnz = 1, o_nz = 4
3527 .ve
3528    We are allocating m*(d_nz+o_nz) storage locations for every proc. This
3529    translates to 3*(2+2)=12 for proc0, 3*(3+2)=15 for proc1, 2*(1+4)=10
3530    for proc3. i.e we are using 12+15+10=37 storage locations to store
3531    34 values.
3532 
3533    When d_nnz, o_nnz parameters are specified, the storage is specified
3534    for every row, coresponding to both DIAGONAL and OFF-DIAGONAL submatrices.
3535    In the above case the values for d_nnz,o_nnz are:
3536 .vb
3537      proc0: d_nnz = [2,2,2] and o_nnz = [2,2,2]
3538      proc1: d_nnz = [3,3,2] and o_nnz = [2,1,1]
3539      proc2: d_nnz = [1,1]   and o_nnz = [4,4]
3540 .ve
3541    Here the space allocated is sum of all the above values i.e 34, and
3542    hence pre-allocation is perfect.
3543 
3544    Level: intermediate
3545 
3546 .keywords: matrix, aij, compressed row, sparse, parallel
3547 
3548 .seealso: MatCreate(), MatCreateSeqAIJ(), MatSetValues(), MatCreateAIJ(), MatMPIAIJSetPreallocationCSR(),
3549           MPIAIJ, MatGetInfo(), PetscSplitOwnership()
3550 @*/
3551 PetscErrorCode  MatMPIAIJSetPreallocation(Mat B,PetscInt d_nz,const PetscInt d_nnz[],PetscInt o_nz,const PetscInt o_nnz[])
3552 {
3553   PetscErrorCode ierr;
3554 
3555   PetscFunctionBegin;
3556   PetscValidHeaderSpecific(B,MAT_CLASSID,1);
3557   PetscValidType(B,1);
3558   ierr = PetscTryMethod(B,"MatMPIAIJSetPreallocation_C",(Mat,PetscInt,const PetscInt[],PetscInt,const PetscInt[]),(B,d_nz,d_nnz,o_nz,o_nnz));CHKERRQ(ierr);
3559   PetscFunctionReturn(0);
3560 }
3561 
3562 #undef __FUNCT__
3563 #define __FUNCT__ "MatCreateMPIAIJWithArrays"
3564 /*@
3565      MatCreateMPIAIJWithArrays - creates a MPI AIJ matrix using arrays that contain in standard
3566          CSR format the local rows.
3567 
3568    Collective on MPI_Comm
3569 
3570    Input Parameters:
3571 +  comm - MPI communicator
3572 .  m - number of local rows (Cannot be PETSC_DECIDE)
3573 .  n - This value should be the same as the local size used in creating the
3574        x vector for the matrix-vector product y = Ax. (or PETSC_DECIDE to have
3575        calculated if N is given) For square matrices n is almost always m.
3576 .  M - number of global rows (or PETSC_DETERMINE to have calculated if m is given)
3577 .  N - number of global columns (or PETSC_DETERMINE to have calculated if n is given)
3578 .   i - row indices
3579 .   j - column indices
3580 -   a - matrix values
3581 
3582    Output Parameter:
3583 .   mat - the matrix
3584 
3585    Level: intermediate
3586 
3587    Notes:
3588        The i, j, and a arrays ARE copied by this routine into the internal format used by PETSc;
3589      thus you CANNOT change the matrix entries by changing the values of a[] after you have
3590      called this routine. Use MatCreateMPIAIJWithSplitArrays() to avoid needing to copy the arrays.
3591 
3592        The i and j indices are 0 based, and i indices are indices corresponding to the local j array.
3593 
3594        The format which is used for the sparse matrix input, is equivalent to a
3595     row-major ordering.. i.e for the following matrix, the input data expected is
3596     as shown:
3597 
3598         1 0 0
3599         2 0 3     P0
3600        -------
3601         4 5 6     P1
3602 
3603      Process0 [P0]: rows_owned=[0,1]
3604         i =  {0,1,3}  [size = nrow+1  = 2+1]
3605         j =  {0,0,2}  [size = nz = 6]
3606         v =  {1,2,3}  [size = nz = 6]
3607 
3608      Process1 [P1]: rows_owned=[2]
3609         i =  {0,3}    [size = nrow+1  = 1+1]
3610         j =  {0,1,2}  [size = nz = 6]
3611         v =  {4,5,6}  [size = nz = 6]
3612 
3613 .keywords: matrix, aij, compressed row, sparse, parallel
3614 
3615 .seealso: MatCreate(), MatCreateSeqAIJ(), MatSetValues(), MatMPIAIJSetPreallocation(), MatMPIAIJSetPreallocationCSR(),
3616           MPIAIJ, MatCreateAIJ(), MatCreateMPIAIJWithSplitArrays()
3617 @*/
3618 PetscErrorCode  MatCreateMPIAIJWithArrays(MPI_Comm comm,PetscInt m,PetscInt n,PetscInt M,PetscInt N,const PetscInt i[],const PetscInt j[],const PetscScalar a[],Mat *mat)
3619 {
3620   PetscErrorCode ierr;
3621 
3622   PetscFunctionBegin;
3623   if (i[0]) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"i (row indices) must start with 0");
3624   if (m < 0) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"local number of rows (m) cannot be PETSC_DECIDE, or negative");
3625   ierr = MatCreate(comm,mat);CHKERRQ(ierr);
3626   ierr = MatSetSizes(*mat,m,n,M,N);CHKERRQ(ierr);
3627   /* ierr = MatSetBlockSizes(M,bs,cbs);CHKERRQ(ierr); */
3628   ierr = MatSetType(*mat,MATMPIAIJ);CHKERRQ(ierr);
3629   ierr = MatMPIAIJSetPreallocationCSR(*mat,i,j,a);CHKERRQ(ierr);
3630   PetscFunctionReturn(0);
3631 }
3632 
3633 #undef __FUNCT__
3634 #define __FUNCT__ "MatCreateAIJ"
3635 /*@C
3636    MatCreateAIJ - Creates a sparse parallel matrix in AIJ format
3637    (the default parallel PETSc format).  For good matrix assembly performance
3638    the user should preallocate the matrix storage by setting the parameters
3639    d_nz (or d_nnz) and o_nz (or o_nnz).  By setting these parameters accurately,
3640    performance can be increased by more than a factor of 50.
3641 
3642    Collective on MPI_Comm
3643 
3644    Input Parameters:
3645 +  comm - MPI communicator
3646 .  m - number of local rows (or PETSC_DECIDE to have calculated if M is given)
3647            This value should be the same as the local size used in creating the
3648            y vector for the matrix-vector product y = Ax.
3649 .  n - This value should be the same as the local size used in creating the
3650        x vector for the matrix-vector product y = Ax. (or PETSC_DECIDE to have
3651        calculated if N is given) For square matrices n is almost always m.
3652 .  M - number of global rows (or PETSC_DETERMINE to have calculated if m is given)
3653 .  N - number of global columns (or PETSC_DETERMINE to have calculated if n is given)
3654 .  d_nz  - number of nonzeros per row in DIAGONAL portion of local submatrix
3655            (same value is used for all local rows)
3656 .  d_nnz - array containing the number of nonzeros in the various rows of the
3657            DIAGONAL portion of the local submatrix (possibly different for each row)
3658            or NULL, if d_nz is used to specify the nonzero structure.
3659            The size of this array is equal to the number of local rows, i.e 'm'.
3660 .  o_nz  - number of nonzeros per row in the OFF-DIAGONAL portion of local
3661            submatrix (same value is used for all local rows).
3662 -  o_nnz - array containing the number of nonzeros in the various rows of the
3663            OFF-DIAGONAL portion of the local submatrix (possibly different for
3664            each row) or NULL, if o_nz is used to specify the nonzero
3665            structure. The size of this array is equal to the number
3666            of local rows, i.e 'm'.
3667 
3668    Output Parameter:
3669 .  A - the matrix
3670 
3671    It is recommended that one use the MatCreate(), MatSetType() and/or MatSetFromOptions(),
3672    MatXXXXSetPreallocation() paradgm instead of this routine directly.
3673    [MatXXXXSetPreallocation() is, for example, MatSeqAIJSetPreallocation]
3674 
3675    Notes:
3676    If the *_nnz parameter is given then the *_nz parameter is ignored
3677 
3678    m,n,M,N parameters specify the size of the matrix, and its partitioning across
3679    processors, while d_nz,d_nnz,o_nz,o_nnz parameters specify the approximate
3680    storage requirements for this matrix.
3681 
3682    If PETSC_DECIDE or  PETSC_DETERMINE is used for a particular argument on one
3683    processor than it must be used on all processors that share the object for
3684    that argument.
3685 
3686    The user MUST specify either the local or global matrix dimensions
3687    (possibly both).
3688 
3689    The parallel matrix is partitioned across processors such that the
3690    first m0 rows belong to process 0, the next m1 rows belong to
3691    process 1, the next m2 rows belong to process 2 etc.. where
3692    m0,m1,m2,.. are the input parameter 'm'. i.e each processor stores
3693    values corresponding to [m x N] submatrix.
3694 
3695    The columns are logically partitioned with the n0 columns belonging
3696    to 0th partition, the next n1 columns belonging to the next
3697    partition etc.. where n0,n1,n2... are the input parameter 'n'.
3698 
3699    The DIAGONAL portion of the local submatrix on any given processor
3700    is the submatrix corresponding to the rows and columns m,n
3701    corresponding to the given processor. i.e diagonal matrix on
3702    process 0 is [m0 x n0], diagonal matrix on process 1 is [m1 x n1]
3703    etc. The remaining portion of the local submatrix [m x (N-n)]
3704    constitute the OFF-DIAGONAL portion. The example below better
3705    illustrates this concept.
3706 
3707    For a square global matrix we define each processor's diagonal portion
3708    to be its local rows and the corresponding columns (a square submatrix);
3709    each processor's off-diagonal portion encompasses the remainder of the
3710    local matrix (a rectangular submatrix).
3711 
3712    If o_nnz, d_nnz are specified, then o_nz, and d_nz are ignored.
3713 
3714    When calling this routine with a single process communicator, a matrix of
3715    type SEQAIJ is returned.  If a matrix of type MPIAIJ is desired for this
3716    type of communicator, use the construction mechanism:
3717      MatCreate(...,&A); MatSetType(A,MATMPIAIJ); MatSetSizes(A, m,n,M,N); MatMPIAIJSetPreallocation(A,...);
3718 
3719    By default, this format uses inodes (identical nodes) when possible.
3720    We search for consecutive rows with the same nonzero structure, thereby
3721    reusing matrix information to achieve increased efficiency.
3722 
3723    Options Database Keys:
3724 +  -mat_no_inode  - Do not use inodes
3725 .  -mat_inode_limit <limit> - Sets inode limit (max limit=5)
3726 -  -mat_aij_oneindex - Internally use indexing starting at 1
3727         rather than 0.  Note that when calling MatSetValues(),
3728         the user still MUST index entries starting at 0!
3729 
3730 
3731    Example usage:
3732 
3733    Consider the following 8x8 matrix with 34 non-zero values, that is
3734    assembled across 3 processors. Lets assume that proc0 owns 3 rows,
3735    proc1 owns 3 rows, proc2 owns 2 rows. This division can be shown
3736    as follows:
3737 
3738 .vb
3739             1  2  0  |  0  3  0  |  0  4
3740     Proc0   0  5  6  |  7  0  0  |  8  0
3741             9  0 10  | 11  0  0  | 12  0
3742     -------------------------------------
3743            13  0 14  | 15 16 17  |  0  0
3744     Proc1   0 18  0  | 19 20 21  |  0  0
3745             0  0  0  | 22 23  0  | 24  0
3746     -------------------------------------
3747     Proc2  25 26 27  |  0  0 28  | 29  0
3748            30  0  0  | 31 32 33  |  0 34
3749 .ve
3750 
3751    This can be represented as a collection of submatrices as:
3752 
3753 .vb
3754       A B C
3755       D E F
3756       G H I
3757 .ve
3758 
3759    Where the submatrices A,B,C are owned by proc0, D,E,F are
3760    owned by proc1, G,H,I are owned by proc2.
3761 
3762    The 'm' parameters for proc0,proc1,proc2 are 3,3,2 respectively.
3763    The 'n' parameters for proc0,proc1,proc2 are 3,3,2 respectively.
3764    The 'M','N' parameters are 8,8, and have the same values on all procs.
3765 
3766    The DIAGONAL submatrices corresponding to proc0,proc1,proc2 are
3767    submatrices [A], [E], [I] respectively. The OFF-DIAGONAL submatrices
3768    corresponding to proc0,proc1,proc2 are [BC], [DF], [GH] respectively.
3769    Internally, each processor stores the DIAGONAL part, and the OFF-DIAGONAL
3770    part as SeqAIJ matrices. for eg: proc1 will store [E] as a SeqAIJ
3771    matrix, ans [DF] as another SeqAIJ matrix.
3772 
3773    When d_nz, o_nz parameters are specified, d_nz storage elements are
3774    allocated for every row of the local diagonal submatrix, and o_nz
3775    storage locations are allocated for every row of the OFF-DIAGONAL submat.
3776    One way to choose d_nz and o_nz is to use the max nonzerors per local
3777    rows for each of the local DIAGONAL, and the OFF-DIAGONAL submatrices.
3778    In this case, the values of d_nz,o_nz are:
3779 .vb
3780      proc0 : dnz = 2, o_nz = 2
3781      proc1 : dnz = 3, o_nz = 2
3782      proc2 : dnz = 1, o_nz = 4
3783 .ve
3784    We are allocating m*(d_nz+o_nz) storage locations for every proc. This
3785    translates to 3*(2+2)=12 for proc0, 3*(3+2)=15 for proc1, 2*(1+4)=10
3786    for proc3. i.e we are using 12+15+10=37 storage locations to store
3787    34 values.
3788 
3789    When d_nnz, o_nnz parameters are specified, the storage is specified
3790    for every row, coresponding to both DIAGONAL and OFF-DIAGONAL submatrices.
3791    In the above case the values for d_nnz,o_nnz are:
3792 .vb
3793      proc0: d_nnz = [2,2,2] and o_nnz = [2,2,2]
3794      proc1: d_nnz = [3,3,2] and o_nnz = [2,1,1]
3795      proc2: d_nnz = [1,1]   and o_nnz = [4,4]
3796 .ve
3797    Here the space allocated is sum of all the above values i.e 34, and
3798    hence pre-allocation is perfect.
3799 
3800    Level: intermediate
3801 
3802 .keywords: matrix, aij, compressed row, sparse, parallel
3803 
3804 .seealso: MatCreate(), MatCreateSeqAIJ(), MatSetValues(), MatMPIAIJSetPreallocation(), MatMPIAIJSetPreallocationCSR(),
3805           MPIAIJ, MatCreateMPIAIJWithArrays()
3806 @*/
3807 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)
3808 {
3809   PetscErrorCode ierr;
3810   PetscMPIInt    size;
3811 
3812   PetscFunctionBegin;
3813   ierr = MatCreate(comm,A);CHKERRQ(ierr);
3814   ierr = MatSetSizes(*A,m,n,M,N);CHKERRQ(ierr);
3815   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
3816   if (size > 1) {
3817     ierr = MatSetType(*A,MATMPIAIJ);CHKERRQ(ierr);
3818     ierr = MatMPIAIJSetPreallocation(*A,d_nz,d_nnz,o_nz,o_nnz);CHKERRQ(ierr);
3819   } else {
3820     ierr = MatSetType(*A,MATSEQAIJ);CHKERRQ(ierr);
3821     ierr = MatSeqAIJSetPreallocation(*A,d_nz,d_nnz);CHKERRQ(ierr);
3822   }
3823   PetscFunctionReturn(0);
3824 }
3825 
3826 #undef __FUNCT__
3827 #define __FUNCT__ "MatMPIAIJGetSeqAIJ"
3828 PetscErrorCode  MatMPIAIJGetSeqAIJ(Mat A,Mat *Ad,Mat *Ao,const PetscInt *colmap[])
3829 {
3830   Mat_MPIAIJ *a = (Mat_MPIAIJ*)A->data;
3831 
3832   PetscFunctionBegin;
3833   if (Ad)     *Ad     = a->A;
3834   if (Ao)     *Ao     = a->B;
3835   if (colmap) *colmap = a->garray;
3836   PetscFunctionReturn(0);
3837 }
3838 
3839 #undef __FUNCT__
3840 #define __FUNCT__ "MatSetColoring_MPIAIJ"
3841 PetscErrorCode MatSetColoring_MPIAIJ(Mat A,ISColoring coloring)
3842 {
3843   PetscErrorCode ierr;
3844   PetscInt       i;
3845   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
3846 
3847   PetscFunctionBegin;
3848   if (coloring->ctype == IS_COLORING_GLOBAL) {
3849     ISColoringValue *allcolors,*colors;
3850     ISColoring      ocoloring;
3851 
3852     /* set coloring for diagonal portion */
3853     ierr = MatSetColoring_SeqAIJ(a->A,coloring);CHKERRQ(ierr);
3854 
3855     /* set coloring for off-diagonal portion */
3856     ierr = ISAllGatherColors(PetscObjectComm((PetscObject)A),coloring->n,coloring->colors,NULL,&allcolors);CHKERRQ(ierr);
3857     ierr = PetscMalloc1(a->B->cmap->n+1,&colors);CHKERRQ(ierr);
3858     for (i=0; i<a->B->cmap->n; i++) {
3859       colors[i] = allcolors[a->garray[i]];
3860     }
3861     ierr = PetscFree(allcolors);CHKERRQ(ierr);
3862     ierr = ISColoringCreate(MPI_COMM_SELF,coloring->n,a->B->cmap->n,colors,PETSC_OWN_POINTER,&ocoloring);CHKERRQ(ierr);
3863     ierr = MatSetColoring_SeqAIJ(a->B,ocoloring);CHKERRQ(ierr);
3864     ierr = ISColoringDestroy(&ocoloring);CHKERRQ(ierr);
3865   } else if (coloring->ctype == IS_COLORING_GHOSTED) {
3866     ISColoringValue *colors;
3867     PetscInt        *larray;
3868     ISColoring      ocoloring;
3869 
3870     /* set coloring for diagonal portion */
3871     ierr = PetscMalloc1(a->A->cmap->n+1,&larray);CHKERRQ(ierr);
3872     for (i=0; i<a->A->cmap->n; i++) {
3873       larray[i] = i + A->cmap->rstart;
3874     }
3875     ierr = ISGlobalToLocalMappingApply(A->cmap->mapping,IS_GTOLM_MASK,a->A->cmap->n,larray,NULL,larray);CHKERRQ(ierr);
3876     ierr = PetscMalloc1(a->A->cmap->n+1,&colors);CHKERRQ(ierr);
3877     for (i=0; i<a->A->cmap->n; i++) {
3878       colors[i] = coloring->colors[larray[i]];
3879     }
3880     ierr = PetscFree(larray);CHKERRQ(ierr);
3881     ierr = ISColoringCreate(PETSC_COMM_SELF,coloring->n,a->A->cmap->n,colors,PETSC_OWN_POINTER,&ocoloring);CHKERRQ(ierr);
3882     ierr = MatSetColoring_SeqAIJ(a->A,ocoloring);CHKERRQ(ierr);
3883     ierr = ISColoringDestroy(&ocoloring);CHKERRQ(ierr);
3884 
3885     /* set coloring for off-diagonal portion */
3886     ierr = PetscMalloc1(a->B->cmap->n+1,&larray);CHKERRQ(ierr);
3887     ierr = ISGlobalToLocalMappingApply(A->cmap->mapping,IS_GTOLM_MASK,a->B->cmap->n,a->garray,NULL,larray);CHKERRQ(ierr);
3888     ierr = PetscMalloc1(a->B->cmap->n+1,&colors);CHKERRQ(ierr);
3889     for (i=0; i<a->B->cmap->n; i++) {
3890       colors[i] = coloring->colors[larray[i]];
3891     }
3892     ierr = PetscFree(larray);CHKERRQ(ierr);
3893     ierr = ISColoringCreate(MPI_COMM_SELF,coloring->n,a->B->cmap->n,colors,PETSC_OWN_POINTER,&ocoloring);CHKERRQ(ierr);
3894     ierr = MatSetColoring_SeqAIJ(a->B,ocoloring);CHKERRQ(ierr);
3895     ierr = ISColoringDestroy(&ocoloring);CHKERRQ(ierr);
3896   } else SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_SUP,"No support ISColoringType %d",(int)coloring->ctype);
3897   PetscFunctionReturn(0);
3898 }
3899 
3900 #undef __FUNCT__
3901 #define __FUNCT__ "MatSetValuesAdifor_MPIAIJ"
3902 PetscErrorCode MatSetValuesAdifor_MPIAIJ(Mat A,PetscInt nl,void *advalues)
3903 {
3904   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
3905   PetscErrorCode ierr;
3906 
3907   PetscFunctionBegin;
3908   ierr = MatSetValuesAdifor_SeqAIJ(a->A,nl,advalues);CHKERRQ(ierr);
3909   ierr = MatSetValuesAdifor_SeqAIJ(a->B,nl,advalues);CHKERRQ(ierr);
3910   PetscFunctionReturn(0);
3911 }
3912 
3913 #undef __FUNCT__
3914 #define __FUNCT__ "MatCreateMPIMatConcatenateSeqMat_MPIAIJ"
3915 PetscErrorCode MatCreateMPIMatConcatenateSeqMat_MPIAIJ(MPI_Comm comm,Mat inmat,PetscInt n,MatReuse scall,Mat *outmat)
3916 {
3917   PetscErrorCode ierr;
3918   PetscInt       m,N,i,rstart,nnz,Ii;
3919   PetscInt       *indx;
3920   PetscScalar    *values;
3921 
3922   PetscFunctionBegin;
3923   ierr = MatGetSize(inmat,&m,&N);CHKERRQ(ierr);
3924   if (scall == MAT_INITIAL_MATRIX) { /* symbolic phase */
3925     PetscInt       *dnz,*onz,sum,bs,cbs;
3926 
3927     if (n == PETSC_DECIDE) {
3928       ierr = PetscSplitOwnership(comm,&n,&N);CHKERRQ(ierr);
3929     }
3930     /* Check sum(n) = N */
3931     ierr = MPI_Allreduce(&n,&sum,1,MPIU_INT,MPI_SUM,comm);CHKERRQ(ierr);
3932     if (sum != N) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_INCOMP,"Sum of local columns != global columns %d",N);
3933 
3934     ierr    = MPI_Scan(&m, &rstart,1,MPIU_INT,MPI_SUM,comm);CHKERRQ(ierr);
3935     rstart -= m;
3936 
3937     ierr = MatPreallocateInitialize(comm,m,n,dnz,onz);CHKERRQ(ierr);
3938     for (i=0; i<m; i++) {
3939       ierr = MatGetRow_SeqAIJ(inmat,i,&nnz,&indx,NULL);CHKERRQ(ierr);
3940       ierr = MatPreallocateSet(i+rstart,nnz,indx,dnz,onz);CHKERRQ(ierr);
3941       ierr = MatRestoreRow_SeqAIJ(inmat,i,&nnz,&indx,NULL);CHKERRQ(ierr);
3942     }
3943 
3944     ierr = MatCreate(comm,outmat);CHKERRQ(ierr);
3945     ierr = MatSetSizes(*outmat,m,n,PETSC_DETERMINE,PETSC_DETERMINE);CHKERRQ(ierr);
3946     ierr = MatGetBlockSizes(inmat,&bs,&cbs);CHKERRQ(ierr);
3947     ierr = MatSetBlockSizes(*outmat,bs,cbs);CHKERRQ(ierr);
3948     ierr = MatSetType(*outmat,MATMPIAIJ);CHKERRQ(ierr);
3949     ierr = MatMPIAIJSetPreallocation(*outmat,0,dnz,0,onz);CHKERRQ(ierr);
3950     ierr = MatPreallocateFinalize(dnz,onz);CHKERRQ(ierr);
3951   }
3952 
3953   /* numeric phase */
3954   ierr = MatGetOwnershipRange(*outmat,&rstart,NULL);CHKERRQ(ierr);
3955   for (i=0; i<m; i++) {
3956     ierr = MatGetRow_SeqAIJ(inmat,i,&nnz,&indx,&values);CHKERRQ(ierr);
3957     Ii   = i + rstart;
3958     ierr = MatSetValues(*outmat,1,&Ii,nnz,indx,values,INSERT_VALUES);CHKERRQ(ierr);
3959     ierr = MatRestoreRow_SeqAIJ(inmat,i,&nnz,&indx,&values);CHKERRQ(ierr);
3960   }
3961   ierr = MatAssemblyBegin(*outmat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
3962   ierr = MatAssemblyEnd(*outmat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
3963   PetscFunctionReturn(0);
3964 }
3965 
3966 #undef __FUNCT__
3967 #define __FUNCT__ "MatFileSplit"
3968 PetscErrorCode MatFileSplit(Mat A,char *outfile)
3969 {
3970   PetscErrorCode    ierr;
3971   PetscMPIInt       rank;
3972   PetscInt          m,N,i,rstart,nnz;
3973   size_t            len;
3974   const PetscInt    *indx;
3975   PetscViewer       out;
3976   char              *name;
3977   Mat               B;
3978   const PetscScalar *values;
3979 
3980   PetscFunctionBegin;
3981   ierr = MatGetLocalSize(A,&m,0);CHKERRQ(ierr);
3982   ierr = MatGetSize(A,0,&N);CHKERRQ(ierr);
3983   /* Should this be the type of the diagonal block of A? */
3984   ierr = MatCreate(PETSC_COMM_SELF,&B);CHKERRQ(ierr);
3985   ierr = MatSetSizes(B,m,N,m,N);CHKERRQ(ierr);
3986   ierr = MatSetBlockSizesFromMats(B,A,A);CHKERRQ(ierr);
3987   ierr = MatSetType(B,MATSEQAIJ);CHKERRQ(ierr);
3988   ierr = MatSeqAIJSetPreallocation(B,0,NULL);CHKERRQ(ierr);
3989   ierr = MatGetOwnershipRange(A,&rstart,0);CHKERRQ(ierr);
3990   for (i=0; i<m; i++) {
3991     ierr = MatGetRow(A,i+rstart,&nnz,&indx,&values);CHKERRQ(ierr);
3992     ierr = MatSetValues(B,1,&i,nnz,indx,values,INSERT_VALUES);CHKERRQ(ierr);
3993     ierr = MatRestoreRow(A,i+rstart,&nnz,&indx,&values);CHKERRQ(ierr);
3994   }
3995   ierr = MatAssemblyBegin(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
3996   ierr = MatAssemblyEnd(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
3997 
3998   ierr = MPI_Comm_rank(PetscObjectComm((PetscObject)A),&rank);CHKERRQ(ierr);
3999   ierr = PetscStrlen(outfile,&len);CHKERRQ(ierr);
4000   ierr = PetscMalloc1(len+5,&name);CHKERRQ(ierr);
4001   sprintf(name,"%s.%d",outfile,rank);
4002   ierr = PetscViewerBinaryOpen(PETSC_COMM_SELF,name,FILE_MODE_APPEND,&out);CHKERRQ(ierr);
4003   ierr = PetscFree(name);CHKERRQ(ierr);
4004   ierr = MatView(B,out);CHKERRQ(ierr);
4005   ierr = PetscViewerDestroy(&out);CHKERRQ(ierr);
4006   ierr = MatDestroy(&B);CHKERRQ(ierr);
4007   PetscFunctionReturn(0);
4008 }
4009 
4010 extern PetscErrorCode MatDestroy_MPIAIJ(Mat);
4011 #undef __FUNCT__
4012 #define __FUNCT__ "MatDestroy_MPIAIJ_SeqsToMPI"
4013 PetscErrorCode  MatDestroy_MPIAIJ_SeqsToMPI(Mat A)
4014 {
4015   PetscErrorCode      ierr;
4016   Mat_Merge_SeqsToMPI *merge;
4017   PetscContainer      container;
4018 
4019   PetscFunctionBegin;
4020   ierr = PetscObjectQuery((PetscObject)A,"MatMergeSeqsToMPI",(PetscObject*)&container);CHKERRQ(ierr);
4021   if (container) {
4022     ierr = PetscContainerGetPointer(container,(void**)&merge);CHKERRQ(ierr);
4023     ierr = PetscFree(merge->id_r);CHKERRQ(ierr);
4024     ierr = PetscFree(merge->len_s);CHKERRQ(ierr);
4025     ierr = PetscFree(merge->len_r);CHKERRQ(ierr);
4026     ierr = PetscFree(merge->bi);CHKERRQ(ierr);
4027     ierr = PetscFree(merge->bj);CHKERRQ(ierr);
4028     ierr = PetscFree(merge->buf_ri[0]);CHKERRQ(ierr);
4029     ierr = PetscFree(merge->buf_ri);CHKERRQ(ierr);
4030     ierr = PetscFree(merge->buf_rj[0]);CHKERRQ(ierr);
4031     ierr = PetscFree(merge->buf_rj);CHKERRQ(ierr);
4032     ierr = PetscFree(merge->coi);CHKERRQ(ierr);
4033     ierr = PetscFree(merge->coj);CHKERRQ(ierr);
4034     ierr = PetscFree(merge->owners_co);CHKERRQ(ierr);
4035     ierr = PetscLayoutDestroy(&merge->rowmap);CHKERRQ(ierr);
4036     ierr = PetscFree(merge);CHKERRQ(ierr);
4037     ierr = PetscObjectCompose((PetscObject)A,"MatMergeSeqsToMPI",0);CHKERRQ(ierr);
4038   }
4039   ierr = MatDestroy_MPIAIJ(A);CHKERRQ(ierr);
4040   PetscFunctionReturn(0);
4041 }
4042 
4043 #include <../src/mat/utils/freespace.h>
4044 #include <petscbt.h>
4045 
4046 #undef __FUNCT__
4047 #define __FUNCT__ "MatCreateMPIAIJSumSeqAIJNumeric"
4048 PetscErrorCode  MatCreateMPIAIJSumSeqAIJNumeric(Mat seqmat,Mat mpimat)
4049 {
4050   PetscErrorCode      ierr;
4051   MPI_Comm            comm;
4052   Mat_SeqAIJ          *a  =(Mat_SeqAIJ*)seqmat->data;
4053   PetscMPIInt         size,rank,taga,*len_s;
4054   PetscInt            N=mpimat->cmap->N,i,j,*owners,*ai=a->i,*aj;
4055   PetscInt            proc,m;
4056   PetscInt            **buf_ri,**buf_rj;
4057   PetscInt            k,anzi,*bj_i,*bi,*bj,arow,bnzi,nextaj;
4058   PetscInt            nrows,**buf_ri_k,**nextrow,**nextai;
4059   MPI_Request         *s_waits,*r_waits;
4060   MPI_Status          *status;
4061   MatScalar           *aa=a->a;
4062   MatScalar           **abuf_r,*ba_i;
4063   Mat_Merge_SeqsToMPI *merge;
4064   PetscContainer      container;
4065 
4066   PetscFunctionBegin;
4067   ierr = PetscObjectGetComm((PetscObject)mpimat,&comm);CHKERRQ(ierr);
4068   ierr = PetscLogEventBegin(MAT_Seqstompinum,seqmat,0,0,0);CHKERRQ(ierr);
4069 
4070   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
4071   ierr = MPI_Comm_rank(comm,&rank);CHKERRQ(ierr);
4072 
4073   ierr = PetscObjectQuery((PetscObject)mpimat,"MatMergeSeqsToMPI",(PetscObject*)&container);CHKERRQ(ierr);
4074   ierr = PetscContainerGetPointer(container,(void**)&merge);CHKERRQ(ierr);
4075 
4076   bi     = merge->bi;
4077   bj     = merge->bj;
4078   buf_ri = merge->buf_ri;
4079   buf_rj = merge->buf_rj;
4080 
4081   ierr   = PetscMalloc1(size,&status);CHKERRQ(ierr);
4082   owners = merge->rowmap->range;
4083   len_s  = merge->len_s;
4084 
4085   /* send and recv matrix values */
4086   /*-----------------------------*/
4087   ierr = PetscObjectGetNewTag((PetscObject)mpimat,&taga);CHKERRQ(ierr);
4088   ierr = PetscPostIrecvScalar(comm,taga,merge->nrecv,merge->id_r,merge->len_r,&abuf_r,&r_waits);CHKERRQ(ierr);
4089 
4090   ierr = PetscMalloc1(merge->nsend+1,&s_waits);CHKERRQ(ierr);
4091   for (proc=0,k=0; proc<size; proc++) {
4092     if (!len_s[proc]) continue;
4093     i    = owners[proc];
4094     ierr = MPI_Isend(aa+ai[i],len_s[proc],MPIU_MATSCALAR,proc,taga,comm,s_waits+k);CHKERRQ(ierr);
4095     k++;
4096   }
4097 
4098   if (merge->nrecv) {ierr = MPI_Waitall(merge->nrecv,r_waits,status);CHKERRQ(ierr);}
4099   if (merge->nsend) {ierr = MPI_Waitall(merge->nsend,s_waits,status);CHKERRQ(ierr);}
4100   ierr = PetscFree(status);CHKERRQ(ierr);
4101 
4102   ierr = PetscFree(s_waits);CHKERRQ(ierr);
4103   ierr = PetscFree(r_waits);CHKERRQ(ierr);
4104 
4105   /* insert mat values of mpimat */
4106   /*----------------------------*/
4107   ierr = PetscMalloc1(N,&ba_i);CHKERRQ(ierr);
4108   ierr = PetscMalloc3(merge->nrecv,&buf_ri_k,merge->nrecv,&nextrow,merge->nrecv,&nextai);CHKERRQ(ierr);
4109 
4110   for (k=0; k<merge->nrecv; k++) {
4111     buf_ri_k[k] = buf_ri[k]; /* beginning of k-th recved i-structure */
4112     nrows       = *(buf_ri_k[k]);
4113     nextrow[k]  = buf_ri_k[k]+1;  /* next row number of k-th recved i-structure */
4114     nextai[k]   = buf_ri_k[k] + (nrows + 1); /* poins to the next i-structure of k-th recved i-structure  */
4115   }
4116 
4117   /* set values of ba */
4118   m = merge->rowmap->n;
4119   for (i=0; i<m; i++) {
4120     arow = owners[rank] + i;
4121     bj_i = bj+bi[i];  /* col indices of the i-th row of mpimat */
4122     bnzi = bi[i+1] - bi[i];
4123     ierr = PetscMemzero(ba_i,bnzi*sizeof(PetscScalar));CHKERRQ(ierr);
4124 
4125     /* add local non-zero vals of this proc's seqmat into ba */
4126     anzi   = ai[arow+1] - ai[arow];
4127     aj     = a->j + ai[arow];
4128     aa     = a->a + ai[arow];
4129     nextaj = 0;
4130     for (j=0; nextaj<anzi; j++) {
4131       if (*(bj_i + j) == aj[nextaj]) { /* bcol == acol */
4132         ba_i[j] += aa[nextaj++];
4133       }
4134     }
4135 
4136     /* add received vals into ba */
4137     for (k=0; k<merge->nrecv; k++) { /* k-th received message */
4138       /* i-th row */
4139       if (i == *nextrow[k]) {
4140         anzi   = *(nextai[k]+1) - *nextai[k];
4141         aj     = buf_rj[k] + *(nextai[k]);
4142         aa     = abuf_r[k] + *(nextai[k]);
4143         nextaj = 0;
4144         for (j=0; nextaj<anzi; j++) {
4145           if (*(bj_i + j) == aj[nextaj]) { /* bcol == acol */
4146             ba_i[j] += aa[nextaj++];
4147           }
4148         }
4149         nextrow[k]++; nextai[k]++;
4150       }
4151     }
4152     ierr = MatSetValues(mpimat,1,&arow,bnzi,bj_i,ba_i,INSERT_VALUES);CHKERRQ(ierr);
4153   }
4154   ierr = MatAssemblyBegin(mpimat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
4155   ierr = MatAssemblyEnd(mpimat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
4156 
4157   ierr = PetscFree(abuf_r[0]);CHKERRQ(ierr);
4158   ierr = PetscFree(abuf_r);CHKERRQ(ierr);
4159   ierr = PetscFree(ba_i);CHKERRQ(ierr);
4160   ierr = PetscFree3(buf_ri_k,nextrow,nextai);CHKERRQ(ierr);
4161   ierr = PetscLogEventEnd(MAT_Seqstompinum,seqmat,0,0,0);CHKERRQ(ierr);
4162   PetscFunctionReturn(0);
4163 }
4164 
4165 extern PetscErrorCode  MatDestroy_MPIAIJ_SeqsToMPI(Mat);
4166 
4167 #undef __FUNCT__
4168 #define __FUNCT__ "MatCreateMPIAIJSumSeqAIJSymbolic"
4169 PetscErrorCode  MatCreateMPIAIJSumSeqAIJSymbolic(MPI_Comm comm,Mat seqmat,PetscInt m,PetscInt n,Mat *mpimat)
4170 {
4171   PetscErrorCode      ierr;
4172   Mat                 B_mpi;
4173   Mat_SeqAIJ          *a=(Mat_SeqAIJ*)seqmat->data;
4174   PetscMPIInt         size,rank,tagi,tagj,*len_s,*len_si,*len_ri;
4175   PetscInt            **buf_rj,**buf_ri,**buf_ri_k;
4176   PetscInt            M=seqmat->rmap->n,N=seqmat->cmap->n,i,*owners,*ai=a->i,*aj=a->j;
4177   PetscInt            len,proc,*dnz,*onz,bs,cbs;
4178   PetscInt            k,anzi,*bi,*bj,*lnk,nlnk,arow,bnzi,nspacedouble=0;
4179   PetscInt            nrows,*buf_s,*buf_si,*buf_si_i,**nextrow,**nextai;
4180   MPI_Request         *si_waits,*sj_waits,*ri_waits,*rj_waits;
4181   MPI_Status          *status;
4182   PetscFreeSpaceList  free_space=NULL,current_space=NULL;
4183   PetscBT             lnkbt;
4184   Mat_Merge_SeqsToMPI *merge;
4185   PetscContainer      container;
4186 
4187   PetscFunctionBegin;
4188   ierr = PetscLogEventBegin(MAT_Seqstompisym,seqmat,0,0,0);CHKERRQ(ierr);
4189 
4190   /* make sure it is a PETSc comm */
4191   ierr = PetscCommDuplicate(comm,&comm,NULL);CHKERRQ(ierr);
4192   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
4193   ierr = MPI_Comm_rank(comm,&rank);CHKERRQ(ierr);
4194 
4195   ierr = PetscNew(&merge);CHKERRQ(ierr);
4196   ierr = PetscMalloc1(size,&status);CHKERRQ(ierr);
4197 
4198   /* determine row ownership */
4199   /*---------------------------------------------------------*/
4200   ierr = PetscLayoutCreate(comm,&merge->rowmap);CHKERRQ(ierr);
4201   ierr = PetscLayoutSetLocalSize(merge->rowmap,m);CHKERRQ(ierr);
4202   ierr = PetscLayoutSetSize(merge->rowmap,M);CHKERRQ(ierr);
4203   ierr = PetscLayoutSetBlockSize(merge->rowmap,1);CHKERRQ(ierr);
4204   ierr = PetscLayoutSetUp(merge->rowmap);CHKERRQ(ierr);
4205   ierr = PetscMalloc1(size,&len_si);CHKERRQ(ierr);
4206   ierr = PetscMalloc1(size,&merge->len_s);CHKERRQ(ierr);
4207 
4208   m      = merge->rowmap->n;
4209   owners = merge->rowmap->range;
4210 
4211   /* determine the number of messages to send, their lengths */
4212   /*---------------------------------------------------------*/
4213   len_s = merge->len_s;
4214 
4215   len          = 0; /* length of buf_si[] */
4216   merge->nsend = 0;
4217   for (proc=0; proc<size; proc++) {
4218     len_si[proc] = 0;
4219     if (proc == rank) {
4220       len_s[proc] = 0;
4221     } else {
4222       len_si[proc] = owners[proc+1] - owners[proc] + 1;
4223       len_s[proc]  = ai[owners[proc+1]] - ai[owners[proc]]; /* num of rows to be sent to [proc] */
4224     }
4225     if (len_s[proc]) {
4226       merge->nsend++;
4227       nrows = 0;
4228       for (i=owners[proc]; i<owners[proc+1]; i++) {
4229         if (ai[i+1] > ai[i]) nrows++;
4230       }
4231       len_si[proc] = 2*(nrows+1);
4232       len         += len_si[proc];
4233     }
4234   }
4235 
4236   /* determine the number and length of messages to receive for ij-structure */
4237   /*-------------------------------------------------------------------------*/
4238   ierr = PetscGatherNumberOfMessages(comm,NULL,len_s,&merge->nrecv);CHKERRQ(ierr);
4239   ierr = PetscGatherMessageLengths2(comm,merge->nsend,merge->nrecv,len_s,len_si,&merge->id_r,&merge->len_r,&len_ri);CHKERRQ(ierr);
4240 
4241   /* post the Irecv of j-structure */
4242   /*-------------------------------*/
4243   ierr = PetscCommGetNewTag(comm,&tagj);CHKERRQ(ierr);
4244   ierr = PetscPostIrecvInt(comm,tagj,merge->nrecv,merge->id_r,merge->len_r,&buf_rj,&rj_waits);CHKERRQ(ierr);
4245 
4246   /* post the Isend of j-structure */
4247   /*--------------------------------*/
4248   ierr = PetscMalloc2(merge->nsend,&si_waits,merge->nsend,&sj_waits);CHKERRQ(ierr);
4249 
4250   for (proc=0, k=0; proc<size; proc++) {
4251     if (!len_s[proc]) continue;
4252     i    = owners[proc];
4253     ierr = MPI_Isend(aj+ai[i],len_s[proc],MPIU_INT,proc,tagj,comm,sj_waits+k);CHKERRQ(ierr);
4254     k++;
4255   }
4256 
4257   /* receives and sends of j-structure are complete */
4258   /*------------------------------------------------*/
4259   if (merge->nrecv) {ierr = MPI_Waitall(merge->nrecv,rj_waits,status);CHKERRQ(ierr);}
4260   if (merge->nsend) {ierr = MPI_Waitall(merge->nsend,sj_waits,status);CHKERRQ(ierr);}
4261 
4262   /* send and recv i-structure */
4263   /*---------------------------*/
4264   ierr = PetscCommGetNewTag(comm,&tagi);CHKERRQ(ierr);
4265   ierr = PetscPostIrecvInt(comm,tagi,merge->nrecv,merge->id_r,len_ri,&buf_ri,&ri_waits);CHKERRQ(ierr);
4266 
4267   ierr   = PetscMalloc1(len+1,&buf_s);CHKERRQ(ierr);
4268   buf_si = buf_s;  /* points to the beginning of k-th msg to be sent */
4269   for (proc=0,k=0; proc<size; proc++) {
4270     if (!len_s[proc]) continue;
4271     /* form outgoing message for i-structure:
4272          buf_si[0]:                 nrows to be sent
4273                [1:nrows]:           row index (global)
4274                [nrows+1:2*nrows+1]: i-structure index
4275     */
4276     /*-------------------------------------------*/
4277     nrows       = len_si[proc]/2 - 1;
4278     buf_si_i    = buf_si + nrows+1;
4279     buf_si[0]   = nrows;
4280     buf_si_i[0] = 0;
4281     nrows       = 0;
4282     for (i=owners[proc]; i<owners[proc+1]; i++) {
4283       anzi = ai[i+1] - ai[i];
4284       if (anzi) {
4285         buf_si_i[nrows+1] = buf_si_i[nrows] + anzi; /* i-structure */
4286         buf_si[nrows+1]   = i-owners[proc]; /* local row index */
4287         nrows++;
4288       }
4289     }
4290     ierr = MPI_Isend(buf_si,len_si[proc],MPIU_INT,proc,tagi,comm,si_waits+k);CHKERRQ(ierr);
4291     k++;
4292     buf_si += len_si[proc];
4293   }
4294 
4295   if (merge->nrecv) {ierr = MPI_Waitall(merge->nrecv,ri_waits,status);CHKERRQ(ierr);}
4296   if (merge->nsend) {ierr = MPI_Waitall(merge->nsend,si_waits,status);CHKERRQ(ierr);}
4297 
4298   ierr = PetscInfo2(seqmat,"nsend: %D, nrecv: %D\n",merge->nsend,merge->nrecv);CHKERRQ(ierr);
4299   for (i=0; i<merge->nrecv; i++) {
4300     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);
4301   }
4302 
4303   ierr = PetscFree(len_si);CHKERRQ(ierr);
4304   ierr = PetscFree(len_ri);CHKERRQ(ierr);
4305   ierr = PetscFree(rj_waits);CHKERRQ(ierr);
4306   ierr = PetscFree2(si_waits,sj_waits);CHKERRQ(ierr);
4307   ierr = PetscFree(ri_waits);CHKERRQ(ierr);
4308   ierr = PetscFree(buf_s);CHKERRQ(ierr);
4309   ierr = PetscFree(status);CHKERRQ(ierr);
4310 
4311   /* compute a local seq matrix in each processor */
4312   /*----------------------------------------------*/
4313   /* allocate bi array and free space for accumulating nonzero column info */
4314   ierr  = PetscMalloc1(m+1,&bi);CHKERRQ(ierr);
4315   bi[0] = 0;
4316 
4317   /* create and initialize a linked list */
4318   nlnk = N+1;
4319   ierr = PetscLLCreate(N,N,nlnk,lnk,lnkbt);CHKERRQ(ierr);
4320 
4321   /* initial FreeSpace size is 2*(num of local nnz(seqmat)) */
4322   len  = ai[owners[rank+1]] - ai[owners[rank]];
4323   ierr = PetscFreeSpaceGet((PetscInt)(2*len+1),&free_space);CHKERRQ(ierr);
4324 
4325   current_space = free_space;
4326 
4327   /* determine symbolic info for each local row */
4328   ierr = PetscMalloc3(merge->nrecv,&buf_ri_k,merge->nrecv,&nextrow,merge->nrecv,&nextai);CHKERRQ(ierr);
4329 
4330   for (k=0; k<merge->nrecv; k++) {
4331     buf_ri_k[k] = buf_ri[k]; /* beginning of k-th recved i-structure */
4332     nrows       = *buf_ri_k[k];
4333     nextrow[k]  = buf_ri_k[k] + 1;  /* next row number of k-th recved i-structure */
4334     nextai[k]   = buf_ri_k[k] + (nrows + 1); /* poins to the next i-structure of k-th recved i-structure  */
4335   }
4336 
4337   ierr = MatPreallocateInitialize(comm,m,n,dnz,onz);CHKERRQ(ierr);
4338   len  = 0;
4339   for (i=0; i<m; i++) {
4340     bnzi = 0;
4341     /* add local non-zero cols of this proc's seqmat into lnk */
4342     arow  = owners[rank] + i;
4343     anzi  = ai[arow+1] - ai[arow];
4344     aj    = a->j + ai[arow];
4345     ierr  = PetscLLAddSorted(anzi,aj,N,nlnk,lnk,lnkbt);CHKERRQ(ierr);
4346     bnzi += nlnk;
4347     /* add received col data into lnk */
4348     for (k=0; k<merge->nrecv; k++) { /* k-th received message */
4349       if (i == *nextrow[k]) { /* i-th row */
4350         anzi  = *(nextai[k]+1) - *nextai[k];
4351         aj    = buf_rj[k] + *nextai[k];
4352         ierr  = PetscLLAddSorted(anzi,aj,N,nlnk,lnk,lnkbt);CHKERRQ(ierr);
4353         bnzi += nlnk;
4354         nextrow[k]++; nextai[k]++;
4355       }
4356     }
4357     if (len < bnzi) len = bnzi;  /* =max(bnzi) */
4358 
4359     /* if free space is not available, make more free space */
4360     if (current_space->local_remaining<bnzi) {
4361       ierr = PetscFreeSpaceGet(bnzi+current_space->total_array_size,&current_space);CHKERRQ(ierr);
4362       nspacedouble++;
4363     }
4364     /* copy data into free space, then initialize lnk */
4365     ierr = PetscLLClean(N,N,bnzi,lnk,current_space->array,lnkbt);CHKERRQ(ierr);
4366     ierr = MatPreallocateSet(i+owners[rank],bnzi,current_space->array,dnz,onz);CHKERRQ(ierr);
4367 
4368     current_space->array           += bnzi;
4369     current_space->local_used      += bnzi;
4370     current_space->local_remaining -= bnzi;
4371 
4372     bi[i+1] = bi[i] + bnzi;
4373   }
4374 
4375   ierr = PetscFree3(buf_ri_k,nextrow,nextai);CHKERRQ(ierr);
4376 
4377   ierr = PetscMalloc1(bi[m]+1,&bj);CHKERRQ(ierr);
4378   ierr = PetscFreeSpaceContiguous(&free_space,bj);CHKERRQ(ierr);
4379   ierr = PetscLLDestroy(lnk,lnkbt);CHKERRQ(ierr);
4380 
4381   /* create symbolic parallel matrix B_mpi */
4382   /*---------------------------------------*/
4383   ierr = MatGetBlockSizes(seqmat,&bs,&cbs);CHKERRQ(ierr);
4384   ierr = MatCreate(comm,&B_mpi);CHKERRQ(ierr);
4385   if (n==PETSC_DECIDE) {
4386     ierr = MatSetSizes(B_mpi,m,n,PETSC_DETERMINE,N);CHKERRQ(ierr);
4387   } else {
4388     ierr = MatSetSizes(B_mpi,m,n,PETSC_DETERMINE,PETSC_DETERMINE);CHKERRQ(ierr);
4389   }
4390   ierr = MatSetBlockSizes(B_mpi,bs,cbs);CHKERRQ(ierr);
4391   ierr = MatSetType(B_mpi,MATMPIAIJ);CHKERRQ(ierr);
4392   ierr = MatMPIAIJSetPreallocation(B_mpi,0,dnz,0,onz);CHKERRQ(ierr);
4393   ierr = MatPreallocateFinalize(dnz,onz);CHKERRQ(ierr);
4394   ierr = MatSetOption(B_mpi,MAT_NEW_NONZERO_ALLOCATION_ERR,PETSC_FALSE);CHKERRQ(ierr);
4395 
4396   /* B_mpi is not ready for use - assembly will be done by MatCreateMPIAIJSumSeqAIJNumeric() */
4397   B_mpi->assembled    = PETSC_FALSE;
4398   B_mpi->ops->destroy = MatDestroy_MPIAIJ_SeqsToMPI;
4399   merge->bi           = bi;
4400   merge->bj           = bj;
4401   merge->buf_ri       = buf_ri;
4402   merge->buf_rj       = buf_rj;
4403   merge->coi          = NULL;
4404   merge->coj          = NULL;
4405   merge->owners_co    = NULL;
4406 
4407   ierr = PetscCommDestroy(&comm);CHKERRQ(ierr);
4408 
4409   /* attach the supporting struct to B_mpi for reuse */
4410   ierr    = PetscContainerCreate(PETSC_COMM_SELF,&container);CHKERRQ(ierr);
4411   ierr    = PetscContainerSetPointer(container,merge);CHKERRQ(ierr);
4412   ierr    = PetscObjectCompose((PetscObject)B_mpi,"MatMergeSeqsToMPI",(PetscObject)container);CHKERRQ(ierr);
4413   ierr    = PetscContainerDestroy(&container);CHKERRQ(ierr);
4414   *mpimat = B_mpi;
4415 
4416   ierr = PetscLogEventEnd(MAT_Seqstompisym,seqmat,0,0,0);CHKERRQ(ierr);
4417   PetscFunctionReturn(0);
4418 }
4419 
4420 #undef __FUNCT__
4421 #define __FUNCT__ "MatCreateMPIAIJSumSeqAIJ"
4422 /*@C
4423       MatCreateMPIAIJSumSeqAIJ - Creates a MPIAIJ matrix by adding sequential
4424                  matrices from each processor
4425 
4426     Collective on MPI_Comm
4427 
4428    Input Parameters:
4429 +    comm - the communicators the parallel matrix will live on
4430 .    seqmat - the input sequential matrices
4431 .    m - number of local rows (or PETSC_DECIDE)
4432 .    n - number of local columns (or PETSC_DECIDE)
4433 -    scall - either MAT_INITIAL_MATRIX or MAT_REUSE_MATRIX
4434 
4435    Output Parameter:
4436 .    mpimat - the parallel matrix generated
4437 
4438     Level: advanced
4439 
4440    Notes:
4441      The dimensions of the sequential matrix in each processor MUST be the same.
4442      The input seqmat is included into the container "Mat_Merge_SeqsToMPI", and will be
4443      destroyed when mpimat is destroyed. Call PetscObjectQuery() to access seqmat.
4444 @*/
4445 PetscErrorCode  MatCreateMPIAIJSumSeqAIJ(MPI_Comm comm,Mat seqmat,PetscInt m,PetscInt n,MatReuse scall,Mat *mpimat)
4446 {
4447   PetscErrorCode ierr;
4448   PetscMPIInt    size;
4449 
4450   PetscFunctionBegin;
4451   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
4452   if (size == 1) {
4453     ierr = PetscLogEventBegin(MAT_Seqstompi,seqmat,0,0,0);CHKERRQ(ierr);
4454     if (scall == MAT_INITIAL_MATRIX) {
4455       ierr = MatDuplicate(seqmat,MAT_COPY_VALUES,mpimat);CHKERRQ(ierr);
4456     } else {
4457       ierr = MatCopy(seqmat,*mpimat,SAME_NONZERO_PATTERN);CHKERRQ(ierr);
4458     }
4459     ierr = PetscLogEventEnd(MAT_Seqstompi,seqmat,0,0,0);CHKERRQ(ierr);
4460     PetscFunctionReturn(0);
4461   }
4462   ierr = PetscLogEventBegin(MAT_Seqstompi,seqmat,0,0,0);CHKERRQ(ierr);
4463   if (scall == MAT_INITIAL_MATRIX) {
4464     ierr = MatCreateMPIAIJSumSeqAIJSymbolic(comm,seqmat,m,n,mpimat);CHKERRQ(ierr);
4465   }
4466   ierr = MatCreateMPIAIJSumSeqAIJNumeric(seqmat,*mpimat);CHKERRQ(ierr);
4467   ierr = PetscLogEventEnd(MAT_Seqstompi,seqmat,0,0,0);CHKERRQ(ierr);
4468   PetscFunctionReturn(0);
4469 }
4470 
4471 #undef __FUNCT__
4472 #define __FUNCT__ "MatMPIAIJGetLocalMat"
4473 /*@
4474      MatMPIAIJGetLocalMat - Creates a SeqAIJ from a MPIAIJ matrix by taking all its local rows and putting them into a sequential vector with
4475           mlocal rows and n columns. Where mlocal is the row count obtained with MatGetLocalSize() and n is the global column count obtained
4476           with MatGetSize()
4477 
4478     Not Collective
4479 
4480    Input Parameters:
4481 +    A - the matrix
4482 .    scall - either MAT_INITIAL_MATRIX or MAT_REUSE_MATRIX
4483 
4484    Output Parameter:
4485 .    A_loc - the local sequential matrix generated
4486 
4487     Level: developer
4488 
4489 .seealso: MatGetOwnerShipRange(), MatMPIAIJGetLocalMatCondensed()
4490 
4491 @*/
4492 PetscErrorCode  MatMPIAIJGetLocalMat(Mat A,MatReuse scall,Mat *A_loc)
4493 {
4494   PetscErrorCode ierr;
4495   Mat_MPIAIJ     *mpimat=(Mat_MPIAIJ*)A->data;
4496   Mat_SeqAIJ     *mat,*a,*b;
4497   PetscInt       *ai,*aj,*bi,*bj,*cmap=mpimat->garray;
4498   MatScalar      *aa,*ba,*cam;
4499   PetscScalar    *ca;
4500   PetscInt       am=A->rmap->n,i,j,k,cstart=A->cmap->rstart;
4501   PetscInt       *ci,*cj,col,ncols_d,ncols_o,jo;
4502   PetscBool      match;
4503   MPI_Comm       comm;
4504   PetscMPIInt    size;
4505 
4506   PetscFunctionBegin;
4507   ierr = PetscObjectTypeCompare((PetscObject)A,MATMPIAIJ,&match);CHKERRQ(ierr);
4508   if (!match) SETERRQ(PetscObjectComm((PetscObject)A), PETSC_ERR_SUP,"Requires MPIAIJ matrix as input");
4509   ierr = PetscObjectGetComm((PetscObject)A,&comm);CHKERRQ(ierr);
4510   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
4511   if (size == 1 && scall == MAT_REUSE_MATRIX) PetscFunctionReturn(0);
4512 
4513   ierr = PetscLogEventBegin(MAT_Getlocalmat,A,0,0,0);CHKERRQ(ierr);
4514   a = (Mat_SeqAIJ*)(mpimat->A)->data;
4515   b = (Mat_SeqAIJ*)(mpimat->B)->data;
4516   ai = a->i; aj = a->j; bi = b->i; bj = b->j;
4517   aa = a->a; ba = b->a;
4518   if (scall == MAT_INITIAL_MATRIX) {
4519     if (size == 1) {
4520       ierr = MatCreateSeqAIJWithArrays(PETSC_COMM_SELF,am,A->cmap->N,ai,aj,aa,A_loc);CHKERRQ(ierr);
4521       PetscFunctionReturn(0);
4522     }
4523 
4524     ierr  = PetscMalloc1(1+am,&ci);CHKERRQ(ierr);
4525     ci[0] = 0;
4526     for (i=0; i<am; i++) {
4527       ci[i+1] = ci[i] + (ai[i+1] - ai[i]) + (bi[i+1] - bi[i]);
4528     }
4529     ierr = PetscMalloc1(1+ci[am],&cj);CHKERRQ(ierr);
4530     ierr = PetscMalloc1(1+ci[am],&ca);CHKERRQ(ierr);
4531     k    = 0;
4532     for (i=0; i<am; i++) {
4533       ncols_o = bi[i+1] - bi[i];
4534       ncols_d = ai[i+1] - ai[i];
4535       /* off-diagonal portion of A */
4536       for (jo=0; jo<ncols_o; jo++) {
4537         col = cmap[*bj];
4538         if (col >= cstart) break;
4539         cj[k]   = col; bj++;
4540         ca[k++] = *ba++;
4541       }
4542       /* diagonal portion of A */
4543       for (j=0; j<ncols_d; j++) {
4544         cj[k]   = cstart + *aj++;
4545         ca[k++] = *aa++;
4546       }
4547       /* off-diagonal portion of A */
4548       for (j=jo; j<ncols_o; j++) {
4549         cj[k]   = cmap[*bj++];
4550         ca[k++] = *ba++;
4551       }
4552     }
4553     /* put together the new matrix */
4554     ierr = MatCreateSeqAIJWithArrays(PETSC_COMM_SELF,am,A->cmap->N,ci,cj,ca,A_loc);CHKERRQ(ierr);
4555     /* MatCreateSeqAIJWithArrays flags matrix so PETSc doesn't free the user's arrays. */
4556     /* Since these are PETSc arrays, change flags to free them as necessary. */
4557     mat          = (Mat_SeqAIJ*)(*A_loc)->data;
4558     mat->free_a  = PETSC_TRUE;
4559     mat->free_ij = PETSC_TRUE;
4560     mat->nonew   = 0;
4561   } else if (scall == MAT_REUSE_MATRIX) {
4562     mat=(Mat_SeqAIJ*)(*A_loc)->data;
4563     ci = mat->i; cj = mat->j; cam = mat->a;
4564     for (i=0; i<am; i++) {
4565       /* off-diagonal portion of A */
4566       ncols_o = bi[i+1] - bi[i];
4567       for (jo=0; jo<ncols_o; jo++) {
4568         col = cmap[*bj];
4569         if (col >= cstart) break;
4570         *cam++ = *ba++; bj++;
4571       }
4572       /* diagonal portion of A */
4573       ncols_d = ai[i+1] - ai[i];
4574       for (j=0; j<ncols_d; j++) *cam++ = *aa++;
4575       /* off-diagonal portion of A */
4576       for (j=jo; j<ncols_o; j++) {
4577         *cam++ = *ba++; bj++;
4578       }
4579     }
4580   } else SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONG,"Invalid MatReuse %d",(int)scall);
4581   ierr = PetscLogEventEnd(MAT_Getlocalmat,A,0,0,0);CHKERRQ(ierr);
4582   PetscFunctionReturn(0);
4583 }
4584 
4585 #undef __FUNCT__
4586 #define __FUNCT__ "MatMPIAIJGetLocalMatCondensed"
4587 /*@C
4588      MatMPIAIJGetLocalMatCondensed - Creates a SeqAIJ matrix from an MPIAIJ matrix by taking all its local rows and NON-ZERO columns
4589 
4590     Not Collective
4591 
4592    Input Parameters:
4593 +    A - the matrix
4594 .    scall - either MAT_INITIAL_MATRIX or MAT_REUSE_MATRIX
4595 -    row, col - index sets of rows and columns to extract (or NULL)
4596 
4597    Output Parameter:
4598 .    A_loc - the local sequential matrix generated
4599 
4600     Level: developer
4601 
4602 .seealso: MatGetOwnershipRange(), MatMPIAIJGetLocalMat()
4603 
4604 @*/
4605 PetscErrorCode  MatMPIAIJGetLocalMatCondensed(Mat A,MatReuse scall,IS *row,IS *col,Mat *A_loc)
4606 {
4607   Mat_MPIAIJ     *a=(Mat_MPIAIJ*)A->data;
4608   PetscErrorCode ierr;
4609   PetscInt       i,start,end,ncols,nzA,nzB,*cmap,imark,*idx;
4610   IS             isrowa,iscola;
4611   Mat            *aloc;
4612   PetscBool      match;
4613 
4614   PetscFunctionBegin;
4615   ierr = PetscObjectTypeCompare((PetscObject)A,MATMPIAIJ,&match);CHKERRQ(ierr);
4616   if (!match) SETERRQ(PetscObjectComm((PetscObject)A), PETSC_ERR_SUP,"Requires MPIAIJ matrix as input");
4617   ierr = PetscLogEventBegin(MAT_Getlocalmatcondensed,A,0,0,0);CHKERRQ(ierr);
4618   if (!row) {
4619     start = A->rmap->rstart; end = A->rmap->rend;
4620     ierr  = ISCreateStride(PETSC_COMM_SELF,end-start,start,1,&isrowa);CHKERRQ(ierr);
4621   } else {
4622     isrowa = *row;
4623   }
4624   if (!col) {
4625     start = A->cmap->rstart;
4626     cmap  = a->garray;
4627     nzA   = a->A->cmap->n;
4628     nzB   = a->B->cmap->n;
4629     ierr  = PetscMalloc1(nzA+nzB, &idx);CHKERRQ(ierr);
4630     ncols = 0;
4631     for (i=0; i<nzB; i++) {
4632       if (cmap[i] < start) idx[ncols++] = cmap[i];
4633       else break;
4634     }
4635     imark = i;
4636     for (i=0; i<nzA; i++) idx[ncols++] = start + i;
4637     for (i=imark; i<nzB; i++) idx[ncols++] = cmap[i];
4638     ierr = ISCreateGeneral(PETSC_COMM_SELF,ncols,idx,PETSC_OWN_POINTER,&iscola);CHKERRQ(ierr);
4639   } else {
4640     iscola = *col;
4641   }
4642   if (scall != MAT_INITIAL_MATRIX) {
4643     ierr    = PetscMalloc1(1,&aloc);CHKERRQ(ierr);
4644     aloc[0] = *A_loc;
4645   }
4646   ierr   = MatGetSubMatrices(A,1,&isrowa,&iscola,scall,&aloc);CHKERRQ(ierr);
4647   *A_loc = aloc[0];
4648   ierr   = PetscFree(aloc);CHKERRQ(ierr);
4649   if (!row) {
4650     ierr = ISDestroy(&isrowa);CHKERRQ(ierr);
4651   }
4652   if (!col) {
4653     ierr = ISDestroy(&iscola);CHKERRQ(ierr);
4654   }
4655   ierr = PetscLogEventEnd(MAT_Getlocalmatcondensed,A,0,0,0);CHKERRQ(ierr);
4656   PetscFunctionReturn(0);
4657 }
4658 
4659 #undef __FUNCT__
4660 #define __FUNCT__ "MatGetBrowsOfAcols"
4661 /*@C
4662     MatGetBrowsOfAcols - Creates a SeqAIJ matrix by taking rows of B that equal to nonzero columns of local A
4663 
4664     Collective on Mat
4665 
4666    Input Parameters:
4667 +    A,B - the matrices in mpiaij format
4668 .    scall - either MAT_INITIAL_MATRIX or MAT_REUSE_MATRIX
4669 -    rowb, colb - index sets of rows and columns of B to extract (or NULL)
4670 
4671    Output Parameter:
4672 +    rowb, colb - index sets of rows and columns of B to extract
4673 -    B_seq - the sequential matrix generated
4674 
4675     Level: developer
4676 
4677 @*/
4678 PetscErrorCode  MatGetBrowsOfAcols(Mat A,Mat B,MatReuse scall,IS *rowb,IS *colb,Mat *B_seq)
4679 {
4680   Mat_MPIAIJ     *a=(Mat_MPIAIJ*)A->data;
4681   PetscErrorCode ierr;
4682   PetscInt       *idx,i,start,ncols,nzA,nzB,*cmap,imark;
4683   IS             isrowb,iscolb;
4684   Mat            *bseq=NULL;
4685 
4686   PetscFunctionBegin;
4687   if (A->cmap->rstart != B->rmap->rstart || A->cmap->rend != B->rmap->rend) {
4688     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);
4689   }
4690   ierr = PetscLogEventBegin(MAT_GetBrowsOfAcols,A,B,0,0);CHKERRQ(ierr);
4691 
4692   if (scall == MAT_INITIAL_MATRIX) {
4693     start = A->cmap->rstart;
4694     cmap  = a->garray;
4695     nzA   = a->A->cmap->n;
4696     nzB   = a->B->cmap->n;
4697     ierr  = PetscMalloc1(nzA+nzB, &idx);CHKERRQ(ierr);
4698     ncols = 0;
4699     for (i=0; i<nzB; i++) {  /* row < local row index */
4700       if (cmap[i] < start) idx[ncols++] = cmap[i];
4701       else break;
4702     }
4703     imark = i;
4704     for (i=0; i<nzA; i++) idx[ncols++] = start + i;  /* local rows */
4705     for (i=imark; i<nzB; i++) idx[ncols++] = cmap[i]; /* row > local row index */
4706     ierr = ISCreateGeneral(PETSC_COMM_SELF,ncols,idx,PETSC_OWN_POINTER,&isrowb);CHKERRQ(ierr);
4707     ierr = ISCreateStride(PETSC_COMM_SELF,B->cmap->N,0,1,&iscolb);CHKERRQ(ierr);
4708   } else {
4709     if (!rowb || !colb) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_SUP,"IS rowb and colb must be provided for MAT_REUSE_MATRIX");
4710     isrowb  = *rowb; iscolb = *colb;
4711     ierr    = PetscMalloc1(1,&bseq);CHKERRQ(ierr);
4712     bseq[0] = *B_seq;
4713   }
4714   ierr   = MatGetSubMatrices(B,1,&isrowb,&iscolb,scall,&bseq);CHKERRQ(ierr);
4715   *B_seq = bseq[0];
4716   ierr   = PetscFree(bseq);CHKERRQ(ierr);
4717   if (!rowb) {
4718     ierr = ISDestroy(&isrowb);CHKERRQ(ierr);
4719   } else {
4720     *rowb = isrowb;
4721   }
4722   if (!colb) {
4723     ierr = ISDestroy(&iscolb);CHKERRQ(ierr);
4724   } else {
4725     *colb = iscolb;
4726   }
4727   ierr = PetscLogEventEnd(MAT_GetBrowsOfAcols,A,B,0,0);CHKERRQ(ierr);
4728   PetscFunctionReturn(0);
4729 }
4730 
4731 #undef __FUNCT__
4732 #define __FUNCT__ "MatGetBrowsOfAoCols_MPIAIJ"
4733 /*
4734     MatGetBrowsOfAoCols_MPIAIJ - Creates a SeqAIJ matrix by taking rows of B that equal to nonzero columns
4735     of the OFF-DIAGONAL portion of local A
4736 
4737     Collective on Mat
4738 
4739    Input Parameters:
4740 +    A,B - the matrices in mpiaij format
4741 -    scall - either MAT_INITIAL_MATRIX or MAT_REUSE_MATRIX
4742 
4743    Output Parameter:
4744 +    startsj_s - starting point in B's sending j-arrays, saved for MAT_REUSE (or NULL)
4745 .    startsj_r - starting point in B's receiving j-arrays, saved for MAT_REUSE (or NULL)
4746 .    bufa_ptr - array for sending matrix values, saved for MAT_REUSE (or NULL)
4747 -    B_oth - the sequential matrix generated with size aBn=a->B->cmap->n by B->cmap->N
4748 
4749     Level: developer
4750 
4751 */
4752 PetscErrorCode  MatGetBrowsOfAoCols_MPIAIJ(Mat A,Mat B,MatReuse scall,PetscInt **startsj_s,PetscInt **startsj_r,MatScalar **bufa_ptr,Mat *B_oth)
4753 {
4754   VecScatter_MPI_General *gen_to,*gen_from;
4755   PetscErrorCode         ierr;
4756   Mat_MPIAIJ             *a=(Mat_MPIAIJ*)A->data;
4757   Mat_SeqAIJ             *b_oth;
4758   VecScatter             ctx =a->Mvctx;
4759   MPI_Comm               comm;
4760   PetscMPIInt            *rprocs,*sprocs,tag=((PetscObject)ctx)->tag,rank;
4761   PetscInt               *rowlen,*bufj,*bufJ,ncols,aBn=a->B->cmap->n,row,*b_othi,*b_othj;
4762   PetscScalar            *rvalues,*svalues;
4763   MatScalar              *b_otha,*bufa,*bufA;
4764   PetscInt               i,j,k,l,ll,nrecvs,nsends,nrows,*srow,*rstarts,*rstartsj = 0,*sstarts,*sstartsj,len;
4765   MPI_Request            *rwaits = NULL,*swaits = NULL;
4766   MPI_Status             *sstatus,rstatus;
4767   PetscMPIInt            jj,size;
4768   PetscInt               *cols,sbs,rbs;
4769   PetscScalar            *vals;
4770 
4771   PetscFunctionBegin;
4772   ierr = PetscObjectGetComm((PetscObject)A,&comm);CHKERRQ(ierr);
4773   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
4774 
4775   if (A->cmap->rstart != B->rmap->rstart || A->cmap->rend != B->rmap->rend) {
4776     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);
4777   }
4778   ierr = PetscLogEventBegin(MAT_GetBrowsOfAocols,A,B,0,0);CHKERRQ(ierr);
4779   ierr = MPI_Comm_rank(comm,&rank);CHKERRQ(ierr);
4780 
4781   gen_to   = (VecScatter_MPI_General*)ctx->todata;
4782   gen_from = (VecScatter_MPI_General*)ctx->fromdata;
4783   rvalues  = gen_from->values; /* holds the length of receiving row */
4784   svalues  = gen_to->values;   /* holds the length of sending row */
4785   nrecvs   = gen_from->n;
4786   nsends   = gen_to->n;
4787 
4788   ierr    = PetscMalloc2(nrecvs,&rwaits,nsends,&swaits);CHKERRQ(ierr);
4789   srow    = gen_to->indices;    /* local row index to be sent */
4790   sstarts = gen_to->starts;
4791   sprocs  = gen_to->procs;
4792   sstatus = gen_to->sstatus;
4793   sbs     = gen_to->bs;
4794   rstarts = gen_from->starts;
4795   rprocs  = gen_from->procs;
4796   rbs     = gen_from->bs;
4797 
4798   if (!startsj_s || !bufa_ptr) scall = MAT_INITIAL_MATRIX;
4799   if (scall == MAT_INITIAL_MATRIX) {
4800     /* i-array */
4801     /*---------*/
4802     /*  post receives */
4803     for (i=0; i<nrecvs; i++) {
4804       rowlen = (PetscInt*)rvalues + rstarts[i]*rbs;
4805       nrows  = (rstarts[i+1]-rstarts[i])*rbs; /* num of indices to be received */
4806       ierr   = MPI_Irecv(rowlen,nrows,MPIU_INT,rprocs[i],tag,comm,rwaits+i);CHKERRQ(ierr);
4807     }
4808 
4809     /* pack the outgoing message */
4810     ierr = PetscMalloc2(nsends+1,&sstartsj,nrecvs+1,&rstartsj);CHKERRQ(ierr);
4811 
4812     sstartsj[0] = 0;
4813     rstartsj[0] = 0;
4814     len         = 0; /* total length of j or a array to be sent */
4815     k           = 0;
4816     for (i=0; i<nsends; i++) {
4817       rowlen = (PetscInt*)svalues + sstarts[i]*sbs;
4818       nrows  = sstarts[i+1]-sstarts[i]; /* num of block rows */
4819       for (j=0; j<nrows; j++) {
4820         row = srow[k] + B->rmap->range[rank]; /* global row idx */
4821         for (l=0; l<sbs; l++) {
4822           ierr = MatGetRow_MPIAIJ(B,row+l,&ncols,NULL,NULL);CHKERRQ(ierr); /* rowlength */
4823 
4824           rowlen[j*sbs+l] = ncols;
4825 
4826           len += ncols;
4827           ierr = MatRestoreRow_MPIAIJ(B,row+l,&ncols,NULL,NULL);CHKERRQ(ierr);
4828         }
4829         k++;
4830       }
4831       ierr = MPI_Isend(rowlen,nrows*sbs,MPIU_INT,sprocs[i],tag,comm,swaits+i);CHKERRQ(ierr);
4832 
4833       sstartsj[i+1] = len;  /* starting point of (i+1)-th outgoing msg in bufj and bufa */
4834     }
4835     /* recvs and sends of i-array are completed */
4836     i = nrecvs;
4837     while (i--) {
4838       ierr = MPI_Waitany(nrecvs,rwaits,&jj,&rstatus);CHKERRQ(ierr);
4839     }
4840     if (nsends) {ierr = MPI_Waitall(nsends,swaits,sstatus);CHKERRQ(ierr);}
4841 
4842     /* allocate buffers for sending j and a arrays */
4843     ierr = PetscMalloc1(len+1,&bufj);CHKERRQ(ierr);
4844     ierr = PetscMalloc1(len+1,&bufa);CHKERRQ(ierr);
4845 
4846     /* create i-array of B_oth */
4847     ierr = PetscMalloc1(aBn+2,&b_othi);CHKERRQ(ierr);
4848 
4849     b_othi[0] = 0;
4850     len       = 0; /* total length of j or a array to be received */
4851     k         = 0;
4852     for (i=0; i<nrecvs; i++) {
4853       rowlen = (PetscInt*)rvalues + rstarts[i]*rbs;
4854       nrows  = rbs*(rstarts[i+1]-rstarts[i]); /* num of rows to be recieved */
4855       for (j=0; j<nrows; j++) {
4856         b_othi[k+1] = b_othi[k] + rowlen[j];
4857         len        += rowlen[j]; k++;
4858       }
4859       rstartsj[i+1] = len; /* starting point of (i+1)-th incoming msg in bufj and bufa */
4860     }
4861 
4862     /* allocate space for j and a arrrays of B_oth */
4863     ierr = PetscMalloc1(b_othi[aBn]+1,&b_othj);CHKERRQ(ierr);
4864     ierr = PetscMalloc1(b_othi[aBn]+1,&b_otha);CHKERRQ(ierr);
4865 
4866     /* j-array */
4867     /*---------*/
4868     /*  post receives of j-array */
4869     for (i=0; i<nrecvs; i++) {
4870       nrows = rstartsj[i+1]-rstartsj[i]; /* length of the msg received */
4871       ierr  = MPI_Irecv(b_othj+rstartsj[i],nrows,MPIU_INT,rprocs[i],tag,comm,rwaits+i);CHKERRQ(ierr);
4872     }
4873 
4874     /* pack the outgoing message j-array */
4875     k = 0;
4876     for (i=0; i<nsends; i++) {
4877       nrows = sstarts[i+1]-sstarts[i]; /* num of block rows */
4878       bufJ  = bufj+sstartsj[i];
4879       for (j=0; j<nrows; j++) {
4880         row = srow[k++] + B->rmap->range[rank];  /* global row idx */
4881         for (ll=0; ll<sbs; ll++) {
4882           ierr = MatGetRow_MPIAIJ(B,row+ll,&ncols,&cols,NULL);CHKERRQ(ierr);
4883           for (l=0; l<ncols; l++) {
4884             *bufJ++ = cols[l];
4885           }
4886           ierr = MatRestoreRow_MPIAIJ(B,row+ll,&ncols,&cols,NULL);CHKERRQ(ierr);
4887         }
4888       }
4889       ierr = MPI_Isend(bufj+sstartsj[i],sstartsj[i+1]-sstartsj[i],MPIU_INT,sprocs[i],tag,comm,swaits+i);CHKERRQ(ierr);
4890     }
4891 
4892     /* recvs and sends of j-array are completed */
4893     i = nrecvs;
4894     while (i--) {
4895       ierr = MPI_Waitany(nrecvs,rwaits,&jj,&rstatus);CHKERRQ(ierr);
4896     }
4897     if (nsends) {ierr = MPI_Waitall(nsends,swaits,sstatus);CHKERRQ(ierr);}
4898   } else if (scall == MAT_REUSE_MATRIX) {
4899     sstartsj = *startsj_s;
4900     rstartsj = *startsj_r;
4901     bufa     = *bufa_ptr;
4902     b_oth    = (Mat_SeqAIJ*)(*B_oth)->data;
4903     b_otha   = b_oth->a;
4904   } else SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE, "Matrix P does not posses an object container");
4905 
4906   /* a-array */
4907   /*---------*/
4908   /*  post receives of a-array */
4909   for (i=0; i<nrecvs; i++) {
4910     nrows = rstartsj[i+1]-rstartsj[i]; /* length of the msg received */
4911     ierr  = MPI_Irecv(b_otha+rstartsj[i],nrows,MPIU_SCALAR,rprocs[i],tag,comm,rwaits+i);CHKERRQ(ierr);
4912   }
4913 
4914   /* pack the outgoing message a-array */
4915   k = 0;
4916   for (i=0; i<nsends; i++) {
4917     nrows = sstarts[i+1]-sstarts[i]; /* num of block rows */
4918     bufA  = bufa+sstartsj[i];
4919     for (j=0; j<nrows; j++) {
4920       row = srow[k++] + B->rmap->range[rank];  /* global row idx */
4921       for (ll=0; ll<sbs; ll++) {
4922         ierr = MatGetRow_MPIAIJ(B,row+ll,&ncols,NULL,&vals);CHKERRQ(ierr);
4923         for (l=0; l<ncols; l++) {
4924           *bufA++ = vals[l];
4925         }
4926         ierr = MatRestoreRow_MPIAIJ(B,row+ll,&ncols,NULL,&vals);CHKERRQ(ierr);
4927       }
4928     }
4929     ierr = MPI_Isend(bufa+sstartsj[i],sstartsj[i+1]-sstartsj[i],MPIU_SCALAR,sprocs[i],tag,comm,swaits+i);CHKERRQ(ierr);
4930   }
4931   /* recvs and sends of a-array are completed */
4932   i = nrecvs;
4933   while (i--) {
4934     ierr = MPI_Waitany(nrecvs,rwaits,&jj,&rstatus);CHKERRQ(ierr);
4935   }
4936   if (nsends) {ierr = MPI_Waitall(nsends,swaits,sstatus);CHKERRQ(ierr);}
4937   ierr = PetscFree2(rwaits,swaits);CHKERRQ(ierr);
4938 
4939   if (scall == MAT_INITIAL_MATRIX) {
4940     /* put together the new matrix */
4941     ierr = MatCreateSeqAIJWithArrays(PETSC_COMM_SELF,aBn,B->cmap->N,b_othi,b_othj,b_otha,B_oth);CHKERRQ(ierr);
4942 
4943     /* MatCreateSeqAIJWithArrays flags matrix so PETSc doesn't free the user's arrays. */
4944     /* Since these are PETSc arrays, change flags to free them as necessary. */
4945     b_oth          = (Mat_SeqAIJ*)(*B_oth)->data;
4946     b_oth->free_a  = PETSC_TRUE;
4947     b_oth->free_ij = PETSC_TRUE;
4948     b_oth->nonew   = 0;
4949 
4950     ierr = PetscFree(bufj);CHKERRQ(ierr);
4951     if (!startsj_s || !bufa_ptr) {
4952       ierr = PetscFree2(sstartsj,rstartsj);CHKERRQ(ierr);
4953       ierr = PetscFree(bufa_ptr);CHKERRQ(ierr);
4954     } else {
4955       *startsj_s = sstartsj;
4956       *startsj_r = rstartsj;
4957       *bufa_ptr  = bufa;
4958     }
4959   }
4960   ierr = PetscLogEventEnd(MAT_GetBrowsOfAocols,A,B,0,0);CHKERRQ(ierr);
4961   PetscFunctionReturn(0);
4962 }
4963 
4964 #undef __FUNCT__
4965 #define __FUNCT__ "MatGetCommunicationStructs"
4966 /*@C
4967   MatGetCommunicationStructs - Provides access to the communication structures used in matrix-vector multiplication.
4968 
4969   Not Collective
4970 
4971   Input Parameters:
4972 . A - The matrix in mpiaij format
4973 
4974   Output Parameter:
4975 + lvec - The local vector holding off-process values from the argument to a matrix-vector product
4976 . colmap - A map from global column index to local index into lvec
4977 - multScatter - A scatter from the argument of a matrix-vector product to lvec
4978 
4979   Level: developer
4980 
4981 @*/
4982 #if defined(PETSC_USE_CTABLE)
4983 PetscErrorCode  MatGetCommunicationStructs(Mat A, Vec *lvec, PetscTable *colmap, VecScatter *multScatter)
4984 #else
4985 PetscErrorCode  MatGetCommunicationStructs(Mat A, Vec *lvec, PetscInt *colmap[], VecScatter *multScatter)
4986 #endif
4987 {
4988   Mat_MPIAIJ *a;
4989 
4990   PetscFunctionBegin;
4991   PetscValidHeaderSpecific(A, MAT_CLASSID, 1);
4992   PetscValidPointer(lvec, 2);
4993   PetscValidPointer(colmap, 3);
4994   PetscValidPointer(multScatter, 4);
4995   a = (Mat_MPIAIJ*) A->data;
4996   if (lvec) *lvec = a->lvec;
4997   if (colmap) *colmap = a->colmap;
4998   if (multScatter) *multScatter = a->Mvctx;
4999   PetscFunctionReturn(0);
5000 }
5001 
5002 PETSC_EXTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJCRL(Mat,MatType,MatReuse,Mat*);
5003 PETSC_EXTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJPERM(Mat,MatType,MatReuse,Mat*);
5004 PETSC_EXTERN PetscErrorCode MatConvert_MPIAIJ_MPISBAIJ(Mat,MatType,MatReuse,Mat*);
5005 #if defined(PETSC_HAVE_ELEMENTAL)
5006 PETSC_EXTERN PetscErrorCode MatConvert_MPIAIJ_Elemental(Mat,MatType,MatReuse,Mat*);
5007 #endif
5008 
5009 #undef __FUNCT__
5010 #define __FUNCT__ "MatMatMultNumeric_MPIDense_MPIAIJ"
5011 /*
5012     Computes (B'*A')' since computing B*A directly is untenable
5013 
5014                n                       p                          p
5015         (              )       (              )         (                  )
5016       m (      A       )  *  n (       B      )   =   m (         C        )
5017         (              )       (              )         (                  )
5018 
5019 */
5020 PetscErrorCode MatMatMultNumeric_MPIDense_MPIAIJ(Mat A,Mat B,Mat C)
5021 {
5022   PetscErrorCode ierr;
5023   Mat            At,Bt,Ct;
5024 
5025   PetscFunctionBegin;
5026   ierr = MatTranspose(A,MAT_INITIAL_MATRIX,&At);CHKERRQ(ierr);
5027   ierr = MatTranspose(B,MAT_INITIAL_MATRIX,&Bt);CHKERRQ(ierr);
5028   ierr = MatMatMult(Bt,At,MAT_INITIAL_MATRIX,1.0,&Ct);CHKERRQ(ierr);
5029   ierr = MatDestroy(&At);CHKERRQ(ierr);
5030   ierr = MatDestroy(&Bt);CHKERRQ(ierr);
5031   ierr = MatTranspose(Ct,MAT_REUSE_MATRIX,&C);CHKERRQ(ierr);
5032   ierr = MatDestroy(&Ct);CHKERRQ(ierr);
5033   PetscFunctionReturn(0);
5034 }
5035 
5036 #undef __FUNCT__
5037 #define __FUNCT__ "MatMatMultSymbolic_MPIDense_MPIAIJ"
5038 PetscErrorCode MatMatMultSymbolic_MPIDense_MPIAIJ(Mat A,Mat B,PetscReal fill,Mat *C)
5039 {
5040   PetscErrorCode ierr;
5041   PetscInt       m=A->rmap->n,n=B->cmap->n;
5042   Mat            Cmat;
5043 
5044   PetscFunctionBegin;
5045   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);
5046   ierr = MatCreate(PetscObjectComm((PetscObject)A),&Cmat);CHKERRQ(ierr);
5047   ierr = MatSetSizes(Cmat,m,n,PETSC_DETERMINE,PETSC_DETERMINE);CHKERRQ(ierr);
5048   ierr = MatSetBlockSizesFromMats(Cmat,A,B);CHKERRQ(ierr);
5049   ierr = MatSetType(Cmat,MATMPIDENSE);CHKERRQ(ierr);
5050   ierr = MatMPIDenseSetPreallocation(Cmat,NULL);CHKERRQ(ierr);
5051   ierr = MatAssemblyBegin(Cmat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
5052   ierr = MatAssemblyEnd(Cmat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
5053 
5054   Cmat->ops->matmultnumeric = MatMatMultNumeric_MPIDense_MPIAIJ;
5055 
5056   *C = Cmat;
5057   PetscFunctionReturn(0);
5058 }
5059 
5060 /* ----------------------------------------------------------------*/
5061 #undef __FUNCT__
5062 #define __FUNCT__ "MatMatMult_MPIDense_MPIAIJ"
5063 PetscErrorCode MatMatMult_MPIDense_MPIAIJ(Mat A,Mat B,MatReuse scall,PetscReal fill,Mat *C)
5064 {
5065   PetscErrorCode ierr;
5066 
5067   PetscFunctionBegin;
5068   if (scall == MAT_INITIAL_MATRIX) {
5069     ierr = PetscLogEventBegin(MAT_MatMultSymbolic,A,B,0,0);CHKERRQ(ierr);
5070     ierr = MatMatMultSymbolic_MPIDense_MPIAIJ(A,B,fill,C);CHKERRQ(ierr);
5071     ierr = PetscLogEventEnd(MAT_MatMultSymbolic,A,B,0,0);CHKERRQ(ierr);
5072   }
5073   ierr = PetscLogEventBegin(MAT_MatMultNumeric,A,B,0,0);CHKERRQ(ierr);
5074   ierr = MatMatMultNumeric_MPIDense_MPIAIJ(A,B,*C);CHKERRQ(ierr);
5075   ierr = PetscLogEventEnd(MAT_MatMultNumeric,A,B,0,0);CHKERRQ(ierr);
5076   PetscFunctionReturn(0);
5077 }
5078 
5079 /*MC
5080    MATMPIAIJ - MATMPIAIJ = "mpiaij" - A matrix type to be used for parallel sparse matrices.
5081 
5082    Options Database Keys:
5083 . -mat_type mpiaij - sets the matrix type to "mpiaij" during a call to MatSetFromOptions()
5084 
5085   Level: beginner
5086 
5087 .seealso: MatCreateAIJ()
5088 M*/
5089 
5090 #undef __FUNCT__
5091 #define __FUNCT__ "MatCreate_MPIAIJ"
5092 PETSC_EXTERN PetscErrorCode MatCreate_MPIAIJ(Mat B)
5093 {
5094   Mat_MPIAIJ     *b;
5095   PetscErrorCode ierr;
5096   PetscMPIInt    size;
5097 
5098   PetscFunctionBegin;
5099   ierr = MPI_Comm_size(PetscObjectComm((PetscObject)B),&size);CHKERRQ(ierr);
5100 
5101   ierr          = PetscNewLog(B,&b);CHKERRQ(ierr);
5102   B->data       = (void*)b;
5103   ierr          = PetscMemcpy(B->ops,&MatOps_Values,sizeof(struct _MatOps));CHKERRQ(ierr);
5104   B->assembled  = PETSC_FALSE;
5105   B->insertmode = NOT_SET_VALUES;
5106   b->size       = size;
5107 
5108   ierr = MPI_Comm_rank(PetscObjectComm((PetscObject)B),&b->rank);CHKERRQ(ierr);
5109 
5110   /* build cache for off array entries formed */
5111   ierr = MatStashCreate_Private(PetscObjectComm((PetscObject)B),1,&B->stash);CHKERRQ(ierr);
5112 
5113   b->donotstash  = PETSC_FALSE;
5114   b->colmap      = 0;
5115   b->garray      = 0;
5116   b->roworiented = PETSC_TRUE;
5117 
5118   /* stuff used for matrix vector multiply */
5119   b->lvec  = NULL;
5120   b->Mvctx = NULL;
5121 
5122   /* stuff for MatGetRow() */
5123   b->rowindices   = 0;
5124   b->rowvalues    = 0;
5125   b->getrowactive = PETSC_FALSE;
5126 
5127   /* flexible pointer used in CUSP/CUSPARSE classes */
5128   b->spptr = NULL;
5129 
5130   ierr = PetscObjectComposeFunction((PetscObject)B,"MatMPIAIJSetUseScalableIncreaseOverlap_C",MatMPIAIJSetUseScalableIncreaseOverlap_MPIAIJ);CHKERRQ(ierr);
5131   ierr = PetscObjectComposeFunction((PetscObject)B,"MatStoreValues_C",MatStoreValues_MPIAIJ);CHKERRQ(ierr);
5132   ierr = PetscObjectComposeFunction((PetscObject)B,"MatRetrieveValues_C",MatRetrieveValues_MPIAIJ);CHKERRQ(ierr);
5133   ierr = PetscObjectComposeFunction((PetscObject)B,"MatGetDiagonalBlock_C",MatGetDiagonalBlock_MPIAIJ);CHKERRQ(ierr);
5134   ierr = PetscObjectComposeFunction((PetscObject)B,"MatIsTranspose_C",MatIsTranspose_MPIAIJ);CHKERRQ(ierr);
5135   ierr = PetscObjectComposeFunction((PetscObject)B,"MatMPIAIJSetPreallocation_C",MatMPIAIJSetPreallocation_MPIAIJ);CHKERRQ(ierr);
5136   ierr = PetscObjectComposeFunction((PetscObject)B,"MatMPIAIJSetPreallocationCSR_C",MatMPIAIJSetPreallocationCSR_MPIAIJ);CHKERRQ(ierr);
5137   ierr = PetscObjectComposeFunction((PetscObject)B,"MatDiagonalScaleLocal_C",MatDiagonalScaleLocal_MPIAIJ);CHKERRQ(ierr);
5138   ierr = PetscObjectComposeFunction((PetscObject)B,"MatConvert_mpiaij_mpiaijperm_C",MatConvert_MPIAIJ_MPIAIJPERM);CHKERRQ(ierr);
5139   ierr = PetscObjectComposeFunction((PetscObject)B,"MatConvert_mpiaij_mpiaijcrl_C",MatConvert_MPIAIJ_MPIAIJCRL);CHKERRQ(ierr);
5140   ierr = PetscObjectComposeFunction((PetscObject)B,"MatConvert_mpiaij_mpisbaij_C",MatConvert_MPIAIJ_MPISBAIJ);CHKERRQ(ierr);
5141 #if defined(PETSC_HAVE_ELEMENTAL)
5142   ierr = PetscObjectComposeFunction((PetscObject)B,"MatConvert_mpiaij_elemental_C",MatConvert_MPIAIJ_Elemental);CHKERRQ(ierr);
5143 #endif
5144   ierr = PetscObjectComposeFunction((PetscObject)B,"MatMatMult_mpidense_mpiaij_C",MatMatMult_MPIDense_MPIAIJ);CHKERRQ(ierr);
5145   ierr = PetscObjectComposeFunction((PetscObject)B,"MatMatMultSymbolic_mpidense_mpiaij_C",MatMatMultSymbolic_MPIDense_MPIAIJ);CHKERRQ(ierr);
5146   ierr = PetscObjectComposeFunction((PetscObject)B,"MatMatMultNumeric_mpidense_mpiaij_C",MatMatMultNumeric_MPIDense_MPIAIJ);CHKERRQ(ierr);
5147   ierr = PetscObjectChangeTypeName((PetscObject)B,MATMPIAIJ);CHKERRQ(ierr);
5148   PetscFunctionReturn(0);
5149 }
5150 
5151 #undef __FUNCT__
5152 #define __FUNCT__ "MatCreateMPIAIJWithSplitArrays"
5153 /*@C
5154      MatCreateMPIAIJWithSplitArrays - creates a MPI AIJ matrix using arrays that contain the "diagonal"
5155          and "off-diagonal" part of the matrix in CSR format.
5156 
5157    Collective on MPI_Comm
5158 
5159    Input Parameters:
5160 +  comm - MPI communicator
5161 .  m - number of local rows (Cannot be PETSC_DECIDE)
5162 .  n - This value should be the same as the local size used in creating the
5163        x vector for the matrix-vector product y = Ax. (or PETSC_DECIDE to have
5164        calculated if N is given) For square matrices n is almost always m.
5165 .  M - number of global rows (or PETSC_DETERMINE to have calculated if m is given)
5166 .  N - number of global columns (or PETSC_DETERMINE to have calculated if n is given)
5167 .   i - row indices for "diagonal" portion of matrix
5168 .   j - column indices
5169 .   a - matrix values
5170 .   oi - row indices for "off-diagonal" portion of matrix
5171 .   oj - column indices
5172 -   oa - matrix values
5173 
5174    Output Parameter:
5175 .   mat - the matrix
5176 
5177    Level: advanced
5178 
5179    Notes:
5180        The i, j, and a arrays ARE NOT copied by this routine into the internal format used by PETSc. The user
5181        must free the arrays once the matrix has been destroyed and not before.
5182 
5183        The i and j indices are 0 based
5184 
5185        See MatCreateAIJ() for the definition of "diagonal" and "off-diagonal" portion of the matrix
5186 
5187        This sets local rows and cannot be used to set off-processor values.
5188 
5189        Use of this routine is discouraged because it is inflexible and cumbersome to use. It is extremely rare that a
5190        legacy application natively assembles into exactly this split format. The code to do so is nontrivial and does
5191        not easily support in-place reassembly. It is recommended to use MatSetValues() (or a variant thereof) because
5192        the resulting assembly is easier to implement, will work with any matrix format, and the user does not have to
5193        keep track of the underlying array. Use MatSetOption(A,MAT_IGNORE_OFF_PROC_ENTRIES,PETSC_TRUE) to disable all
5194        communication if it is known that only local entries will be set.
5195 
5196 .keywords: matrix, aij, compressed row, sparse, parallel
5197 
5198 .seealso: MatCreate(), MatCreateSeqAIJ(), MatSetValues(), MatMPIAIJSetPreallocation(), MatMPIAIJSetPreallocationCSR(),
5199           MPIAIJ, MatCreateAIJ(), MatCreateMPIAIJWithArrays()
5200 @*/
5201 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)
5202 {
5203   PetscErrorCode ierr;
5204   Mat_MPIAIJ     *maij;
5205 
5206   PetscFunctionBegin;
5207   if (m < 0) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"local number of rows (m) cannot be PETSC_DECIDE, or negative");
5208   if (i[0]) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"i (row indices) must start with 0");
5209   if (oi[0]) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"oi (row indices) must start with 0");
5210   ierr = MatCreate(comm,mat);CHKERRQ(ierr);
5211   ierr = MatSetSizes(*mat,m,n,M,N);CHKERRQ(ierr);
5212   ierr = MatSetType(*mat,MATMPIAIJ);CHKERRQ(ierr);
5213   maij = (Mat_MPIAIJ*) (*mat)->data;
5214 
5215   (*mat)->preallocated = PETSC_TRUE;
5216 
5217   ierr = PetscLayoutSetUp((*mat)->rmap);CHKERRQ(ierr);
5218   ierr = PetscLayoutSetUp((*mat)->cmap);CHKERRQ(ierr);
5219 
5220   ierr = MatCreateSeqAIJWithArrays(PETSC_COMM_SELF,m,n,i,j,a,&maij->A);CHKERRQ(ierr);
5221   ierr = MatCreateSeqAIJWithArrays(PETSC_COMM_SELF,m,(*mat)->cmap->N,oi,oj,oa,&maij->B);CHKERRQ(ierr);
5222 
5223   ierr = MatAssemblyBegin(maij->A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
5224   ierr = MatAssemblyEnd(maij->A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
5225   ierr = MatAssemblyBegin(maij->B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
5226   ierr = MatAssemblyEnd(maij->B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
5227 
5228   ierr = MatAssemblyBegin(*mat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
5229   ierr = MatAssemblyEnd(*mat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
5230   ierr = MatSetOption(*mat,MAT_NEW_NONZERO_LOCATION_ERR,PETSC_TRUE);CHKERRQ(ierr);
5231   PetscFunctionReturn(0);
5232 }
5233 
5234 /*
5235     Special version for direct calls from Fortran
5236 */
5237 #include <petsc-private/fortranimpl.h>
5238 
5239 #if defined(PETSC_HAVE_FORTRAN_CAPS)
5240 #define matsetvaluesmpiaij_ MATSETVALUESMPIAIJ
5241 #elif !defined(PETSC_HAVE_FORTRAN_UNDERSCORE)
5242 #define matsetvaluesmpiaij_ matsetvaluesmpiaij
5243 #endif
5244 
5245 /* Change these macros so can be used in void function */
5246 #undef CHKERRQ
5247 #define CHKERRQ(ierr) CHKERRABORT(PETSC_COMM_WORLD,ierr)
5248 #undef SETERRQ2
5249 #define SETERRQ2(comm,ierr,b,c,d) CHKERRABORT(comm,ierr)
5250 #undef SETERRQ3
5251 #define SETERRQ3(comm,ierr,b,c,d,e) CHKERRABORT(comm,ierr)
5252 #undef SETERRQ
5253 #define SETERRQ(c,ierr,b) CHKERRABORT(c,ierr)
5254 
5255 #undef __FUNCT__
5256 #define __FUNCT__ "matsetvaluesmpiaij_"
5257 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)
5258 {
5259   Mat            mat  = *mmat;
5260   PetscInt       m    = *mm, n = *mn;
5261   InsertMode     addv = *maddv;
5262   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
5263   PetscScalar    value;
5264   PetscErrorCode ierr;
5265 
5266   MatCheckPreallocated(mat,1);
5267   if (mat->insertmode == NOT_SET_VALUES) mat->insertmode = addv;
5268 
5269 #if defined(PETSC_USE_DEBUG)
5270   else if (mat->insertmode != addv) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"Cannot mix add values and insert values");
5271 #endif
5272   {
5273     PetscInt  i,j,rstart  = mat->rmap->rstart,rend = mat->rmap->rend;
5274     PetscInt  cstart      = mat->cmap->rstart,cend = mat->cmap->rend,row,col;
5275     PetscBool roworiented = aij->roworiented;
5276 
5277     /* Some Variables required in the macro */
5278     Mat        A                 = aij->A;
5279     Mat_SeqAIJ *a                = (Mat_SeqAIJ*)A->data;
5280     PetscInt   *aimax            = a->imax,*ai = a->i,*ailen = a->ilen,*aj = a->j;
5281     MatScalar  *aa               = a->a;
5282     PetscBool  ignorezeroentries = (((a->ignorezeroentries)&&(addv==ADD_VALUES)) ? PETSC_TRUE : PETSC_FALSE);
5283     Mat        B                 = aij->B;
5284     Mat_SeqAIJ *b                = (Mat_SeqAIJ*)B->data;
5285     PetscInt   *bimax            = b->imax,*bi = b->i,*bilen = b->ilen,*bj = b->j,bm = aij->B->rmap->n,am = aij->A->rmap->n;
5286     MatScalar  *ba               = b->a;
5287 
5288     PetscInt  *rp1,*rp2,ii,nrow1,nrow2,_i,rmax1,rmax2,N,low1,high1,low2,high2,t,lastcol1,lastcol2;
5289     PetscInt  nonew = a->nonew;
5290     MatScalar *ap1,*ap2;
5291 
5292     PetscFunctionBegin;
5293     for (i=0; i<m; i++) {
5294       if (im[i] < 0) continue;
5295 #if defined(PETSC_USE_DEBUG)
5296       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);
5297 #endif
5298       if (im[i] >= rstart && im[i] < rend) {
5299         row      = im[i] - rstart;
5300         lastcol1 = -1;
5301         rp1      = aj + ai[row];
5302         ap1      = aa + ai[row];
5303         rmax1    = aimax[row];
5304         nrow1    = ailen[row];
5305         low1     = 0;
5306         high1    = nrow1;
5307         lastcol2 = -1;
5308         rp2      = bj + bi[row];
5309         ap2      = ba + bi[row];
5310         rmax2    = bimax[row];
5311         nrow2    = bilen[row];
5312         low2     = 0;
5313         high2    = nrow2;
5314 
5315         for (j=0; j<n; j++) {
5316           if (roworiented) value = v[i*n+j];
5317           else value = v[i+j*m];
5318           if (ignorezeroentries && value == 0.0 && (addv == ADD_VALUES)) continue;
5319           if (in[j] >= cstart && in[j] < cend) {
5320             col = in[j] - cstart;
5321             MatSetValues_SeqAIJ_A_Private(row,col,value,addv,im[i],in[j]);
5322           } else if (in[j] < 0) continue;
5323 #if defined(PETSC_USE_DEBUG)
5324           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);
5325 #endif
5326           else {
5327             if (mat->was_assembled) {
5328               if (!aij->colmap) {
5329                 ierr = MatCreateColmap_MPIAIJ_Private(mat);CHKERRQ(ierr);
5330               }
5331 #if defined(PETSC_USE_CTABLE)
5332               ierr = PetscTableFind(aij->colmap,in[j]+1,&col);CHKERRQ(ierr);
5333               col--;
5334 #else
5335               col = aij->colmap[in[j]] - 1;
5336 #endif
5337               if (col < 0 && !((Mat_SeqAIJ*)(aij->A->data))->nonew) {
5338                 ierr = MatDisAssemble_MPIAIJ(mat);CHKERRQ(ierr);
5339                 col  =  in[j];
5340                 /* Reinitialize the variables required by MatSetValues_SeqAIJ_B_Private() */
5341                 B     = aij->B;
5342                 b     = (Mat_SeqAIJ*)B->data;
5343                 bimax = b->imax; bi = b->i; bilen = b->ilen; bj = b->j;
5344                 rp2   = bj + bi[row];
5345                 ap2   = ba + bi[row];
5346                 rmax2 = bimax[row];
5347                 nrow2 = bilen[row];
5348                 low2  = 0;
5349                 high2 = nrow2;
5350                 bm    = aij->B->rmap->n;
5351                 ba    = b->a;
5352               }
5353             } else col = in[j];
5354             MatSetValues_SeqAIJ_B_Private(row,col,value,addv,im[i],in[j]);
5355           }
5356         }
5357       } else if (!aij->donotstash) {
5358         if (roworiented) {
5359           ierr = MatStashValuesRow_Private(&mat->stash,im[i],n,in,v+i*n,(PetscBool)(ignorezeroentries && (addv == ADD_VALUES)));CHKERRQ(ierr);
5360         } else {
5361           ierr = MatStashValuesCol_Private(&mat->stash,im[i],n,in,v+i,m,(PetscBool)(ignorezeroentries && (addv == ADD_VALUES)));CHKERRQ(ierr);
5362         }
5363       }
5364     }
5365   }
5366   PetscFunctionReturnVoid();
5367 }
5368 
5369