xref: /petsc/src/mat/impls/aij/mpi/mpiaij.c (revision f9185b66528dabef5134ab6cdcf228fe8b971b0e)
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,MPI_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 #undef __FUNCT__
2638 #define __FUNCT__ "MatShift_MPIAIJ"
2639 PetscErrorCode MatShift_MPIAIJ(Mat Y,PetscScalar a)
2640 {
2641   PetscErrorCode ierr;
2642   Mat_MPIAIJ     *maij = (Mat_MPIAIJ*)Y->data;
2643   Mat_SeqAIJ     *aij = (Mat_SeqAIJ*)maij->A->data,*bij = (Mat_SeqAIJ*)maij->B->data;
2644 
2645   PetscFunctionBegin;
2646   if (!aij->nz && !bij->nz) {
2647     ierr = MatMPIAIJSetPreallocation(Y,1,NULL,0,NULL);CHKERRQ(ierr);
2648   }
2649   ierr = MatShift_Basic(Y,a);CHKERRQ(ierr);
2650   PetscFunctionReturn(0);
2651 }
2652 
2653 /* -------------------------------------------------------------------*/
2654 static struct _MatOps MatOps_Values = {MatSetValues_MPIAIJ,
2655                                        MatGetRow_MPIAIJ,
2656                                        MatRestoreRow_MPIAIJ,
2657                                        MatMult_MPIAIJ,
2658                                 /* 4*/ MatMultAdd_MPIAIJ,
2659                                        MatMultTranspose_MPIAIJ,
2660                                        MatMultTransposeAdd_MPIAIJ,
2661 #if defined(PETSC_HAVE_PBGL)
2662                                        MatSolve_MPIAIJ,
2663 #else
2664                                        0,
2665 #endif
2666                                        0,
2667                                        0,
2668                                 /*10*/ 0,
2669                                        0,
2670                                        0,
2671                                        MatSOR_MPIAIJ,
2672                                        MatTranspose_MPIAIJ,
2673                                 /*15*/ MatGetInfo_MPIAIJ,
2674                                        MatEqual_MPIAIJ,
2675                                        MatGetDiagonal_MPIAIJ,
2676                                        MatDiagonalScale_MPIAIJ,
2677                                        MatNorm_MPIAIJ,
2678                                 /*20*/ MatAssemblyBegin_MPIAIJ,
2679                                        MatAssemblyEnd_MPIAIJ,
2680                                        MatSetOption_MPIAIJ,
2681                                        MatZeroEntries_MPIAIJ,
2682                                 /*24*/ MatZeroRows_MPIAIJ,
2683                                        0,
2684 #if defined(PETSC_HAVE_PBGL)
2685                                        0,
2686 #else
2687                                        0,
2688 #endif
2689                                        0,
2690                                        0,
2691                                 /*29*/ MatSetUp_MPIAIJ,
2692 #if defined(PETSC_HAVE_PBGL)
2693                                        0,
2694 #else
2695                                        0,
2696 #endif
2697                                        0,
2698                                        0,
2699                                        0,
2700                                 /*34*/ MatDuplicate_MPIAIJ,
2701                                        0,
2702                                        0,
2703                                        0,
2704                                        0,
2705                                 /*39*/ MatAXPY_MPIAIJ,
2706                                        MatGetSubMatrices_MPIAIJ,
2707                                        MatIncreaseOverlap_MPIAIJ,
2708                                        MatGetValues_MPIAIJ,
2709                                        MatCopy_MPIAIJ,
2710                                 /*44*/ MatGetRowMax_MPIAIJ,
2711                                        MatScale_MPIAIJ,
2712                                        MatShift_MPIAIJ,
2713                                        MatDiagonalSet_MPIAIJ,
2714                                        MatZeroRowsColumns_MPIAIJ,
2715                                 /*49*/ MatSetRandom_MPIAIJ,
2716                                        0,
2717                                        0,
2718                                        0,
2719                                        0,
2720                                 /*54*/ MatFDColoringCreate_MPIXAIJ,
2721                                        0,
2722                                        MatSetUnfactored_MPIAIJ,
2723                                        MatPermute_MPIAIJ,
2724                                        0,
2725                                 /*59*/ MatGetSubMatrix_MPIAIJ,
2726                                        MatDestroy_MPIAIJ,
2727                                        MatView_MPIAIJ,
2728                                        0,
2729                                        MatMatMatMult_MPIAIJ_MPIAIJ_MPIAIJ,
2730                                 /*64*/ MatMatMatMultSymbolic_MPIAIJ_MPIAIJ_MPIAIJ,
2731                                        MatMatMatMultNumeric_MPIAIJ_MPIAIJ_MPIAIJ,
2732                                        0,
2733                                        0,
2734                                        0,
2735                                 /*69*/ MatGetRowMaxAbs_MPIAIJ,
2736                                        MatGetRowMinAbs_MPIAIJ,
2737                                        0,
2738                                        MatSetColoring_MPIAIJ,
2739                                        0,
2740                                        MatSetValuesAdifor_MPIAIJ,
2741                                 /*75*/ MatFDColoringApply_AIJ,
2742                                        MatSetFromOptions_MPIAIJ,
2743                                        0,
2744                                        0,
2745                                        MatFindZeroDiagonals_MPIAIJ,
2746                                 /*80*/ 0,
2747                                        0,
2748                                        0,
2749                                 /*83*/ MatLoad_MPIAIJ,
2750                                        0,
2751                                        0,
2752                                        0,
2753                                        0,
2754                                        0,
2755                                 /*89*/ MatMatMult_MPIAIJ_MPIAIJ,
2756                                        MatMatMultSymbolic_MPIAIJ_MPIAIJ,
2757                                        MatMatMultNumeric_MPIAIJ_MPIAIJ,
2758                                        MatPtAP_MPIAIJ_MPIAIJ,
2759                                        MatPtAPSymbolic_MPIAIJ_MPIAIJ,
2760                                 /*94*/ MatPtAPNumeric_MPIAIJ_MPIAIJ,
2761                                        0,
2762                                        0,
2763                                        0,
2764                                        0,
2765                                 /*99*/ 0,
2766                                        0,
2767                                        0,
2768                                        MatConjugate_MPIAIJ,
2769                                        0,
2770                                 /*104*/MatSetValuesRow_MPIAIJ,
2771                                        MatRealPart_MPIAIJ,
2772                                        MatImaginaryPart_MPIAIJ,
2773                                        0,
2774                                        0,
2775                                 /*109*/0,
2776                                        0,
2777                                        MatGetRowMin_MPIAIJ,
2778                                        0,
2779                                        0,
2780                                 /*114*/MatGetSeqNonzeroStructure_MPIAIJ,
2781                                        0,
2782                                        0,
2783                                        0,
2784                                        0,
2785                                 /*119*/0,
2786                                        0,
2787                                        0,
2788                                        0,
2789                                        MatGetMultiProcBlock_MPIAIJ,
2790                                 /*124*/MatFindNonzeroRows_MPIAIJ,
2791                                        MatGetColumnNorms_MPIAIJ,
2792                                        MatInvertBlockDiagonal_MPIAIJ,
2793                                        0,
2794                                        MatGetSubMatricesParallel_MPIAIJ,
2795                                 /*129*/0,
2796                                        MatTransposeMatMult_MPIAIJ_MPIAIJ,
2797                                        MatTransposeMatMultSymbolic_MPIAIJ_MPIAIJ,
2798                                        MatTransposeMatMultNumeric_MPIAIJ_MPIAIJ,
2799                                        0,
2800                                 /*134*/0,
2801                                        0,
2802                                        0,
2803                                        0,
2804                                        0,
2805                                 /*139*/0,
2806                                        0,
2807                                        0,
2808                                        MatFDColoringSetUp_MPIXAIJ,
2809                                        MatFindOffBlockDiagonalEntries_MPIAIJ,
2810                                 /*144*/MatCreateMPIMatConcatenateSeqMat_MPIAIJ
2811 };
2812 
2813 /* ----------------------------------------------------------------------------------------*/
2814 
2815 #undef __FUNCT__
2816 #define __FUNCT__ "MatStoreValues_MPIAIJ"
2817 PetscErrorCode  MatStoreValues_MPIAIJ(Mat mat)
2818 {
2819   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
2820   PetscErrorCode ierr;
2821 
2822   PetscFunctionBegin;
2823   ierr = MatStoreValues(aij->A);CHKERRQ(ierr);
2824   ierr = MatStoreValues(aij->B);CHKERRQ(ierr);
2825   PetscFunctionReturn(0);
2826 }
2827 
2828 #undef __FUNCT__
2829 #define __FUNCT__ "MatRetrieveValues_MPIAIJ"
2830 PetscErrorCode  MatRetrieveValues_MPIAIJ(Mat mat)
2831 {
2832   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
2833   PetscErrorCode ierr;
2834 
2835   PetscFunctionBegin;
2836   ierr = MatRetrieveValues(aij->A);CHKERRQ(ierr);
2837   ierr = MatRetrieveValues(aij->B);CHKERRQ(ierr);
2838   PetscFunctionReturn(0);
2839 }
2840 
2841 #undef __FUNCT__
2842 #define __FUNCT__ "MatMPIAIJSetPreallocation_MPIAIJ"
2843 PetscErrorCode  MatMPIAIJSetPreallocation_MPIAIJ(Mat B,PetscInt d_nz,const PetscInt d_nnz[],PetscInt o_nz,const PetscInt o_nnz[])
2844 {
2845   Mat_MPIAIJ     *b;
2846   PetscErrorCode ierr;
2847 
2848   PetscFunctionBegin;
2849   ierr = PetscLayoutSetUp(B->rmap);CHKERRQ(ierr);
2850   ierr = PetscLayoutSetUp(B->cmap);CHKERRQ(ierr);
2851   b = (Mat_MPIAIJ*)B->data;
2852 
2853   if (!B->preallocated) {
2854     /* Explicitly create 2 MATSEQAIJ matrices. */
2855     ierr = MatCreate(PETSC_COMM_SELF,&b->A);CHKERRQ(ierr);
2856     ierr = MatSetSizes(b->A,B->rmap->n,B->cmap->n,B->rmap->n,B->cmap->n);CHKERRQ(ierr);
2857     ierr = MatSetBlockSizesFromMats(b->A,B,B);CHKERRQ(ierr);
2858     ierr = MatSetType(b->A,MATSEQAIJ);CHKERRQ(ierr);
2859     ierr = PetscLogObjectParent((PetscObject)B,(PetscObject)b->A);CHKERRQ(ierr);
2860     ierr = MatCreate(PETSC_COMM_SELF,&b->B);CHKERRQ(ierr);
2861     ierr = MatSetSizes(b->B,B->rmap->n,B->cmap->N,B->rmap->n,B->cmap->N);CHKERRQ(ierr);
2862     ierr = MatSetBlockSizesFromMats(b->B,B,B);CHKERRQ(ierr);
2863     ierr = MatSetType(b->B,MATSEQAIJ);CHKERRQ(ierr);
2864     ierr = PetscLogObjectParent((PetscObject)B,(PetscObject)b->B);CHKERRQ(ierr);
2865   }
2866 
2867   ierr = MatSeqAIJSetPreallocation(b->A,d_nz,d_nnz);CHKERRQ(ierr);
2868   ierr = MatSeqAIJSetPreallocation(b->B,o_nz,o_nnz);CHKERRQ(ierr);
2869   B->preallocated = PETSC_TRUE;
2870   PetscFunctionReturn(0);
2871 }
2872 
2873 #undef __FUNCT__
2874 #define __FUNCT__ "MatDuplicate_MPIAIJ"
2875 PetscErrorCode MatDuplicate_MPIAIJ(Mat matin,MatDuplicateOption cpvalues,Mat *newmat)
2876 {
2877   Mat            mat;
2878   Mat_MPIAIJ     *a,*oldmat = (Mat_MPIAIJ*)matin->data;
2879   PetscErrorCode ierr;
2880 
2881   PetscFunctionBegin;
2882   *newmat = 0;
2883   ierr    = MatCreate(PetscObjectComm((PetscObject)matin),&mat);CHKERRQ(ierr);
2884   ierr    = MatSetSizes(mat,matin->rmap->n,matin->cmap->n,matin->rmap->N,matin->cmap->N);CHKERRQ(ierr);
2885   ierr    = MatSetBlockSizesFromMats(mat,matin,matin);CHKERRQ(ierr);
2886   ierr    = MatSetType(mat,((PetscObject)matin)->type_name);CHKERRQ(ierr);
2887   ierr    = PetscMemcpy(mat->ops,matin->ops,sizeof(struct _MatOps));CHKERRQ(ierr);
2888   a       = (Mat_MPIAIJ*)mat->data;
2889 
2890   mat->factortype   = matin->factortype;
2891   mat->assembled    = PETSC_TRUE;
2892   mat->insertmode   = NOT_SET_VALUES;
2893   mat->preallocated = PETSC_TRUE;
2894 
2895   a->size         = oldmat->size;
2896   a->rank         = oldmat->rank;
2897   a->donotstash   = oldmat->donotstash;
2898   a->roworiented  = oldmat->roworiented;
2899   a->rowindices   = 0;
2900   a->rowvalues    = 0;
2901   a->getrowactive = PETSC_FALSE;
2902 
2903   ierr = PetscLayoutReference(matin->rmap,&mat->rmap);CHKERRQ(ierr);
2904   ierr = PetscLayoutReference(matin->cmap,&mat->cmap);CHKERRQ(ierr);
2905 
2906   if (oldmat->colmap) {
2907 #if defined(PETSC_USE_CTABLE)
2908     ierr = PetscTableCreateCopy(oldmat->colmap,&a->colmap);CHKERRQ(ierr);
2909 #else
2910     ierr = PetscMalloc1(mat->cmap->N,&a->colmap);CHKERRQ(ierr);
2911     ierr = PetscLogObjectMemory((PetscObject)mat,(mat->cmap->N)*sizeof(PetscInt));CHKERRQ(ierr);
2912     ierr = PetscMemcpy(a->colmap,oldmat->colmap,(mat->cmap->N)*sizeof(PetscInt));CHKERRQ(ierr);
2913 #endif
2914   } else a->colmap = 0;
2915   if (oldmat->garray) {
2916     PetscInt len;
2917     len  = oldmat->B->cmap->n;
2918     ierr = PetscMalloc1(len+1,&a->garray);CHKERRQ(ierr);
2919     ierr = PetscLogObjectMemory((PetscObject)mat,len*sizeof(PetscInt));CHKERRQ(ierr);
2920     if (len) { ierr = PetscMemcpy(a->garray,oldmat->garray,len*sizeof(PetscInt));CHKERRQ(ierr); }
2921   } else a->garray = 0;
2922 
2923   ierr    = VecDuplicate(oldmat->lvec,&a->lvec);CHKERRQ(ierr);
2924   ierr    = PetscLogObjectParent((PetscObject)mat,(PetscObject)a->lvec);CHKERRQ(ierr);
2925   ierr    = VecScatterCopy(oldmat->Mvctx,&a->Mvctx);CHKERRQ(ierr);
2926   ierr    = PetscLogObjectParent((PetscObject)mat,(PetscObject)a->Mvctx);CHKERRQ(ierr);
2927   ierr    = MatDuplicate(oldmat->A,cpvalues,&a->A);CHKERRQ(ierr);
2928   ierr    = PetscLogObjectParent((PetscObject)mat,(PetscObject)a->A);CHKERRQ(ierr);
2929   ierr    = MatDuplicate(oldmat->B,cpvalues,&a->B);CHKERRQ(ierr);
2930   ierr    = PetscLogObjectParent((PetscObject)mat,(PetscObject)a->B);CHKERRQ(ierr);
2931   ierr    = PetscFunctionListDuplicate(((PetscObject)matin)->qlist,&((PetscObject)mat)->qlist);CHKERRQ(ierr);
2932   *newmat = mat;
2933   PetscFunctionReturn(0);
2934 }
2935 
2936 
2937 
2938 #undef __FUNCT__
2939 #define __FUNCT__ "MatLoad_MPIAIJ"
2940 PetscErrorCode MatLoad_MPIAIJ(Mat newMat, PetscViewer viewer)
2941 {
2942   PetscScalar    *vals,*svals;
2943   MPI_Comm       comm;
2944   PetscErrorCode ierr;
2945   PetscMPIInt    rank,size,tag = ((PetscObject)viewer)->tag;
2946   PetscInt       i,nz,j,rstart,rend,mmax,maxnz = 0;
2947   PetscInt       header[4],*rowlengths = 0,M,N,m,*cols;
2948   PetscInt       *ourlens = NULL,*procsnz = NULL,*offlens = NULL,jj,*mycols,*smycols;
2949   PetscInt       cend,cstart,n,*rowners;
2950   int            fd;
2951   PetscInt       bs = newMat->rmap->bs;
2952 
2953   PetscFunctionBegin;
2954   /* force binary viewer to load .info file if it has not yet done so */
2955   ierr = PetscViewerSetUp(viewer);CHKERRQ(ierr);
2956   ierr = PetscObjectGetComm((PetscObject)viewer,&comm);CHKERRQ(ierr);
2957   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
2958   ierr = MPI_Comm_rank(comm,&rank);CHKERRQ(ierr);
2959   ierr = PetscViewerBinaryGetDescriptor(viewer,&fd);CHKERRQ(ierr);
2960   if (!rank) {
2961     ierr = PetscBinaryRead(fd,(char*)header,4,PETSC_INT);CHKERRQ(ierr);
2962     if (header[0] != MAT_FILE_CLASSID) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_FILE_UNEXPECTED,"not matrix object");
2963   }
2964 
2965   ierr = PetscOptionsBegin(comm,NULL,"Options for loading MPIAIJ matrix","Mat");CHKERRQ(ierr);
2966   ierr = PetscOptionsInt("-matload_block_size","Set the blocksize used to store the matrix","MatLoad",bs,&bs,NULL);CHKERRQ(ierr);
2967   ierr = PetscOptionsEnd();CHKERRQ(ierr);
2968   if (bs < 0) bs = 1;
2969 
2970   ierr = MPI_Bcast(header+1,3,MPIU_INT,0,comm);CHKERRQ(ierr);
2971   M    = header[1]; N = header[2];
2972 
2973   /* If global sizes are set, check if they are consistent with that given in the file */
2974   if (newMat->rmap->N >= 0 && newMat->rmap->N != M) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_FILE_UNEXPECTED,"Inconsistent # of rows:Matrix in file has (%D) and input matrix has (%D)",newMat->rmap->N,M);
2975   if (newMat->cmap->N >=0 && newMat->cmap->N != N) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_FILE_UNEXPECTED,"Inconsistent # of cols:Matrix in file has (%D) and input matrix has (%D)",newMat->cmap->N,N);
2976 
2977   /* determine ownership of all (block) rows */
2978   if (M%bs) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_FILE_UNEXPECTED, "Inconsistent # of rows (%d) and block size (%d)",M,bs);
2979   if (newMat->rmap->n < 0) m = bs*((M/bs)/size + (((M/bs) % size) > rank));    /* PETSC_DECIDE */
2980   else m = newMat->rmap->n; /* Set by user */
2981 
2982   ierr = PetscMalloc1(size+1,&rowners);CHKERRQ(ierr);
2983   ierr = MPI_Allgather(&m,1,MPIU_INT,rowners+1,1,MPIU_INT,comm);CHKERRQ(ierr);
2984 
2985   /* First process needs enough room for process with most rows */
2986   if (!rank) {
2987     mmax = rowners[1];
2988     for (i=2; i<=size; i++) {
2989       mmax = PetscMax(mmax, rowners[i]);
2990     }
2991   } else mmax = -1;             /* unused, but compilers complain */
2992 
2993   rowners[0] = 0;
2994   for (i=2; i<=size; i++) {
2995     rowners[i] += rowners[i-1];
2996   }
2997   rstart = rowners[rank];
2998   rend   = rowners[rank+1];
2999 
3000   /* distribute row lengths to all processors */
3001   ierr = PetscMalloc2(m,&ourlens,m,&offlens);CHKERRQ(ierr);
3002   if (!rank) {
3003     ierr = PetscBinaryRead(fd,ourlens,m,PETSC_INT);CHKERRQ(ierr);
3004     ierr = PetscMalloc1(mmax,&rowlengths);CHKERRQ(ierr);
3005     ierr = PetscCalloc1(size,&procsnz);CHKERRQ(ierr);
3006     for (j=0; j<m; j++) {
3007       procsnz[0] += ourlens[j];
3008     }
3009     for (i=1; i<size; i++) {
3010       ierr = PetscBinaryRead(fd,rowlengths,rowners[i+1]-rowners[i],PETSC_INT);CHKERRQ(ierr);
3011       /* calculate the number of nonzeros on each processor */
3012       for (j=0; j<rowners[i+1]-rowners[i]; j++) {
3013         procsnz[i] += rowlengths[j];
3014       }
3015       ierr = MPIULong_Send(rowlengths,rowners[i+1]-rowners[i],MPIU_INT,i,tag,comm);CHKERRQ(ierr);
3016     }
3017     ierr = PetscFree(rowlengths);CHKERRQ(ierr);
3018   } else {
3019     ierr = MPIULong_Recv(ourlens,m,MPIU_INT,0,tag,comm);CHKERRQ(ierr);
3020   }
3021 
3022   if (!rank) {
3023     /* determine max buffer needed and allocate it */
3024     maxnz = 0;
3025     for (i=0; i<size; i++) {
3026       maxnz = PetscMax(maxnz,procsnz[i]);
3027     }
3028     ierr = PetscMalloc1(maxnz,&cols);CHKERRQ(ierr);
3029 
3030     /* read in my part of the matrix column indices  */
3031     nz   = procsnz[0];
3032     ierr = PetscMalloc1(nz,&mycols);CHKERRQ(ierr);
3033     ierr = PetscBinaryRead(fd,mycols,nz,PETSC_INT);CHKERRQ(ierr);
3034 
3035     /* read in every one elses and ship off */
3036     for (i=1; i<size; i++) {
3037       nz   = procsnz[i];
3038       ierr = PetscBinaryRead(fd,cols,nz,PETSC_INT);CHKERRQ(ierr);
3039       ierr = MPIULong_Send(cols,nz,MPIU_INT,i,tag,comm);CHKERRQ(ierr);
3040     }
3041     ierr = PetscFree(cols);CHKERRQ(ierr);
3042   } else {
3043     /* determine buffer space needed for message */
3044     nz = 0;
3045     for (i=0; i<m; i++) {
3046       nz += ourlens[i];
3047     }
3048     ierr = PetscMalloc1(nz,&mycols);CHKERRQ(ierr);
3049 
3050     /* receive message of column indices*/
3051     ierr = MPIULong_Recv(mycols,nz,MPIU_INT,0,tag,comm);CHKERRQ(ierr);
3052   }
3053 
3054   /* determine column ownership if matrix is not square */
3055   if (N != M) {
3056     if (newMat->cmap->n < 0) n = N/size + ((N % size) > rank);
3057     else n = newMat->cmap->n;
3058     ierr   = MPI_Scan(&n,&cend,1,MPIU_INT,MPI_SUM,comm);CHKERRQ(ierr);
3059     cstart = cend - n;
3060   } else {
3061     cstart = rstart;
3062     cend   = rend;
3063     n      = cend - cstart;
3064   }
3065 
3066   /* loop over local rows, determining number of off diagonal entries */
3067   ierr = PetscMemzero(offlens,m*sizeof(PetscInt));CHKERRQ(ierr);
3068   jj   = 0;
3069   for (i=0; i<m; i++) {
3070     for (j=0; j<ourlens[i]; j++) {
3071       if (mycols[jj] < cstart || mycols[jj] >= cend) offlens[i]++;
3072       jj++;
3073     }
3074   }
3075 
3076   for (i=0; i<m; i++) {
3077     ourlens[i] -= offlens[i];
3078   }
3079   ierr = MatSetSizes(newMat,m,n,M,N);CHKERRQ(ierr);
3080 
3081   if (bs > 1) {ierr = MatSetBlockSize(newMat,bs);CHKERRQ(ierr);}
3082 
3083   ierr = MatMPIAIJSetPreallocation(newMat,0,ourlens,0,offlens);CHKERRQ(ierr);
3084 
3085   for (i=0; i<m; i++) {
3086     ourlens[i] += offlens[i];
3087   }
3088 
3089   if (!rank) {
3090     ierr = PetscMalloc1(maxnz+1,&vals);CHKERRQ(ierr);
3091 
3092     /* read in my part of the matrix numerical values  */
3093     nz   = procsnz[0];
3094     ierr = PetscBinaryRead(fd,vals,nz,PETSC_SCALAR);CHKERRQ(ierr);
3095 
3096     /* insert into matrix */
3097     jj      = rstart;
3098     smycols = mycols;
3099     svals   = vals;
3100     for (i=0; i<m; i++) {
3101       ierr     = MatSetValues_MPIAIJ(newMat,1,&jj,ourlens[i],smycols,svals,INSERT_VALUES);CHKERRQ(ierr);
3102       smycols += ourlens[i];
3103       svals   += ourlens[i];
3104       jj++;
3105     }
3106 
3107     /* read in other processors and ship out */
3108     for (i=1; i<size; i++) {
3109       nz   = procsnz[i];
3110       ierr = PetscBinaryRead(fd,vals,nz,PETSC_SCALAR);CHKERRQ(ierr);
3111       ierr = MPIULong_Send(vals,nz,MPIU_SCALAR,i,((PetscObject)newMat)->tag,comm);CHKERRQ(ierr);
3112     }
3113     ierr = PetscFree(procsnz);CHKERRQ(ierr);
3114   } else {
3115     /* receive numeric values */
3116     ierr = PetscMalloc1(nz+1,&vals);CHKERRQ(ierr);
3117 
3118     /* receive message of values*/
3119     ierr = MPIULong_Recv(vals,nz,MPIU_SCALAR,0,((PetscObject)newMat)->tag,comm);CHKERRQ(ierr);
3120 
3121     /* insert into matrix */
3122     jj      = rstart;
3123     smycols = mycols;
3124     svals   = vals;
3125     for (i=0; i<m; i++) {
3126       ierr     = MatSetValues_MPIAIJ(newMat,1,&jj,ourlens[i],smycols,svals,INSERT_VALUES);CHKERRQ(ierr);
3127       smycols += ourlens[i];
3128       svals   += ourlens[i];
3129       jj++;
3130     }
3131   }
3132   ierr = PetscFree2(ourlens,offlens);CHKERRQ(ierr);
3133   ierr = PetscFree(vals);CHKERRQ(ierr);
3134   ierr = PetscFree(mycols);CHKERRQ(ierr);
3135   ierr = PetscFree(rowners);CHKERRQ(ierr);
3136   ierr = MatAssemblyBegin(newMat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
3137   ierr = MatAssemblyEnd(newMat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
3138   PetscFunctionReturn(0);
3139 }
3140 
3141 #undef __FUNCT__
3142 #define __FUNCT__ "MatGetSubMatrix_MPIAIJ"
3143 PetscErrorCode MatGetSubMatrix_MPIAIJ(Mat mat,IS isrow,IS iscol,MatReuse call,Mat *newmat)
3144 {
3145   PetscErrorCode ierr;
3146   IS             iscol_local;
3147   PetscInt       csize;
3148 
3149   PetscFunctionBegin;
3150   ierr = ISGetLocalSize(iscol,&csize);CHKERRQ(ierr);
3151   if (call == MAT_REUSE_MATRIX) {
3152     ierr = PetscObjectQuery((PetscObject)*newmat,"ISAllGather",(PetscObject*)&iscol_local);CHKERRQ(ierr);
3153     if (!iscol_local) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"Submatrix passed in was not used before, cannot reuse");
3154   } else {
3155     PetscInt cbs;
3156     ierr = ISGetBlockSize(iscol,&cbs);CHKERRQ(ierr);
3157     ierr = ISAllGather(iscol,&iscol_local);CHKERRQ(ierr);
3158     ierr = ISSetBlockSize(iscol_local,cbs);CHKERRQ(ierr);
3159   }
3160   ierr = MatGetSubMatrix_MPIAIJ_Private(mat,isrow,iscol_local,csize,call,newmat);CHKERRQ(ierr);
3161   if (call == MAT_INITIAL_MATRIX) {
3162     ierr = PetscObjectCompose((PetscObject)*newmat,"ISAllGather",(PetscObject)iscol_local);CHKERRQ(ierr);
3163     ierr = ISDestroy(&iscol_local);CHKERRQ(ierr);
3164   }
3165   PetscFunctionReturn(0);
3166 }
3167 
3168 extern PetscErrorCode MatGetSubMatrices_MPIAIJ_Local(Mat,PetscInt,const IS[],const IS[],MatReuse,PetscBool*,Mat*);
3169 #undef __FUNCT__
3170 #define __FUNCT__ "MatGetSubMatrix_MPIAIJ_Private"
3171 /*
3172     Not great since it makes two copies of the submatrix, first an SeqAIJ
3173   in local and then by concatenating the local matrices the end result.
3174   Writing it directly would be much like MatGetSubMatrices_MPIAIJ()
3175 
3176   Note: This requires a sequential iscol with all indices.
3177 */
3178 PetscErrorCode MatGetSubMatrix_MPIAIJ_Private(Mat mat,IS isrow,IS iscol,PetscInt csize,MatReuse call,Mat *newmat)
3179 {
3180   PetscErrorCode ierr;
3181   PetscMPIInt    rank,size;
3182   PetscInt       i,m,n,rstart,row,rend,nz,*cwork,j,bs,cbs;
3183   PetscInt       *ii,*jj,nlocal,*dlens,*olens,dlen,olen,jend,mglobal,ncol;
3184   PetscBool      allcolumns, colflag;
3185   Mat            M,Mreuse;
3186   MatScalar      *vwork,*aa;
3187   MPI_Comm       comm;
3188   Mat_SeqAIJ     *aij;
3189 
3190   PetscFunctionBegin;
3191   ierr = PetscObjectGetComm((PetscObject)mat,&comm);CHKERRQ(ierr);
3192   ierr = MPI_Comm_rank(comm,&rank);CHKERRQ(ierr);
3193   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
3194 
3195   ierr = ISIdentity(iscol,&colflag);CHKERRQ(ierr);
3196   ierr = ISGetLocalSize(iscol,&ncol);CHKERRQ(ierr);
3197   if (colflag && ncol == mat->cmap->N) {
3198     allcolumns = PETSC_TRUE;
3199   } else {
3200     allcolumns = PETSC_FALSE;
3201   }
3202   if (call ==  MAT_REUSE_MATRIX) {
3203     ierr = PetscObjectQuery((PetscObject)*newmat,"SubMatrix",(PetscObject*)&Mreuse);CHKERRQ(ierr);
3204     if (!Mreuse) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"Submatrix passed in was not used before, cannot reuse");
3205     ierr = MatGetSubMatrices_MPIAIJ_Local(mat,1,&isrow,&iscol,MAT_REUSE_MATRIX,&allcolumns,&Mreuse);CHKERRQ(ierr);
3206   } else {
3207     ierr = MatGetSubMatrices_MPIAIJ_Local(mat,1,&isrow,&iscol,MAT_INITIAL_MATRIX,&allcolumns,&Mreuse);CHKERRQ(ierr);
3208   }
3209 
3210   /*
3211       m - number of local rows
3212       n - number of columns (same on all processors)
3213       rstart - first row in new global matrix generated
3214   */
3215   ierr = MatGetSize(Mreuse,&m,&n);CHKERRQ(ierr);
3216   ierr = MatGetBlockSizes(Mreuse,&bs,&cbs);CHKERRQ(ierr);
3217   if (call == MAT_INITIAL_MATRIX) {
3218     aij = (Mat_SeqAIJ*)(Mreuse)->data;
3219     ii  = aij->i;
3220     jj  = aij->j;
3221 
3222     /*
3223         Determine the number of non-zeros in the diagonal and off-diagonal
3224         portions of the matrix in order to do correct preallocation
3225     */
3226 
3227     /* first get start and end of "diagonal" columns */
3228     if (csize == PETSC_DECIDE) {
3229       ierr = ISGetSize(isrow,&mglobal);CHKERRQ(ierr);
3230       if (mglobal == n) { /* square matrix */
3231         nlocal = m;
3232       } else {
3233         nlocal = n/size + ((n % size) > rank);
3234       }
3235     } else {
3236       nlocal = csize;
3237     }
3238     ierr   = MPI_Scan(&nlocal,&rend,1,MPIU_INT,MPI_SUM,comm);CHKERRQ(ierr);
3239     rstart = rend - nlocal;
3240     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);
3241 
3242     /* next, compute all the lengths */
3243     ierr  = PetscMalloc1(2*m+1,&dlens);CHKERRQ(ierr);
3244     olens = dlens + m;
3245     for (i=0; i<m; i++) {
3246       jend = ii[i+1] - ii[i];
3247       olen = 0;
3248       dlen = 0;
3249       for (j=0; j<jend; j++) {
3250         if (*jj < rstart || *jj >= rend) olen++;
3251         else dlen++;
3252         jj++;
3253       }
3254       olens[i] = olen;
3255       dlens[i] = dlen;
3256     }
3257     ierr = MatCreate(comm,&M);CHKERRQ(ierr);
3258     ierr = MatSetSizes(M,m,nlocal,PETSC_DECIDE,n);CHKERRQ(ierr);
3259     ierr = MatSetBlockSizes(M,bs,cbs);CHKERRQ(ierr);
3260     ierr = MatSetType(M,((PetscObject)mat)->type_name);CHKERRQ(ierr);
3261     ierr = MatMPIAIJSetPreallocation(M,0,dlens,0,olens);CHKERRQ(ierr);
3262     ierr = PetscFree(dlens);CHKERRQ(ierr);
3263   } else {
3264     PetscInt ml,nl;
3265 
3266     M    = *newmat;
3267     ierr = MatGetLocalSize(M,&ml,&nl);CHKERRQ(ierr);
3268     if (ml != m) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_SIZ,"Previous matrix must be same size/layout as request");
3269     ierr = MatZeroEntries(M);CHKERRQ(ierr);
3270     /*
3271          The next two lines are needed so we may call MatSetValues_MPIAIJ() below directly,
3272        rather than the slower MatSetValues().
3273     */
3274     M->was_assembled = PETSC_TRUE;
3275     M->assembled     = PETSC_FALSE;
3276   }
3277   ierr = MatGetOwnershipRange(M,&rstart,&rend);CHKERRQ(ierr);
3278   aij  = (Mat_SeqAIJ*)(Mreuse)->data;
3279   ii   = aij->i;
3280   jj   = aij->j;
3281   aa   = aij->a;
3282   for (i=0; i<m; i++) {
3283     row   = rstart + i;
3284     nz    = ii[i+1] - ii[i];
3285     cwork = jj;     jj += nz;
3286     vwork = aa;     aa += nz;
3287     ierr  = MatSetValues_MPIAIJ(M,1,&row,nz,cwork,vwork,INSERT_VALUES);CHKERRQ(ierr);
3288   }
3289 
3290   ierr    = MatAssemblyBegin(M,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
3291   ierr    = MatAssemblyEnd(M,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
3292   *newmat = M;
3293 
3294   /* save submatrix used in processor for next request */
3295   if (call ==  MAT_INITIAL_MATRIX) {
3296     ierr = PetscObjectCompose((PetscObject)M,"SubMatrix",(PetscObject)Mreuse);CHKERRQ(ierr);
3297     ierr = MatDestroy(&Mreuse);CHKERRQ(ierr);
3298   }
3299   PetscFunctionReturn(0);
3300 }
3301 
3302 #undef __FUNCT__
3303 #define __FUNCT__ "MatMPIAIJSetPreallocationCSR_MPIAIJ"
3304 PetscErrorCode  MatMPIAIJSetPreallocationCSR_MPIAIJ(Mat B,const PetscInt Ii[],const PetscInt J[],const PetscScalar v[])
3305 {
3306   PetscInt       m,cstart, cend,j,nnz,i,d;
3307   PetscInt       *d_nnz,*o_nnz,nnz_max = 0,rstart,ii;
3308   const PetscInt *JJ;
3309   PetscScalar    *values;
3310   PetscErrorCode ierr;
3311 
3312   PetscFunctionBegin;
3313   if (Ii[0]) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Ii[0] must be 0 it is %D",Ii[0]);
3314 
3315   ierr   = PetscLayoutSetUp(B->rmap);CHKERRQ(ierr);
3316   ierr   = PetscLayoutSetUp(B->cmap);CHKERRQ(ierr);
3317   m      = B->rmap->n;
3318   cstart = B->cmap->rstart;
3319   cend   = B->cmap->rend;
3320   rstart = B->rmap->rstart;
3321 
3322   ierr = PetscMalloc2(m,&d_nnz,m,&o_nnz);CHKERRQ(ierr);
3323 
3324 #if defined(PETSC_USE_DEBUGGING)
3325   for (i=0; i<m; i++) {
3326     nnz = Ii[i+1]- Ii[i];
3327     JJ  = J + Ii[i];
3328     if (nnz < 0) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Local row %D has a negative %D number of columns",i,nnz);
3329     if (nnz && (JJ[0] < 0)) SETERRRQ1(PETSC_ERR_ARG_WRONGSTATE,"Row %D starts with negative column index",i,j);
3330     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);
3331   }
3332 #endif
3333 
3334   for (i=0; i<m; i++) {
3335     nnz     = Ii[i+1]- Ii[i];
3336     JJ      = J + Ii[i];
3337     nnz_max = PetscMax(nnz_max,nnz);
3338     d       = 0;
3339     for (j=0; j<nnz; j++) {
3340       if (cstart <= JJ[j] && JJ[j] < cend) d++;
3341     }
3342     d_nnz[i] = d;
3343     o_nnz[i] = nnz - d;
3344   }
3345   ierr = MatMPIAIJSetPreallocation(B,0,d_nnz,0,o_nnz);CHKERRQ(ierr);
3346   ierr = PetscFree2(d_nnz,o_nnz);CHKERRQ(ierr);
3347 
3348   if (v) values = (PetscScalar*)v;
3349   else {
3350     ierr = PetscCalloc1(nnz_max+1,&values);CHKERRQ(ierr);
3351   }
3352 
3353   for (i=0; i<m; i++) {
3354     ii   = i + rstart;
3355     nnz  = Ii[i+1]- Ii[i];
3356     ierr = MatSetValues_MPIAIJ(B,1,&ii,nnz,J+Ii[i],values+(v ? Ii[i] : 0),INSERT_VALUES);CHKERRQ(ierr);
3357   }
3358   ierr = MatAssemblyBegin(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
3359   ierr = MatAssemblyEnd(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
3360 
3361   if (!v) {
3362     ierr = PetscFree(values);CHKERRQ(ierr);
3363   }
3364   ierr = MatSetOption(B,MAT_NEW_NONZERO_LOCATION_ERR,PETSC_TRUE);CHKERRQ(ierr);
3365   PetscFunctionReturn(0);
3366 }
3367 
3368 #undef __FUNCT__
3369 #define __FUNCT__ "MatMPIAIJSetPreallocationCSR"
3370 /*@
3371    MatMPIAIJSetPreallocationCSR - Allocates memory for a sparse parallel matrix in AIJ format
3372    (the default parallel PETSc format).
3373 
3374    Collective on MPI_Comm
3375 
3376    Input Parameters:
3377 +  B - the matrix
3378 .  i - the indices into j for the start of each local row (starts with zero)
3379 .  j - the column indices for each local row (starts with zero)
3380 -  v - optional values in the matrix
3381 
3382    Level: developer
3383 
3384    Notes:
3385        The i, j, and a arrays ARE copied by this routine into the internal format used by PETSc;
3386      thus you CANNOT change the matrix entries by changing the values of a[] after you have
3387      called this routine. Use MatCreateMPIAIJWithSplitArrays() to avoid needing to copy the arrays.
3388 
3389        The i and j indices are 0 based, and i indices are indices corresponding to the local j array.
3390 
3391        The format which is used for the sparse matrix input, is equivalent to a
3392     row-major ordering.. i.e for the following matrix, the input data expected is
3393     as shown:
3394 
3395         1 0 0
3396         2 0 3     P0
3397        -------
3398         4 5 6     P1
3399 
3400      Process0 [P0]: rows_owned=[0,1]
3401         i =  {0,1,3}  [size = nrow+1  = 2+1]
3402         j =  {0,0,2}  [size = nz = 6]
3403         v =  {1,2,3}  [size = nz = 6]
3404 
3405      Process1 [P1]: rows_owned=[2]
3406         i =  {0,3}    [size = nrow+1  = 1+1]
3407         j =  {0,1,2}  [size = nz = 6]
3408         v =  {4,5,6}  [size = nz = 6]
3409 
3410 .keywords: matrix, aij, compressed row, sparse, parallel
3411 
3412 .seealso: MatCreate(), MatCreateSeqAIJ(), MatSetValues(), MatMPIAIJSetPreallocation(), MatCreateAIJ(), MPIAIJ,
3413           MatCreateSeqAIJWithArrays(), MatCreateMPIAIJWithSplitArrays()
3414 @*/
3415 PetscErrorCode  MatMPIAIJSetPreallocationCSR(Mat B,const PetscInt i[],const PetscInt j[], const PetscScalar v[])
3416 {
3417   PetscErrorCode ierr;
3418 
3419   PetscFunctionBegin;
3420   ierr = PetscTryMethod(B,"MatMPIAIJSetPreallocationCSR_C",(Mat,const PetscInt[],const PetscInt[],const PetscScalar[]),(B,i,j,v));CHKERRQ(ierr);
3421   PetscFunctionReturn(0);
3422 }
3423 
3424 #undef __FUNCT__
3425 #define __FUNCT__ "MatMPIAIJSetPreallocation"
3426 /*@C
3427    MatMPIAIJSetPreallocation - Preallocates memory for a sparse parallel matrix in AIJ format
3428    (the default parallel PETSc format).  For good matrix assembly performance
3429    the user should preallocate the matrix storage by setting the parameters
3430    d_nz (or d_nnz) and o_nz (or o_nnz).  By setting these parameters accurately,
3431    performance can be increased by more than a factor of 50.
3432 
3433    Collective on MPI_Comm
3434 
3435    Input Parameters:
3436 +  B - the matrix
3437 .  d_nz  - number of nonzeros per row in DIAGONAL portion of local submatrix
3438            (same value is used for all local rows)
3439 .  d_nnz - array containing the number of nonzeros in the various rows of the
3440            DIAGONAL portion of the local submatrix (possibly different for each row)
3441            or NULL, if d_nz is used to specify the nonzero structure.
3442            The size of this array is equal to the number of local rows, i.e 'm'.
3443            For matrices that will be factored, you must leave room for (and set)
3444            the diagonal entry even if it is zero.
3445 .  o_nz  - number of nonzeros per row in the OFF-DIAGONAL portion of local
3446            submatrix (same value is used for all local rows).
3447 -  o_nnz - array containing the number of nonzeros in the various rows of the
3448            OFF-DIAGONAL portion of the local submatrix (possibly different for
3449            each row) or NULL, if o_nz is used to specify the nonzero
3450            structure. The size of this array is equal to the number
3451            of local rows, i.e 'm'.
3452 
3453    If the *_nnz parameter is given then the *_nz parameter is ignored
3454 
3455    The AIJ format (also called the Yale sparse matrix format or
3456    compressed row storage (CSR)), is fully compatible with standard Fortran 77
3457    storage.  The stored row and column indices begin with zero.
3458    See Users-Manual: ch_mat for details.
3459 
3460    The parallel matrix is partitioned such that the first m0 rows belong to
3461    process 0, the next m1 rows belong to process 1, the next m2 rows belong
3462    to process 2 etc.. where m0,m1,m2... are the input parameter 'm'.
3463 
3464    The DIAGONAL portion of the local submatrix of a processor can be defined
3465    as the submatrix which is obtained by extraction the part corresponding to
3466    the rows r1-r2 and columns c1-c2 of the global matrix, where r1 is the
3467    first row that belongs to the processor, r2 is the last row belonging to
3468    the this processor, and c1-c2 is range of indices of the local part of a
3469    vector suitable for applying the matrix to.  This is an mxn matrix.  In the
3470    common case of a square matrix, the row and column ranges are the same and
3471    the DIAGONAL part is also square. The remaining portion of the local
3472    submatrix (mxN) constitute the OFF-DIAGONAL portion.
3473 
3474    If o_nnz, d_nnz are specified, then o_nz, and d_nz are ignored.
3475 
3476    You can call MatGetInfo() to get information on how effective the preallocation was;
3477    for example the fields mallocs,nz_allocated,nz_used,nz_unneeded;
3478    You can also run with the option -info and look for messages with the string
3479    malloc in them to see if additional memory allocation was needed.
3480 
3481    Example usage:
3482 
3483    Consider the following 8x8 matrix with 34 non-zero values, that is
3484    assembled across 3 processors. Lets assume that proc0 owns 3 rows,
3485    proc1 owns 3 rows, proc2 owns 2 rows. This division can be shown
3486    as follows:
3487 
3488 .vb
3489             1  2  0  |  0  3  0  |  0  4
3490     Proc0   0  5  6  |  7  0  0  |  8  0
3491             9  0 10  | 11  0  0  | 12  0
3492     -------------------------------------
3493            13  0 14  | 15 16 17  |  0  0
3494     Proc1   0 18  0  | 19 20 21  |  0  0
3495             0  0  0  | 22 23  0  | 24  0
3496     -------------------------------------
3497     Proc2  25 26 27  |  0  0 28  | 29  0
3498            30  0  0  | 31 32 33  |  0 34
3499 .ve
3500 
3501    This can be represented as a collection of submatrices as:
3502 
3503 .vb
3504       A B C
3505       D E F
3506       G H I
3507 .ve
3508 
3509    Where the submatrices A,B,C are owned by proc0, D,E,F are
3510    owned by proc1, G,H,I are owned by proc2.
3511 
3512    The 'm' parameters for proc0,proc1,proc2 are 3,3,2 respectively.
3513    The 'n' parameters for proc0,proc1,proc2 are 3,3,2 respectively.
3514    The 'M','N' parameters are 8,8, and have the same values on all procs.
3515 
3516    The DIAGONAL submatrices corresponding to proc0,proc1,proc2 are
3517    submatrices [A], [E], [I] respectively. The OFF-DIAGONAL submatrices
3518    corresponding to proc0,proc1,proc2 are [BC], [DF], [GH] respectively.
3519    Internally, each processor stores the DIAGONAL part, and the OFF-DIAGONAL
3520    part as SeqAIJ matrices. for eg: proc1 will store [E] as a SeqAIJ
3521    matrix, ans [DF] as another SeqAIJ matrix.
3522 
3523    When d_nz, o_nz parameters are specified, d_nz storage elements are
3524    allocated for every row of the local diagonal submatrix, and o_nz
3525    storage locations are allocated for every row of the OFF-DIAGONAL submat.
3526    One way to choose d_nz and o_nz is to use the max nonzerors per local
3527    rows for each of the local DIAGONAL, and the OFF-DIAGONAL submatrices.
3528    In this case, the values of d_nz,o_nz are:
3529 .vb
3530      proc0 : dnz = 2, o_nz = 2
3531      proc1 : dnz = 3, o_nz = 2
3532      proc2 : dnz = 1, o_nz = 4
3533 .ve
3534    We are allocating m*(d_nz+o_nz) storage locations for every proc. This
3535    translates to 3*(2+2)=12 for proc0, 3*(3+2)=15 for proc1, 2*(1+4)=10
3536    for proc3. i.e we are using 12+15+10=37 storage locations to store
3537    34 values.
3538 
3539    When d_nnz, o_nnz parameters are specified, the storage is specified
3540    for every row, coresponding to both DIAGONAL and OFF-DIAGONAL submatrices.
3541    In the above case the values for d_nnz,o_nnz are:
3542 .vb
3543      proc0: d_nnz = [2,2,2] and o_nnz = [2,2,2]
3544      proc1: d_nnz = [3,3,2] and o_nnz = [2,1,1]
3545      proc2: d_nnz = [1,1]   and o_nnz = [4,4]
3546 .ve
3547    Here the space allocated is sum of all the above values i.e 34, and
3548    hence pre-allocation is perfect.
3549 
3550    Level: intermediate
3551 
3552 .keywords: matrix, aij, compressed row, sparse, parallel
3553 
3554 .seealso: MatCreate(), MatCreateSeqAIJ(), MatSetValues(), MatCreateAIJ(), MatMPIAIJSetPreallocationCSR(),
3555           MPIAIJ, MatGetInfo(), PetscSplitOwnership()
3556 @*/
3557 PetscErrorCode  MatMPIAIJSetPreallocation(Mat B,PetscInt d_nz,const PetscInt d_nnz[],PetscInt o_nz,const PetscInt o_nnz[])
3558 {
3559   PetscErrorCode ierr;
3560 
3561   PetscFunctionBegin;
3562   PetscValidHeaderSpecific(B,MAT_CLASSID,1);
3563   PetscValidType(B,1);
3564   ierr = PetscTryMethod(B,"MatMPIAIJSetPreallocation_C",(Mat,PetscInt,const PetscInt[],PetscInt,const PetscInt[]),(B,d_nz,d_nnz,o_nz,o_nnz));CHKERRQ(ierr);
3565   PetscFunctionReturn(0);
3566 }
3567 
3568 #undef __FUNCT__
3569 #define __FUNCT__ "MatCreateMPIAIJWithArrays"
3570 /*@
3571      MatCreateMPIAIJWithArrays - creates a MPI AIJ matrix using arrays that contain in standard
3572          CSR format the local rows.
3573 
3574    Collective on MPI_Comm
3575 
3576    Input Parameters:
3577 +  comm - MPI communicator
3578 .  m - number of local rows (Cannot be PETSC_DECIDE)
3579 .  n - This value should be the same as the local size used in creating the
3580        x vector for the matrix-vector product y = Ax. (or PETSC_DECIDE to have
3581        calculated if N is given) For square matrices n is almost always m.
3582 .  M - number of global rows (or PETSC_DETERMINE to have calculated if m is given)
3583 .  N - number of global columns (or PETSC_DETERMINE to have calculated if n is given)
3584 .   i - row indices
3585 .   j - column indices
3586 -   a - matrix values
3587 
3588    Output Parameter:
3589 .   mat - the matrix
3590 
3591    Level: intermediate
3592 
3593    Notes:
3594        The i, j, and a arrays ARE copied by this routine into the internal format used by PETSc;
3595      thus you CANNOT change the matrix entries by changing the values of a[] after you have
3596      called this routine. Use MatCreateMPIAIJWithSplitArrays() to avoid needing to copy the arrays.
3597 
3598        The i and j indices are 0 based, and i indices are indices corresponding to the local j array.
3599 
3600        The format which is used for the sparse matrix input, is equivalent to a
3601     row-major ordering.. i.e for the following matrix, the input data expected is
3602     as shown:
3603 
3604         1 0 0
3605         2 0 3     P0
3606        -------
3607         4 5 6     P1
3608 
3609      Process0 [P0]: rows_owned=[0,1]
3610         i =  {0,1,3}  [size = nrow+1  = 2+1]
3611         j =  {0,0,2}  [size = nz = 6]
3612         v =  {1,2,3}  [size = nz = 6]
3613 
3614      Process1 [P1]: rows_owned=[2]
3615         i =  {0,3}    [size = nrow+1  = 1+1]
3616         j =  {0,1,2}  [size = nz = 6]
3617         v =  {4,5,6}  [size = nz = 6]
3618 
3619 .keywords: matrix, aij, compressed row, sparse, parallel
3620 
3621 .seealso: MatCreate(), MatCreateSeqAIJ(), MatSetValues(), MatMPIAIJSetPreallocation(), MatMPIAIJSetPreallocationCSR(),
3622           MPIAIJ, MatCreateAIJ(), MatCreateMPIAIJWithSplitArrays()
3623 @*/
3624 PetscErrorCode  MatCreateMPIAIJWithArrays(MPI_Comm comm,PetscInt m,PetscInt n,PetscInt M,PetscInt N,const PetscInt i[],const PetscInt j[],const PetscScalar a[],Mat *mat)
3625 {
3626   PetscErrorCode ierr;
3627 
3628   PetscFunctionBegin;
3629   if (i[0]) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"i (row indices) must start with 0");
3630   if (m < 0) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"local number of rows (m) cannot be PETSC_DECIDE, or negative");
3631   ierr = MatCreate(comm,mat);CHKERRQ(ierr);
3632   ierr = MatSetSizes(*mat,m,n,M,N);CHKERRQ(ierr);
3633   /* ierr = MatSetBlockSizes(M,bs,cbs);CHKERRQ(ierr); */
3634   ierr = MatSetType(*mat,MATMPIAIJ);CHKERRQ(ierr);
3635   ierr = MatMPIAIJSetPreallocationCSR(*mat,i,j,a);CHKERRQ(ierr);
3636   PetscFunctionReturn(0);
3637 }
3638 
3639 #undef __FUNCT__
3640 #define __FUNCT__ "MatCreateAIJ"
3641 /*@C
3642    MatCreateAIJ - Creates a sparse parallel matrix in AIJ format
3643    (the default parallel PETSc format).  For good matrix assembly performance
3644    the user should preallocate the matrix storage by setting the parameters
3645    d_nz (or d_nnz) and o_nz (or o_nnz).  By setting these parameters accurately,
3646    performance can be increased by more than a factor of 50.
3647 
3648    Collective on MPI_Comm
3649 
3650    Input Parameters:
3651 +  comm - MPI communicator
3652 .  m - number of local rows (or PETSC_DECIDE to have calculated if M is given)
3653            This value should be the same as the local size used in creating the
3654            y vector for the matrix-vector product y = Ax.
3655 .  n - This value should be the same as the local size used in creating the
3656        x vector for the matrix-vector product y = Ax. (or PETSC_DECIDE to have
3657        calculated if N is given) For square matrices n is almost always m.
3658 .  M - number of global rows (or PETSC_DETERMINE to have calculated if m is given)
3659 .  N - number of global columns (or PETSC_DETERMINE to have calculated if n is given)
3660 .  d_nz  - number of nonzeros per row in DIAGONAL portion of local submatrix
3661            (same value is used for all local rows)
3662 .  d_nnz - array containing the number of nonzeros in the various rows of the
3663            DIAGONAL portion of the local submatrix (possibly different for each row)
3664            or NULL, if d_nz is used to specify the nonzero structure.
3665            The size of this array is equal to the number of local rows, i.e 'm'.
3666 .  o_nz  - number of nonzeros per row in the OFF-DIAGONAL portion of local
3667            submatrix (same value is used for all local rows).
3668 -  o_nnz - array containing the number of nonzeros in the various rows of the
3669            OFF-DIAGONAL portion of the local submatrix (possibly different for
3670            each row) or NULL, if o_nz is used to specify the nonzero
3671            structure. The size of this array is equal to the number
3672            of local rows, i.e 'm'.
3673 
3674    Output Parameter:
3675 .  A - the matrix
3676 
3677    It is recommended that one use the MatCreate(), MatSetType() and/or MatSetFromOptions(),
3678    MatXXXXSetPreallocation() paradgm instead of this routine directly.
3679    [MatXXXXSetPreallocation() is, for example, MatSeqAIJSetPreallocation]
3680 
3681    Notes:
3682    If the *_nnz parameter is given then the *_nz parameter is ignored
3683 
3684    m,n,M,N parameters specify the size of the matrix, and its partitioning across
3685    processors, while d_nz,d_nnz,o_nz,o_nnz parameters specify the approximate
3686    storage requirements for this matrix.
3687 
3688    If PETSC_DECIDE or  PETSC_DETERMINE is used for a particular argument on one
3689    processor than it must be used on all processors that share the object for
3690    that argument.
3691 
3692    The user MUST specify either the local or global matrix dimensions
3693    (possibly both).
3694 
3695    The parallel matrix is partitioned across processors such that the
3696    first m0 rows belong to process 0, the next m1 rows belong to
3697    process 1, the next m2 rows belong to process 2 etc.. where
3698    m0,m1,m2,.. are the input parameter 'm'. i.e each processor stores
3699    values corresponding to [m x N] submatrix.
3700 
3701    The columns are logically partitioned with the n0 columns belonging
3702    to 0th partition, the next n1 columns belonging to the next
3703    partition etc.. where n0,n1,n2... are the input parameter 'n'.
3704 
3705    The DIAGONAL portion of the local submatrix on any given processor
3706    is the submatrix corresponding to the rows and columns m,n
3707    corresponding to the given processor. i.e diagonal matrix on
3708    process 0 is [m0 x n0], diagonal matrix on process 1 is [m1 x n1]
3709    etc. The remaining portion of the local submatrix [m x (N-n)]
3710    constitute the OFF-DIAGONAL portion. The example below better
3711    illustrates this concept.
3712 
3713    For a square global matrix we define each processor's diagonal portion
3714    to be its local rows and the corresponding columns (a square submatrix);
3715    each processor's off-diagonal portion encompasses the remainder of the
3716    local matrix (a rectangular submatrix).
3717 
3718    If o_nnz, d_nnz are specified, then o_nz, and d_nz are ignored.
3719 
3720    When calling this routine with a single process communicator, a matrix of
3721    type SEQAIJ is returned.  If a matrix of type MPIAIJ is desired for this
3722    type of communicator, use the construction mechanism:
3723      MatCreate(...,&A); MatSetType(A,MATMPIAIJ); MatSetSizes(A, m,n,M,N); MatMPIAIJSetPreallocation(A,...);
3724 
3725    By default, this format uses inodes (identical nodes) when possible.
3726    We search for consecutive rows with the same nonzero structure, thereby
3727    reusing matrix information to achieve increased efficiency.
3728 
3729    Options Database Keys:
3730 +  -mat_no_inode  - Do not use inodes
3731 .  -mat_inode_limit <limit> - Sets inode limit (max limit=5)
3732 -  -mat_aij_oneindex - Internally use indexing starting at 1
3733         rather than 0.  Note that when calling MatSetValues(),
3734         the user still MUST index entries starting at 0!
3735 
3736 
3737    Example usage:
3738 
3739    Consider the following 8x8 matrix with 34 non-zero values, that is
3740    assembled across 3 processors. Lets assume that proc0 owns 3 rows,
3741    proc1 owns 3 rows, proc2 owns 2 rows. This division can be shown
3742    as follows:
3743 
3744 .vb
3745             1  2  0  |  0  3  0  |  0  4
3746     Proc0   0  5  6  |  7  0  0  |  8  0
3747             9  0 10  | 11  0  0  | 12  0
3748     -------------------------------------
3749            13  0 14  | 15 16 17  |  0  0
3750     Proc1   0 18  0  | 19 20 21  |  0  0
3751             0  0  0  | 22 23  0  | 24  0
3752     -------------------------------------
3753     Proc2  25 26 27  |  0  0 28  | 29  0
3754            30  0  0  | 31 32 33  |  0 34
3755 .ve
3756 
3757    This can be represented as a collection of submatrices as:
3758 
3759 .vb
3760       A B C
3761       D E F
3762       G H I
3763 .ve
3764 
3765    Where the submatrices A,B,C are owned by proc0, D,E,F are
3766    owned by proc1, G,H,I are owned by proc2.
3767 
3768    The 'm' parameters for proc0,proc1,proc2 are 3,3,2 respectively.
3769    The 'n' parameters for proc0,proc1,proc2 are 3,3,2 respectively.
3770    The 'M','N' parameters are 8,8, and have the same values on all procs.
3771 
3772    The DIAGONAL submatrices corresponding to proc0,proc1,proc2 are
3773    submatrices [A], [E], [I] respectively. The OFF-DIAGONAL submatrices
3774    corresponding to proc0,proc1,proc2 are [BC], [DF], [GH] respectively.
3775    Internally, each processor stores the DIAGONAL part, and the OFF-DIAGONAL
3776    part as SeqAIJ matrices. for eg: proc1 will store [E] as a SeqAIJ
3777    matrix, ans [DF] as another SeqAIJ matrix.
3778 
3779    When d_nz, o_nz parameters are specified, d_nz storage elements are
3780    allocated for every row of the local diagonal submatrix, and o_nz
3781    storage locations are allocated for every row of the OFF-DIAGONAL submat.
3782    One way to choose d_nz and o_nz is to use the max nonzerors per local
3783    rows for each of the local DIAGONAL, and the OFF-DIAGONAL submatrices.
3784    In this case, the values of d_nz,o_nz are:
3785 .vb
3786      proc0 : dnz = 2, o_nz = 2
3787      proc1 : dnz = 3, o_nz = 2
3788      proc2 : dnz = 1, o_nz = 4
3789 .ve
3790    We are allocating m*(d_nz+o_nz) storage locations for every proc. This
3791    translates to 3*(2+2)=12 for proc0, 3*(3+2)=15 for proc1, 2*(1+4)=10
3792    for proc3. i.e we are using 12+15+10=37 storage locations to store
3793    34 values.
3794 
3795    When d_nnz, o_nnz parameters are specified, the storage is specified
3796    for every row, coresponding to both DIAGONAL and OFF-DIAGONAL submatrices.
3797    In the above case the values for d_nnz,o_nnz are:
3798 .vb
3799      proc0: d_nnz = [2,2,2] and o_nnz = [2,2,2]
3800      proc1: d_nnz = [3,3,2] and o_nnz = [2,1,1]
3801      proc2: d_nnz = [1,1]   and o_nnz = [4,4]
3802 .ve
3803    Here the space allocated is sum of all the above values i.e 34, and
3804    hence pre-allocation is perfect.
3805 
3806    Level: intermediate
3807 
3808 .keywords: matrix, aij, compressed row, sparse, parallel
3809 
3810 .seealso: MatCreate(), MatCreateSeqAIJ(), MatSetValues(), MatMPIAIJSetPreallocation(), MatMPIAIJSetPreallocationCSR(),
3811           MPIAIJ, MatCreateMPIAIJWithArrays()
3812 @*/
3813 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)
3814 {
3815   PetscErrorCode ierr;
3816   PetscMPIInt    size;
3817 
3818   PetscFunctionBegin;
3819   ierr = MatCreate(comm,A);CHKERRQ(ierr);
3820   ierr = MatSetSizes(*A,m,n,M,N);CHKERRQ(ierr);
3821   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
3822   if (size > 1) {
3823     ierr = MatSetType(*A,MATMPIAIJ);CHKERRQ(ierr);
3824     ierr = MatMPIAIJSetPreallocation(*A,d_nz,d_nnz,o_nz,o_nnz);CHKERRQ(ierr);
3825   } else {
3826     ierr = MatSetType(*A,MATSEQAIJ);CHKERRQ(ierr);
3827     ierr = MatSeqAIJSetPreallocation(*A,d_nz,d_nnz);CHKERRQ(ierr);
3828   }
3829   PetscFunctionReturn(0);
3830 }
3831 
3832 #undef __FUNCT__
3833 #define __FUNCT__ "MatMPIAIJGetSeqAIJ"
3834 PetscErrorCode  MatMPIAIJGetSeqAIJ(Mat A,Mat *Ad,Mat *Ao,const PetscInt *colmap[])
3835 {
3836   Mat_MPIAIJ *a = (Mat_MPIAIJ*)A->data;
3837 
3838   PetscFunctionBegin;
3839   if (Ad)     *Ad     = a->A;
3840   if (Ao)     *Ao     = a->B;
3841   if (colmap) *colmap = a->garray;
3842   PetscFunctionReturn(0);
3843 }
3844 
3845 #undef __FUNCT__
3846 #define __FUNCT__ "MatSetColoring_MPIAIJ"
3847 PetscErrorCode MatSetColoring_MPIAIJ(Mat A,ISColoring coloring)
3848 {
3849   PetscErrorCode ierr;
3850   PetscInt       i;
3851   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
3852 
3853   PetscFunctionBegin;
3854   if (coloring->ctype == IS_COLORING_GLOBAL) {
3855     ISColoringValue *allcolors,*colors;
3856     ISColoring      ocoloring;
3857 
3858     /* set coloring for diagonal portion */
3859     ierr = MatSetColoring_SeqAIJ(a->A,coloring);CHKERRQ(ierr);
3860 
3861     /* set coloring for off-diagonal portion */
3862     ierr = ISAllGatherColors(PetscObjectComm((PetscObject)A),coloring->n,coloring->colors,NULL,&allcolors);CHKERRQ(ierr);
3863     ierr = PetscMalloc1(a->B->cmap->n+1,&colors);CHKERRQ(ierr);
3864     for (i=0; i<a->B->cmap->n; i++) {
3865       colors[i] = allcolors[a->garray[i]];
3866     }
3867     ierr = PetscFree(allcolors);CHKERRQ(ierr);
3868     ierr = ISColoringCreate(MPI_COMM_SELF,coloring->n,a->B->cmap->n,colors,PETSC_OWN_POINTER,&ocoloring);CHKERRQ(ierr);
3869     ierr = MatSetColoring_SeqAIJ(a->B,ocoloring);CHKERRQ(ierr);
3870     ierr = ISColoringDestroy(&ocoloring);CHKERRQ(ierr);
3871   } else if (coloring->ctype == IS_COLORING_GHOSTED) {
3872     ISColoringValue *colors;
3873     PetscInt        *larray;
3874     ISColoring      ocoloring;
3875 
3876     /* set coloring for diagonal portion */
3877     ierr = PetscMalloc1(a->A->cmap->n+1,&larray);CHKERRQ(ierr);
3878     for (i=0; i<a->A->cmap->n; i++) {
3879       larray[i] = i + A->cmap->rstart;
3880     }
3881     ierr = ISGlobalToLocalMappingApply(A->cmap->mapping,IS_GTOLM_MASK,a->A->cmap->n,larray,NULL,larray);CHKERRQ(ierr);
3882     ierr = PetscMalloc1(a->A->cmap->n+1,&colors);CHKERRQ(ierr);
3883     for (i=0; i<a->A->cmap->n; i++) {
3884       colors[i] = coloring->colors[larray[i]];
3885     }
3886     ierr = PetscFree(larray);CHKERRQ(ierr);
3887     ierr = ISColoringCreate(PETSC_COMM_SELF,coloring->n,a->A->cmap->n,colors,PETSC_OWN_POINTER,&ocoloring);CHKERRQ(ierr);
3888     ierr = MatSetColoring_SeqAIJ(a->A,ocoloring);CHKERRQ(ierr);
3889     ierr = ISColoringDestroy(&ocoloring);CHKERRQ(ierr);
3890 
3891     /* set coloring for off-diagonal portion */
3892     ierr = PetscMalloc1(a->B->cmap->n+1,&larray);CHKERRQ(ierr);
3893     ierr = ISGlobalToLocalMappingApply(A->cmap->mapping,IS_GTOLM_MASK,a->B->cmap->n,a->garray,NULL,larray);CHKERRQ(ierr);
3894     ierr = PetscMalloc1(a->B->cmap->n+1,&colors);CHKERRQ(ierr);
3895     for (i=0; i<a->B->cmap->n; i++) {
3896       colors[i] = coloring->colors[larray[i]];
3897     }
3898     ierr = PetscFree(larray);CHKERRQ(ierr);
3899     ierr = ISColoringCreate(MPI_COMM_SELF,coloring->n,a->B->cmap->n,colors,PETSC_OWN_POINTER,&ocoloring);CHKERRQ(ierr);
3900     ierr = MatSetColoring_SeqAIJ(a->B,ocoloring);CHKERRQ(ierr);
3901     ierr = ISColoringDestroy(&ocoloring);CHKERRQ(ierr);
3902   } else SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_SUP,"No support ISColoringType %d",(int)coloring->ctype);
3903   PetscFunctionReturn(0);
3904 }
3905 
3906 #undef __FUNCT__
3907 #define __FUNCT__ "MatSetValuesAdifor_MPIAIJ"
3908 PetscErrorCode MatSetValuesAdifor_MPIAIJ(Mat A,PetscInt nl,void *advalues)
3909 {
3910   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
3911   PetscErrorCode ierr;
3912 
3913   PetscFunctionBegin;
3914   ierr = MatSetValuesAdifor_SeqAIJ(a->A,nl,advalues);CHKERRQ(ierr);
3915   ierr = MatSetValuesAdifor_SeqAIJ(a->B,nl,advalues);CHKERRQ(ierr);
3916   PetscFunctionReturn(0);
3917 }
3918 
3919 #undef __FUNCT__
3920 #define __FUNCT__ "MatCreateMPIMatConcatenateSeqMat_MPIAIJ"
3921 PetscErrorCode MatCreateMPIMatConcatenateSeqMat_MPIAIJ(MPI_Comm comm,Mat inmat,PetscInt n,MatReuse scall,Mat *outmat)
3922 {
3923   PetscErrorCode ierr;
3924   PetscInt       m,N,i,rstart,nnz,Ii;
3925   PetscInt       *indx;
3926   PetscScalar    *values;
3927 
3928   PetscFunctionBegin;
3929   ierr = MatGetSize(inmat,&m,&N);CHKERRQ(ierr);
3930   if (scall == MAT_INITIAL_MATRIX) { /* symbolic phase */
3931     PetscInt       *dnz,*onz,sum,bs,cbs;
3932 
3933     if (n == PETSC_DECIDE) {
3934       ierr = PetscSplitOwnership(comm,&n,&N);CHKERRQ(ierr);
3935     }
3936     /* Check sum(n) = N */
3937     ierr = MPI_Allreduce(&n,&sum,1,MPIU_INT,MPI_SUM,comm);CHKERRQ(ierr);
3938     if (sum != N) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_INCOMP,"Sum of local columns != global columns %d",N);
3939 
3940     ierr    = MPI_Scan(&m, &rstart,1,MPIU_INT,MPI_SUM,comm);CHKERRQ(ierr);
3941     rstart -= m;
3942 
3943     ierr = MatPreallocateInitialize(comm,m,n,dnz,onz);CHKERRQ(ierr);
3944     for (i=0; i<m; i++) {
3945       ierr = MatGetRow_SeqAIJ(inmat,i,&nnz,&indx,NULL);CHKERRQ(ierr);
3946       ierr = MatPreallocateSet(i+rstart,nnz,indx,dnz,onz);CHKERRQ(ierr);
3947       ierr = MatRestoreRow_SeqAIJ(inmat,i,&nnz,&indx,NULL);CHKERRQ(ierr);
3948     }
3949 
3950     ierr = MatCreate(comm,outmat);CHKERRQ(ierr);
3951     ierr = MatSetSizes(*outmat,m,n,PETSC_DETERMINE,PETSC_DETERMINE);CHKERRQ(ierr);
3952     ierr = MatGetBlockSizes(inmat,&bs,&cbs);CHKERRQ(ierr);
3953     ierr = MatSetBlockSizes(*outmat,bs,cbs);CHKERRQ(ierr);
3954     ierr = MatSetType(*outmat,MATMPIAIJ);CHKERRQ(ierr);
3955     ierr = MatMPIAIJSetPreallocation(*outmat,0,dnz,0,onz);CHKERRQ(ierr);
3956     ierr = MatPreallocateFinalize(dnz,onz);CHKERRQ(ierr);
3957   }
3958 
3959   /* numeric phase */
3960   ierr = MatGetOwnershipRange(*outmat,&rstart,NULL);CHKERRQ(ierr);
3961   for (i=0; i<m; i++) {
3962     ierr = MatGetRow_SeqAIJ(inmat,i,&nnz,&indx,&values);CHKERRQ(ierr);
3963     Ii   = i + rstart;
3964     ierr = MatSetValues(*outmat,1,&Ii,nnz,indx,values,INSERT_VALUES);CHKERRQ(ierr);
3965     ierr = MatRestoreRow_SeqAIJ(inmat,i,&nnz,&indx,&values);CHKERRQ(ierr);
3966   }
3967   ierr = MatAssemblyBegin(*outmat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
3968   ierr = MatAssemblyEnd(*outmat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
3969   PetscFunctionReturn(0);
3970 }
3971 
3972 #undef __FUNCT__
3973 #define __FUNCT__ "MatFileSplit"
3974 PetscErrorCode MatFileSplit(Mat A,char *outfile)
3975 {
3976   PetscErrorCode    ierr;
3977   PetscMPIInt       rank;
3978   PetscInt          m,N,i,rstart,nnz;
3979   size_t            len;
3980   const PetscInt    *indx;
3981   PetscViewer       out;
3982   char              *name;
3983   Mat               B;
3984   const PetscScalar *values;
3985 
3986   PetscFunctionBegin;
3987   ierr = MatGetLocalSize(A,&m,0);CHKERRQ(ierr);
3988   ierr = MatGetSize(A,0,&N);CHKERRQ(ierr);
3989   /* Should this be the type of the diagonal block of A? */
3990   ierr = MatCreate(PETSC_COMM_SELF,&B);CHKERRQ(ierr);
3991   ierr = MatSetSizes(B,m,N,m,N);CHKERRQ(ierr);
3992   ierr = MatSetBlockSizesFromMats(B,A,A);CHKERRQ(ierr);
3993   ierr = MatSetType(B,MATSEQAIJ);CHKERRQ(ierr);
3994   ierr = MatSeqAIJSetPreallocation(B,0,NULL);CHKERRQ(ierr);
3995   ierr = MatGetOwnershipRange(A,&rstart,0);CHKERRQ(ierr);
3996   for (i=0; i<m; i++) {
3997     ierr = MatGetRow(A,i+rstart,&nnz,&indx,&values);CHKERRQ(ierr);
3998     ierr = MatSetValues(B,1,&i,nnz,indx,values,INSERT_VALUES);CHKERRQ(ierr);
3999     ierr = MatRestoreRow(A,i+rstart,&nnz,&indx,&values);CHKERRQ(ierr);
4000   }
4001   ierr = MatAssemblyBegin(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
4002   ierr = MatAssemblyEnd(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
4003 
4004   ierr = MPI_Comm_rank(PetscObjectComm((PetscObject)A),&rank);CHKERRQ(ierr);
4005   ierr = PetscStrlen(outfile,&len);CHKERRQ(ierr);
4006   ierr = PetscMalloc1(len+5,&name);CHKERRQ(ierr);
4007   sprintf(name,"%s.%d",outfile,rank);
4008   ierr = PetscViewerBinaryOpen(PETSC_COMM_SELF,name,FILE_MODE_APPEND,&out);CHKERRQ(ierr);
4009   ierr = PetscFree(name);CHKERRQ(ierr);
4010   ierr = MatView(B,out);CHKERRQ(ierr);
4011   ierr = PetscViewerDestroy(&out);CHKERRQ(ierr);
4012   ierr = MatDestroy(&B);CHKERRQ(ierr);
4013   PetscFunctionReturn(0);
4014 }
4015 
4016 extern PetscErrorCode MatDestroy_MPIAIJ(Mat);
4017 #undef __FUNCT__
4018 #define __FUNCT__ "MatDestroy_MPIAIJ_SeqsToMPI"
4019 PetscErrorCode  MatDestroy_MPIAIJ_SeqsToMPI(Mat A)
4020 {
4021   PetscErrorCode      ierr;
4022   Mat_Merge_SeqsToMPI *merge;
4023   PetscContainer      container;
4024 
4025   PetscFunctionBegin;
4026   ierr = PetscObjectQuery((PetscObject)A,"MatMergeSeqsToMPI",(PetscObject*)&container);CHKERRQ(ierr);
4027   if (container) {
4028     ierr = PetscContainerGetPointer(container,(void**)&merge);CHKERRQ(ierr);
4029     ierr = PetscFree(merge->id_r);CHKERRQ(ierr);
4030     ierr = PetscFree(merge->len_s);CHKERRQ(ierr);
4031     ierr = PetscFree(merge->len_r);CHKERRQ(ierr);
4032     ierr = PetscFree(merge->bi);CHKERRQ(ierr);
4033     ierr = PetscFree(merge->bj);CHKERRQ(ierr);
4034     ierr = PetscFree(merge->buf_ri[0]);CHKERRQ(ierr);
4035     ierr = PetscFree(merge->buf_ri);CHKERRQ(ierr);
4036     ierr = PetscFree(merge->buf_rj[0]);CHKERRQ(ierr);
4037     ierr = PetscFree(merge->buf_rj);CHKERRQ(ierr);
4038     ierr = PetscFree(merge->coi);CHKERRQ(ierr);
4039     ierr = PetscFree(merge->coj);CHKERRQ(ierr);
4040     ierr = PetscFree(merge->owners_co);CHKERRQ(ierr);
4041     ierr = PetscLayoutDestroy(&merge->rowmap);CHKERRQ(ierr);
4042     ierr = PetscFree(merge);CHKERRQ(ierr);
4043     ierr = PetscObjectCompose((PetscObject)A,"MatMergeSeqsToMPI",0);CHKERRQ(ierr);
4044   }
4045   ierr = MatDestroy_MPIAIJ(A);CHKERRQ(ierr);
4046   PetscFunctionReturn(0);
4047 }
4048 
4049 #include <../src/mat/utils/freespace.h>
4050 #include <petscbt.h>
4051 
4052 #undef __FUNCT__
4053 #define __FUNCT__ "MatCreateMPIAIJSumSeqAIJNumeric"
4054 PetscErrorCode  MatCreateMPIAIJSumSeqAIJNumeric(Mat seqmat,Mat mpimat)
4055 {
4056   PetscErrorCode      ierr;
4057   MPI_Comm            comm;
4058   Mat_SeqAIJ          *a  =(Mat_SeqAIJ*)seqmat->data;
4059   PetscMPIInt         size,rank,taga,*len_s;
4060   PetscInt            N=mpimat->cmap->N,i,j,*owners,*ai=a->i,*aj;
4061   PetscInt            proc,m;
4062   PetscInt            **buf_ri,**buf_rj;
4063   PetscInt            k,anzi,*bj_i,*bi,*bj,arow,bnzi,nextaj;
4064   PetscInt            nrows,**buf_ri_k,**nextrow,**nextai;
4065   MPI_Request         *s_waits,*r_waits;
4066   MPI_Status          *status;
4067   MatScalar           *aa=a->a;
4068   MatScalar           **abuf_r,*ba_i;
4069   Mat_Merge_SeqsToMPI *merge;
4070   PetscContainer      container;
4071 
4072   PetscFunctionBegin;
4073   ierr = PetscObjectGetComm((PetscObject)mpimat,&comm);CHKERRQ(ierr);
4074   ierr = PetscLogEventBegin(MAT_Seqstompinum,seqmat,0,0,0);CHKERRQ(ierr);
4075 
4076   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
4077   ierr = MPI_Comm_rank(comm,&rank);CHKERRQ(ierr);
4078 
4079   ierr = PetscObjectQuery((PetscObject)mpimat,"MatMergeSeqsToMPI",(PetscObject*)&container);CHKERRQ(ierr);
4080   ierr = PetscContainerGetPointer(container,(void**)&merge);CHKERRQ(ierr);
4081 
4082   bi     = merge->bi;
4083   bj     = merge->bj;
4084   buf_ri = merge->buf_ri;
4085   buf_rj = merge->buf_rj;
4086 
4087   ierr   = PetscMalloc1(size,&status);CHKERRQ(ierr);
4088   owners = merge->rowmap->range;
4089   len_s  = merge->len_s;
4090 
4091   /* send and recv matrix values */
4092   /*-----------------------------*/
4093   ierr = PetscObjectGetNewTag((PetscObject)mpimat,&taga);CHKERRQ(ierr);
4094   ierr = PetscPostIrecvScalar(comm,taga,merge->nrecv,merge->id_r,merge->len_r,&abuf_r,&r_waits);CHKERRQ(ierr);
4095 
4096   ierr = PetscMalloc1(merge->nsend+1,&s_waits);CHKERRQ(ierr);
4097   for (proc=0,k=0; proc<size; proc++) {
4098     if (!len_s[proc]) continue;
4099     i    = owners[proc];
4100     ierr = MPI_Isend(aa+ai[i],len_s[proc],MPIU_MATSCALAR,proc,taga,comm,s_waits+k);CHKERRQ(ierr);
4101     k++;
4102   }
4103 
4104   if (merge->nrecv) {ierr = MPI_Waitall(merge->nrecv,r_waits,status);CHKERRQ(ierr);}
4105   if (merge->nsend) {ierr = MPI_Waitall(merge->nsend,s_waits,status);CHKERRQ(ierr);}
4106   ierr = PetscFree(status);CHKERRQ(ierr);
4107 
4108   ierr = PetscFree(s_waits);CHKERRQ(ierr);
4109   ierr = PetscFree(r_waits);CHKERRQ(ierr);
4110 
4111   /* insert mat values of mpimat */
4112   /*----------------------------*/
4113   ierr = PetscMalloc1(N,&ba_i);CHKERRQ(ierr);
4114   ierr = PetscMalloc3(merge->nrecv,&buf_ri_k,merge->nrecv,&nextrow,merge->nrecv,&nextai);CHKERRQ(ierr);
4115 
4116   for (k=0; k<merge->nrecv; k++) {
4117     buf_ri_k[k] = buf_ri[k]; /* beginning of k-th recved i-structure */
4118     nrows       = *(buf_ri_k[k]);
4119     nextrow[k]  = buf_ri_k[k]+1;  /* next row number of k-th recved i-structure */
4120     nextai[k]   = buf_ri_k[k] + (nrows + 1); /* poins to the next i-structure of k-th recved i-structure  */
4121   }
4122 
4123   /* set values of ba */
4124   m = merge->rowmap->n;
4125   for (i=0; i<m; i++) {
4126     arow = owners[rank] + i;
4127     bj_i = bj+bi[i];  /* col indices of the i-th row of mpimat */
4128     bnzi = bi[i+1] - bi[i];
4129     ierr = PetscMemzero(ba_i,bnzi*sizeof(PetscScalar));CHKERRQ(ierr);
4130 
4131     /* add local non-zero vals of this proc's seqmat into ba */
4132     anzi   = ai[arow+1] - ai[arow];
4133     aj     = a->j + ai[arow];
4134     aa     = a->a + ai[arow];
4135     nextaj = 0;
4136     for (j=0; nextaj<anzi; j++) {
4137       if (*(bj_i + j) == aj[nextaj]) { /* bcol == acol */
4138         ba_i[j] += aa[nextaj++];
4139       }
4140     }
4141 
4142     /* add received vals into ba */
4143     for (k=0; k<merge->nrecv; k++) { /* k-th received message */
4144       /* i-th row */
4145       if (i == *nextrow[k]) {
4146         anzi   = *(nextai[k]+1) - *nextai[k];
4147         aj     = buf_rj[k] + *(nextai[k]);
4148         aa     = abuf_r[k] + *(nextai[k]);
4149         nextaj = 0;
4150         for (j=0; nextaj<anzi; j++) {
4151           if (*(bj_i + j) == aj[nextaj]) { /* bcol == acol */
4152             ba_i[j] += aa[nextaj++];
4153           }
4154         }
4155         nextrow[k]++; nextai[k]++;
4156       }
4157     }
4158     ierr = MatSetValues(mpimat,1,&arow,bnzi,bj_i,ba_i,INSERT_VALUES);CHKERRQ(ierr);
4159   }
4160   ierr = MatAssemblyBegin(mpimat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
4161   ierr = MatAssemblyEnd(mpimat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
4162 
4163   ierr = PetscFree(abuf_r[0]);CHKERRQ(ierr);
4164   ierr = PetscFree(abuf_r);CHKERRQ(ierr);
4165   ierr = PetscFree(ba_i);CHKERRQ(ierr);
4166   ierr = PetscFree3(buf_ri_k,nextrow,nextai);CHKERRQ(ierr);
4167   ierr = PetscLogEventEnd(MAT_Seqstompinum,seqmat,0,0,0);CHKERRQ(ierr);
4168   PetscFunctionReturn(0);
4169 }
4170 
4171 extern PetscErrorCode  MatDestroy_MPIAIJ_SeqsToMPI(Mat);
4172 
4173 #undef __FUNCT__
4174 #define __FUNCT__ "MatCreateMPIAIJSumSeqAIJSymbolic"
4175 PetscErrorCode  MatCreateMPIAIJSumSeqAIJSymbolic(MPI_Comm comm,Mat seqmat,PetscInt m,PetscInt n,Mat *mpimat)
4176 {
4177   PetscErrorCode      ierr;
4178   Mat                 B_mpi;
4179   Mat_SeqAIJ          *a=(Mat_SeqAIJ*)seqmat->data;
4180   PetscMPIInt         size,rank,tagi,tagj,*len_s,*len_si,*len_ri;
4181   PetscInt            **buf_rj,**buf_ri,**buf_ri_k;
4182   PetscInt            M=seqmat->rmap->n,N=seqmat->cmap->n,i,*owners,*ai=a->i,*aj=a->j;
4183   PetscInt            len,proc,*dnz,*onz,bs,cbs;
4184   PetscInt            k,anzi,*bi,*bj,*lnk,nlnk,arow,bnzi,nspacedouble=0;
4185   PetscInt            nrows,*buf_s,*buf_si,*buf_si_i,**nextrow,**nextai;
4186   MPI_Request         *si_waits,*sj_waits,*ri_waits,*rj_waits;
4187   MPI_Status          *status;
4188   PetscFreeSpaceList  free_space=NULL,current_space=NULL;
4189   PetscBT             lnkbt;
4190   Mat_Merge_SeqsToMPI *merge;
4191   PetscContainer      container;
4192 
4193   PetscFunctionBegin;
4194   ierr = PetscLogEventBegin(MAT_Seqstompisym,seqmat,0,0,0);CHKERRQ(ierr);
4195 
4196   /* make sure it is a PETSc comm */
4197   ierr = PetscCommDuplicate(comm,&comm,NULL);CHKERRQ(ierr);
4198   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
4199   ierr = MPI_Comm_rank(comm,&rank);CHKERRQ(ierr);
4200 
4201   ierr = PetscNew(&merge);CHKERRQ(ierr);
4202   ierr = PetscMalloc1(size,&status);CHKERRQ(ierr);
4203 
4204   /* determine row ownership */
4205   /*---------------------------------------------------------*/
4206   ierr = PetscLayoutCreate(comm,&merge->rowmap);CHKERRQ(ierr);
4207   ierr = PetscLayoutSetLocalSize(merge->rowmap,m);CHKERRQ(ierr);
4208   ierr = PetscLayoutSetSize(merge->rowmap,M);CHKERRQ(ierr);
4209   ierr = PetscLayoutSetBlockSize(merge->rowmap,1);CHKERRQ(ierr);
4210   ierr = PetscLayoutSetUp(merge->rowmap);CHKERRQ(ierr);
4211   ierr = PetscMalloc1(size,&len_si);CHKERRQ(ierr);
4212   ierr = PetscMalloc1(size,&merge->len_s);CHKERRQ(ierr);
4213 
4214   m      = merge->rowmap->n;
4215   owners = merge->rowmap->range;
4216 
4217   /* determine the number of messages to send, their lengths */
4218   /*---------------------------------------------------------*/
4219   len_s = merge->len_s;
4220 
4221   len          = 0; /* length of buf_si[] */
4222   merge->nsend = 0;
4223   for (proc=0; proc<size; proc++) {
4224     len_si[proc] = 0;
4225     if (proc == rank) {
4226       len_s[proc] = 0;
4227     } else {
4228       len_si[proc] = owners[proc+1] - owners[proc] + 1;
4229       len_s[proc]  = ai[owners[proc+1]] - ai[owners[proc]]; /* num of rows to be sent to [proc] */
4230     }
4231     if (len_s[proc]) {
4232       merge->nsend++;
4233       nrows = 0;
4234       for (i=owners[proc]; i<owners[proc+1]; i++) {
4235         if (ai[i+1] > ai[i]) nrows++;
4236       }
4237       len_si[proc] = 2*(nrows+1);
4238       len         += len_si[proc];
4239     }
4240   }
4241 
4242   /* determine the number and length of messages to receive for ij-structure */
4243   /*-------------------------------------------------------------------------*/
4244   ierr = PetscGatherNumberOfMessages(comm,NULL,len_s,&merge->nrecv);CHKERRQ(ierr);
4245   ierr = PetscGatherMessageLengths2(comm,merge->nsend,merge->nrecv,len_s,len_si,&merge->id_r,&merge->len_r,&len_ri);CHKERRQ(ierr);
4246 
4247   /* post the Irecv of j-structure */
4248   /*-------------------------------*/
4249   ierr = PetscCommGetNewTag(comm,&tagj);CHKERRQ(ierr);
4250   ierr = PetscPostIrecvInt(comm,tagj,merge->nrecv,merge->id_r,merge->len_r,&buf_rj,&rj_waits);CHKERRQ(ierr);
4251 
4252   /* post the Isend of j-structure */
4253   /*--------------------------------*/
4254   ierr = PetscMalloc2(merge->nsend,&si_waits,merge->nsend,&sj_waits);CHKERRQ(ierr);
4255 
4256   for (proc=0, k=0; proc<size; proc++) {
4257     if (!len_s[proc]) continue;
4258     i    = owners[proc];
4259     ierr = MPI_Isend(aj+ai[i],len_s[proc],MPIU_INT,proc,tagj,comm,sj_waits+k);CHKERRQ(ierr);
4260     k++;
4261   }
4262 
4263   /* receives and sends of j-structure are complete */
4264   /*------------------------------------------------*/
4265   if (merge->nrecv) {ierr = MPI_Waitall(merge->nrecv,rj_waits,status);CHKERRQ(ierr);}
4266   if (merge->nsend) {ierr = MPI_Waitall(merge->nsend,sj_waits,status);CHKERRQ(ierr);}
4267 
4268   /* send and recv i-structure */
4269   /*---------------------------*/
4270   ierr = PetscCommGetNewTag(comm,&tagi);CHKERRQ(ierr);
4271   ierr = PetscPostIrecvInt(comm,tagi,merge->nrecv,merge->id_r,len_ri,&buf_ri,&ri_waits);CHKERRQ(ierr);
4272 
4273   ierr   = PetscMalloc1(len+1,&buf_s);CHKERRQ(ierr);
4274   buf_si = buf_s;  /* points to the beginning of k-th msg to be sent */
4275   for (proc=0,k=0; proc<size; proc++) {
4276     if (!len_s[proc]) continue;
4277     /* form outgoing message for i-structure:
4278          buf_si[0]:                 nrows to be sent
4279                [1:nrows]:           row index (global)
4280                [nrows+1:2*nrows+1]: i-structure index
4281     */
4282     /*-------------------------------------------*/
4283     nrows       = len_si[proc]/2 - 1;
4284     buf_si_i    = buf_si + nrows+1;
4285     buf_si[0]   = nrows;
4286     buf_si_i[0] = 0;
4287     nrows       = 0;
4288     for (i=owners[proc]; i<owners[proc+1]; i++) {
4289       anzi = ai[i+1] - ai[i];
4290       if (anzi) {
4291         buf_si_i[nrows+1] = buf_si_i[nrows] + anzi; /* i-structure */
4292         buf_si[nrows+1]   = i-owners[proc]; /* local row index */
4293         nrows++;
4294       }
4295     }
4296     ierr = MPI_Isend(buf_si,len_si[proc],MPIU_INT,proc,tagi,comm,si_waits+k);CHKERRQ(ierr);
4297     k++;
4298     buf_si += len_si[proc];
4299   }
4300 
4301   if (merge->nrecv) {ierr = MPI_Waitall(merge->nrecv,ri_waits,status);CHKERRQ(ierr);}
4302   if (merge->nsend) {ierr = MPI_Waitall(merge->nsend,si_waits,status);CHKERRQ(ierr);}
4303 
4304   ierr = PetscInfo2(seqmat,"nsend: %D, nrecv: %D\n",merge->nsend,merge->nrecv);CHKERRQ(ierr);
4305   for (i=0; i<merge->nrecv; i++) {
4306     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);
4307   }
4308 
4309   ierr = PetscFree(len_si);CHKERRQ(ierr);
4310   ierr = PetscFree(len_ri);CHKERRQ(ierr);
4311   ierr = PetscFree(rj_waits);CHKERRQ(ierr);
4312   ierr = PetscFree2(si_waits,sj_waits);CHKERRQ(ierr);
4313   ierr = PetscFree(ri_waits);CHKERRQ(ierr);
4314   ierr = PetscFree(buf_s);CHKERRQ(ierr);
4315   ierr = PetscFree(status);CHKERRQ(ierr);
4316 
4317   /* compute a local seq matrix in each processor */
4318   /*----------------------------------------------*/
4319   /* allocate bi array and free space for accumulating nonzero column info */
4320   ierr  = PetscMalloc1(m+1,&bi);CHKERRQ(ierr);
4321   bi[0] = 0;
4322 
4323   /* create and initialize a linked list */
4324   nlnk = N+1;
4325   ierr = PetscLLCreate(N,N,nlnk,lnk,lnkbt);CHKERRQ(ierr);
4326 
4327   /* initial FreeSpace size is 2*(num of local nnz(seqmat)) */
4328   len  = ai[owners[rank+1]] - ai[owners[rank]];
4329   ierr = PetscFreeSpaceGet((PetscInt)(2*len+1),&free_space);CHKERRQ(ierr);
4330 
4331   current_space = free_space;
4332 
4333   /* determine symbolic info for each local row */
4334   ierr = PetscMalloc3(merge->nrecv,&buf_ri_k,merge->nrecv,&nextrow,merge->nrecv,&nextai);CHKERRQ(ierr);
4335 
4336   for (k=0; k<merge->nrecv; k++) {
4337     buf_ri_k[k] = buf_ri[k]; /* beginning of k-th recved i-structure */
4338     nrows       = *buf_ri_k[k];
4339     nextrow[k]  = buf_ri_k[k] + 1;  /* next row number of k-th recved i-structure */
4340     nextai[k]   = buf_ri_k[k] + (nrows + 1); /* poins to the next i-structure of k-th recved i-structure  */
4341   }
4342 
4343   ierr = MatPreallocateInitialize(comm,m,n,dnz,onz);CHKERRQ(ierr);
4344   len  = 0;
4345   for (i=0; i<m; i++) {
4346     bnzi = 0;
4347     /* add local non-zero cols of this proc's seqmat into lnk */
4348     arow  = owners[rank] + i;
4349     anzi  = ai[arow+1] - ai[arow];
4350     aj    = a->j + ai[arow];
4351     ierr  = PetscLLAddSorted(anzi,aj,N,nlnk,lnk,lnkbt);CHKERRQ(ierr);
4352     bnzi += nlnk;
4353     /* add received col data into lnk */
4354     for (k=0; k<merge->nrecv; k++) { /* k-th received message */
4355       if (i == *nextrow[k]) { /* i-th row */
4356         anzi  = *(nextai[k]+1) - *nextai[k];
4357         aj    = buf_rj[k] + *nextai[k];
4358         ierr  = PetscLLAddSorted(anzi,aj,N,nlnk,lnk,lnkbt);CHKERRQ(ierr);
4359         bnzi += nlnk;
4360         nextrow[k]++; nextai[k]++;
4361       }
4362     }
4363     if (len < bnzi) len = bnzi;  /* =max(bnzi) */
4364 
4365     /* if free space is not available, make more free space */
4366     if (current_space->local_remaining<bnzi) {
4367       ierr = PetscFreeSpaceGet(bnzi+current_space->total_array_size,&current_space);CHKERRQ(ierr);
4368       nspacedouble++;
4369     }
4370     /* copy data into free space, then initialize lnk */
4371     ierr = PetscLLClean(N,N,bnzi,lnk,current_space->array,lnkbt);CHKERRQ(ierr);
4372     ierr = MatPreallocateSet(i+owners[rank],bnzi,current_space->array,dnz,onz);CHKERRQ(ierr);
4373 
4374     current_space->array           += bnzi;
4375     current_space->local_used      += bnzi;
4376     current_space->local_remaining -= bnzi;
4377 
4378     bi[i+1] = bi[i] + bnzi;
4379   }
4380 
4381   ierr = PetscFree3(buf_ri_k,nextrow,nextai);CHKERRQ(ierr);
4382 
4383   ierr = PetscMalloc1(bi[m]+1,&bj);CHKERRQ(ierr);
4384   ierr = PetscFreeSpaceContiguous(&free_space,bj);CHKERRQ(ierr);
4385   ierr = PetscLLDestroy(lnk,lnkbt);CHKERRQ(ierr);
4386 
4387   /* create symbolic parallel matrix B_mpi */
4388   /*---------------------------------------*/
4389   ierr = MatGetBlockSizes(seqmat,&bs,&cbs);CHKERRQ(ierr);
4390   ierr = MatCreate(comm,&B_mpi);CHKERRQ(ierr);
4391   if (n==PETSC_DECIDE) {
4392     ierr = MatSetSizes(B_mpi,m,n,PETSC_DETERMINE,N);CHKERRQ(ierr);
4393   } else {
4394     ierr = MatSetSizes(B_mpi,m,n,PETSC_DETERMINE,PETSC_DETERMINE);CHKERRQ(ierr);
4395   }
4396   ierr = MatSetBlockSizes(B_mpi,bs,cbs);CHKERRQ(ierr);
4397   ierr = MatSetType(B_mpi,MATMPIAIJ);CHKERRQ(ierr);
4398   ierr = MatMPIAIJSetPreallocation(B_mpi,0,dnz,0,onz);CHKERRQ(ierr);
4399   ierr = MatPreallocateFinalize(dnz,onz);CHKERRQ(ierr);
4400   ierr = MatSetOption(B_mpi,MAT_NEW_NONZERO_ALLOCATION_ERR,PETSC_FALSE);CHKERRQ(ierr);
4401 
4402   /* B_mpi is not ready for use - assembly will be done by MatCreateMPIAIJSumSeqAIJNumeric() */
4403   B_mpi->assembled    = PETSC_FALSE;
4404   B_mpi->ops->destroy = MatDestroy_MPIAIJ_SeqsToMPI;
4405   merge->bi           = bi;
4406   merge->bj           = bj;
4407   merge->buf_ri       = buf_ri;
4408   merge->buf_rj       = buf_rj;
4409   merge->coi          = NULL;
4410   merge->coj          = NULL;
4411   merge->owners_co    = NULL;
4412 
4413   ierr = PetscCommDestroy(&comm);CHKERRQ(ierr);
4414 
4415   /* attach the supporting struct to B_mpi for reuse */
4416   ierr    = PetscContainerCreate(PETSC_COMM_SELF,&container);CHKERRQ(ierr);
4417   ierr    = PetscContainerSetPointer(container,merge);CHKERRQ(ierr);
4418   ierr    = PetscObjectCompose((PetscObject)B_mpi,"MatMergeSeqsToMPI",(PetscObject)container);CHKERRQ(ierr);
4419   ierr    = PetscContainerDestroy(&container);CHKERRQ(ierr);
4420   *mpimat = B_mpi;
4421 
4422   ierr = PetscLogEventEnd(MAT_Seqstompisym,seqmat,0,0,0);CHKERRQ(ierr);
4423   PetscFunctionReturn(0);
4424 }
4425 
4426 #undef __FUNCT__
4427 #define __FUNCT__ "MatCreateMPIAIJSumSeqAIJ"
4428 /*@C
4429       MatCreateMPIAIJSumSeqAIJ - Creates a MPIAIJ matrix by adding sequential
4430                  matrices from each processor
4431 
4432     Collective on MPI_Comm
4433 
4434    Input Parameters:
4435 +    comm - the communicators the parallel matrix will live on
4436 .    seqmat - the input sequential matrices
4437 .    m - number of local rows (or PETSC_DECIDE)
4438 .    n - number of local columns (or PETSC_DECIDE)
4439 -    scall - either MAT_INITIAL_MATRIX or MAT_REUSE_MATRIX
4440 
4441    Output Parameter:
4442 .    mpimat - the parallel matrix generated
4443 
4444     Level: advanced
4445 
4446    Notes:
4447      The dimensions of the sequential matrix in each processor MUST be the same.
4448      The input seqmat is included into the container "Mat_Merge_SeqsToMPI", and will be
4449      destroyed when mpimat is destroyed. Call PetscObjectQuery() to access seqmat.
4450 @*/
4451 PetscErrorCode  MatCreateMPIAIJSumSeqAIJ(MPI_Comm comm,Mat seqmat,PetscInt m,PetscInt n,MatReuse scall,Mat *mpimat)
4452 {
4453   PetscErrorCode ierr;
4454   PetscMPIInt    size;
4455 
4456   PetscFunctionBegin;
4457   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
4458   if (size == 1) {
4459     ierr = PetscLogEventBegin(MAT_Seqstompi,seqmat,0,0,0);CHKERRQ(ierr);
4460     if (scall == MAT_INITIAL_MATRIX) {
4461       ierr = MatDuplicate(seqmat,MAT_COPY_VALUES,mpimat);CHKERRQ(ierr);
4462     } else {
4463       ierr = MatCopy(seqmat,*mpimat,SAME_NONZERO_PATTERN);CHKERRQ(ierr);
4464     }
4465     ierr = PetscLogEventEnd(MAT_Seqstompi,seqmat,0,0,0);CHKERRQ(ierr);
4466     PetscFunctionReturn(0);
4467   }
4468   ierr = PetscLogEventBegin(MAT_Seqstompi,seqmat,0,0,0);CHKERRQ(ierr);
4469   if (scall == MAT_INITIAL_MATRIX) {
4470     ierr = MatCreateMPIAIJSumSeqAIJSymbolic(comm,seqmat,m,n,mpimat);CHKERRQ(ierr);
4471   }
4472   ierr = MatCreateMPIAIJSumSeqAIJNumeric(seqmat,*mpimat);CHKERRQ(ierr);
4473   ierr = PetscLogEventEnd(MAT_Seqstompi,seqmat,0,0,0);CHKERRQ(ierr);
4474   PetscFunctionReturn(0);
4475 }
4476 
4477 #undef __FUNCT__
4478 #define __FUNCT__ "MatMPIAIJGetLocalMat"
4479 /*@
4480      MatMPIAIJGetLocalMat - Creates a SeqAIJ from a MPIAIJ matrix by taking all its local rows and putting them into a sequential vector with
4481           mlocal rows and n columns. Where mlocal is the row count obtained with MatGetLocalSize() and n is the global column count obtained
4482           with MatGetSize()
4483 
4484     Not Collective
4485 
4486    Input Parameters:
4487 +    A - the matrix
4488 .    scall - either MAT_INITIAL_MATRIX or MAT_REUSE_MATRIX
4489 
4490    Output Parameter:
4491 .    A_loc - the local sequential matrix generated
4492 
4493     Level: developer
4494 
4495 .seealso: MatGetOwnerShipRange(), MatMPIAIJGetLocalMatCondensed()
4496 
4497 @*/
4498 PetscErrorCode  MatMPIAIJGetLocalMat(Mat A,MatReuse scall,Mat *A_loc)
4499 {
4500   PetscErrorCode ierr;
4501   Mat_MPIAIJ     *mpimat=(Mat_MPIAIJ*)A->data;
4502   Mat_SeqAIJ     *mat,*a,*b;
4503   PetscInt       *ai,*aj,*bi,*bj,*cmap=mpimat->garray;
4504   MatScalar      *aa,*ba,*cam;
4505   PetscScalar    *ca;
4506   PetscInt       am=A->rmap->n,i,j,k,cstart=A->cmap->rstart;
4507   PetscInt       *ci,*cj,col,ncols_d,ncols_o,jo;
4508   PetscBool      match;
4509   MPI_Comm       comm;
4510   PetscMPIInt    size;
4511 
4512   PetscFunctionBegin;
4513   ierr = PetscObjectTypeCompare((PetscObject)A,MATMPIAIJ,&match);CHKERRQ(ierr);
4514   if (!match) SETERRQ(PetscObjectComm((PetscObject)A), PETSC_ERR_SUP,"Requires MPIAIJ matrix as input");
4515   ierr = PetscObjectGetComm((PetscObject)A,&comm);CHKERRQ(ierr);
4516   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
4517   if (size == 1 && scall == MAT_REUSE_MATRIX) PetscFunctionReturn(0);
4518 
4519   ierr = PetscLogEventBegin(MAT_Getlocalmat,A,0,0,0);CHKERRQ(ierr);
4520   a = (Mat_SeqAIJ*)(mpimat->A)->data;
4521   b = (Mat_SeqAIJ*)(mpimat->B)->data;
4522   ai = a->i; aj = a->j; bi = b->i; bj = b->j;
4523   aa = a->a; ba = b->a;
4524   if (scall == MAT_INITIAL_MATRIX) {
4525     if (size == 1) {
4526       ierr = MatCreateSeqAIJWithArrays(PETSC_COMM_SELF,am,A->cmap->N,ai,aj,aa,A_loc);CHKERRQ(ierr);
4527       PetscFunctionReturn(0);
4528     }
4529 
4530     ierr  = PetscMalloc1(1+am,&ci);CHKERRQ(ierr);
4531     ci[0] = 0;
4532     for (i=0; i<am; i++) {
4533       ci[i+1] = ci[i] + (ai[i+1] - ai[i]) + (bi[i+1] - bi[i]);
4534     }
4535     ierr = PetscMalloc1(1+ci[am],&cj);CHKERRQ(ierr);
4536     ierr = PetscMalloc1(1+ci[am],&ca);CHKERRQ(ierr);
4537     k    = 0;
4538     for (i=0; i<am; i++) {
4539       ncols_o = bi[i+1] - bi[i];
4540       ncols_d = ai[i+1] - ai[i];
4541       /* off-diagonal portion of A */
4542       for (jo=0; jo<ncols_o; jo++) {
4543         col = cmap[*bj];
4544         if (col >= cstart) break;
4545         cj[k]   = col; bj++;
4546         ca[k++] = *ba++;
4547       }
4548       /* diagonal portion of A */
4549       for (j=0; j<ncols_d; j++) {
4550         cj[k]   = cstart + *aj++;
4551         ca[k++] = *aa++;
4552       }
4553       /* off-diagonal portion of A */
4554       for (j=jo; j<ncols_o; j++) {
4555         cj[k]   = cmap[*bj++];
4556         ca[k++] = *ba++;
4557       }
4558     }
4559     /* put together the new matrix */
4560     ierr = MatCreateSeqAIJWithArrays(PETSC_COMM_SELF,am,A->cmap->N,ci,cj,ca,A_loc);CHKERRQ(ierr);
4561     /* MatCreateSeqAIJWithArrays flags matrix so PETSc doesn't free the user's arrays. */
4562     /* Since these are PETSc arrays, change flags to free them as necessary. */
4563     mat          = (Mat_SeqAIJ*)(*A_loc)->data;
4564     mat->free_a  = PETSC_TRUE;
4565     mat->free_ij = PETSC_TRUE;
4566     mat->nonew   = 0;
4567   } else if (scall == MAT_REUSE_MATRIX) {
4568     mat=(Mat_SeqAIJ*)(*A_loc)->data;
4569     ci = mat->i; cj = mat->j; cam = mat->a;
4570     for (i=0; i<am; i++) {
4571       /* off-diagonal portion of A */
4572       ncols_o = bi[i+1] - bi[i];
4573       for (jo=0; jo<ncols_o; jo++) {
4574         col = cmap[*bj];
4575         if (col >= cstart) break;
4576         *cam++ = *ba++; bj++;
4577       }
4578       /* diagonal portion of A */
4579       ncols_d = ai[i+1] - ai[i];
4580       for (j=0; j<ncols_d; j++) *cam++ = *aa++;
4581       /* off-diagonal portion of A */
4582       for (j=jo; j<ncols_o; j++) {
4583         *cam++ = *ba++; bj++;
4584       }
4585     }
4586   } else SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONG,"Invalid MatReuse %d",(int)scall);
4587   ierr = PetscLogEventEnd(MAT_Getlocalmat,A,0,0,0);CHKERRQ(ierr);
4588   PetscFunctionReturn(0);
4589 }
4590 
4591 #undef __FUNCT__
4592 #define __FUNCT__ "MatMPIAIJGetLocalMatCondensed"
4593 /*@C
4594      MatMPIAIJGetLocalMatCondensed - Creates a SeqAIJ matrix from an MPIAIJ matrix by taking all its local rows and NON-ZERO columns
4595 
4596     Not Collective
4597 
4598    Input Parameters:
4599 +    A - the matrix
4600 .    scall - either MAT_INITIAL_MATRIX or MAT_REUSE_MATRIX
4601 -    row, col - index sets of rows and columns to extract (or NULL)
4602 
4603    Output Parameter:
4604 .    A_loc - the local sequential matrix generated
4605 
4606     Level: developer
4607 
4608 .seealso: MatGetOwnershipRange(), MatMPIAIJGetLocalMat()
4609 
4610 @*/
4611 PetscErrorCode  MatMPIAIJGetLocalMatCondensed(Mat A,MatReuse scall,IS *row,IS *col,Mat *A_loc)
4612 {
4613   Mat_MPIAIJ     *a=(Mat_MPIAIJ*)A->data;
4614   PetscErrorCode ierr;
4615   PetscInt       i,start,end,ncols,nzA,nzB,*cmap,imark,*idx;
4616   IS             isrowa,iscola;
4617   Mat            *aloc;
4618   PetscBool      match;
4619 
4620   PetscFunctionBegin;
4621   ierr = PetscObjectTypeCompare((PetscObject)A,MATMPIAIJ,&match);CHKERRQ(ierr);
4622   if (!match) SETERRQ(PetscObjectComm((PetscObject)A), PETSC_ERR_SUP,"Requires MPIAIJ matrix as input");
4623   ierr = PetscLogEventBegin(MAT_Getlocalmatcondensed,A,0,0,0);CHKERRQ(ierr);
4624   if (!row) {
4625     start = A->rmap->rstart; end = A->rmap->rend;
4626     ierr  = ISCreateStride(PETSC_COMM_SELF,end-start,start,1,&isrowa);CHKERRQ(ierr);
4627   } else {
4628     isrowa = *row;
4629   }
4630   if (!col) {
4631     start = A->cmap->rstart;
4632     cmap  = a->garray;
4633     nzA   = a->A->cmap->n;
4634     nzB   = a->B->cmap->n;
4635     ierr  = PetscMalloc1(nzA+nzB, &idx);CHKERRQ(ierr);
4636     ncols = 0;
4637     for (i=0; i<nzB; i++) {
4638       if (cmap[i] < start) idx[ncols++] = cmap[i];
4639       else break;
4640     }
4641     imark = i;
4642     for (i=0; i<nzA; i++) idx[ncols++] = start + i;
4643     for (i=imark; i<nzB; i++) idx[ncols++] = cmap[i];
4644     ierr = ISCreateGeneral(PETSC_COMM_SELF,ncols,idx,PETSC_OWN_POINTER,&iscola);CHKERRQ(ierr);
4645   } else {
4646     iscola = *col;
4647   }
4648   if (scall != MAT_INITIAL_MATRIX) {
4649     ierr    = PetscMalloc1(1,&aloc);CHKERRQ(ierr);
4650     aloc[0] = *A_loc;
4651   }
4652   ierr   = MatGetSubMatrices(A,1,&isrowa,&iscola,scall,&aloc);CHKERRQ(ierr);
4653   *A_loc = aloc[0];
4654   ierr   = PetscFree(aloc);CHKERRQ(ierr);
4655   if (!row) {
4656     ierr = ISDestroy(&isrowa);CHKERRQ(ierr);
4657   }
4658   if (!col) {
4659     ierr = ISDestroy(&iscola);CHKERRQ(ierr);
4660   }
4661   ierr = PetscLogEventEnd(MAT_Getlocalmatcondensed,A,0,0,0);CHKERRQ(ierr);
4662   PetscFunctionReturn(0);
4663 }
4664 
4665 #undef __FUNCT__
4666 #define __FUNCT__ "MatGetBrowsOfAcols"
4667 /*@C
4668     MatGetBrowsOfAcols - Creates a SeqAIJ matrix by taking rows of B that equal to nonzero columns of local A
4669 
4670     Collective on Mat
4671 
4672    Input Parameters:
4673 +    A,B - the matrices in mpiaij format
4674 .    scall - either MAT_INITIAL_MATRIX or MAT_REUSE_MATRIX
4675 -    rowb, colb - index sets of rows and columns of B to extract (or NULL)
4676 
4677    Output Parameter:
4678 +    rowb, colb - index sets of rows and columns of B to extract
4679 -    B_seq - the sequential matrix generated
4680 
4681     Level: developer
4682 
4683 @*/
4684 PetscErrorCode  MatGetBrowsOfAcols(Mat A,Mat B,MatReuse scall,IS *rowb,IS *colb,Mat *B_seq)
4685 {
4686   Mat_MPIAIJ     *a=(Mat_MPIAIJ*)A->data;
4687   PetscErrorCode ierr;
4688   PetscInt       *idx,i,start,ncols,nzA,nzB,*cmap,imark;
4689   IS             isrowb,iscolb;
4690   Mat            *bseq=NULL;
4691 
4692   PetscFunctionBegin;
4693   if (A->cmap->rstart != B->rmap->rstart || A->cmap->rend != B->rmap->rend) {
4694     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);
4695   }
4696   ierr = PetscLogEventBegin(MAT_GetBrowsOfAcols,A,B,0,0);CHKERRQ(ierr);
4697 
4698   if (scall == MAT_INITIAL_MATRIX) {
4699     start = A->cmap->rstart;
4700     cmap  = a->garray;
4701     nzA   = a->A->cmap->n;
4702     nzB   = a->B->cmap->n;
4703     ierr  = PetscMalloc1(nzA+nzB, &idx);CHKERRQ(ierr);
4704     ncols = 0;
4705     for (i=0; i<nzB; i++) {  /* row < local row index */
4706       if (cmap[i] < start) idx[ncols++] = cmap[i];
4707       else break;
4708     }
4709     imark = i;
4710     for (i=0; i<nzA; i++) idx[ncols++] = start + i;  /* local rows */
4711     for (i=imark; i<nzB; i++) idx[ncols++] = cmap[i]; /* row > local row index */
4712     ierr = ISCreateGeneral(PETSC_COMM_SELF,ncols,idx,PETSC_OWN_POINTER,&isrowb);CHKERRQ(ierr);
4713     ierr = ISCreateStride(PETSC_COMM_SELF,B->cmap->N,0,1,&iscolb);CHKERRQ(ierr);
4714   } else {
4715     if (!rowb || !colb) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_SUP,"IS rowb and colb must be provided for MAT_REUSE_MATRIX");
4716     isrowb  = *rowb; iscolb = *colb;
4717     ierr    = PetscMalloc1(1,&bseq);CHKERRQ(ierr);
4718     bseq[0] = *B_seq;
4719   }
4720   ierr   = MatGetSubMatrices(B,1,&isrowb,&iscolb,scall,&bseq);CHKERRQ(ierr);
4721   *B_seq = bseq[0];
4722   ierr   = PetscFree(bseq);CHKERRQ(ierr);
4723   if (!rowb) {
4724     ierr = ISDestroy(&isrowb);CHKERRQ(ierr);
4725   } else {
4726     *rowb = isrowb;
4727   }
4728   if (!colb) {
4729     ierr = ISDestroy(&iscolb);CHKERRQ(ierr);
4730   } else {
4731     *colb = iscolb;
4732   }
4733   ierr = PetscLogEventEnd(MAT_GetBrowsOfAcols,A,B,0,0);CHKERRQ(ierr);
4734   PetscFunctionReturn(0);
4735 }
4736 
4737 #undef __FUNCT__
4738 #define __FUNCT__ "MatGetBrowsOfAoCols_MPIAIJ"
4739 /*
4740     MatGetBrowsOfAoCols_MPIAIJ - Creates a SeqAIJ matrix by taking rows of B that equal to nonzero columns
4741     of the OFF-DIAGONAL portion of local A
4742 
4743     Collective on Mat
4744 
4745    Input Parameters:
4746 +    A,B - the matrices in mpiaij format
4747 -    scall - either MAT_INITIAL_MATRIX or MAT_REUSE_MATRIX
4748 
4749    Output Parameter:
4750 +    startsj_s - starting point in B's sending j-arrays, saved for MAT_REUSE (or NULL)
4751 .    startsj_r - starting point in B's receiving j-arrays, saved for MAT_REUSE (or NULL)
4752 .    bufa_ptr - array for sending matrix values, saved for MAT_REUSE (or NULL)
4753 -    B_oth - the sequential matrix generated with size aBn=a->B->cmap->n by B->cmap->N
4754 
4755     Level: developer
4756 
4757 */
4758 PetscErrorCode  MatGetBrowsOfAoCols_MPIAIJ(Mat A,Mat B,MatReuse scall,PetscInt **startsj_s,PetscInt **startsj_r,MatScalar **bufa_ptr,Mat *B_oth)
4759 {
4760   VecScatter_MPI_General *gen_to,*gen_from;
4761   PetscErrorCode         ierr;
4762   Mat_MPIAIJ             *a=(Mat_MPIAIJ*)A->data;
4763   Mat_SeqAIJ             *b_oth;
4764   VecScatter             ctx =a->Mvctx;
4765   MPI_Comm               comm;
4766   PetscMPIInt            *rprocs,*sprocs,tag=((PetscObject)ctx)->tag,rank;
4767   PetscInt               *rowlen,*bufj,*bufJ,ncols,aBn=a->B->cmap->n,row,*b_othi,*b_othj;
4768   PetscScalar            *rvalues,*svalues;
4769   MatScalar              *b_otha,*bufa,*bufA;
4770   PetscInt               i,j,k,l,ll,nrecvs,nsends,nrows,*srow,*rstarts,*rstartsj = 0,*sstarts,*sstartsj,len;
4771   MPI_Request            *rwaits = NULL,*swaits = NULL;
4772   MPI_Status             *sstatus,rstatus;
4773   PetscMPIInt            jj,size;
4774   PetscInt               *cols,sbs,rbs;
4775   PetscScalar            *vals;
4776 
4777   PetscFunctionBegin;
4778   ierr = PetscObjectGetComm((PetscObject)A,&comm);CHKERRQ(ierr);
4779   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
4780 
4781   if (A->cmap->rstart != B->rmap->rstart || A->cmap->rend != B->rmap->rend) {
4782     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);
4783   }
4784   ierr = PetscLogEventBegin(MAT_GetBrowsOfAocols,A,B,0,0);CHKERRQ(ierr);
4785   ierr = MPI_Comm_rank(comm,&rank);CHKERRQ(ierr);
4786 
4787   gen_to   = (VecScatter_MPI_General*)ctx->todata;
4788   gen_from = (VecScatter_MPI_General*)ctx->fromdata;
4789   rvalues  = gen_from->values; /* holds the length of receiving row */
4790   svalues  = gen_to->values;   /* holds the length of sending row */
4791   nrecvs   = gen_from->n;
4792   nsends   = gen_to->n;
4793 
4794   ierr    = PetscMalloc2(nrecvs,&rwaits,nsends,&swaits);CHKERRQ(ierr);
4795   srow    = gen_to->indices;    /* local row index to be sent */
4796   sstarts = gen_to->starts;
4797   sprocs  = gen_to->procs;
4798   sstatus = gen_to->sstatus;
4799   sbs     = gen_to->bs;
4800   rstarts = gen_from->starts;
4801   rprocs  = gen_from->procs;
4802   rbs     = gen_from->bs;
4803 
4804   if (!startsj_s || !bufa_ptr) scall = MAT_INITIAL_MATRIX;
4805   if (scall == MAT_INITIAL_MATRIX) {
4806     /* i-array */
4807     /*---------*/
4808     /*  post receives */
4809     for (i=0; i<nrecvs; i++) {
4810       rowlen = (PetscInt*)rvalues + rstarts[i]*rbs;
4811       nrows  = (rstarts[i+1]-rstarts[i])*rbs; /* num of indices to be received */
4812       ierr   = MPI_Irecv(rowlen,nrows,MPIU_INT,rprocs[i],tag,comm,rwaits+i);CHKERRQ(ierr);
4813     }
4814 
4815     /* pack the outgoing message */
4816     ierr = PetscMalloc2(nsends+1,&sstartsj,nrecvs+1,&rstartsj);CHKERRQ(ierr);
4817 
4818     sstartsj[0] = 0;
4819     rstartsj[0] = 0;
4820     len         = 0; /* total length of j or a array to be sent */
4821     k           = 0;
4822     for (i=0; i<nsends; i++) {
4823       rowlen = (PetscInt*)svalues + sstarts[i]*sbs;
4824       nrows  = sstarts[i+1]-sstarts[i]; /* num of block rows */
4825       for (j=0; j<nrows; j++) {
4826         row = srow[k] + B->rmap->range[rank]; /* global row idx */
4827         for (l=0; l<sbs; l++) {
4828           ierr = MatGetRow_MPIAIJ(B,row+l,&ncols,NULL,NULL);CHKERRQ(ierr); /* rowlength */
4829 
4830           rowlen[j*sbs+l] = ncols;
4831 
4832           len += ncols;
4833           ierr = MatRestoreRow_MPIAIJ(B,row+l,&ncols,NULL,NULL);CHKERRQ(ierr);
4834         }
4835         k++;
4836       }
4837       ierr = MPI_Isend(rowlen,nrows*sbs,MPIU_INT,sprocs[i],tag,comm,swaits+i);CHKERRQ(ierr);
4838 
4839       sstartsj[i+1] = len;  /* starting point of (i+1)-th outgoing msg in bufj and bufa */
4840     }
4841     /* recvs and sends of i-array are completed */
4842     i = nrecvs;
4843     while (i--) {
4844       ierr = MPI_Waitany(nrecvs,rwaits,&jj,&rstatus);CHKERRQ(ierr);
4845     }
4846     if (nsends) {ierr = MPI_Waitall(nsends,swaits,sstatus);CHKERRQ(ierr);}
4847 
4848     /* allocate buffers for sending j and a arrays */
4849     ierr = PetscMalloc1(len+1,&bufj);CHKERRQ(ierr);
4850     ierr = PetscMalloc1(len+1,&bufa);CHKERRQ(ierr);
4851 
4852     /* create i-array of B_oth */
4853     ierr = PetscMalloc1(aBn+2,&b_othi);CHKERRQ(ierr);
4854 
4855     b_othi[0] = 0;
4856     len       = 0; /* total length of j or a array to be received */
4857     k         = 0;
4858     for (i=0; i<nrecvs; i++) {
4859       rowlen = (PetscInt*)rvalues + rstarts[i]*rbs;
4860       nrows  = rbs*(rstarts[i+1]-rstarts[i]); /* num of rows to be recieved */
4861       for (j=0; j<nrows; j++) {
4862         b_othi[k+1] = b_othi[k] + rowlen[j];
4863         len        += rowlen[j]; k++;
4864       }
4865       rstartsj[i+1] = len; /* starting point of (i+1)-th incoming msg in bufj and bufa */
4866     }
4867 
4868     /* allocate space for j and a arrrays of B_oth */
4869     ierr = PetscMalloc1(b_othi[aBn]+1,&b_othj);CHKERRQ(ierr);
4870     ierr = PetscMalloc1(b_othi[aBn]+1,&b_otha);CHKERRQ(ierr);
4871 
4872     /* j-array */
4873     /*---------*/
4874     /*  post receives of j-array */
4875     for (i=0; i<nrecvs; i++) {
4876       nrows = rstartsj[i+1]-rstartsj[i]; /* length of the msg received */
4877       ierr  = MPI_Irecv(b_othj+rstartsj[i],nrows,MPIU_INT,rprocs[i],tag,comm,rwaits+i);CHKERRQ(ierr);
4878     }
4879 
4880     /* pack the outgoing message j-array */
4881     k = 0;
4882     for (i=0; i<nsends; i++) {
4883       nrows = sstarts[i+1]-sstarts[i]; /* num of block rows */
4884       bufJ  = bufj+sstartsj[i];
4885       for (j=0; j<nrows; j++) {
4886         row = srow[k++] + B->rmap->range[rank];  /* global row idx */
4887         for (ll=0; ll<sbs; ll++) {
4888           ierr = MatGetRow_MPIAIJ(B,row+ll,&ncols,&cols,NULL);CHKERRQ(ierr);
4889           for (l=0; l<ncols; l++) {
4890             *bufJ++ = cols[l];
4891           }
4892           ierr = MatRestoreRow_MPIAIJ(B,row+ll,&ncols,&cols,NULL);CHKERRQ(ierr);
4893         }
4894       }
4895       ierr = MPI_Isend(bufj+sstartsj[i],sstartsj[i+1]-sstartsj[i],MPIU_INT,sprocs[i],tag,comm,swaits+i);CHKERRQ(ierr);
4896     }
4897 
4898     /* recvs and sends of j-array are completed */
4899     i = nrecvs;
4900     while (i--) {
4901       ierr = MPI_Waitany(nrecvs,rwaits,&jj,&rstatus);CHKERRQ(ierr);
4902     }
4903     if (nsends) {ierr = MPI_Waitall(nsends,swaits,sstatus);CHKERRQ(ierr);}
4904   } else if (scall == MAT_REUSE_MATRIX) {
4905     sstartsj = *startsj_s;
4906     rstartsj = *startsj_r;
4907     bufa     = *bufa_ptr;
4908     b_oth    = (Mat_SeqAIJ*)(*B_oth)->data;
4909     b_otha   = b_oth->a;
4910   } else SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE, "Matrix P does not posses an object container");
4911 
4912   /* a-array */
4913   /*---------*/
4914   /*  post receives of a-array */
4915   for (i=0; i<nrecvs; i++) {
4916     nrows = rstartsj[i+1]-rstartsj[i]; /* length of the msg received */
4917     ierr  = MPI_Irecv(b_otha+rstartsj[i],nrows,MPIU_SCALAR,rprocs[i],tag,comm,rwaits+i);CHKERRQ(ierr);
4918   }
4919 
4920   /* pack the outgoing message a-array */
4921   k = 0;
4922   for (i=0; i<nsends; i++) {
4923     nrows = sstarts[i+1]-sstarts[i]; /* num of block rows */
4924     bufA  = bufa+sstartsj[i];
4925     for (j=0; j<nrows; j++) {
4926       row = srow[k++] + B->rmap->range[rank];  /* global row idx */
4927       for (ll=0; ll<sbs; ll++) {
4928         ierr = MatGetRow_MPIAIJ(B,row+ll,&ncols,NULL,&vals);CHKERRQ(ierr);
4929         for (l=0; l<ncols; l++) {
4930           *bufA++ = vals[l];
4931         }
4932         ierr = MatRestoreRow_MPIAIJ(B,row+ll,&ncols,NULL,&vals);CHKERRQ(ierr);
4933       }
4934     }
4935     ierr = MPI_Isend(bufa+sstartsj[i],sstartsj[i+1]-sstartsj[i],MPIU_SCALAR,sprocs[i],tag,comm,swaits+i);CHKERRQ(ierr);
4936   }
4937   /* recvs and sends of a-array are completed */
4938   i = nrecvs;
4939   while (i--) {
4940     ierr = MPI_Waitany(nrecvs,rwaits,&jj,&rstatus);CHKERRQ(ierr);
4941   }
4942   if (nsends) {ierr = MPI_Waitall(nsends,swaits,sstatus);CHKERRQ(ierr);}
4943   ierr = PetscFree2(rwaits,swaits);CHKERRQ(ierr);
4944 
4945   if (scall == MAT_INITIAL_MATRIX) {
4946     /* put together the new matrix */
4947     ierr = MatCreateSeqAIJWithArrays(PETSC_COMM_SELF,aBn,B->cmap->N,b_othi,b_othj,b_otha,B_oth);CHKERRQ(ierr);
4948 
4949     /* MatCreateSeqAIJWithArrays flags matrix so PETSc doesn't free the user's arrays. */
4950     /* Since these are PETSc arrays, change flags to free them as necessary. */
4951     b_oth          = (Mat_SeqAIJ*)(*B_oth)->data;
4952     b_oth->free_a  = PETSC_TRUE;
4953     b_oth->free_ij = PETSC_TRUE;
4954     b_oth->nonew   = 0;
4955 
4956     ierr = PetscFree(bufj);CHKERRQ(ierr);
4957     if (!startsj_s || !bufa_ptr) {
4958       ierr = PetscFree2(sstartsj,rstartsj);CHKERRQ(ierr);
4959       ierr = PetscFree(bufa_ptr);CHKERRQ(ierr);
4960     } else {
4961       *startsj_s = sstartsj;
4962       *startsj_r = rstartsj;
4963       *bufa_ptr  = bufa;
4964     }
4965   }
4966   ierr = PetscLogEventEnd(MAT_GetBrowsOfAocols,A,B,0,0);CHKERRQ(ierr);
4967   PetscFunctionReturn(0);
4968 }
4969 
4970 #undef __FUNCT__
4971 #define __FUNCT__ "MatGetCommunicationStructs"
4972 /*@C
4973   MatGetCommunicationStructs - Provides access to the communication structures used in matrix-vector multiplication.
4974 
4975   Not Collective
4976 
4977   Input Parameters:
4978 . A - The matrix in mpiaij format
4979 
4980   Output Parameter:
4981 + lvec - The local vector holding off-process values from the argument to a matrix-vector product
4982 . colmap - A map from global column index to local index into lvec
4983 - multScatter - A scatter from the argument of a matrix-vector product to lvec
4984 
4985   Level: developer
4986 
4987 @*/
4988 #if defined(PETSC_USE_CTABLE)
4989 PetscErrorCode  MatGetCommunicationStructs(Mat A, Vec *lvec, PetscTable *colmap, VecScatter *multScatter)
4990 #else
4991 PetscErrorCode  MatGetCommunicationStructs(Mat A, Vec *lvec, PetscInt *colmap[], VecScatter *multScatter)
4992 #endif
4993 {
4994   Mat_MPIAIJ *a;
4995 
4996   PetscFunctionBegin;
4997   PetscValidHeaderSpecific(A, MAT_CLASSID, 1);
4998   PetscValidPointer(lvec, 2);
4999   PetscValidPointer(colmap, 3);
5000   PetscValidPointer(multScatter, 4);
5001   a = (Mat_MPIAIJ*) A->data;
5002   if (lvec) *lvec = a->lvec;
5003   if (colmap) *colmap = a->colmap;
5004   if (multScatter) *multScatter = a->Mvctx;
5005   PetscFunctionReturn(0);
5006 }
5007 
5008 PETSC_EXTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJCRL(Mat,MatType,MatReuse,Mat*);
5009 PETSC_EXTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJPERM(Mat,MatType,MatReuse,Mat*);
5010 PETSC_EXTERN PetscErrorCode MatConvert_MPIAIJ_MPISBAIJ(Mat,MatType,MatReuse,Mat*);
5011 #if defined(PETSC_HAVE_ELEMENTAL)
5012 PETSC_EXTERN PetscErrorCode MatConvert_MPIAIJ_Elemental(Mat,MatType,MatReuse,Mat*);
5013 #endif
5014 
5015 #undef __FUNCT__
5016 #define __FUNCT__ "MatMatMultNumeric_MPIDense_MPIAIJ"
5017 /*
5018     Computes (B'*A')' since computing B*A directly is untenable
5019 
5020                n                       p                          p
5021         (              )       (              )         (                  )
5022       m (      A       )  *  n (       B      )   =   m (         C        )
5023         (              )       (              )         (                  )
5024 
5025 */
5026 PetscErrorCode MatMatMultNumeric_MPIDense_MPIAIJ(Mat A,Mat B,Mat C)
5027 {
5028   PetscErrorCode ierr;
5029   Mat            At,Bt,Ct;
5030 
5031   PetscFunctionBegin;
5032   ierr = MatTranspose(A,MAT_INITIAL_MATRIX,&At);CHKERRQ(ierr);
5033   ierr = MatTranspose(B,MAT_INITIAL_MATRIX,&Bt);CHKERRQ(ierr);
5034   ierr = MatMatMult(Bt,At,MAT_INITIAL_MATRIX,1.0,&Ct);CHKERRQ(ierr);
5035   ierr = MatDestroy(&At);CHKERRQ(ierr);
5036   ierr = MatDestroy(&Bt);CHKERRQ(ierr);
5037   ierr = MatTranspose(Ct,MAT_REUSE_MATRIX,&C);CHKERRQ(ierr);
5038   ierr = MatDestroy(&Ct);CHKERRQ(ierr);
5039   PetscFunctionReturn(0);
5040 }
5041 
5042 #undef __FUNCT__
5043 #define __FUNCT__ "MatMatMultSymbolic_MPIDense_MPIAIJ"
5044 PetscErrorCode MatMatMultSymbolic_MPIDense_MPIAIJ(Mat A,Mat B,PetscReal fill,Mat *C)
5045 {
5046   PetscErrorCode ierr;
5047   PetscInt       m=A->rmap->n,n=B->cmap->n;
5048   Mat            Cmat;
5049 
5050   PetscFunctionBegin;
5051   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);
5052   ierr = MatCreate(PetscObjectComm((PetscObject)A),&Cmat);CHKERRQ(ierr);
5053   ierr = MatSetSizes(Cmat,m,n,PETSC_DETERMINE,PETSC_DETERMINE);CHKERRQ(ierr);
5054   ierr = MatSetBlockSizesFromMats(Cmat,A,B);CHKERRQ(ierr);
5055   ierr = MatSetType(Cmat,MATMPIDENSE);CHKERRQ(ierr);
5056   ierr = MatMPIDenseSetPreallocation(Cmat,NULL);CHKERRQ(ierr);
5057   ierr = MatAssemblyBegin(Cmat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
5058   ierr = MatAssemblyEnd(Cmat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
5059 
5060   Cmat->ops->matmultnumeric = MatMatMultNumeric_MPIDense_MPIAIJ;
5061 
5062   *C = Cmat;
5063   PetscFunctionReturn(0);
5064 }
5065 
5066 /* ----------------------------------------------------------------*/
5067 #undef __FUNCT__
5068 #define __FUNCT__ "MatMatMult_MPIDense_MPIAIJ"
5069 PetscErrorCode MatMatMult_MPIDense_MPIAIJ(Mat A,Mat B,MatReuse scall,PetscReal fill,Mat *C)
5070 {
5071   PetscErrorCode ierr;
5072 
5073   PetscFunctionBegin;
5074   if (scall == MAT_INITIAL_MATRIX) {
5075     ierr = PetscLogEventBegin(MAT_MatMultSymbolic,A,B,0,0);CHKERRQ(ierr);
5076     ierr = MatMatMultSymbolic_MPIDense_MPIAIJ(A,B,fill,C);CHKERRQ(ierr);
5077     ierr = PetscLogEventEnd(MAT_MatMultSymbolic,A,B,0,0);CHKERRQ(ierr);
5078   }
5079   ierr = PetscLogEventBegin(MAT_MatMultNumeric,A,B,0,0);CHKERRQ(ierr);
5080   ierr = MatMatMultNumeric_MPIDense_MPIAIJ(A,B,*C);CHKERRQ(ierr);
5081   ierr = PetscLogEventEnd(MAT_MatMultNumeric,A,B,0,0);CHKERRQ(ierr);
5082   PetscFunctionReturn(0);
5083 }
5084 
5085 /*MC
5086    MATMPIAIJ - MATMPIAIJ = "mpiaij" - A matrix type to be used for parallel sparse matrices.
5087 
5088    Options Database Keys:
5089 . -mat_type mpiaij - sets the matrix type to "mpiaij" during a call to MatSetFromOptions()
5090 
5091   Level: beginner
5092 
5093 .seealso: MatCreateAIJ()
5094 M*/
5095 
5096 #undef __FUNCT__
5097 #define __FUNCT__ "MatCreate_MPIAIJ"
5098 PETSC_EXTERN PetscErrorCode MatCreate_MPIAIJ(Mat B)
5099 {
5100   Mat_MPIAIJ     *b;
5101   PetscErrorCode ierr;
5102   PetscMPIInt    size;
5103 
5104   PetscFunctionBegin;
5105   ierr = MPI_Comm_size(PetscObjectComm((PetscObject)B),&size);CHKERRQ(ierr);
5106 
5107   ierr          = PetscNewLog(B,&b);CHKERRQ(ierr);
5108   B->data       = (void*)b;
5109   ierr          = PetscMemcpy(B->ops,&MatOps_Values,sizeof(struct _MatOps));CHKERRQ(ierr);
5110   B->assembled  = PETSC_FALSE;
5111   B->insertmode = NOT_SET_VALUES;
5112   b->size       = size;
5113 
5114   ierr = MPI_Comm_rank(PetscObjectComm((PetscObject)B),&b->rank);CHKERRQ(ierr);
5115 
5116   /* build cache for off array entries formed */
5117   ierr = MatStashCreate_Private(PetscObjectComm((PetscObject)B),1,&B->stash);CHKERRQ(ierr);
5118 
5119   b->donotstash  = PETSC_FALSE;
5120   b->colmap      = 0;
5121   b->garray      = 0;
5122   b->roworiented = PETSC_TRUE;
5123 
5124   /* stuff used for matrix vector multiply */
5125   b->lvec  = NULL;
5126   b->Mvctx = NULL;
5127 
5128   /* stuff for MatGetRow() */
5129   b->rowindices   = 0;
5130   b->rowvalues    = 0;
5131   b->getrowactive = PETSC_FALSE;
5132 
5133   /* flexible pointer used in CUSP/CUSPARSE classes */
5134   b->spptr = NULL;
5135 
5136   ierr = PetscObjectComposeFunction((PetscObject)B,"MatMPIAIJSetUseScalableIncreaseOverlap_C",MatMPIAIJSetUseScalableIncreaseOverlap_MPIAIJ);CHKERRQ(ierr);
5137   ierr = PetscObjectComposeFunction((PetscObject)B,"MatStoreValues_C",MatStoreValues_MPIAIJ);CHKERRQ(ierr);
5138   ierr = PetscObjectComposeFunction((PetscObject)B,"MatRetrieveValues_C",MatRetrieveValues_MPIAIJ);CHKERRQ(ierr);
5139   ierr = PetscObjectComposeFunction((PetscObject)B,"MatGetDiagonalBlock_C",MatGetDiagonalBlock_MPIAIJ);CHKERRQ(ierr);
5140   ierr = PetscObjectComposeFunction((PetscObject)B,"MatIsTranspose_C",MatIsTranspose_MPIAIJ);CHKERRQ(ierr);
5141   ierr = PetscObjectComposeFunction((PetscObject)B,"MatMPIAIJSetPreallocation_C",MatMPIAIJSetPreallocation_MPIAIJ);CHKERRQ(ierr);
5142   ierr = PetscObjectComposeFunction((PetscObject)B,"MatMPIAIJSetPreallocationCSR_C",MatMPIAIJSetPreallocationCSR_MPIAIJ);CHKERRQ(ierr);
5143   ierr = PetscObjectComposeFunction((PetscObject)B,"MatDiagonalScaleLocal_C",MatDiagonalScaleLocal_MPIAIJ);CHKERRQ(ierr);
5144   ierr = PetscObjectComposeFunction((PetscObject)B,"MatConvert_mpiaij_mpiaijperm_C",MatConvert_MPIAIJ_MPIAIJPERM);CHKERRQ(ierr);
5145   ierr = PetscObjectComposeFunction((PetscObject)B,"MatConvert_mpiaij_mpiaijcrl_C",MatConvert_MPIAIJ_MPIAIJCRL);CHKERRQ(ierr);
5146   ierr = PetscObjectComposeFunction((PetscObject)B,"MatConvert_mpiaij_mpisbaij_C",MatConvert_MPIAIJ_MPISBAIJ);CHKERRQ(ierr);
5147 #if defined(PETSC_HAVE_ELEMENTAL)
5148   ierr = PetscObjectComposeFunction((PetscObject)B,"MatConvert_mpiaij_elemental_C",MatConvert_MPIAIJ_Elemental);CHKERRQ(ierr);
5149 #endif
5150   ierr = PetscObjectComposeFunction((PetscObject)B,"MatMatMult_mpidense_mpiaij_C",MatMatMult_MPIDense_MPIAIJ);CHKERRQ(ierr);
5151   ierr = PetscObjectComposeFunction((PetscObject)B,"MatMatMultSymbolic_mpidense_mpiaij_C",MatMatMultSymbolic_MPIDense_MPIAIJ);CHKERRQ(ierr);
5152   ierr = PetscObjectComposeFunction((PetscObject)B,"MatMatMultNumeric_mpidense_mpiaij_C",MatMatMultNumeric_MPIDense_MPIAIJ);CHKERRQ(ierr);
5153   ierr = PetscObjectChangeTypeName((PetscObject)B,MATMPIAIJ);CHKERRQ(ierr);
5154   PetscFunctionReturn(0);
5155 }
5156 
5157 #undef __FUNCT__
5158 #define __FUNCT__ "MatCreateMPIAIJWithSplitArrays"
5159 /*@C
5160      MatCreateMPIAIJWithSplitArrays - creates a MPI AIJ matrix using arrays that contain the "diagonal"
5161          and "off-diagonal" part of the matrix in CSR format.
5162 
5163    Collective on MPI_Comm
5164 
5165    Input Parameters:
5166 +  comm - MPI communicator
5167 .  m - number of local rows (Cannot be PETSC_DECIDE)
5168 .  n - This value should be the same as the local size used in creating the
5169        x vector for the matrix-vector product y = Ax. (or PETSC_DECIDE to have
5170        calculated if N is given) For square matrices n is almost always m.
5171 .  M - number of global rows (or PETSC_DETERMINE to have calculated if m is given)
5172 .  N - number of global columns (or PETSC_DETERMINE to have calculated if n is given)
5173 .   i - row indices for "diagonal" portion of matrix
5174 .   j - column indices
5175 .   a - matrix values
5176 .   oi - row indices for "off-diagonal" portion of matrix
5177 .   oj - column indices
5178 -   oa - matrix values
5179 
5180    Output Parameter:
5181 .   mat - the matrix
5182 
5183    Level: advanced
5184 
5185    Notes:
5186        The i, j, and a arrays ARE NOT copied by this routine into the internal format used by PETSc. The user
5187        must free the arrays once the matrix has been destroyed and not before.
5188 
5189        The i and j indices are 0 based
5190 
5191        See MatCreateAIJ() for the definition of "diagonal" and "off-diagonal" portion of the matrix
5192 
5193        This sets local rows and cannot be used to set off-processor values.
5194 
5195        Use of this routine is discouraged because it is inflexible and cumbersome to use. It is extremely rare that a
5196        legacy application natively assembles into exactly this split format. The code to do so is nontrivial and does
5197        not easily support in-place reassembly. It is recommended to use MatSetValues() (or a variant thereof) because
5198        the resulting assembly is easier to implement, will work with any matrix format, and the user does not have to
5199        keep track of the underlying array. Use MatSetOption(A,MAT_IGNORE_OFF_PROC_ENTRIES,PETSC_TRUE) to disable all
5200        communication if it is known that only local entries will be set.
5201 
5202 .keywords: matrix, aij, compressed row, sparse, parallel
5203 
5204 .seealso: MatCreate(), MatCreateSeqAIJ(), MatSetValues(), MatMPIAIJSetPreallocation(), MatMPIAIJSetPreallocationCSR(),
5205           MPIAIJ, MatCreateAIJ(), MatCreateMPIAIJWithArrays()
5206 @*/
5207 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)
5208 {
5209   PetscErrorCode ierr;
5210   Mat_MPIAIJ     *maij;
5211 
5212   PetscFunctionBegin;
5213   if (m < 0) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"local number of rows (m) cannot be PETSC_DECIDE, or negative");
5214   if (i[0]) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"i (row indices) must start with 0");
5215   if (oi[0]) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"oi (row indices) must start with 0");
5216   ierr = MatCreate(comm,mat);CHKERRQ(ierr);
5217   ierr = MatSetSizes(*mat,m,n,M,N);CHKERRQ(ierr);
5218   ierr = MatSetType(*mat,MATMPIAIJ);CHKERRQ(ierr);
5219   maij = (Mat_MPIAIJ*) (*mat)->data;
5220 
5221   (*mat)->preallocated = PETSC_TRUE;
5222 
5223   ierr = PetscLayoutSetUp((*mat)->rmap);CHKERRQ(ierr);
5224   ierr = PetscLayoutSetUp((*mat)->cmap);CHKERRQ(ierr);
5225 
5226   ierr = MatCreateSeqAIJWithArrays(PETSC_COMM_SELF,m,n,i,j,a,&maij->A);CHKERRQ(ierr);
5227   ierr = MatCreateSeqAIJWithArrays(PETSC_COMM_SELF,m,(*mat)->cmap->N,oi,oj,oa,&maij->B);CHKERRQ(ierr);
5228 
5229   ierr = MatAssemblyBegin(maij->A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
5230   ierr = MatAssemblyEnd(maij->A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
5231   ierr = MatAssemblyBegin(maij->B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
5232   ierr = MatAssemblyEnd(maij->B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
5233 
5234   ierr = MatAssemblyBegin(*mat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
5235   ierr = MatAssemblyEnd(*mat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
5236   ierr = MatSetOption(*mat,MAT_NEW_NONZERO_LOCATION_ERR,PETSC_TRUE);CHKERRQ(ierr);
5237   PetscFunctionReturn(0);
5238 }
5239 
5240 /*
5241     Special version for direct calls from Fortran
5242 */
5243 #include <petsc/private/fortranimpl.h>
5244 
5245 #if defined(PETSC_HAVE_FORTRAN_CAPS)
5246 #define matsetvaluesmpiaij_ MATSETVALUESMPIAIJ
5247 #elif !defined(PETSC_HAVE_FORTRAN_UNDERSCORE)
5248 #define matsetvaluesmpiaij_ matsetvaluesmpiaij
5249 #endif
5250 
5251 /* Change these macros so can be used in void function */
5252 #undef CHKERRQ
5253 #define CHKERRQ(ierr) CHKERRABORT(PETSC_COMM_WORLD,ierr)
5254 #undef SETERRQ2
5255 #define SETERRQ2(comm,ierr,b,c,d) CHKERRABORT(comm,ierr)
5256 #undef SETERRQ3
5257 #define SETERRQ3(comm,ierr,b,c,d,e) CHKERRABORT(comm,ierr)
5258 #undef SETERRQ
5259 #define SETERRQ(c,ierr,b) CHKERRABORT(c,ierr)
5260 
5261 #undef __FUNCT__
5262 #define __FUNCT__ "matsetvaluesmpiaij_"
5263 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)
5264 {
5265   Mat            mat  = *mmat;
5266   PetscInt       m    = *mm, n = *mn;
5267   InsertMode     addv = *maddv;
5268   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
5269   PetscScalar    value;
5270   PetscErrorCode ierr;
5271 
5272   MatCheckPreallocated(mat,1);
5273   if (mat->insertmode == NOT_SET_VALUES) mat->insertmode = addv;
5274 
5275 #if defined(PETSC_USE_DEBUG)
5276   else if (mat->insertmode != addv) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"Cannot mix add values and insert values");
5277 #endif
5278   {
5279     PetscInt  i,j,rstart  = mat->rmap->rstart,rend = mat->rmap->rend;
5280     PetscInt  cstart      = mat->cmap->rstart,cend = mat->cmap->rend,row,col;
5281     PetscBool roworiented = aij->roworiented;
5282 
5283     /* Some Variables required in the macro */
5284     Mat        A                 = aij->A;
5285     Mat_SeqAIJ *a                = (Mat_SeqAIJ*)A->data;
5286     PetscInt   *aimax            = a->imax,*ai = a->i,*ailen = a->ilen,*aj = a->j;
5287     MatScalar  *aa               = a->a;
5288     PetscBool  ignorezeroentries = (((a->ignorezeroentries)&&(addv==ADD_VALUES)) ? PETSC_TRUE : PETSC_FALSE);
5289     Mat        B                 = aij->B;
5290     Mat_SeqAIJ *b                = (Mat_SeqAIJ*)B->data;
5291     PetscInt   *bimax            = b->imax,*bi = b->i,*bilen = b->ilen,*bj = b->j,bm = aij->B->rmap->n,am = aij->A->rmap->n;
5292     MatScalar  *ba               = b->a;
5293 
5294     PetscInt  *rp1,*rp2,ii,nrow1,nrow2,_i,rmax1,rmax2,N,low1,high1,low2,high2,t,lastcol1,lastcol2;
5295     PetscInt  nonew = a->nonew;
5296     MatScalar *ap1,*ap2;
5297 
5298     PetscFunctionBegin;
5299     for (i=0; i<m; i++) {
5300       if (im[i] < 0) continue;
5301 #if defined(PETSC_USE_DEBUG)
5302       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);
5303 #endif
5304       if (im[i] >= rstart && im[i] < rend) {
5305         row      = im[i] - rstart;
5306         lastcol1 = -1;
5307         rp1      = aj + ai[row];
5308         ap1      = aa + ai[row];
5309         rmax1    = aimax[row];
5310         nrow1    = ailen[row];
5311         low1     = 0;
5312         high1    = nrow1;
5313         lastcol2 = -1;
5314         rp2      = bj + bi[row];
5315         ap2      = ba + bi[row];
5316         rmax2    = bimax[row];
5317         nrow2    = bilen[row];
5318         low2     = 0;
5319         high2    = nrow2;
5320 
5321         for (j=0; j<n; j++) {
5322           if (roworiented) value = v[i*n+j];
5323           else value = v[i+j*m];
5324           if (ignorezeroentries && value == 0.0 && (addv == ADD_VALUES)) continue;
5325           if (in[j] >= cstart && in[j] < cend) {
5326             col = in[j] - cstart;
5327             MatSetValues_SeqAIJ_A_Private(row,col,value,addv,im[i],in[j]);
5328           } else if (in[j] < 0) continue;
5329 #if defined(PETSC_USE_DEBUG)
5330           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);
5331 #endif
5332           else {
5333             if (mat->was_assembled) {
5334               if (!aij->colmap) {
5335                 ierr = MatCreateColmap_MPIAIJ_Private(mat);CHKERRQ(ierr);
5336               }
5337 #if defined(PETSC_USE_CTABLE)
5338               ierr = PetscTableFind(aij->colmap,in[j]+1,&col);CHKERRQ(ierr);
5339               col--;
5340 #else
5341               col = aij->colmap[in[j]] - 1;
5342 #endif
5343               if (col < 0 && !((Mat_SeqAIJ*)(aij->A->data))->nonew) {
5344                 ierr = MatDisAssemble_MPIAIJ(mat);CHKERRQ(ierr);
5345                 col  =  in[j];
5346                 /* Reinitialize the variables required by MatSetValues_SeqAIJ_B_Private() */
5347                 B     = aij->B;
5348                 b     = (Mat_SeqAIJ*)B->data;
5349                 bimax = b->imax; bi = b->i; bilen = b->ilen; bj = b->j;
5350                 rp2   = bj + bi[row];
5351                 ap2   = ba + bi[row];
5352                 rmax2 = bimax[row];
5353                 nrow2 = bilen[row];
5354                 low2  = 0;
5355                 high2 = nrow2;
5356                 bm    = aij->B->rmap->n;
5357                 ba    = b->a;
5358               }
5359             } else col = in[j];
5360             MatSetValues_SeqAIJ_B_Private(row,col,value,addv,im[i],in[j]);
5361           }
5362         }
5363       } else if (!aij->donotstash) {
5364         if (roworiented) {
5365           ierr = MatStashValuesRow_Private(&mat->stash,im[i],n,in,v+i*n,(PetscBool)(ignorezeroentries && (addv == ADD_VALUES)));CHKERRQ(ierr);
5366         } else {
5367           ierr = MatStashValuesCol_Private(&mat->stash,im[i],n,in,v+i,m,(PetscBool)(ignorezeroentries && (addv == ADD_VALUES)));CHKERRQ(ierr);
5368         }
5369       }
5370     }
5371   }
5372   PetscFunctionReturnVoid();
5373 }
5374 
5375