xref: /petsc/src/mat/impls/aij/mpi/mpiaij.c (revision b2566f29c2b6470df769aa9f7deb9e2726b0959e)
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 = MPIU_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 = MPIU_Allreduce(work,norms,n,MPIU_REAL,MPIU_MAX,PetscObjectComm((PetscObject)A));CHKERRQ(ierr);
181   } else {
182     ierr = MPIU_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 
686   PetscFunctionBegin;
687   if (aij->donotstash || mat->nooffprocentries) PetscFunctionReturn(0);
688 
689   ierr = MatStashScatterBegin_Private(mat,&mat->stash,mat->rmap->range);CHKERRQ(ierr);
690   ierr = MatStashGetInfo_Private(&mat->stash,&nstash,&reallocs);CHKERRQ(ierr);
691   ierr = PetscInfo2(aij->A,"Stash has %D entries, uses %D mallocs.\n",nstash,reallocs);CHKERRQ(ierr);
692   PetscFunctionReturn(0);
693 }
694 
695 #undef __FUNCT__
696 #define __FUNCT__ "MatAssemblyEnd_MPIAIJ"
697 PetscErrorCode MatAssemblyEnd_MPIAIJ(Mat mat,MatAssemblyType mode)
698 {
699   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
700   Mat_SeqAIJ     *a   = (Mat_SeqAIJ*)aij->A->data;
701   PetscErrorCode ierr;
702   PetscMPIInt    n;
703   PetscInt       i,j,rstart,ncols,flg;
704   PetscInt       *row,*col;
705   PetscBool      other_disassembled;
706   PetscScalar    *val;
707 
708   /* do not use 'b = (Mat_SeqAIJ*)aij->B->data' as B can be reset in disassembly */
709 
710   PetscFunctionBegin;
711   if (!aij->donotstash && !mat->nooffprocentries) {
712     while (1) {
713       ierr = MatStashScatterGetMesg_Private(&mat->stash,&n,&row,&col,&val,&flg);CHKERRQ(ierr);
714       if (!flg) break;
715 
716       for (i=0; i<n; ) {
717         /* Now identify the consecutive vals belonging to the same row */
718         for (j=i,rstart=row[j]; j<n; j++) {
719           if (row[j] != rstart) break;
720         }
721         if (j < n) ncols = j-i;
722         else       ncols = n-i;
723         /* Now assemble all these values with a single function call */
724         ierr = MatSetValues_MPIAIJ(mat,1,row+i,ncols,col+i,val+i,mat->insertmode);CHKERRQ(ierr);
725 
726         i = j;
727       }
728     }
729     ierr = MatStashScatterEnd_Private(&mat->stash);CHKERRQ(ierr);
730   }
731   ierr = MatAssemblyBegin(aij->A,mode);CHKERRQ(ierr);
732   ierr = MatAssemblyEnd(aij->A,mode);CHKERRQ(ierr);
733 
734   /* determine if any processor has disassembled, if so we must
735      also disassemble ourselfs, in order that we may reassemble. */
736   /*
737      if nonzero structure of submatrix B cannot change then we know that
738      no processor disassembled thus we can skip this stuff
739   */
740   if (!((Mat_SeqAIJ*)aij->B->data)->nonew) {
741     ierr = MPIU_Allreduce(&mat->was_assembled,&other_disassembled,1,MPIU_BOOL,MPI_PROD,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
742     if (mat->was_assembled && !other_disassembled) {
743       ierr = MatDisAssemble_MPIAIJ(mat);CHKERRQ(ierr);
744     }
745   }
746   if (!mat->was_assembled && mode == MAT_FINAL_ASSEMBLY) {
747     ierr = MatSetUpMultiply_MPIAIJ(mat);CHKERRQ(ierr);
748   }
749   ierr = MatSetOption(aij->B,MAT_USE_INODES,PETSC_FALSE);CHKERRQ(ierr);
750   ierr = MatAssemblyBegin(aij->B,mode);CHKERRQ(ierr);
751   ierr = MatAssemblyEnd(aij->B,mode);CHKERRQ(ierr);
752 
753   ierr = PetscFree2(aij->rowvalues,aij->rowindices);CHKERRQ(ierr);
754 
755   aij->rowvalues = 0;
756 
757   ierr = VecDestroy(&aij->diag);CHKERRQ(ierr);
758   if (a->inode.size) mat->ops->multdiagonalblock = MatMultDiagonalBlock_MPIAIJ;
759 
760   /* if no new nonzero locations are allowed in matrix then only set the matrix state the first time through */
761   if ((!mat->was_assembled && mode == MAT_FINAL_ASSEMBLY) || !((Mat_SeqAIJ*)(aij->A->data))->nonew) {
762     PetscObjectState state = aij->A->nonzerostate + aij->B->nonzerostate;
763     ierr = MPIU_Allreduce(&state,&mat->nonzerostate,1,MPIU_INT64,MPI_SUM,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
764   }
765   PetscFunctionReturn(0);
766 }
767 
768 #undef __FUNCT__
769 #define __FUNCT__ "MatZeroEntries_MPIAIJ"
770 PetscErrorCode MatZeroEntries_MPIAIJ(Mat A)
771 {
772   Mat_MPIAIJ     *l = (Mat_MPIAIJ*)A->data;
773   PetscErrorCode ierr;
774 
775   PetscFunctionBegin;
776   ierr = MatZeroEntries(l->A);CHKERRQ(ierr);
777   ierr = MatZeroEntries(l->B);CHKERRQ(ierr);
778   PetscFunctionReturn(0);
779 }
780 
781 #undef __FUNCT__
782 #define __FUNCT__ "MatZeroRows_MPIAIJ"
783 PetscErrorCode MatZeroRows_MPIAIJ(Mat A,PetscInt N,const PetscInt rows[],PetscScalar diag,Vec x,Vec b)
784 {
785   Mat_MPIAIJ    *mat    = (Mat_MPIAIJ *) A->data;
786   PetscInt      *owners = A->rmap->range;
787   PetscInt       n      = A->rmap->n;
788   PetscSF        sf;
789   PetscInt      *lrows;
790   PetscSFNode   *rrows;
791   PetscInt       r, p = 0, len = 0;
792   PetscErrorCode ierr;
793 
794   PetscFunctionBegin;
795   /* Create SF where leaves are input rows and roots are owned rows */
796   ierr = PetscMalloc1(n, &lrows);CHKERRQ(ierr);
797   for (r = 0; r < n; ++r) lrows[r] = -1;
798   if (!A->nooffproczerorows) {ierr = PetscMalloc1(N, &rrows);CHKERRQ(ierr);}
799   for (r = 0; r < N; ++r) {
800     const PetscInt idx   = rows[r];
801     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);
802     if (idx < owners[p] || owners[p+1] <= idx) { /* short-circuit the search if the last p owns this row too */
803       ierr = PetscLayoutFindOwner(A->rmap,idx,&p);CHKERRQ(ierr);
804     }
805     if (A->nooffproczerorows) {
806       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);
807       lrows[len++] = idx - owners[p];
808     } else {
809       rrows[r].rank = p;
810       rrows[r].index = rows[r] - owners[p];
811     }
812   }
813   if (!A->nooffproczerorows) {
814     ierr = PetscSFCreate(PetscObjectComm((PetscObject) A), &sf);CHKERRQ(ierr);
815     ierr = PetscSFSetGraph(sf, n, N, NULL, PETSC_OWN_POINTER, rrows, PETSC_OWN_POINTER);CHKERRQ(ierr);
816     /* Collect flags for rows to be zeroed */
817     ierr = PetscSFReduceBegin(sf, MPIU_INT, (PetscInt*)rows, lrows, MPI_LOR);CHKERRQ(ierr);
818     ierr = PetscSFReduceEnd(sf, MPIU_INT, (PetscInt*)rows, lrows, MPI_LOR);CHKERRQ(ierr);
819     ierr = PetscSFDestroy(&sf);CHKERRQ(ierr);
820     /* Compress and put in row numbers */
821     for (r = 0; r < n; ++r) if (lrows[r] >= 0) lrows[len++] = r;
822   }
823   /* fix right hand side if needed */
824   if (x && b) {
825     const PetscScalar *xx;
826     PetscScalar       *bb;
827 
828     ierr = VecGetArrayRead(x, &xx);CHKERRQ(ierr);
829     ierr = VecGetArray(b, &bb);CHKERRQ(ierr);
830     for (r = 0; r < len; ++r) bb[lrows[r]] = diag*xx[lrows[r]];
831     ierr = VecRestoreArrayRead(x, &xx);CHKERRQ(ierr);
832     ierr = VecRestoreArray(b, &bb);CHKERRQ(ierr);
833   }
834   /* Must zero l->B before l->A because the (diag) case below may put values into l->B*/
835   ierr = MatZeroRows(mat->B, len, lrows, 0.0, NULL, NULL);CHKERRQ(ierr);
836   if ((diag != 0.0) && (mat->A->rmap->N == mat->A->cmap->N)) {
837     ierr = MatZeroRows(mat->A, len, lrows, diag, NULL, NULL);CHKERRQ(ierr);
838   } else if (diag != 0.0) {
839     ierr = MatZeroRows(mat->A, len, lrows, 0.0, NULL, NULL);CHKERRQ(ierr);
840     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");
841     for (r = 0; r < len; ++r) {
842       const PetscInt row = lrows[r] + A->rmap->rstart;
843       ierr = MatSetValues(A, 1, &row, 1, &row, &diag, INSERT_VALUES);CHKERRQ(ierr);
844     }
845     ierr = MatAssemblyBegin(A, MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
846     ierr = MatAssemblyEnd(A, MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
847   } else {
848     ierr = MatZeroRows(mat->A, len, lrows, 0.0, NULL, NULL);CHKERRQ(ierr);
849   }
850   ierr = PetscFree(lrows);CHKERRQ(ierr);
851 
852   /* only change matrix nonzero state if pattern was allowed to be changed */
853   if (!((Mat_SeqAIJ*)(mat->A->data))->keepnonzeropattern) {
854     PetscObjectState state = mat->A->nonzerostate + mat->B->nonzerostate;
855     ierr = MPIU_Allreduce(&state,&A->nonzerostate,1,MPIU_INT64,MPI_SUM,PetscObjectComm((PetscObject)A));CHKERRQ(ierr);
856   }
857   PetscFunctionReturn(0);
858 }
859 
860 #undef __FUNCT__
861 #define __FUNCT__ "MatZeroRowsColumns_MPIAIJ"
862 PetscErrorCode MatZeroRowsColumns_MPIAIJ(Mat A,PetscInt N,const PetscInt rows[],PetscScalar diag,Vec x,Vec b)
863 {
864   Mat_MPIAIJ        *l = (Mat_MPIAIJ*)A->data;
865   PetscErrorCode    ierr;
866   PetscMPIInt       n = A->rmap->n;
867   PetscInt          i,j,r,m,p = 0,len = 0;
868   PetscInt          *lrows,*owners = A->rmap->range;
869   PetscSFNode       *rrows;
870   PetscSF           sf;
871   const PetscScalar *xx;
872   PetscScalar       *bb,*mask;
873   Vec               xmask,lmask;
874   Mat_SeqAIJ        *aij = (Mat_SeqAIJ*)l->B->data;
875   const PetscInt    *aj, *ii,*ridx;
876   PetscScalar       *aa;
877 
878   PetscFunctionBegin;
879   /* Create SF where leaves are input rows and roots are owned rows */
880   ierr = PetscMalloc1(n, &lrows);CHKERRQ(ierr);
881   for (r = 0; r < n; ++r) lrows[r] = -1;
882   ierr = PetscMalloc1(N, &rrows);CHKERRQ(ierr);
883   for (r = 0; r < N; ++r) {
884     const PetscInt idx   = rows[r];
885     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);
886     if (idx < owners[p] || owners[p+1] <= idx) { /* short-circuit the search if the last p owns this row too */
887       ierr = PetscLayoutFindOwner(A->rmap,idx,&p);CHKERRQ(ierr);
888     }
889     rrows[r].rank  = p;
890     rrows[r].index = rows[r] - owners[p];
891   }
892   ierr = PetscSFCreate(PetscObjectComm((PetscObject) A), &sf);CHKERRQ(ierr);
893   ierr = PetscSFSetGraph(sf, n, N, NULL, PETSC_OWN_POINTER, rrows, PETSC_OWN_POINTER);CHKERRQ(ierr);
894   /* Collect flags for rows to be zeroed */
895   ierr = PetscSFReduceBegin(sf, MPIU_INT, (PetscInt *) rows, lrows, MPI_LOR);CHKERRQ(ierr);
896   ierr = PetscSFReduceEnd(sf, MPIU_INT, (PetscInt *) rows, lrows, MPI_LOR);CHKERRQ(ierr);
897   ierr = PetscSFDestroy(&sf);CHKERRQ(ierr);
898   /* Compress and put in row numbers */
899   for (r = 0; r < n; ++r) if (lrows[r] >= 0) lrows[len++] = r;
900   /* zero diagonal part of matrix */
901   ierr = MatZeroRowsColumns(l->A,len,lrows,diag,x,b);CHKERRQ(ierr);
902   /* handle off diagonal part of matrix */
903   ierr = MatCreateVecs(A,&xmask,NULL);CHKERRQ(ierr);
904   ierr = VecDuplicate(l->lvec,&lmask);CHKERRQ(ierr);
905   ierr = VecGetArray(xmask,&bb);CHKERRQ(ierr);
906   for (i=0; i<len; i++) bb[lrows[i]] = 1;
907   ierr = VecRestoreArray(xmask,&bb);CHKERRQ(ierr);
908   ierr = VecScatterBegin(l->Mvctx,xmask,lmask,ADD_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
909   ierr = VecScatterEnd(l->Mvctx,xmask,lmask,ADD_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
910   ierr = VecDestroy(&xmask);CHKERRQ(ierr);
911   if (x) {
912     ierr = VecScatterBegin(l->Mvctx,x,l->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
913     ierr = VecScatterEnd(l->Mvctx,x,l->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
914     ierr = VecGetArrayRead(l->lvec,&xx);CHKERRQ(ierr);
915     ierr = VecGetArray(b,&bb);CHKERRQ(ierr);
916   }
917   ierr = VecGetArray(lmask,&mask);CHKERRQ(ierr);
918   /* remove zeroed rows of off diagonal matrix */
919   ii = aij->i;
920   for (i=0; i<len; i++) {
921     ierr = PetscMemzero(aij->a + ii[lrows[i]],(ii[lrows[i]+1] - ii[lrows[i]])*sizeof(PetscScalar));CHKERRQ(ierr);
922   }
923   /* loop over all elements of off process part of matrix zeroing removed columns*/
924   if (aij->compressedrow.use) {
925     m    = aij->compressedrow.nrows;
926     ii   = aij->compressedrow.i;
927     ridx = aij->compressedrow.rindex;
928     for (i=0; i<m; i++) {
929       n  = ii[i+1] - ii[i];
930       aj = aij->j + ii[i];
931       aa = aij->a + ii[i];
932 
933       for (j=0; j<n; j++) {
934         if (PetscAbsScalar(mask[*aj])) {
935           if (b) bb[*ridx] -= *aa*xx[*aj];
936           *aa = 0.0;
937         }
938         aa++;
939         aj++;
940       }
941       ridx++;
942     }
943   } else { /* do not use compressed row format */
944     m = l->B->rmap->n;
945     for (i=0; i<m; i++) {
946       n  = ii[i+1] - ii[i];
947       aj = aij->j + ii[i];
948       aa = aij->a + ii[i];
949       for (j=0; j<n; j++) {
950         if (PetscAbsScalar(mask[*aj])) {
951           if (b) bb[i] -= *aa*xx[*aj];
952           *aa = 0.0;
953         }
954         aa++;
955         aj++;
956       }
957     }
958   }
959   if (x) {
960     ierr = VecRestoreArray(b,&bb);CHKERRQ(ierr);
961     ierr = VecRestoreArrayRead(l->lvec,&xx);CHKERRQ(ierr);
962   }
963   ierr = VecRestoreArray(lmask,&mask);CHKERRQ(ierr);
964   ierr = VecDestroy(&lmask);CHKERRQ(ierr);
965   ierr = PetscFree(lrows);CHKERRQ(ierr);
966 
967   /* only change matrix nonzero state if pattern was allowed to be changed */
968   if (!((Mat_SeqAIJ*)(l->A->data))->keepnonzeropattern) {
969     PetscObjectState state = l->A->nonzerostate + l->B->nonzerostate;
970     ierr = MPIU_Allreduce(&state,&A->nonzerostate,1,MPIU_INT64,MPI_SUM,PetscObjectComm((PetscObject)A));CHKERRQ(ierr);
971   }
972   PetscFunctionReturn(0);
973 }
974 
975 #undef __FUNCT__
976 #define __FUNCT__ "MatMult_MPIAIJ"
977 PetscErrorCode MatMult_MPIAIJ(Mat A,Vec xx,Vec yy)
978 {
979   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
980   PetscErrorCode ierr;
981   PetscInt       nt;
982 
983   PetscFunctionBegin;
984   ierr = VecGetLocalSize(xx,&nt);CHKERRQ(ierr);
985   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);
986   ierr = VecScatterBegin(a->Mvctx,xx,a->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
987   ierr = (*a->A->ops->mult)(a->A,xx,yy);CHKERRQ(ierr);
988   ierr = VecScatterEnd(a->Mvctx,xx,a->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
989   ierr = (*a->B->ops->multadd)(a->B,a->lvec,yy,yy);CHKERRQ(ierr);
990   PetscFunctionReturn(0);
991 }
992 
993 #undef __FUNCT__
994 #define __FUNCT__ "MatMultDiagonalBlock_MPIAIJ"
995 PetscErrorCode MatMultDiagonalBlock_MPIAIJ(Mat A,Vec bb,Vec xx)
996 {
997   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
998   PetscErrorCode ierr;
999 
1000   PetscFunctionBegin;
1001   ierr = MatMultDiagonalBlock(a->A,bb,xx);CHKERRQ(ierr);
1002   PetscFunctionReturn(0);
1003 }
1004 
1005 #undef __FUNCT__
1006 #define __FUNCT__ "MatMultAdd_MPIAIJ"
1007 PetscErrorCode MatMultAdd_MPIAIJ(Mat A,Vec xx,Vec yy,Vec zz)
1008 {
1009   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
1010   PetscErrorCode ierr;
1011 
1012   PetscFunctionBegin;
1013   ierr = VecScatterBegin(a->Mvctx,xx,a->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1014   ierr = (*a->A->ops->multadd)(a->A,xx,yy,zz);CHKERRQ(ierr);
1015   ierr = VecScatterEnd(a->Mvctx,xx,a->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1016   ierr = (*a->B->ops->multadd)(a->B,a->lvec,zz,zz);CHKERRQ(ierr);
1017   PetscFunctionReturn(0);
1018 }
1019 
1020 #undef __FUNCT__
1021 #define __FUNCT__ "MatMultTranspose_MPIAIJ"
1022 PetscErrorCode MatMultTranspose_MPIAIJ(Mat A,Vec xx,Vec yy)
1023 {
1024   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
1025   PetscErrorCode ierr;
1026   PetscBool      merged;
1027 
1028   PetscFunctionBegin;
1029   ierr = VecScatterGetMerged(a->Mvctx,&merged);CHKERRQ(ierr);
1030   /* do nondiagonal part */
1031   ierr = (*a->B->ops->multtranspose)(a->B,xx,a->lvec);CHKERRQ(ierr);
1032   if (!merged) {
1033     /* send it on its way */
1034     ierr = VecScatterBegin(a->Mvctx,a->lvec,yy,ADD_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
1035     /* do local part */
1036     ierr = (*a->A->ops->multtranspose)(a->A,xx,yy);CHKERRQ(ierr);
1037     /* receive remote parts: note this assumes the values are not actually */
1038     /* added in yy until the next line, */
1039     ierr = VecScatterEnd(a->Mvctx,a->lvec,yy,ADD_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
1040   } else {
1041     /* do local part */
1042     ierr = (*a->A->ops->multtranspose)(a->A,xx,yy);CHKERRQ(ierr);
1043     /* send it on its way */
1044     ierr = VecScatterBegin(a->Mvctx,a->lvec,yy,ADD_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
1045     /* values actually were received in the Begin() but we need to call this nop */
1046     ierr = VecScatterEnd(a->Mvctx,a->lvec,yy,ADD_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
1047   }
1048   PetscFunctionReturn(0);
1049 }
1050 
1051 #undef __FUNCT__
1052 #define __FUNCT__ "MatIsTranspose_MPIAIJ"
1053 PetscErrorCode  MatIsTranspose_MPIAIJ(Mat Amat,Mat Bmat,PetscReal tol,PetscBool  *f)
1054 {
1055   MPI_Comm       comm;
1056   Mat_MPIAIJ     *Aij = (Mat_MPIAIJ*) Amat->data, *Bij;
1057   Mat            Adia = Aij->A, Bdia, Aoff,Boff,*Aoffs,*Boffs;
1058   IS             Me,Notme;
1059   PetscErrorCode ierr;
1060   PetscInt       M,N,first,last,*notme,i;
1061   PetscMPIInt    size;
1062 
1063   PetscFunctionBegin;
1064   /* Easy test: symmetric diagonal block */
1065   Bij  = (Mat_MPIAIJ*) Bmat->data; Bdia = Bij->A;
1066   ierr = MatIsTranspose(Adia,Bdia,tol,f);CHKERRQ(ierr);
1067   if (!*f) PetscFunctionReturn(0);
1068   ierr = PetscObjectGetComm((PetscObject)Amat,&comm);CHKERRQ(ierr);
1069   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
1070   if (size == 1) PetscFunctionReturn(0);
1071 
1072   /* Hard test: off-diagonal block. This takes a MatGetSubMatrix. */
1073   ierr = MatGetSize(Amat,&M,&N);CHKERRQ(ierr);
1074   ierr = MatGetOwnershipRange(Amat,&first,&last);CHKERRQ(ierr);
1075   ierr = PetscMalloc1(N-last+first,&notme);CHKERRQ(ierr);
1076   for (i=0; i<first; i++) notme[i] = i;
1077   for (i=last; i<M; i++) notme[i-last+first] = i;
1078   ierr = ISCreateGeneral(MPI_COMM_SELF,N-last+first,notme,PETSC_COPY_VALUES,&Notme);CHKERRQ(ierr);
1079   ierr = ISCreateStride(MPI_COMM_SELF,last-first,first,1,&Me);CHKERRQ(ierr);
1080   ierr = MatGetSubMatrices(Amat,1,&Me,&Notme,MAT_INITIAL_MATRIX,&Aoffs);CHKERRQ(ierr);
1081   Aoff = Aoffs[0];
1082   ierr = MatGetSubMatrices(Bmat,1,&Notme,&Me,MAT_INITIAL_MATRIX,&Boffs);CHKERRQ(ierr);
1083   Boff = Boffs[0];
1084   ierr = MatIsTranspose(Aoff,Boff,tol,f);CHKERRQ(ierr);
1085   ierr = MatDestroyMatrices(1,&Aoffs);CHKERRQ(ierr);
1086   ierr = MatDestroyMatrices(1,&Boffs);CHKERRQ(ierr);
1087   ierr = ISDestroy(&Me);CHKERRQ(ierr);
1088   ierr = ISDestroy(&Notme);CHKERRQ(ierr);
1089   ierr = PetscFree(notme);CHKERRQ(ierr);
1090   PetscFunctionReturn(0);
1091 }
1092 
1093 #undef __FUNCT__
1094 #define __FUNCT__ "MatMultTransposeAdd_MPIAIJ"
1095 PetscErrorCode MatMultTransposeAdd_MPIAIJ(Mat A,Vec xx,Vec yy,Vec zz)
1096 {
1097   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
1098   PetscErrorCode ierr;
1099 
1100   PetscFunctionBegin;
1101   /* do nondiagonal part */
1102   ierr = (*a->B->ops->multtranspose)(a->B,xx,a->lvec);CHKERRQ(ierr);
1103   /* send it on its way */
1104   ierr = VecScatterBegin(a->Mvctx,a->lvec,zz,ADD_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
1105   /* do local part */
1106   ierr = (*a->A->ops->multtransposeadd)(a->A,xx,yy,zz);CHKERRQ(ierr);
1107   /* receive remote parts */
1108   ierr = VecScatterEnd(a->Mvctx,a->lvec,zz,ADD_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
1109   PetscFunctionReturn(0);
1110 }
1111 
1112 /*
1113   This only works correctly for square matrices where the subblock A->A is the
1114    diagonal block
1115 */
1116 #undef __FUNCT__
1117 #define __FUNCT__ "MatGetDiagonal_MPIAIJ"
1118 PetscErrorCode MatGetDiagonal_MPIAIJ(Mat A,Vec v)
1119 {
1120   PetscErrorCode ierr;
1121   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
1122 
1123   PetscFunctionBegin;
1124   if (A->rmap->N != A->cmap->N) SETERRQ(PetscObjectComm((PetscObject)A),PETSC_ERR_SUP,"Supports only square matrix where A->A is diag block");
1125   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");
1126   ierr = MatGetDiagonal(a->A,v);CHKERRQ(ierr);
1127   PetscFunctionReturn(0);
1128 }
1129 
1130 #undef __FUNCT__
1131 #define __FUNCT__ "MatScale_MPIAIJ"
1132 PetscErrorCode MatScale_MPIAIJ(Mat A,PetscScalar aa)
1133 {
1134   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
1135   PetscErrorCode ierr;
1136 
1137   PetscFunctionBegin;
1138   ierr = MatScale(a->A,aa);CHKERRQ(ierr);
1139   ierr = MatScale(a->B,aa);CHKERRQ(ierr);
1140   PetscFunctionReturn(0);
1141 }
1142 
1143 #undef __FUNCT__
1144 #define __FUNCT__ "MatDestroy_MPIAIJ"
1145 PetscErrorCode MatDestroy_MPIAIJ(Mat mat)
1146 {
1147   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
1148   PetscErrorCode ierr;
1149 
1150   PetscFunctionBegin;
1151 #if defined(PETSC_USE_LOG)
1152   PetscLogObjectState((PetscObject)mat,"Rows=%D, Cols=%D",mat->rmap->N,mat->cmap->N);
1153 #endif
1154   ierr = MatStashDestroy_Private(&mat->stash);CHKERRQ(ierr);
1155   ierr = VecDestroy(&aij->diag);CHKERRQ(ierr);
1156   ierr = MatDestroy(&aij->A);CHKERRQ(ierr);
1157   ierr = MatDestroy(&aij->B);CHKERRQ(ierr);
1158 #if defined(PETSC_USE_CTABLE)
1159   ierr = PetscTableDestroy(&aij->colmap);CHKERRQ(ierr);
1160 #else
1161   ierr = PetscFree(aij->colmap);CHKERRQ(ierr);
1162 #endif
1163   ierr = PetscFree(aij->garray);CHKERRQ(ierr);
1164   ierr = VecDestroy(&aij->lvec);CHKERRQ(ierr);
1165   ierr = VecScatterDestroy(&aij->Mvctx);CHKERRQ(ierr);
1166   ierr = PetscFree2(aij->rowvalues,aij->rowindices);CHKERRQ(ierr);
1167   ierr = PetscFree(aij->ld);CHKERRQ(ierr);
1168   ierr = PetscFree(mat->data);CHKERRQ(ierr);
1169 
1170   ierr = PetscObjectChangeTypeName((PetscObject)mat,0);CHKERRQ(ierr);
1171   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatStoreValues_C",NULL);CHKERRQ(ierr);
1172   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatRetrieveValues_C",NULL);CHKERRQ(ierr);
1173   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatGetDiagonalBlock_C",NULL);CHKERRQ(ierr);
1174   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatIsTranspose_C",NULL);CHKERRQ(ierr);
1175   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatMPIAIJSetPreallocation_C",NULL);CHKERRQ(ierr);
1176   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatMPIAIJSetPreallocationCSR_C",NULL);CHKERRQ(ierr);
1177   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatDiagonalScaleLocal_C",NULL);CHKERRQ(ierr);
1178   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatConvert_mpiaij_mpisbaij_C",NULL);CHKERRQ(ierr);
1179 #if defined(PETSC_HAVE_ELEMENTAL)
1180   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatConvert_mpiaij_elemental_C",NULL);CHKERRQ(ierr);
1181 #endif
1182   PetscFunctionReturn(0);
1183 }
1184 
1185 #undef __FUNCT__
1186 #define __FUNCT__ "MatView_MPIAIJ_Binary"
1187 PetscErrorCode MatView_MPIAIJ_Binary(Mat mat,PetscViewer viewer)
1188 {
1189   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
1190   Mat_SeqAIJ     *A   = (Mat_SeqAIJ*)aij->A->data;
1191   Mat_SeqAIJ     *B   = (Mat_SeqAIJ*)aij->B->data;
1192   PetscErrorCode ierr;
1193   PetscMPIInt    rank,size,tag = ((PetscObject)viewer)->tag;
1194   int            fd;
1195   PetscInt       nz,header[4],*row_lengths,*range=0,rlen,i;
1196   PetscInt       nzmax,*column_indices,j,k,col,*garray = aij->garray,cnt,cstart = mat->cmap->rstart,rnz = 0;
1197   PetscScalar    *column_values;
1198   PetscInt       message_count,flowcontrolcount;
1199   FILE           *file;
1200 
1201   PetscFunctionBegin;
1202   ierr = MPI_Comm_rank(PetscObjectComm((PetscObject)mat),&rank);CHKERRQ(ierr);
1203   ierr = MPI_Comm_size(PetscObjectComm((PetscObject)mat),&size);CHKERRQ(ierr);
1204   nz   = A->nz + B->nz;
1205   ierr = PetscViewerBinaryGetDescriptor(viewer,&fd);CHKERRQ(ierr);
1206   if (!rank) {
1207     header[0] = MAT_FILE_CLASSID;
1208     header[1] = mat->rmap->N;
1209     header[2] = mat->cmap->N;
1210 
1211     ierr = MPI_Reduce(&nz,&header[3],1,MPIU_INT,MPI_SUM,0,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1212     ierr = PetscBinaryWrite(fd,header,4,PETSC_INT,PETSC_TRUE);CHKERRQ(ierr);
1213     /* get largest number of rows any processor has */
1214     rlen  = mat->rmap->n;
1215     range = mat->rmap->range;
1216     for (i=1; i<size; i++) rlen = PetscMax(rlen,range[i+1] - range[i]);
1217   } else {
1218     ierr = MPI_Reduce(&nz,0,1,MPIU_INT,MPI_SUM,0,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1219     rlen = mat->rmap->n;
1220   }
1221 
1222   /* load up the local row counts */
1223   ierr = PetscMalloc1(rlen+1,&row_lengths);CHKERRQ(ierr);
1224   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];
1225 
1226   /* store the row lengths to the file */
1227   ierr = PetscViewerFlowControlStart(viewer,&message_count,&flowcontrolcount);CHKERRQ(ierr);
1228   if (!rank) {
1229     ierr = PetscBinaryWrite(fd,row_lengths,mat->rmap->n,PETSC_INT,PETSC_TRUE);CHKERRQ(ierr);
1230     for (i=1; i<size; i++) {
1231       ierr = PetscViewerFlowControlStepMaster(viewer,i,&message_count,flowcontrolcount);CHKERRQ(ierr);
1232       rlen = range[i+1] - range[i];
1233       ierr = MPIULong_Recv(row_lengths,rlen,MPIU_INT,i,tag,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1234       ierr = PetscBinaryWrite(fd,row_lengths,rlen,PETSC_INT,PETSC_TRUE);CHKERRQ(ierr);
1235     }
1236     ierr = PetscViewerFlowControlEndMaster(viewer,&message_count);CHKERRQ(ierr);
1237   } else {
1238     ierr = PetscViewerFlowControlStepWorker(viewer,rank,&message_count);CHKERRQ(ierr);
1239     ierr = MPIULong_Send(row_lengths,mat->rmap->n,MPIU_INT,0,tag,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1240     ierr = PetscViewerFlowControlEndWorker(viewer,&message_count);CHKERRQ(ierr);
1241   }
1242   ierr = PetscFree(row_lengths);CHKERRQ(ierr);
1243 
1244   /* load up the local column indices */
1245   nzmax = nz; /* th processor needs space a largest processor needs */
1246   ierr  = MPI_Reduce(&nz,&nzmax,1,MPIU_INT,MPI_MAX,0,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1247   ierr  = PetscMalloc1(nzmax+1,&column_indices);CHKERRQ(ierr);
1248   cnt   = 0;
1249   for (i=0; i<mat->rmap->n; i++) {
1250     for (j=B->i[i]; j<B->i[i+1]; j++) {
1251       if ((col = garray[B->j[j]]) > cstart) break;
1252       column_indices[cnt++] = col;
1253     }
1254     for (k=A->i[i]; k<A->i[i+1]; k++) column_indices[cnt++] = A->j[k] + cstart;
1255     for (; j<B->i[i+1]; j++) column_indices[cnt++] = garray[B->j[j]];
1256   }
1257   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);
1258 
1259   /* store the column indices to the file */
1260   ierr = PetscViewerFlowControlStart(viewer,&message_count,&flowcontrolcount);CHKERRQ(ierr);
1261   if (!rank) {
1262     MPI_Status status;
1263     ierr = PetscBinaryWrite(fd,column_indices,nz,PETSC_INT,PETSC_TRUE);CHKERRQ(ierr);
1264     for (i=1; i<size; i++) {
1265       ierr = PetscViewerFlowControlStepMaster(viewer,i,&message_count,flowcontrolcount);CHKERRQ(ierr);
1266       ierr = MPI_Recv(&rnz,1,MPIU_INT,i,tag,PetscObjectComm((PetscObject)mat),&status);CHKERRQ(ierr);
1267       if (rnz > nzmax) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_LIB,"Internal PETSc error: nz = %D nzmax = %D",nz,nzmax);
1268       ierr = MPIULong_Recv(column_indices,rnz,MPIU_INT,i,tag,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1269       ierr = PetscBinaryWrite(fd,column_indices,rnz,PETSC_INT,PETSC_TRUE);CHKERRQ(ierr);
1270     }
1271     ierr = PetscViewerFlowControlEndMaster(viewer,&message_count);CHKERRQ(ierr);
1272   } else {
1273     ierr = PetscViewerFlowControlStepWorker(viewer,rank,&message_count);CHKERRQ(ierr);
1274     ierr = MPI_Send(&nz,1,MPIU_INT,0,tag,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1275     ierr = MPIULong_Send(column_indices,nz,MPIU_INT,0,tag,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1276     ierr = PetscViewerFlowControlEndWorker(viewer,&message_count);CHKERRQ(ierr);
1277   }
1278   ierr = PetscFree(column_indices);CHKERRQ(ierr);
1279 
1280   /* load up the local column values */
1281   ierr = PetscMalloc1(nzmax+1,&column_values);CHKERRQ(ierr);
1282   cnt  = 0;
1283   for (i=0; i<mat->rmap->n; i++) {
1284     for (j=B->i[i]; j<B->i[i+1]; j++) {
1285       if (garray[B->j[j]] > cstart) break;
1286       column_values[cnt++] = B->a[j];
1287     }
1288     for (k=A->i[i]; k<A->i[i+1]; k++) column_values[cnt++] = A->a[k];
1289     for (; j<B->i[i+1]; j++) column_values[cnt++] = B->a[j];
1290   }
1291   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);
1292 
1293   /* store the column values to the file */
1294   ierr = PetscViewerFlowControlStart(viewer,&message_count,&flowcontrolcount);CHKERRQ(ierr);
1295   if (!rank) {
1296     MPI_Status status;
1297     ierr = PetscBinaryWrite(fd,column_values,nz,PETSC_SCALAR,PETSC_TRUE);CHKERRQ(ierr);
1298     for (i=1; i<size; i++) {
1299       ierr = PetscViewerFlowControlStepMaster(viewer,i,&message_count,flowcontrolcount);CHKERRQ(ierr);
1300       ierr = MPI_Recv(&rnz,1,MPIU_INT,i,tag,PetscObjectComm((PetscObject)mat),&status);CHKERRQ(ierr);
1301       if (rnz > nzmax) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_LIB,"Internal PETSc error: nz = %D nzmax = %D",nz,nzmax);
1302       ierr = MPIULong_Recv(column_values,rnz,MPIU_SCALAR,i,tag,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1303       ierr = PetscBinaryWrite(fd,column_values,rnz,PETSC_SCALAR,PETSC_TRUE);CHKERRQ(ierr);
1304     }
1305     ierr = PetscViewerFlowControlEndMaster(viewer,&message_count);CHKERRQ(ierr);
1306   } else {
1307     ierr = PetscViewerFlowControlStepWorker(viewer,rank,&message_count);CHKERRQ(ierr);
1308     ierr = MPI_Send(&nz,1,MPIU_INT,0,tag,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1309     ierr = MPIULong_Send(column_values,nz,MPIU_SCALAR,0,tag,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1310     ierr = PetscViewerFlowControlEndWorker(viewer,&message_count);CHKERRQ(ierr);
1311   }
1312   ierr = PetscFree(column_values);CHKERRQ(ierr);
1313 
1314   ierr = PetscViewerBinaryGetInfoPointer(viewer,&file);CHKERRQ(ierr);
1315   if (file) fprintf(file,"-matload_block_size %d\n",(int)PetscAbs(mat->rmap->bs));
1316   PetscFunctionReturn(0);
1317 }
1318 
1319 #include <petscdraw.h>
1320 #undef __FUNCT__
1321 #define __FUNCT__ "MatView_MPIAIJ_ASCIIorDraworSocket"
1322 PetscErrorCode MatView_MPIAIJ_ASCIIorDraworSocket(Mat mat,PetscViewer viewer)
1323 {
1324   Mat_MPIAIJ        *aij = (Mat_MPIAIJ*)mat->data;
1325   PetscErrorCode    ierr;
1326   PetscMPIInt       rank = aij->rank,size = aij->size;
1327   PetscBool         isdraw,iascii,isbinary;
1328   PetscViewer       sviewer;
1329   PetscViewerFormat format;
1330 
1331   PetscFunctionBegin;
1332   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERDRAW,&isdraw);CHKERRQ(ierr);
1333   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERASCII,&iascii);CHKERRQ(ierr);
1334   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERBINARY,&isbinary);CHKERRQ(ierr);
1335   if (iascii) {
1336     ierr = PetscViewerGetFormat(viewer,&format);CHKERRQ(ierr);
1337     if (format == PETSC_VIEWER_ASCII_INFO_DETAIL) {
1338       MatInfo   info;
1339       PetscBool inodes;
1340 
1341       ierr = MPI_Comm_rank(PetscObjectComm((PetscObject)mat),&rank);CHKERRQ(ierr);
1342       ierr = MatGetInfo(mat,MAT_LOCAL,&info);CHKERRQ(ierr);
1343       ierr = MatInodeGetInodeSizes(aij->A,NULL,(PetscInt**)&inodes,NULL);CHKERRQ(ierr);
1344       ierr = PetscViewerASCIIPushSynchronized(viewer);CHKERRQ(ierr);
1345       if (!inodes) {
1346         ierr = PetscViewerASCIISynchronizedPrintf(viewer,"[%d] Local rows %D nz %D nz alloced %D mem %D, not using I-node routines\n",
1347                                                   rank,mat->rmap->n,(PetscInt)info.nz_used,(PetscInt)info.nz_allocated,(PetscInt)info.memory);CHKERRQ(ierr);
1348       } else {
1349         ierr = PetscViewerASCIISynchronizedPrintf(viewer,"[%d] Local rows %D nz %D nz alloced %D mem %D, using I-node routines\n",
1350                                                   rank,mat->rmap->n,(PetscInt)info.nz_used,(PetscInt)info.nz_allocated,(PetscInt)info.memory);CHKERRQ(ierr);
1351       }
1352       ierr = MatGetInfo(aij->A,MAT_LOCAL,&info);CHKERRQ(ierr);
1353       ierr = PetscViewerASCIISynchronizedPrintf(viewer,"[%d] on-diagonal part: nz %D \n",rank,(PetscInt)info.nz_used);CHKERRQ(ierr);
1354       ierr = MatGetInfo(aij->B,MAT_LOCAL,&info);CHKERRQ(ierr);
1355       ierr = PetscViewerASCIISynchronizedPrintf(viewer,"[%d] off-diagonal part: nz %D \n",rank,(PetscInt)info.nz_used);CHKERRQ(ierr);
1356       ierr = PetscViewerFlush(viewer);CHKERRQ(ierr);
1357       ierr = PetscViewerASCIIPopSynchronized(viewer);CHKERRQ(ierr);
1358       ierr = PetscViewerASCIIPrintf(viewer,"Information on VecScatter used in matrix-vector product: \n");CHKERRQ(ierr);
1359       ierr = VecScatterView(aij->Mvctx,viewer);CHKERRQ(ierr);
1360       PetscFunctionReturn(0);
1361     } else if (format == PETSC_VIEWER_ASCII_INFO) {
1362       PetscInt inodecount,inodelimit,*inodes;
1363       ierr = MatInodeGetInodeSizes(aij->A,&inodecount,&inodes,&inodelimit);CHKERRQ(ierr);
1364       if (inodes) {
1365         ierr = PetscViewerASCIIPrintf(viewer,"using I-node (on process 0) routines: found %D nodes, limit used is %D\n",inodecount,inodelimit);CHKERRQ(ierr);
1366       } else {
1367         ierr = PetscViewerASCIIPrintf(viewer,"not using I-node (on process 0) routines\n");CHKERRQ(ierr);
1368       }
1369       PetscFunctionReturn(0);
1370     } else if (format == PETSC_VIEWER_ASCII_FACTOR_INFO) {
1371       PetscFunctionReturn(0);
1372     }
1373   } else if (isbinary) {
1374     if (size == 1) {
1375       ierr = PetscObjectSetName((PetscObject)aij->A,((PetscObject)mat)->name);CHKERRQ(ierr);
1376       ierr = MatView(aij->A,viewer);CHKERRQ(ierr);
1377     } else {
1378       ierr = MatView_MPIAIJ_Binary(mat,viewer);CHKERRQ(ierr);
1379     }
1380     PetscFunctionReturn(0);
1381   } else if (isdraw) {
1382     PetscDraw draw;
1383     PetscBool isnull;
1384     ierr = PetscViewerDrawGetDraw(viewer,0,&draw);CHKERRQ(ierr);
1385     ierr = PetscDrawIsNull(draw,&isnull);CHKERRQ(ierr); if (isnull) PetscFunctionReturn(0);
1386   }
1387 
1388   {
1389     /* assemble the entire matrix onto first processor. */
1390     Mat        A;
1391     Mat_SeqAIJ *Aloc;
1392     PetscInt   M = mat->rmap->N,N = mat->cmap->N,m,*ai,*aj,row,*cols,i,*ct;
1393     MatScalar  *a;
1394 
1395     ierr = MatCreate(PetscObjectComm((PetscObject)mat),&A);CHKERRQ(ierr);
1396     if (!rank) {
1397       ierr = MatSetSizes(A,M,N,M,N);CHKERRQ(ierr);
1398     } else {
1399       ierr = MatSetSizes(A,0,0,M,N);CHKERRQ(ierr);
1400     }
1401     /* This is just a temporary matrix, so explicitly using MATMPIAIJ is probably best */
1402     ierr = MatSetType(A,MATMPIAIJ);CHKERRQ(ierr);
1403     ierr = MatMPIAIJSetPreallocation(A,0,NULL,0,NULL);CHKERRQ(ierr);
1404     ierr = MatSetOption(A,MAT_NEW_NONZERO_LOCATION_ERR,PETSC_FALSE);CHKERRQ(ierr);
1405     ierr = PetscLogObjectParent((PetscObject)mat,(PetscObject)A);CHKERRQ(ierr);
1406 
1407     /* copy over the A part */
1408     Aloc = (Mat_SeqAIJ*)aij->A->data;
1409     m    = aij->A->rmap->n; ai = Aloc->i; aj = Aloc->j; a = Aloc->a;
1410     row  = mat->rmap->rstart;
1411     for (i=0; i<ai[m]; i++) aj[i] += mat->cmap->rstart;
1412     for (i=0; i<m; i++) {
1413       ierr = MatSetValues(A,1,&row,ai[i+1]-ai[i],aj,a,INSERT_VALUES);CHKERRQ(ierr);
1414       row++;
1415       a += ai[i+1]-ai[i]; aj += ai[i+1]-ai[i];
1416     }
1417     aj = Aloc->j;
1418     for (i=0; i<ai[m]; i++) aj[i] -= mat->cmap->rstart;
1419 
1420     /* copy over the B part */
1421     Aloc = (Mat_SeqAIJ*)aij->B->data;
1422     m    = aij->B->rmap->n;  ai = Aloc->i; aj = Aloc->j; a = Aloc->a;
1423     row  = mat->rmap->rstart;
1424     ierr = PetscMalloc1(ai[m]+1,&cols);CHKERRQ(ierr);
1425     ct   = cols;
1426     for (i=0; i<ai[m]; i++) cols[i] = aij->garray[aj[i]];
1427     for (i=0; i<m; i++) {
1428       ierr = MatSetValues(A,1,&row,ai[i+1]-ai[i],cols,a,INSERT_VALUES);CHKERRQ(ierr);
1429       row++;
1430       a += ai[i+1]-ai[i]; cols += ai[i+1]-ai[i];
1431     }
1432     ierr = PetscFree(ct);CHKERRQ(ierr);
1433     ierr = MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
1434     ierr = MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
1435     /*
1436        Everyone has to call to draw the matrix since the graphics waits are
1437        synchronized across all processors that share the PetscDraw object
1438     */
1439     ierr = PetscViewerGetSubViewer(viewer,PETSC_COMM_SELF,&sviewer);CHKERRQ(ierr);
1440     if (!rank) {
1441       ierr = PetscObjectSetName((PetscObject)((Mat_MPIAIJ*)(A->data))->A,((PetscObject)mat)->name);CHKERRQ(ierr);
1442       ierr = MatView_SeqAIJ(((Mat_MPIAIJ*)(A->data))->A,sviewer);CHKERRQ(ierr);
1443     }
1444     ierr = PetscViewerRestoreSubViewer(viewer,PETSC_COMM_SELF,&sviewer);CHKERRQ(ierr);
1445     ierr = PetscViewerFlush(viewer);CHKERRQ(ierr);
1446     ierr = MatDestroy(&A);CHKERRQ(ierr);
1447   }
1448   PetscFunctionReturn(0);
1449 }
1450 
1451 #undef __FUNCT__
1452 #define __FUNCT__ "MatView_MPIAIJ"
1453 PetscErrorCode MatView_MPIAIJ(Mat mat,PetscViewer viewer)
1454 {
1455   PetscErrorCode ierr;
1456   PetscBool      iascii,isdraw,issocket,isbinary;
1457 
1458   PetscFunctionBegin;
1459   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERASCII,&iascii);CHKERRQ(ierr);
1460   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERDRAW,&isdraw);CHKERRQ(ierr);
1461   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERBINARY,&isbinary);CHKERRQ(ierr);
1462   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERSOCKET,&issocket);CHKERRQ(ierr);
1463   if (iascii || isdraw || isbinary || issocket) {
1464     ierr = MatView_MPIAIJ_ASCIIorDraworSocket(mat,viewer);CHKERRQ(ierr);
1465   }
1466   PetscFunctionReturn(0);
1467 }
1468 
1469 #undef __FUNCT__
1470 #define __FUNCT__ "MatSOR_MPIAIJ"
1471 PetscErrorCode MatSOR_MPIAIJ(Mat matin,Vec bb,PetscReal omega,MatSORType flag,PetscReal fshift,PetscInt its,PetscInt lits,Vec xx)
1472 {
1473   Mat_MPIAIJ     *mat = (Mat_MPIAIJ*)matin->data;
1474   PetscErrorCode ierr;
1475   Vec            bb1 = 0;
1476   PetscBool      hasop;
1477 
1478   PetscFunctionBegin;
1479   if (flag == SOR_APPLY_UPPER) {
1480     ierr = (*mat->A->ops->sor)(mat->A,bb,omega,flag,fshift,lits,1,xx);CHKERRQ(ierr);
1481     PetscFunctionReturn(0);
1482   }
1483 
1484   if (its > 1 || ~flag & SOR_ZERO_INITIAL_GUESS || flag & SOR_EISENSTAT) {
1485     ierr = VecDuplicate(bb,&bb1);CHKERRQ(ierr);
1486   }
1487 
1488   if ((flag & SOR_LOCAL_SYMMETRIC_SWEEP) == SOR_LOCAL_SYMMETRIC_SWEEP) {
1489     if (flag & SOR_ZERO_INITIAL_GUESS) {
1490       ierr = (*mat->A->ops->sor)(mat->A,bb,omega,flag,fshift,lits,1,xx);CHKERRQ(ierr);
1491       its--;
1492     }
1493 
1494     while (its--) {
1495       ierr = VecScatterBegin(mat->Mvctx,xx,mat->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1496       ierr = VecScatterEnd(mat->Mvctx,xx,mat->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1497 
1498       /* update rhs: bb1 = bb - B*x */
1499       ierr = VecScale(mat->lvec,-1.0);CHKERRQ(ierr);
1500       ierr = (*mat->B->ops->multadd)(mat->B,mat->lvec,bb,bb1);CHKERRQ(ierr);
1501 
1502       /* local sweep */
1503       ierr = (*mat->A->ops->sor)(mat->A,bb1,omega,SOR_SYMMETRIC_SWEEP,fshift,lits,1,xx);CHKERRQ(ierr);
1504     }
1505   } else if (flag & SOR_LOCAL_FORWARD_SWEEP) {
1506     if (flag & SOR_ZERO_INITIAL_GUESS) {
1507       ierr = (*mat->A->ops->sor)(mat->A,bb,omega,flag,fshift,lits,1,xx);CHKERRQ(ierr);
1508       its--;
1509     }
1510     while (its--) {
1511       ierr = VecScatterBegin(mat->Mvctx,xx,mat->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1512       ierr = VecScatterEnd(mat->Mvctx,xx,mat->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1513 
1514       /* update rhs: bb1 = bb - B*x */
1515       ierr = VecScale(mat->lvec,-1.0);CHKERRQ(ierr);
1516       ierr = (*mat->B->ops->multadd)(mat->B,mat->lvec,bb,bb1);CHKERRQ(ierr);
1517 
1518       /* local sweep */
1519       ierr = (*mat->A->ops->sor)(mat->A,bb1,omega,SOR_FORWARD_SWEEP,fshift,lits,1,xx);CHKERRQ(ierr);
1520     }
1521   } else if (flag & SOR_LOCAL_BACKWARD_SWEEP) {
1522     if (flag & SOR_ZERO_INITIAL_GUESS) {
1523       ierr = (*mat->A->ops->sor)(mat->A,bb,omega,flag,fshift,lits,1,xx);CHKERRQ(ierr);
1524       its--;
1525     }
1526     while (its--) {
1527       ierr = VecScatterBegin(mat->Mvctx,xx,mat->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1528       ierr = VecScatterEnd(mat->Mvctx,xx,mat->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1529 
1530       /* update rhs: bb1 = bb - B*x */
1531       ierr = VecScale(mat->lvec,-1.0);CHKERRQ(ierr);
1532       ierr = (*mat->B->ops->multadd)(mat->B,mat->lvec,bb,bb1);CHKERRQ(ierr);
1533 
1534       /* local sweep */
1535       ierr = (*mat->A->ops->sor)(mat->A,bb1,omega,SOR_BACKWARD_SWEEP,fshift,lits,1,xx);CHKERRQ(ierr);
1536     }
1537   } else if (flag & SOR_EISENSTAT) {
1538     Vec xx1;
1539 
1540     ierr = VecDuplicate(bb,&xx1);CHKERRQ(ierr);
1541     ierr = (*mat->A->ops->sor)(mat->A,bb,omega,(MatSORType)(SOR_ZERO_INITIAL_GUESS | SOR_LOCAL_BACKWARD_SWEEP),fshift,lits,1,xx);CHKERRQ(ierr);
1542 
1543     ierr = VecScatterBegin(mat->Mvctx,xx,mat->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1544     ierr = VecScatterEnd(mat->Mvctx,xx,mat->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1545     if (!mat->diag) {
1546       ierr = MatCreateVecs(matin,&mat->diag,NULL);CHKERRQ(ierr);
1547       ierr = MatGetDiagonal(matin,mat->diag);CHKERRQ(ierr);
1548     }
1549     ierr = MatHasOperation(matin,MATOP_MULT_DIAGONAL_BLOCK,&hasop);CHKERRQ(ierr);
1550     if (hasop) {
1551       ierr = MatMultDiagonalBlock(matin,xx,bb1);CHKERRQ(ierr);
1552     } else {
1553       ierr = VecPointwiseMult(bb1,mat->diag,xx);CHKERRQ(ierr);
1554     }
1555     ierr = VecAYPX(bb1,(omega-2.0)/omega,bb);CHKERRQ(ierr);
1556 
1557     ierr = MatMultAdd(mat->B,mat->lvec,bb1,bb1);CHKERRQ(ierr);
1558 
1559     /* local sweep */
1560     ierr = (*mat->A->ops->sor)(mat->A,bb1,omega,(MatSORType)(SOR_ZERO_INITIAL_GUESS | SOR_LOCAL_FORWARD_SWEEP),fshift,lits,1,xx1);CHKERRQ(ierr);
1561     ierr = VecAXPY(xx,1.0,xx1);CHKERRQ(ierr);
1562     ierr = VecDestroy(&xx1);CHKERRQ(ierr);
1563   } else SETERRQ(PetscObjectComm((PetscObject)matin),PETSC_ERR_SUP,"Parallel SOR not supported");
1564 
1565   ierr = VecDestroy(&bb1);CHKERRQ(ierr);
1566   PetscFunctionReturn(0);
1567 }
1568 
1569 #undef __FUNCT__
1570 #define __FUNCT__ "MatPermute_MPIAIJ"
1571 PetscErrorCode MatPermute_MPIAIJ(Mat A,IS rowp,IS colp,Mat *B)
1572 {
1573   Mat            aA,aB,Aperm;
1574   const PetscInt *rwant,*cwant,*gcols,*ai,*bi,*aj,*bj;
1575   PetscScalar    *aa,*ba;
1576   PetscInt       i,j,m,n,ng,anz,bnz,*dnnz,*onnz,*tdnnz,*tonnz,*rdest,*cdest,*work,*gcdest;
1577   PetscSF        rowsf,sf;
1578   IS             parcolp = NULL;
1579   PetscBool      done;
1580   PetscErrorCode ierr;
1581 
1582   PetscFunctionBegin;
1583   ierr = MatGetLocalSize(A,&m,&n);CHKERRQ(ierr);
1584   ierr = ISGetIndices(rowp,&rwant);CHKERRQ(ierr);
1585   ierr = ISGetIndices(colp,&cwant);CHKERRQ(ierr);
1586   ierr = PetscMalloc3(PetscMax(m,n),&work,m,&rdest,n,&cdest);CHKERRQ(ierr);
1587 
1588   /* Invert row permutation to find out where my rows should go */
1589   ierr = PetscSFCreate(PetscObjectComm((PetscObject)A),&rowsf);CHKERRQ(ierr);
1590   ierr = PetscSFSetGraphLayout(rowsf,A->rmap,A->rmap->n,NULL,PETSC_OWN_POINTER,rwant);CHKERRQ(ierr);
1591   ierr = PetscSFSetFromOptions(rowsf);CHKERRQ(ierr);
1592   for (i=0; i<m; i++) work[i] = A->rmap->rstart + i;
1593   ierr = PetscSFReduceBegin(rowsf,MPIU_INT,work,rdest,MPIU_REPLACE);CHKERRQ(ierr);
1594   ierr = PetscSFReduceEnd(rowsf,MPIU_INT,work,rdest,MPIU_REPLACE);CHKERRQ(ierr);
1595 
1596   /* Invert column permutation to find out where my columns should go */
1597   ierr = PetscSFCreate(PetscObjectComm((PetscObject)A),&sf);CHKERRQ(ierr);
1598   ierr = PetscSFSetGraphLayout(sf,A->cmap,A->cmap->n,NULL,PETSC_OWN_POINTER,cwant);CHKERRQ(ierr);
1599   ierr = PetscSFSetFromOptions(sf);CHKERRQ(ierr);
1600   for (i=0; i<n; i++) work[i] = A->cmap->rstart + i;
1601   ierr = PetscSFReduceBegin(sf,MPIU_INT,work,cdest,MPIU_REPLACE);CHKERRQ(ierr);
1602   ierr = PetscSFReduceEnd(sf,MPIU_INT,work,cdest,MPIU_REPLACE);CHKERRQ(ierr);
1603   ierr = PetscSFDestroy(&sf);CHKERRQ(ierr);
1604 
1605   ierr = ISRestoreIndices(rowp,&rwant);CHKERRQ(ierr);
1606   ierr = ISRestoreIndices(colp,&cwant);CHKERRQ(ierr);
1607   ierr = MatMPIAIJGetSeqAIJ(A,&aA,&aB,&gcols);CHKERRQ(ierr);
1608 
1609   /* Find out where my gcols should go */
1610   ierr = MatGetSize(aB,NULL,&ng);CHKERRQ(ierr);
1611   ierr = PetscMalloc1(ng,&gcdest);CHKERRQ(ierr);
1612   ierr = PetscSFCreate(PetscObjectComm((PetscObject)A),&sf);CHKERRQ(ierr);
1613   ierr = PetscSFSetGraphLayout(sf,A->cmap,ng,NULL,PETSC_OWN_POINTER,gcols);CHKERRQ(ierr);
1614   ierr = PetscSFSetFromOptions(sf);CHKERRQ(ierr);
1615   ierr = PetscSFBcastBegin(sf,MPIU_INT,cdest,gcdest);CHKERRQ(ierr);
1616   ierr = PetscSFBcastEnd(sf,MPIU_INT,cdest,gcdest);CHKERRQ(ierr);
1617   ierr = PetscSFDestroy(&sf);CHKERRQ(ierr);
1618 
1619   ierr = PetscCalloc4(m,&dnnz,m,&onnz,m,&tdnnz,m,&tonnz);CHKERRQ(ierr);
1620   ierr = MatGetRowIJ(aA,0,PETSC_FALSE,PETSC_FALSE,&anz,&ai,&aj,&done);CHKERRQ(ierr);
1621   ierr = MatGetRowIJ(aB,0,PETSC_FALSE,PETSC_FALSE,&bnz,&bi,&bj,&done);CHKERRQ(ierr);
1622   for (i=0; i<m; i++) {
1623     PetscInt row = rdest[i],rowner;
1624     ierr = PetscLayoutFindOwner(A->rmap,row,&rowner);CHKERRQ(ierr);
1625     for (j=ai[i]; j<ai[i+1]; j++) {
1626       PetscInt cowner,col = cdest[aj[j]];
1627       ierr = PetscLayoutFindOwner(A->cmap,col,&cowner);CHKERRQ(ierr); /* Could build an index for the columns to eliminate this search */
1628       if (rowner == cowner) dnnz[i]++;
1629       else onnz[i]++;
1630     }
1631     for (j=bi[i]; j<bi[i+1]; j++) {
1632       PetscInt cowner,col = gcdest[bj[j]];
1633       ierr = PetscLayoutFindOwner(A->cmap,col,&cowner);CHKERRQ(ierr);
1634       if (rowner == cowner) dnnz[i]++;
1635       else onnz[i]++;
1636     }
1637   }
1638   ierr = PetscSFBcastBegin(rowsf,MPIU_INT,dnnz,tdnnz);CHKERRQ(ierr);
1639   ierr = PetscSFBcastEnd(rowsf,MPIU_INT,dnnz,tdnnz);CHKERRQ(ierr);
1640   ierr = PetscSFBcastBegin(rowsf,MPIU_INT,onnz,tonnz);CHKERRQ(ierr);
1641   ierr = PetscSFBcastEnd(rowsf,MPIU_INT,onnz,tonnz);CHKERRQ(ierr);
1642   ierr = PetscSFDestroy(&rowsf);CHKERRQ(ierr);
1643 
1644   ierr = MatCreateAIJ(PetscObjectComm((PetscObject)A),A->rmap->n,A->cmap->n,A->rmap->N,A->cmap->N,0,tdnnz,0,tonnz,&Aperm);CHKERRQ(ierr);
1645   ierr = MatSeqAIJGetArray(aA,&aa);CHKERRQ(ierr);
1646   ierr = MatSeqAIJGetArray(aB,&ba);CHKERRQ(ierr);
1647   for (i=0; i<m; i++) {
1648     PetscInt *acols = dnnz,*bcols = onnz; /* Repurpose now-unneeded arrays */
1649     PetscInt j0,rowlen;
1650     rowlen = ai[i+1] - ai[i];
1651     for (j0=j=0; j<rowlen; j0=j) { /* rowlen could be larger than number of rows m, so sum in batches */
1652       for ( ; j<PetscMin(rowlen,j0+m); j++) acols[j-j0] = cdest[aj[ai[i]+j]];
1653       ierr = MatSetValues(Aperm,1,&rdest[i],j-j0,acols,aa+ai[i]+j0,INSERT_VALUES);CHKERRQ(ierr);
1654     }
1655     rowlen = bi[i+1] - bi[i];
1656     for (j0=j=0; j<rowlen; j0=j) {
1657       for ( ; j<PetscMin(rowlen,j0+m); j++) bcols[j-j0] = gcdest[bj[bi[i]+j]];
1658       ierr = MatSetValues(Aperm,1,&rdest[i],j-j0,bcols,ba+bi[i]+j0,INSERT_VALUES);CHKERRQ(ierr);
1659     }
1660   }
1661   ierr = MatAssemblyBegin(Aperm,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
1662   ierr = MatAssemblyEnd(Aperm,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
1663   ierr = MatRestoreRowIJ(aA,0,PETSC_FALSE,PETSC_FALSE,&anz,&ai,&aj,&done);CHKERRQ(ierr);
1664   ierr = MatRestoreRowIJ(aB,0,PETSC_FALSE,PETSC_FALSE,&bnz,&bi,&bj,&done);CHKERRQ(ierr);
1665   ierr = MatSeqAIJRestoreArray(aA,&aa);CHKERRQ(ierr);
1666   ierr = MatSeqAIJRestoreArray(aB,&ba);CHKERRQ(ierr);
1667   ierr = PetscFree4(dnnz,onnz,tdnnz,tonnz);CHKERRQ(ierr);
1668   ierr = PetscFree3(work,rdest,cdest);CHKERRQ(ierr);
1669   ierr = PetscFree(gcdest);CHKERRQ(ierr);
1670   if (parcolp) {ierr = ISDestroy(&colp);CHKERRQ(ierr);}
1671   *B = Aperm;
1672   PetscFunctionReturn(0);
1673 }
1674 
1675 #undef __FUNCT__
1676 #define __FUNCT__ "MatGetGhosts_MPIAIJ"
1677 PetscErrorCode  MatGetGhosts_MPIAIJ(Mat mat,PetscInt *nghosts,const PetscInt *ghosts[])
1678 {
1679   Mat_MPIAIJ *aij = (Mat_MPIAIJ*)mat->data;
1680   PetscErrorCode ierr;
1681 
1682   PetscFunctionBegin;
1683   ierr = MatGetSize(aij->B,NULL,nghosts);CHKERRQ(ierr);
1684   if (ghosts) *ghosts = aij->garray;
1685   PetscFunctionReturn(0);
1686 }
1687 
1688 #undef __FUNCT__
1689 #define __FUNCT__ "MatGetInfo_MPIAIJ"
1690 PetscErrorCode MatGetInfo_MPIAIJ(Mat matin,MatInfoType flag,MatInfo *info)
1691 {
1692   Mat_MPIAIJ     *mat = (Mat_MPIAIJ*)matin->data;
1693   Mat            A    = mat->A,B = mat->B;
1694   PetscErrorCode ierr;
1695   PetscReal      isend[5],irecv[5];
1696 
1697   PetscFunctionBegin;
1698   info->block_size = 1.0;
1699   ierr             = MatGetInfo(A,MAT_LOCAL,info);CHKERRQ(ierr);
1700 
1701   isend[0] = info->nz_used; isend[1] = info->nz_allocated; isend[2] = info->nz_unneeded;
1702   isend[3] = info->memory;  isend[4] = info->mallocs;
1703 
1704   ierr = MatGetInfo(B,MAT_LOCAL,info);CHKERRQ(ierr);
1705 
1706   isend[0] += info->nz_used; isend[1] += info->nz_allocated; isend[2] += info->nz_unneeded;
1707   isend[3] += info->memory;  isend[4] += info->mallocs;
1708   if (flag == MAT_LOCAL) {
1709     info->nz_used      = isend[0];
1710     info->nz_allocated = isend[1];
1711     info->nz_unneeded  = isend[2];
1712     info->memory       = isend[3];
1713     info->mallocs      = isend[4];
1714   } else if (flag == MAT_GLOBAL_MAX) {
1715     ierr = MPIU_Allreduce(isend,irecv,5,MPIU_REAL,MPIU_MAX,PetscObjectComm((PetscObject)matin));CHKERRQ(ierr);
1716 
1717     info->nz_used      = irecv[0];
1718     info->nz_allocated = irecv[1];
1719     info->nz_unneeded  = irecv[2];
1720     info->memory       = irecv[3];
1721     info->mallocs      = irecv[4];
1722   } else if (flag == MAT_GLOBAL_SUM) {
1723     ierr = MPIU_Allreduce(isend,irecv,5,MPIU_REAL,MPIU_SUM,PetscObjectComm((PetscObject)matin));CHKERRQ(ierr);
1724 
1725     info->nz_used      = irecv[0];
1726     info->nz_allocated = irecv[1];
1727     info->nz_unneeded  = irecv[2];
1728     info->memory       = irecv[3];
1729     info->mallocs      = irecv[4];
1730   }
1731   info->fill_ratio_given  = 0; /* no parallel LU/ILU/Cholesky */
1732   info->fill_ratio_needed = 0;
1733   info->factor_mallocs    = 0;
1734   PetscFunctionReturn(0);
1735 }
1736 
1737 #undef __FUNCT__
1738 #define __FUNCT__ "MatSetOption_MPIAIJ"
1739 PetscErrorCode MatSetOption_MPIAIJ(Mat A,MatOption op,PetscBool flg)
1740 {
1741   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
1742   PetscErrorCode ierr;
1743 
1744   PetscFunctionBegin;
1745   switch (op) {
1746   case MAT_NEW_NONZERO_LOCATIONS:
1747   case MAT_NEW_NONZERO_ALLOCATION_ERR:
1748   case MAT_UNUSED_NONZERO_LOCATION_ERR:
1749   case MAT_KEEP_NONZERO_PATTERN:
1750   case MAT_NEW_NONZERO_LOCATION_ERR:
1751   case MAT_USE_INODES:
1752   case MAT_IGNORE_ZERO_ENTRIES:
1753     MatCheckPreallocated(A,1);
1754     ierr = MatSetOption(a->A,op,flg);CHKERRQ(ierr);
1755     ierr = MatSetOption(a->B,op,flg);CHKERRQ(ierr);
1756     break;
1757   case MAT_ROW_ORIENTED:
1758     a->roworiented = flg;
1759 
1760     ierr = MatSetOption(a->A,op,flg);CHKERRQ(ierr);
1761     ierr = MatSetOption(a->B,op,flg);CHKERRQ(ierr);
1762     break;
1763   case MAT_NEW_DIAGONALS:
1764     ierr = PetscInfo1(A,"Option %s ignored\n",MatOptions[op]);CHKERRQ(ierr);
1765     break;
1766   case MAT_IGNORE_OFF_PROC_ENTRIES:
1767     a->donotstash = flg;
1768     break;
1769   case MAT_SPD:
1770     A->spd_set = PETSC_TRUE;
1771     A->spd     = flg;
1772     if (flg) {
1773       A->symmetric                  = PETSC_TRUE;
1774       A->structurally_symmetric     = PETSC_TRUE;
1775       A->symmetric_set              = PETSC_TRUE;
1776       A->structurally_symmetric_set = PETSC_TRUE;
1777     }
1778     break;
1779   case MAT_SYMMETRIC:
1780     ierr = MatSetOption(a->A,op,flg);CHKERRQ(ierr);
1781     break;
1782   case MAT_STRUCTURALLY_SYMMETRIC:
1783     ierr = MatSetOption(a->A,op,flg);CHKERRQ(ierr);
1784     break;
1785   case MAT_HERMITIAN:
1786     ierr = MatSetOption(a->A,op,flg);CHKERRQ(ierr);
1787     break;
1788   case MAT_SYMMETRY_ETERNAL:
1789     ierr = MatSetOption(a->A,op,flg);CHKERRQ(ierr);
1790     break;
1791   default:
1792     SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_SUP,"unknown option %d",op);
1793   }
1794   PetscFunctionReturn(0);
1795 }
1796 
1797 #undef __FUNCT__
1798 #define __FUNCT__ "MatGetRow_MPIAIJ"
1799 PetscErrorCode MatGetRow_MPIAIJ(Mat matin,PetscInt row,PetscInt *nz,PetscInt **idx,PetscScalar **v)
1800 {
1801   Mat_MPIAIJ     *mat = (Mat_MPIAIJ*)matin->data;
1802   PetscScalar    *vworkA,*vworkB,**pvA,**pvB,*v_p;
1803   PetscErrorCode ierr;
1804   PetscInt       i,*cworkA,*cworkB,**pcA,**pcB,cstart = matin->cmap->rstart;
1805   PetscInt       nztot,nzA,nzB,lrow,rstart = matin->rmap->rstart,rend = matin->rmap->rend;
1806   PetscInt       *cmap,*idx_p;
1807 
1808   PetscFunctionBegin;
1809   if (mat->getrowactive) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"Already active");
1810   mat->getrowactive = PETSC_TRUE;
1811 
1812   if (!mat->rowvalues && (idx || v)) {
1813     /*
1814         allocate enough space to hold information from the longest row.
1815     */
1816     Mat_SeqAIJ *Aa = (Mat_SeqAIJ*)mat->A->data,*Ba = (Mat_SeqAIJ*)mat->B->data;
1817     PetscInt   max = 1,tmp;
1818     for (i=0; i<matin->rmap->n; i++) {
1819       tmp = Aa->i[i+1] - Aa->i[i] + Ba->i[i+1] - Ba->i[i];
1820       if (max < tmp) max = tmp;
1821     }
1822     ierr = PetscMalloc2(max,&mat->rowvalues,max,&mat->rowindices);CHKERRQ(ierr);
1823   }
1824 
1825   if (row < rstart || row >= rend) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Only local rows");
1826   lrow = row - rstart;
1827 
1828   pvA = &vworkA; pcA = &cworkA; pvB = &vworkB; pcB = &cworkB;
1829   if (!v)   {pvA = 0; pvB = 0;}
1830   if (!idx) {pcA = 0; if (!v) pcB = 0;}
1831   ierr  = (*mat->A->ops->getrow)(mat->A,lrow,&nzA,pcA,pvA);CHKERRQ(ierr);
1832   ierr  = (*mat->B->ops->getrow)(mat->B,lrow,&nzB,pcB,pvB);CHKERRQ(ierr);
1833   nztot = nzA + nzB;
1834 
1835   cmap = mat->garray;
1836   if (v  || idx) {
1837     if (nztot) {
1838       /* Sort by increasing column numbers, assuming A and B already sorted */
1839       PetscInt imark = -1;
1840       if (v) {
1841         *v = v_p = mat->rowvalues;
1842         for (i=0; i<nzB; i++) {
1843           if (cmap[cworkB[i]] < cstart) v_p[i] = vworkB[i];
1844           else break;
1845         }
1846         imark = i;
1847         for (i=0; i<nzA; i++)     v_p[imark+i] = vworkA[i];
1848         for (i=imark; i<nzB; i++) v_p[nzA+i]   = vworkB[i];
1849       }
1850       if (idx) {
1851         *idx = idx_p = mat->rowindices;
1852         if (imark > -1) {
1853           for (i=0; i<imark; i++) {
1854             idx_p[i] = cmap[cworkB[i]];
1855           }
1856         } else {
1857           for (i=0; i<nzB; i++) {
1858             if (cmap[cworkB[i]] < cstart) idx_p[i] = cmap[cworkB[i]];
1859             else break;
1860           }
1861           imark = i;
1862         }
1863         for (i=0; i<nzA; i++)     idx_p[imark+i] = cstart + cworkA[i];
1864         for (i=imark; i<nzB; i++) idx_p[nzA+i]   = cmap[cworkB[i]];
1865       }
1866     } else {
1867       if (idx) *idx = 0;
1868       if (v)   *v   = 0;
1869     }
1870   }
1871   *nz  = nztot;
1872   ierr = (*mat->A->ops->restorerow)(mat->A,lrow,&nzA,pcA,pvA);CHKERRQ(ierr);
1873   ierr = (*mat->B->ops->restorerow)(mat->B,lrow,&nzB,pcB,pvB);CHKERRQ(ierr);
1874   PetscFunctionReturn(0);
1875 }
1876 
1877 #undef __FUNCT__
1878 #define __FUNCT__ "MatRestoreRow_MPIAIJ"
1879 PetscErrorCode MatRestoreRow_MPIAIJ(Mat mat,PetscInt row,PetscInt *nz,PetscInt **idx,PetscScalar **v)
1880 {
1881   Mat_MPIAIJ *aij = (Mat_MPIAIJ*)mat->data;
1882 
1883   PetscFunctionBegin;
1884   if (!aij->getrowactive) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"MatGetRow() must be called first");
1885   aij->getrowactive = PETSC_FALSE;
1886   PetscFunctionReturn(0);
1887 }
1888 
1889 #undef __FUNCT__
1890 #define __FUNCT__ "MatNorm_MPIAIJ"
1891 PetscErrorCode MatNorm_MPIAIJ(Mat mat,NormType type,PetscReal *norm)
1892 {
1893   Mat_MPIAIJ     *aij  = (Mat_MPIAIJ*)mat->data;
1894   Mat_SeqAIJ     *amat = (Mat_SeqAIJ*)aij->A->data,*bmat = (Mat_SeqAIJ*)aij->B->data;
1895   PetscErrorCode ierr;
1896   PetscInt       i,j,cstart = mat->cmap->rstart;
1897   PetscReal      sum = 0.0;
1898   MatScalar      *v;
1899 
1900   PetscFunctionBegin;
1901   if (aij->size == 1) {
1902     ierr =  MatNorm(aij->A,type,norm);CHKERRQ(ierr);
1903   } else {
1904     if (type == NORM_FROBENIUS) {
1905       v = amat->a;
1906       for (i=0; i<amat->nz; i++) {
1907         sum += PetscRealPart(PetscConj(*v)*(*v)); v++;
1908       }
1909       v = bmat->a;
1910       for (i=0; i<bmat->nz; i++) {
1911         sum += PetscRealPart(PetscConj(*v)*(*v)); v++;
1912       }
1913       ierr  = MPIU_Allreduce(&sum,norm,1,MPIU_REAL,MPIU_SUM,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1914       *norm = PetscSqrtReal(*norm);
1915     } else if (type == NORM_1) { /* max column norm */
1916       PetscReal *tmp,*tmp2;
1917       PetscInt  *jj,*garray = aij->garray;
1918       ierr  = PetscCalloc1(mat->cmap->N+1,&tmp);CHKERRQ(ierr);
1919       ierr  = PetscMalloc1(mat->cmap->N+1,&tmp2);CHKERRQ(ierr);
1920       *norm = 0.0;
1921       v     = amat->a; jj = amat->j;
1922       for (j=0; j<amat->nz; j++) {
1923         tmp[cstart + *jj++] += PetscAbsScalar(*v);  v++;
1924       }
1925       v = bmat->a; jj = bmat->j;
1926       for (j=0; j<bmat->nz; j++) {
1927         tmp[garray[*jj++]] += PetscAbsScalar(*v); v++;
1928       }
1929       ierr = MPIU_Allreduce(tmp,tmp2,mat->cmap->N,MPIU_REAL,MPIU_SUM,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1930       for (j=0; j<mat->cmap->N; j++) {
1931         if (tmp2[j] > *norm) *norm = tmp2[j];
1932       }
1933       ierr = PetscFree(tmp);CHKERRQ(ierr);
1934       ierr = PetscFree(tmp2);CHKERRQ(ierr);
1935     } else if (type == NORM_INFINITY) { /* max row norm */
1936       PetscReal ntemp = 0.0;
1937       for (j=0; j<aij->A->rmap->n; j++) {
1938         v   = amat->a + amat->i[j];
1939         sum = 0.0;
1940         for (i=0; i<amat->i[j+1]-amat->i[j]; i++) {
1941           sum += PetscAbsScalar(*v); v++;
1942         }
1943         v = bmat->a + bmat->i[j];
1944         for (i=0; i<bmat->i[j+1]-bmat->i[j]; i++) {
1945           sum += PetscAbsScalar(*v); v++;
1946         }
1947         if (sum > ntemp) ntemp = sum;
1948       }
1949       ierr = MPIU_Allreduce(&ntemp,norm,1,MPIU_REAL,MPIU_MAX,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1950     } else SETERRQ(PetscObjectComm((PetscObject)mat),PETSC_ERR_SUP,"No support for two norm");
1951   }
1952   PetscFunctionReturn(0);
1953 }
1954 
1955 #undef __FUNCT__
1956 #define __FUNCT__ "MatTranspose_MPIAIJ"
1957 PetscErrorCode MatTranspose_MPIAIJ(Mat A,MatReuse reuse,Mat *matout)
1958 {
1959   Mat_MPIAIJ     *a   = (Mat_MPIAIJ*)A->data;
1960   Mat_SeqAIJ     *Aloc=(Mat_SeqAIJ*)a->A->data,*Bloc=(Mat_SeqAIJ*)a->B->data;
1961   PetscErrorCode ierr;
1962   PetscInt       M      = A->rmap->N,N = A->cmap->N,ma,na,mb,nb,*ai,*aj,*bi,*bj,row,*cols,*cols_tmp,i;
1963   PetscInt       cstart = A->cmap->rstart,ncol;
1964   Mat            B;
1965   MatScalar      *array;
1966 
1967   PetscFunctionBegin;
1968   if (reuse == MAT_REUSE_MATRIX && A == *matout && M != N) SETERRQ(PetscObjectComm((PetscObject)A),PETSC_ERR_ARG_SIZ,"Square matrix only for in-place");
1969 
1970   ma = A->rmap->n; na = A->cmap->n; mb = a->B->rmap->n; nb = a->B->cmap->n;
1971   ai = Aloc->i; aj = Aloc->j;
1972   bi = Bloc->i; bj = Bloc->j;
1973   if (reuse == MAT_INITIAL_MATRIX || *matout == A) {
1974     PetscInt             *d_nnz,*g_nnz,*o_nnz;
1975     PetscSFNode          *oloc;
1976     PETSC_UNUSED PetscSF sf;
1977 
1978     ierr = PetscMalloc4(na,&d_nnz,na,&o_nnz,nb,&g_nnz,nb,&oloc);CHKERRQ(ierr);
1979     /* compute d_nnz for preallocation */
1980     ierr = PetscMemzero(d_nnz,na*sizeof(PetscInt));CHKERRQ(ierr);
1981     for (i=0; i<ai[ma]; i++) {
1982       d_nnz[aj[i]]++;
1983       aj[i] += cstart; /* global col index to be used by MatSetValues() */
1984     }
1985     /* compute local off-diagonal contributions */
1986     ierr = PetscMemzero(g_nnz,nb*sizeof(PetscInt));CHKERRQ(ierr);
1987     for (i=0; i<bi[ma]; i++) g_nnz[bj[i]]++;
1988     /* map those to global */
1989     ierr = PetscSFCreate(PetscObjectComm((PetscObject)A),&sf);CHKERRQ(ierr);
1990     ierr = PetscSFSetGraphLayout(sf,A->cmap,nb,NULL,PETSC_USE_POINTER,a->garray);CHKERRQ(ierr);
1991     ierr = PetscSFSetFromOptions(sf);CHKERRQ(ierr);
1992     ierr = PetscMemzero(o_nnz,na*sizeof(PetscInt));CHKERRQ(ierr);
1993     ierr = PetscSFReduceBegin(sf,MPIU_INT,g_nnz,o_nnz,MPIU_SUM);CHKERRQ(ierr);
1994     ierr = PetscSFReduceEnd(sf,MPIU_INT,g_nnz,o_nnz,MPIU_SUM);CHKERRQ(ierr);
1995     ierr = PetscSFDestroy(&sf);CHKERRQ(ierr);
1996 
1997     ierr = MatCreate(PetscObjectComm((PetscObject)A),&B);CHKERRQ(ierr);
1998     ierr = MatSetSizes(B,A->cmap->n,A->rmap->n,N,M);CHKERRQ(ierr);
1999     ierr = MatSetBlockSizes(B,PetscAbs(A->cmap->bs),PetscAbs(A->rmap->bs));CHKERRQ(ierr);
2000     ierr = MatSetType(B,((PetscObject)A)->type_name);CHKERRQ(ierr);
2001     ierr = MatMPIAIJSetPreallocation(B,0,d_nnz,0,o_nnz);CHKERRQ(ierr);
2002     ierr = PetscFree4(d_nnz,o_nnz,g_nnz,oloc);CHKERRQ(ierr);
2003   } else {
2004     B    = *matout;
2005     ierr = MatSetOption(B,MAT_NEW_NONZERO_ALLOCATION_ERR,PETSC_TRUE);CHKERRQ(ierr);
2006     for (i=0; i<ai[ma]; i++) aj[i] += cstart; /* global col index to be used by MatSetValues() */
2007   }
2008 
2009   /* copy over the A part */
2010   array = Aloc->a;
2011   row   = A->rmap->rstart;
2012   for (i=0; i<ma; i++) {
2013     ncol = ai[i+1]-ai[i];
2014     ierr = MatSetValues(B,ncol,aj,1,&row,array,INSERT_VALUES);CHKERRQ(ierr);
2015     row++;
2016     array += ncol; aj += ncol;
2017   }
2018   aj = Aloc->j;
2019   for (i=0; i<ai[ma]; i++) aj[i] -= cstart; /* resume local col index */
2020 
2021   /* copy over the B part */
2022   ierr  = PetscCalloc1(bi[mb],&cols);CHKERRQ(ierr);
2023   array = Bloc->a;
2024   row   = A->rmap->rstart;
2025   for (i=0; i<bi[mb]; i++) cols[i] = a->garray[bj[i]];
2026   cols_tmp = cols;
2027   for (i=0; i<mb; i++) {
2028     ncol = bi[i+1]-bi[i];
2029     ierr = MatSetValues(B,ncol,cols_tmp,1,&row,array,INSERT_VALUES);CHKERRQ(ierr);
2030     row++;
2031     array += ncol; cols_tmp += ncol;
2032   }
2033   ierr = PetscFree(cols);CHKERRQ(ierr);
2034 
2035   ierr = MatAssemblyBegin(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
2036   ierr = MatAssemblyEnd(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
2037   if (reuse == MAT_INITIAL_MATRIX || *matout != A) {
2038     *matout = B;
2039   } else {
2040     ierr = MatHeaderMerge(A,&B);CHKERRQ(ierr);
2041   }
2042   PetscFunctionReturn(0);
2043 }
2044 
2045 #undef __FUNCT__
2046 #define __FUNCT__ "MatDiagonalScale_MPIAIJ"
2047 PetscErrorCode MatDiagonalScale_MPIAIJ(Mat mat,Vec ll,Vec rr)
2048 {
2049   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
2050   Mat            a    = aij->A,b = aij->B;
2051   PetscErrorCode ierr;
2052   PetscInt       s1,s2,s3;
2053 
2054   PetscFunctionBegin;
2055   ierr = MatGetLocalSize(mat,&s2,&s3);CHKERRQ(ierr);
2056   if (rr) {
2057     ierr = VecGetLocalSize(rr,&s1);CHKERRQ(ierr);
2058     if (s1!=s3) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_SIZ,"right vector non-conforming local size");
2059     /* Overlap communication with computation. */
2060     ierr = VecScatterBegin(aij->Mvctx,rr,aij->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
2061   }
2062   if (ll) {
2063     ierr = VecGetLocalSize(ll,&s1);CHKERRQ(ierr);
2064     if (s1!=s2) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_SIZ,"left vector non-conforming local size");
2065     ierr = (*b->ops->diagonalscale)(b,ll,0);CHKERRQ(ierr);
2066   }
2067   /* scale  the diagonal block */
2068   ierr = (*a->ops->diagonalscale)(a,ll,rr);CHKERRQ(ierr);
2069 
2070   if (rr) {
2071     /* Do a scatter end and then right scale the off-diagonal block */
2072     ierr = VecScatterEnd(aij->Mvctx,rr,aij->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
2073     ierr = (*b->ops->diagonalscale)(b,0,aij->lvec);CHKERRQ(ierr);
2074   }
2075   PetscFunctionReturn(0);
2076 }
2077 
2078 #undef __FUNCT__
2079 #define __FUNCT__ "MatSetUnfactored_MPIAIJ"
2080 PetscErrorCode MatSetUnfactored_MPIAIJ(Mat A)
2081 {
2082   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
2083   PetscErrorCode ierr;
2084 
2085   PetscFunctionBegin;
2086   ierr = MatSetUnfactored(a->A);CHKERRQ(ierr);
2087   PetscFunctionReturn(0);
2088 }
2089 
2090 #undef __FUNCT__
2091 #define __FUNCT__ "MatEqual_MPIAIJ"
2092 PetscErrorCode MatEqual_MPIAIJ(Mat A,Mat B,PetscBool  *flag)
2093 {
2094   Mat_MPIAIJ     *matB = (Mat_MPIAIJ*)B->data,*matA = (Mat_MPIAIJ*)A->data;
2095   Mat            a,b,c,d;
2096   PetscBool      flg;
2097   PetscErrorCode ierr;
2098 
2099   PetscFunctionBegin;
2100   a = matA->A; b = matA->B;
2101   c = matB->A; d = matB->B;
2102 
2103   ierr = MatEqual(a,c,&flg);CHKERRQ(ierr);
2104   if (flg) {
2105     ierr = MatEqual(b,d,&flg);CHKERRQ(ierr);
2106   }
2107   ierr = MPIU_Allreduce(&flg,flag,1,MPIU_BOOL,MPI_LAND,PetscObjectComm((PetscObject)A));CHKERRQ(ierr);
2108   PetscFunctionReturn(0);
2109 }
2110 
2111 #undef __FUNCT__
2112 #define __FUNCT__ "MatCopy_MPIAIJ"
2113 PetscErrorCode MatCopy_MPIAIJ(Mat A,Mat B,MatStructure str)
2114 {
2115   PetscErrorCode ierr;
2116   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
2117   Mat_MPIAIJ     *b = (Mat_MPIAIJ*)B->data;
2118 
2119   PetscFunctionBegin;
2120   /* If the two matrices don't have the same copy implementation, they aren't compatible for fast copy. */
2121   if ((str != SAME_NONZERO_PATTERN) || (A->ops->copy != B->ops->copy)) {
2122     /* because of the column compression in the off-processor part of the matrix a->B,
2123        the number of columns in a->B and b->B may be different, hence we cannot call
2124        the MatCopy() directly on the two parts. If need be, we can provide a more
2125        efficient copy than the MatCopy_Basic() by first uncompressing the a->B matrices
2126        then copying the submatrices */
2127     ierr = MatCopy_Basic(A,B,str);CHKERRQ(ierr);
2128   } else {
2129     ierr = MatCopy(a->A,b->A,str);CHKERRQ(ierr);
2130     ierr = MatCopy(a->B,b->B,str);CHKERRQ(ierr);
2131   }
2132   PetscFunctionReturn(0);
2133 }
2134 
2135 #undef __FUNCT__
2136 #define __FUNCT__ "MatSetUp_MPIAIJ"
2137 PetscErrorCode MatSetUp_MPIAIJ(Mat A)
2138 {
2139   PetscErrorCode ierr;
2140 
2141   PetscFunctionBegin;
2142   ierr =  MatMPIAIJSetPreallocation(A,PETSC_DEFAULT,0,PETSC_DEFAULT,0);CHKERRQ(ierr);
2143   PetscFunctionReturn(0);
2144 }
2145 
2146 /*
2147    Computes the number of nonzeros per row needed for preallocation when X and Y
2148    have different nonzero structure.
2149 */
2150 #undef __FUNCT__
2151 #define __FUNCT__ "MatAXPYGetPreallocation_MPIX_private"
2152 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)
2153 {
2154   PetscInt       i,j,k,nzx,nzy;
2155 
2156   PetscFunctionBegin;
2157   /* Set the number of nonzeros in the new matrix */
2158   for (i=0; i<m; i++) {
2159     const PetscInt *xjj = xj+xi[i],*yjj = yj+yi[i];
2160     nzx = xi[i+1] - xi[i];
2161     nzy = yi[i+1] - yi[i];
2162     nnz[i] = 0;
2163     for (j=0,k=0; j<nzx; j++) {                   /* Point in X */
2164       for (; k<nzy && yltog[yjj[k]]<xltog[xjj[j]]; k++) nnz[i]++; /* Catch up to X */
2165       if (k<nzy && yltog[yjj[k]]==xltog[xjj[j]]) k++;             /* Skip duplicate */
2166       nnz[i]++;
2167     }
2168     for (; k<nzy; k++) nnz[i]++;
2169   }
2170   PetscFunctionReturn(0);
2171 }
2172 
2173 /* This is the same as MatAXPYGetPreallocation_SeqAIJ, except that the local-to-global map is provided */
2174 #undef __FUNCT__
2175 #define __FUNCT__ "MatAXPYGetPreallocation_MPIAIJ"
2176 static PetscErrorCode MatAXPYGetPreallocation_MPIAIJ(Mat Y,const PetscInt *yltog,Mat X,const PetscInt *xltog,PetscInt *nnz)
2177 {
2178   PetscErrorCode ierr;
2179   PetscInt       m = Y->rmap->N;
2180   Mat_SeqAIJ     *x = (Mat_SeqAIJ*)X->data;
2181   Mat_SeqAIJ     *y = (Mat_SeqAIJ*)Y->data;
2182 
2183   PetscFunctionBegin;
2184   ierr = MatAXPYGetPreallocation_MPIX_private(m,x->i,x->j,xltog,y->i,y->j,yltog,nnz);CHKERRQ(ierr);
2185   PetscFunctionReturn(0);
2186 }
2187 
2188 #undef __FUNCT__
2189 #define __FUNCT__ "MatAXPY_MPIAIJ"
2190 PetscErrorCode MatAXPY_MPIAIJ(Mat Y,PetscScalar a,Mat X,MatStructure str)
2191 {
2192   PetscErrorCode ierr;
2193   Mat_MPIAIJ     *xx = (Mat_MPIAIJ*)X->data,*yy = (Mat_MPIAIJ*)Y->data;
2194   PetscBLASInt   bnz,one=1;
2195   Mat_SeqAIJ     *x,*y;
2196 
2197   PetscFunctionBegin;
2198   if (str == SAME_NONZERO_PATTERN) {
2199     PetscScalar alpha = a;
2200     x    = (Mat_SeqAIJ*)xx->A->data;
2201     ierr = PetscBLASIntCast(x->nz,&bnz);CHKERRQ(ierr);
2202     y    = (Mat_SeqAIJ*)yy->A->data;
2203     PetscStackCallBLAS("BLASaxpy",BLASaxpy_(&bnz,&alpha,x->a,&one,y->a,&one));
2204     x    = (Mat_SeqAIJ*)xx->B->data;
2205     y    = (Mat_SeqAIJ*)yy->B->data;
2206     ierr = PetscBLASIntCast(x->nz,&bnz);CHKERRQ(ierr);
2207     PetscStackCallBLAS("BLASaxpy",BLASaxpy_(&bnz,&alpha,x->a,&one,y->a,&one));
2208     ierr = PetscObjectStateIncrease((PetscObject)Y);CHKERRQ(ierr);
2209   } else if (str == SUBSET_NONZERO_PATTERN) { /* nonzeros of X is a subset of Y's */
2210     ierr = MatAXPY_Basic(Y,a,X,str);CHKERRQ(ierr);
2211   } else {
2212     Mat      B;
2213     PetscInt *nnz_d,*nnz_o;
2214     ierr = PetscMalloc1(yy->A->rmap->N,&nnz_d);CHKERRQ(ierr);
2215     ierr = PetscMalloc1(yy->B->rmap->N,&nnz_o);CHKERRQ(ierr);
2216     ierr = MatCreate(PetscObjectComm((PetscObject)Y),&B);CHKERRQ(ierr);
2217     ierr = PetscObjectSetName((PetscObject)B,((PetscObject)Y)->name);CHKERRQ(ierr);
2218     ierr = MatSetSizes(B,Y->rmap->n,Y->cmap->n,Y->rmap->N,Y->cmap->N);CHKERRQ(ierr);
2219     ierr = MatSetBlockSizesFromMats(B,Y,Y);CHKERRQ(ierr);
2220     ierr = MatSetType(B,MATMPIAIJ);CHKERRQ(ierr);
2221     ierr = MatAXPYGetPreallocation_SeqAIJ(yy->A,xx->A,nnz_d);CHKERRQ(ierr);
2222     ierr = MatAXPYGetPreallocation_MPIAIJ(yy->B,yy->garray,xx->B,xx->garray,nnz_o);CHKERRQ(ierr);
2223     ierr = MatMPIAIJSetPreallocation(B,0,nnz_d,0,nnz_o);CHKERRQ(ierr);
2224     ierr = MatAXPY_BasicWithPreallocation(B,Y,a,X,str);CHKERRQ(ierr);
2225     ierr = MatHeaderReplace(Y,&B);CHKERRQ(ierr);
2226     ierr = PetscFree(nnz_d);CHKERRQ(ierr);
2227     ierr = PetscFree(nnz_o);CHKERRQ(ierr);
2228   }
2229   PetscFunctionReturn(0);
2230 }
2231 
2232 extern PetscErrorCode  MatConjugate_SeqAIJ(Mat);
2233 
2234 #undef __FUNCT__
2235 #define __FUNCT__ "MatConjugate_MPIAIJ"
2236 PetscErrorCode  MatConjugate_MPIAIJ(Mat mat)
2237 {
2238 #if defined(PETSC_USE_COMPLEX)
2239   PetscErrorCode ierr;
2240   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
2241 
2242   PetscFunctionBegin;
2243   ierr = MatConjugate_SeqAIJ(aij->A);CHKERRQ(ierr);
2244   ierr = MatConjugate_SeqAIJ(aij->B);CHKERRQ(ierr);
2245 #else
2246   PetscFunctionBegin;
2247 #endif
2248   PetscFunctionReturn(0);
2249 }
2250 
2251 #undef __FUNCT__
2252 #define __FUNCT__ "MatRealPart_MPIAIJ"
2253 PetscErrorCode MatRealPart_MPIAIJ(Mat A)
2254 {
2255   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
2256   PetscErrorCode ierr;
2257 
2258   PetscFunctionBegin;
2259   ierr = MatRealPart(a->A);CHKERRQ(ierr);
2260   ierr = MatRealPart(a->B);CHKERRQ(ierr);
2261   PetscFunctionReturn(0);
2262 }
2263 
2264 #undef __FUNCT__
2265 #define __FUNCT__ "MatImaginaryPart_MPIAIJ"
2266 PetscErrorCode MatImaginaryPart_MPIAIJ(Mat A)
2267 {
2268   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
2269   PetscErrorCode ierr;
2270 
2271   PetscFunctionBegin;
2272   ierr = MatImaginaryPart(a->A);CHKERRQ(ierr);
2273   ierr = MatImaginaryPart(a->B);CHKERRQ(ierr);
2274   PetscFunctionReturn(0);
2275 }
2276 
2277 #undef __FUNCT__
2278 #define __FUNCT__ "MatGetRowMaxAbs_MPIAIJ"
2279 PetscErrorCode MatGetRowMaxAbs_MPIAIJ(Mat A, Vec v, PetscInt idx[])
2280 {
2281   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
2282   PetscErrorCode ierr;
2283   PetscInt       i,*idxb = 0;
2284   PetscScalar    *va,*vb;
2285   Vec            vtmp;
2286 
2287   PetscFunctionBegin;
2288   ierr = MatGetRowMaxAbs(a->A,v,idx);CHKERRQ(ierr);
2289   ierr = VecGetArray(v,&va);CHKERRQ(ierr);
2290   if (idx) {
2291     for (i=0; i<A->rmap->n; i++) {
2292       if (PetscAbsScalar(va[i])) idx[i] += A->cmap->rstart;
2293     }
2294   }
2295 
2296   ierr = VecCreateSeq(PETSC_COMM_SELF,A->rmap->n,&vtmp);CHKERRQ(ierr);
2297   if (idx) {
2298     ierr = PetscMalloc1(A->rmap->n,&idxb);CHKERRQ(ierr);
2299   }
2300   ierr = MatGetRowMaxAbs(a->B,vtmp,idxb);CHKERRQ(ierr);
2301   ierr = VecGetArray(vtmp,&vb);CHKERRQ(ierr);
2302 
2303   for (i=0; i<A->rmap->n; i++) {
2304     if (PetscAbsScalar(va[i]) < PetscAbsScalar(vb[i])) {
2305       va[i] = vb[i];
2306       if (idx) idx[i] = a->garray[idxb[i]];
2307     }
2308   }
2309 
2310   ierr = VecRestoreArray(v,&va);CHKERRQ(ierr);
2311   ierr = VecRestoreArray(vtmp,&vb);CHKERRQ(ierr);
2312   ierr = PetscFree(idxb);CHKERRQ(ierr);
2313   ierr = VecDestroy(&vtmp);CHKERRQ(ierr);
2314   PetscFunctionReturn(0);
2315 }
2316 
2317 #undef __FUNCT__
2318 #define __FUNCT__ "MatGetRowMinAbs_MPIAIJ"
2319 PetscErrorCode MatGetRowMinAbs_MPIAIJ(Mat A, Vec v, PetscInt idx[])
2320 {
2321   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
2322   PetscErrorCode ierr;
2323   PetscInt       i,*idxb = 0;
2324   PetscScalar    *va,*vb;
2325   Vec            vtmp;
2326 
2327   PetscFunctionBegin;
2328   ierr = MatGetRowMinAbs(a->A,v,idx);CHKERRQ(ierr);
2329   ierr = VecGetArray(v,&va);CHKERRQ(ierr);
2330   if (idx) {
2331     for (i=0; i<A->cmap->n; i++) {
2332       if (PetscAbsScalar(va[i])) idx[i] += A->cmap->rstart;
2333     }
2334   }
2335 
2336   ierr = VecCreateSeq(PETSC_COMM_SELF,A->rmap->n,&vtmp);CHKERRQ(ierr);
2337   if (idx) {
2338     ierr = PetscMalloc1(A->rmap->n,&idxb);CHKERRQ(ierr);
2339   }
2340   ierr = MatGetRowMinAbs(a->B,vtmp,idxb);CHKERRQ(ierr);
2341   ierr = VecGetArray(vtmp,&vb);CHKERRQ(ierr);
2342 
2343   for (i=0; i<A->rmap->n; i++) {
2344     if (PetscAbsScalar(va[i]) > PetscAbsScalar(vb[i])) {
2345       va[i] = vb[i];
2346       if (idx) idx[i] = a->garray[idxb[i]];
2347     }
2348   }
2349 
2350   ierr = VecRestoreArray(v,&va);CHKERRQ(ierr);
2351   ierr = VecRestoreArray(vtmp,&vb);CHKERRQ(ierr);
2352   ierr = PetscFree(idxb);CHKERRQ(ierr);
2353   ierr = VecDestroy(&vtmp);CHKERRQ(ierr);
2354   PetscFunctionReturn(0);
2355 }
2356 
2357 #undef __FUNCT__
2358 #define __FUNCT__ "MatGetRowMin_MPIAIJ"
2359 PetscErrorCode MatGetRowMin_MPIAIJ(Mat A, Vec v, PetscInt idx[])
2360 {
2361   Mat_MPIAIJ     *mat   = (Mat_MPIAIJ*) A->data;
2362   PetscInt       n      = A->rmap->n;
2363   PetscInt       cstart = A->cmap->rstart;
2364   PetscInt       *cmap  = mat->garray;
2365   PetscInt       *diagIdx, *offdiagIdx;
2366   Vec            diagV, offdiagV;
2367   PetscScalar    *a, *diagA, *offdiagA;
2368   PetscInt       r;
2369   PetscErrorCode ierr;
2370 
2371   PetscFunctionBegin;
2372   ierr = PetscMalloc2(n,&diagIdx,n,&offdiagIdx);CHKERRQ(ierr);
2373   ierr = VecCreateSeq(PetscObjectComm((PetscObject)A), n, &diagV);CHKERRQ(ierr);
2374   ierr = VecCreateSeq(PetscObjectComm((PetscObject)A), n, &offdiagV);CHKERRQ(ierr);
2375   ierr = MatGetRowMin(mat->A, diagV,    diagIdx);CHKERRQ(ierr);
2376   ierr = MatGetRowMin(mat->B, offdiagV, offdiagIdx);CHKERRQ(ierr);
2377   ierr = VecGetArray(v,        &a);CHKERRQ(ierr);
2378   ierr = VecGetArray(diagV,    &diagA);CHKERRQ(ierr);
2379   ierr = VecGetArray(offdiagV, &offdiagA);CHKERRQ(ierr);
2380   for (r = 0; r < n; ++r) {
2381     if (PetscAbsScalar(diagA[r]) <= PetscAbsScalar(offdiagA[r])) {
2382       a[r]   = diagA[r];
2383       idx[r] = cstart + diagIdx[r];
2384     } else {
2385       a[r]   = offdiagA[r];
2386       idx[r] = cmap[offdiagIdx[r]];
2387     }
2388   }
2389   ierr = VecRestoreArray(v,        &a);CHKERRQ(ierr);
2390   ierr = VecRestoreArray(diagV,    &diagA);CHKERRQ(ierr);
2391   ierr = VecRestoreArray(offdiagV, &offdiagA);CHKERRQ(ierr);
2392   ierr = VecDestroy(&diagV);CHKERRQ(ierr);
2393   ierr = VecDestroy(&offdiagV);CHKERRQ(ierr);
2394   ierr = PetscFree2(diagIdx, offdiagIdx);CHKERRQ(ierr);
2395   PetscFunctionReturn(0);
2396 }
2397 
2398 #undef __FUNCT__
2399 #define __FUNCT__ "MatGetRowMax_MPIAIJ"
2400 PetscErrorCode MatGetRowMax_MPIAIJ(Mat A, Vec v, PetscInt idx[])
2401 {
2402   Mat_MPIAIJ     *mat   = (Mat_MPIAIJ*) A->data;
2403   PetscInt       n      = A->rmap->n;
2404   PetscInt       cstart = A->cmap->rstart;
2405   PetscInt       *cmap  = mat->garray;
2406   PetscInt       *diagIdx, *offdiagIdx;
2407   Vec            diagV, offdiagV;
2408   PetscScalar    *a, *diagA, *offdiagA;
2409   PetscInt       r;
2410   PetscErrorCode ierr;
2411 
2412   PetscFunctionBegin;
2413   ierr = PetscMalloc2(n,&diagIdx,n,&offdiagIdx);CHKERRQ(ierr);
2414   ierr = VecCreateSeq(PETSC_COMM_SELF, n, &diagV);CHKERRQ(ierr);
2415   ierr = VecCreateSeq(PETSC_COMM_SELF, n, &offdiagV);CHKERRQ(ierr);
2416   ierr = MatGetRowMax(mat->A, diagV,    diagIdx);CHKERRQ(ierr);
2417   ierr = MatGetRowMax(mat->B, offdiagV, offdiagIdx);CHKERRQ(ierr);
2418   ierr = VecGetArray(v,        &a);CHKERRQ(ierr);
2419   ierr = VecGetArray(diagV,    &diagA);CHKERRQ(ierr);
2420   ierr = VecGetArray(offdiagV, &offdiagA);CHKERRQ(ierr);
2421   for (r = 0; r < n; ++r) {
2422     if (PetscAbsScalar(diagA[r]) >= PetscAbsScalar(offdiagA[r])) {
2423       a[r]   = diagA[r];
2424       idx[r] = cstart + diagIdx[r];
2425     } else {
2426       a[r]   = offdiagA[r];
2427       idx[r] = cmap[offdiagIdx[r]];
2428     }
2429   }
2430   ierr = VecRestoreArray(v,        &a);CHKERRQ(ierr);
2431   ierr = VecRestoreArray(diagV,    &diagA);CHKERRQ(ierr);
2432   ierr = VecRestoreArray(offdiagV, &offdiagA);CHKERRQ(ierr);
2433   ierr = VecDestroy(&diagV);CHKERRQ(ierr);
2434   ierr = VecDestroy(&offdiagV);CHKERRQ(ierr);
2435   ierr = PetscFree2(diagIdx, offdiagIdx);CHKERRQ(ierr);
2436   PetscFunctionReturn(0);
2437 }
2438 
2439 #undef __FUNCT__
2440 #define __FUNCT__ "MatGetSeqNonzeroStructure_MPIAIJ"
2441 PetscErrorCode MatGetSeqNonzeroStructure_MPIAIJ(Mat mat,Mat *newmat)
2442 {
2443   PetscErrorCode ierr;
2444   Mat            *dummy;
2445 
2446   PetscFunctionBegin;
2447   ierr    = MatGetSubMatrix_MPIAIJ_All(mat,MAT_DO_NOT_GET_VALUES,MAT_INITIAL_MATRIX,&dummy);CHKERRQ(ierr);
2448   *newmat = *dummy;
2449   ierr    = PetscFree(dummy);CHKERRQ(ierr);
2450   PetscFunctionReturn(0);
2451 }
2452 
2453 #undef __FUNCT__
2454 #define __FUNCT__ "MatInvertBlockDiagonal_MPIAIJ"
2455 PetscErrorCode  MatInvertBlockDiagonal_MPIAIJ(Mat A,const PetscScalar **values)
2456 {
2457   Mat_MPIAIJ     *a = (Mat_MPIAIJ*) A->data;
2458   PetscErrorCode ierr;
2459 
2460   PetscFunctionBegin;
2461   ierr = MatInvertBlockDiagonal(a->A,values);CHKERRQ(ierr);
2462   PetscFunctionReturn(0);
2463 }
2464 
2465 #undef __FUNCT__
2466 #define __FUNCT__ "MatSetRandom_MPIAIJ"
2467 static PetscErrorCode  MatSetRandom_MPIAIJ(Mat x,PetscRandom rctx)
2468 {
2469   PetscErrorCode ierr;
2470   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)x->data;
2471 
2472   PetscFunctionBegin;
2473   ierr = MatSetRandom(aij->A,rctx);CHKERRQ(ierr);
2474   ierr = MatSetRandom(aij->B,rctx);CHKERRQ(ierr);
2475   ierr = MatAssemblyBegin(x,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
2476   ierr = MatAssemblyEnd(x,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
2477   PetscFunctionReturn(0);
2478 }
2479 
2480 #undef __FUNCT__
2481 #define __FUNCT__ "MatMPIAIJSetUseScalableIncreaseOverlap_MPIAIJ"
2482 PetscErrorCode MatMPIAIJSetUseScalableIncreaseOverlap_MPIAIJ(Mat A,PetscBool sc)
2483 {
2484   PetscFunctionBegin;
2485   if (sc) A->ops->increaseoverlap = MatIncreaseOverlap_MPIAIJ_Scalable;
2486   else A->ops->increaseoverlap    = MatIncreaseOverlap_MPIAIJ;
2487   PetscFunctionReturn(0);
2488 }
2489 
2490 #undef __FUNCT__
2491 #define __FUNCT__ "MatMPIAIJSetUseScalableIncreaseOverlap"
2492 /*@
2493    MatMPIAIJSetUseScalableIncreaseOverlap - Determine if the matrix uses a scalable algorithm to compute the overlap
2494 
2495    Collective on Mat
2496 
2497    Input Parameters:
2498 +    A - the matrix
2499 -    sc - PETSC_TRUE indicates use the scalable algorithm (default is not to use the scalable algorithm)
2500 
2501 @*/
2502 PetscErrorCode MatMPIAIJSetUseScalableIncreaseOverlap(Mat A,PetscBool sc)
2503 {
2504   PetscErrorCode       ierr;
2505 
2506   PetscFunctionBegin;
2507   ierr = PetscTryMethod(A,"MatMPIAIJSetUseScalableIncreaseOverlap_C",(Mat,PetscBool),(A,sc));CHKERRQ(ierr);
2508   PetscFunctionReturn(0);
2509 }
2510 
2511 #undef __FUNCT__
2512 #define __FUNCT__ "MatSetFromOptions_MPIAIJ"
2513 PetscErrorCode MatSetFromOptions_MPIAIJ(PetscOptions *PetscOptionsObject,Mat A)
2514 {
2515   PetscErrorCode       ierr;
2516   PetscBool            sc = PETSC_FALSE,flg;
2517 
2518   PetscFunctionBegin;
2519   ierr = PetscOptionsHead(PetscOptionsObject,"MPIAIJ options");CHKERRQ(ierr);
2520   ierr = PetscObjectOptionsBegin((PetscObject)A);
2521     if (A->ops->increaseoverlap == MatIncreaseOverlap_MPIAIJ_Scalable) sc = PETSC_TRUE;
2522     ierr = PetscOptionsBool("-mat_increase_overlap_scalable","Use a scalable algorithm to compute the overlap","MatIncreaseOverlap",sc,&sc,&flg);CHKERRQ(ierr);
2523     if (flg) {
2524       ierr = MatMPIAIJSetUseScalableIncreaseOverlap(A,sc);CHKERRQ(ierr);
2525     }
2526   ierr = PetscOptionsEnd();CHKERRQ(ierr);
2527   PetscFunctionReturn(0);
2528 }
2529 
2530 #undef __FUNCT__
2531 #define __FUNCT__ "MatShift_MPIAIJ"
2532 PetscErrorCode MatShift_MPIAIJ(Mat Y,PetscScalar a)
2533 {
2534   PetscErrorCode ierr;
2535   Mat_MPIAIJ     *maij = (Mat_MPIAIJ*)Y->data;
2536   Mat_SeqAIJ     *aij = (Mat_SeqAIJ*)maij->A->data;
2537 
2538   PetscFunctionBegin;
2539   if (!Y->preallocated) {
2540     ierr = MatMPIAIJSetPreallocation(Y,1,NULL,0,NULL);CHKERRQ(ierr);
2541   } else if (!aij->nz) {
2542     PetscInt nonew = aij->nonew;
2543     ierr = MatSeqAIJSetPreallocation(maij->A,1,NULL);CHKERRQ(ierr);
2544     aij->nonew = nonew;
2545   }
2546   ierr = MatShift_Basic(Y,a);CHKERRQ(ierr);
2547   PetscFunctionReturn(0);
2548 }
2549 
2550 /* -------------------------------------------------------------------*/
2551 static struct _MatOps MatOps_Values = {MatSetValues_MPIAIJ,
2552                                        MatGetRow_MPIAIJ,
2553                                        MatRestoreRow_MPIAIJ,
2554                                        MatMult_MPIAIJ,
2555                                 /* 4*/ MatMultAdd_MPIAIJ,
2556                                        MatMultTranspose_MPIAIJ,
2557                                        MatMultTransposeAdd_MPIAIJ,
2558                                        0,
2559                                        0,
2560                                        0,
2561                                 /*10*/ 0,
2562                                        0,
2563                                        0,
2564                                        MatSOR_MPIAIJ,
2565                                        MatTranspose_MPIAIJ,
2566                                 /*15*/ MatGetInfo_MPIAIJ,
2567                                        MatEqual_MPIAIJ,
2568                                        MatGetDiagonal_MPIAIJ,
2569                                        MatDiagonalScale_MPIAIJ,
2570                                        MatNorm_MPIAIJ,
2571                                 /*20*/ MatAssemblyBegin_MPIAIJ,
2572                                        MatAssemblyEnd_MPIAIJ,
2573                                        MatSetOption_MPIAIJ,
2574                                        MatZeroEntries_MPIAIJ,
2575                                 /*24*/ MatZeroRows_MPIAIJ,
2576                                        0,
2577                                        0,
2578                                        0,
2579                                        0,
2580                                 /*29*/ MatSetUp_MPIAIJ,
2581                                        0,
2582                                        0,
2583                                        0,
2584                                        0,
2585                                 /*34*/ MatDuplicate_MPIAIJ,
2586                                        0,
2587                                        0,
2588                                        0,
2589                                        0,
2590                                 /*39*/ MatAXPY_MPIAIJ,
2591                                        MatGetSubMatrices_MPIAIJ,
2592                                        MatIncreaseOverlap_MPIAIJ,
2593                                        MatGetValues_MPIAIJ,
2594                                        MatCopy_MPIAIJ,
2595                                 /*44*/ MatGetRowMax_MPIAIJ,
2596                                        MatScale_MPIAIJ,
2597                                        MatShift_MPIAIJ,
2598                                        MatDiagonalSet_MPIAIJ,
2599                                        MatZeroRowsColumns_MPIAIJ,
2600                                 /*49*/ MatSetRandom_MPIAIJ,
2601                                        0,
2602                                        0,
2603                                        0,
2604                                        0,
2605                                 /*54*/ MatFDColoringCreate_MPIXAIJ,
2606                                        0,
2607                                        MatSetUnfactored_MPIAIJ,
2608                                        MatPermute_MPIAIJ,
2609                                        0,
2610                                 /*59*/ MatGetSubMatrix_MPIAIJ,
2611                                        MatDestroy_MPIAIJ,
2612                                        MatView_MPIAIJ,
2613                                        0,
2614                                        MatMatMatMult_MPIAIJ_MPIAIJ_MPIAIJ,
2615                                 /*64*/ MatMatMatMultSymbolic_MPIAIJ_MPIAIJ_MPIAIJ,
2616                                        MatMatMatMultNumeric_MPIAIJ_MPIAIJ_MPIAIJ,
2617                                        0,
2618                                        0,
2619                                        0,
2620                                 /*69*/ MatGetRowMaxAbs_MPIAIJ,
2621                                        MatGetRowMinAbs_MPIAIJ,
2622                                        0,
2623                                        MatSetColoring_MPIAIJ,
2624                                        0,
2625                                        MatSetValuesAdifor_MPIAIJ,
2626                                 /*75*/ MatFDColoringApply_AIJ,
2627                                        MatSetFromOptions_MPIAIJ,
2628                                        0,
2629                                        0,
2630                                        MatFindZeroDiagonals_MPIAIJ,
2631                                 /*80*/ 0,
2632                                        0,
2633                                        0,
2634                                 /*83*/ MatLoad_MPIAIJ,
2635                                        0,
2636                                        0,
2637                                        0,
2638                                        0,
2639                                        0,
2640                                 /*89*/ MatMatMult_MPIAIJ_MPIAIJ,
2641                                        MatMatMultSymbolic_MPIAIJ_MPIAIJ,
2642                                        MatMatMultNumeric_MPIAIJ_MPIAIJ,
2643                                        MatPtAP_MPIAIJ_MPIAIJ,
2644                                        MatPtAPSymbolic_MPIAIJ_MPIAIJ,
2645                                 /*94*/ MatPtAPNumeric_MPIAIJ_MPIAIJ,
2646                                        0,
2647                                        0,
2648                                        0,
2649                                        0,
2650                                 /*99*/ 0,
2651                                        0,
2652                                        0,
2653                                        MatConjugate_MPIAIJ,
2654                                        0,
2655                                 /*104*/MatSetValuesRow_MPIAIJ,
2656                                        MatRealPart_MPIAIJ,
2657                                        MatImaginaryPart_MPIAIJ,
2658                                        0,
2659                                        0,
2660                                 /*109*/0,
2661                                        0,
2662                                        MatGetRowMin_MPIAIJ,
2663                                        0,
2664                                        0,
2665                                 /*114*/MatGetSeqNonzeroStructure_MPIAIJ,
2666                                        0,
2667                                        MatGetGhosts_MPIAIJ,
2668                                        0,
2669                                        0,
2670                                 /*119*/0,
2671                                        0,
2672                                        0,
2673                                        0,
2674                                        MatGetMultiProcBlock_MPIAIJ,
2675                                 /*124*/MatFindNonzeroRows_MPIAIJ,
2676                                        MatGetColumnNorms_MPIAIJ,
2677                                        MatInvertBlockDiagonal_MPIAIJ,
2678                                        0,
2679                                        MatGetSubMatricesMPI_MPIAIJ,
2680                                 /*129*/0,
2681                                        MatTransposeMatMult_MPIAIJ_MPIAIJ,
2682                                        MatTransposeMatMultSymbolic_MPIAIJ_MPIAIJ,
2683                                        MatTransposeMatMultNumeric_MPIAIJ_MPIAIJ,
2684                                        0,
2685                                 /*134*/0,
2686                                        0,
2687                                        0,
2688                                        0,
2689                                        0,
2690                                 /*139*/0,
2691                                        0,
2692                                        0,
2693                                        MatFDColoringSetUp_MPIXAIJ,
2694                                        MatFindOffBlockDiagonalEntries_MPIAIJ,
2695                                 /*144*/MatCreateMPIMatConcatenateSeqMat_MPIAIJ
2696 };
2697 
2698 /* ----------------------------------------------------------------------------------------*/
2699 
2700 #undef __FUNCT__
2701 #define __FUNCT__ "MatStoreValues_MPIAIJ"
2702 PetscErrorCode  MatStoreValues_MPIAIJ(Mat mat)
2703 {
2704   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
2705   PetscErrorCode ierr;
2706 
2707   PetscFunctionBegin;
2708   ierr = MatStoreValues(aij->A);CHKERRQ(ierr);
2709   ierr = MatStoreValues(aij->B);CHKERRQ(ierr);
2710   PetscFunctionReturn(0);
2711 }
2712 
2713 #undef __FUNCT__
2714 #define __FUNCT__ "MatRetrieveValues_MPIAIJ"
2715 PetscErrorCode  MatRetrieveValues_MPIAIJ(Mat mat)
2716 {
2717   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
2718   PetscErrorCode ierr;
2719 
2720   PetscFunctionBegin;
2721   ierr = MatRetrieveValues(aij->A);CHKERRQ(ierr);
2722   ierr = MatRetrieveValues(aij->B);CHKERRQ(ierr);
2723   PetscFunctionReturn(0);
2724 }
2725 
2726 #undef __FUNCT__
2727 #define __FUNCT__ "MatMPIAIJSetPreallocation_MPIAIJ"
2728 PetscErrorCode  MatMPIAIJSetPreallocation_MPIAIJ(Mat B,PetscInt d_nz,const PetscInt d_nnz[],PetscInt o_nz,const PetscInt o_nnz[])
2729 {
2730   Mat_MPIAIJ     *b;
2731   PetscErrorCode ierr;
2732 
2733   PetscFunctionBegin;
2734   ierr = PetscLayoutSetUp(B->rmap);CHKERRQ(ierr);
2735   ierr = PetscLayoutSetUp(B->cmap);CHKERRQ(ierr);
2736   b = (Mat_MPIAIJ*)B->data;
2737 
2738   if (!B->preallocated) {
2739     /* Explicitly create 2 MATSEQAIJ matrices. */
2740     ierr = MatCreate(PETSC_COMM_SELF,&b->A);CHKERRQ(ierr);
2741     ierr = MatSetSizes(b->A,B->rmap->n,B->cmap->n,B->rmap->n,B->cmap->n);CHKERRQ(ierr);
2742     ierr = MatSetBlockSizesFromMats(b->A,B,B);CHKERRQ(ierr);
2743     ierr = MatSetType(b->A,MATSEQAIJ);CHKERRQ(ierr);
2744     ierr = PetscLogObjectParent((PetscObject)B,(PetscObject)b->A);CHKERRQ(ierr);
2745     ierr = MatCreate(PETSC_COMM_SELF,&b->B);CHKERRQ(ierr);
2746     ierr = MatSetSizes(b->B,B->rmap->n,B->cmap->N,B->rmap->n,B->cmap->N);CHKERRQ(ierr);
2747     ierr = MatSetBlockSizesFromMats(b->B,B,B);CHKERRQ(ierr);
2748     ierr = MatSetType(b->B,MATSEQAIJ);CHKERRQ(ierr);
2749     ierr = PetscLogObjectParent((PetscObject)B,(PetscObject)b->B);CHKERRQ(ierr);
2750   }
2751 
2752   ierr = MatSeqAIJSetPreallocation(b->A,d_nz,d_nnz);CHKERRQ(ierr);
2753   ierr = MatSeqAIJSetPreallocation(b->B,o_nz,o_nnz);CHKERRQ(ierr);
2754   B->preallocated = PETSC_TRUE;
2755   PetscFunctionReturn(0);
2756 }
2757 
2758 #undef __FUNCT__
2759 #define __FUNCT__ "MatDuplicate_MPIAIJ"
2760 PetscErrorCode MatDuplicate_MPIAIJ(Mat matin,MatDuplicateOption cpvalues,Mat *newmat)
2761 {
2762   Mat            mat;
2763   Mat_MPIAIJ     *a,*oldmat = (Mat_MPIAIJ*)matin->data;
2764   PetscErrorCode ierr;
2765 
2766   PetscFunctionBegin;
2767   *newmat = 0;
2768   ierr    = MatCreate(PetscObjectComm((PetscObject)matin),&mat);CHKERRQ(ierr);
2769   ierr    = MatSetSizes(mat,matin->rmap->n,matin->cmap->n,matin->rmap->N,matin->cmap->N);CHKERRQ(ierr);
2770   ierr    = MatSetBlockSizesFromMats(mat,matin,matin);CHKERRQ(ierr);
2771   ierr    = MatSetType(mat,((PetscObject)matin)->type_name);CHKERRQ(ierr);
2772   ierr    = PetscMemcpy(mat->ops,matin->ops,sizeof(struct _MatOps));CHKERRQ(ierr);
2773   a       = (Mat_MPIAIJ*)mat->data;
2774 
2775   mat->factortype   = matin->factortype;
2776   mat->assembled    = PETSC_TRUE;
2777   mat->insertmode   = NOT_SET_VALUES;
2778   mat->preallocated = PETSC_TRUE;
2779 
2780   a->size         = oldmat->size;
2781   a->rank         = oldmat->rank;
2782   a->donotstash   = oldmat->donotstash;
2783   a->roworiented  = oldmat->roworiented;
2784   a->rowindices   = 0;
2785   a->rowvalues    = 0;
2786   a->getrowactive = PETSC_FALSE;
2787 
2788   ierr = PetscLayoutReference(matin->rmap,&mat->rmap);CHKERRQ(ierr);
2789   ierr = PetscLayoutReference(matin->cmap,&mat->cmap);CHKERRQ(ierr);
2790 
2791   if (oldmat->colmap) {
2792 #if defined(PETSC_USE_CTABLE)
2793     ierr = PetscTableCreateCopy(oldmat->colmap,&a->colmap);CHKERRQ(ierr);
2794 #else
2795     ierr = PetscMalloc1(mat->cmap->N,&a->colmap);CHKERRQ(ierr);
2796     ierr = PetscLogObjectMemory((PetscObject)mat,(mat->cmap->N)*sizeof(PetscInt));CHKERRQ(ierr);
2797     ierr = PetscMemcpy(a->colmap,oldmat->colmap,(mat->cmap->N)*sizeof(PetscInt));CHKERRQ(ierr);
2798 #endif
2799   } else a->colmap = 0;
2800   if (oldmat->garray) {
2801     PetscInt len;
2802     len  = oldmat->B->cmap->n;
2803     ierr = PetscMalloc1(len+1,&a->garray);CHKERRQ(ierr);
2804     ierr = PetscLogObjectMemory((PetscObject)mat,len*sizeof(PetscInt));CHKERRQ(ierr);
2805     if (len) { ierr = PetscMemcpy(a->garray,oldmat->garray,len*sizeof(PetscInt));CHKERRQ(ierr); }
2806   } else a->garray = 0;
2807 
2808   ierr    = VecDuplicate(oldmat->lvec,&a->lvec);CHKERRQ(ierr);
2809   ierr    = PetscLogObjectParent((PetscObject)mat,(PetscObject)a->lvec);CHKERRQ(ierr);
2810   ierr    = VecScatterCopy(oldmat->Mvctx,&a->Mvctx);CHKERRQ(ierr);
2811   ierr    = PetscLogObjectParent((PetscObject)mat,(PetscObject)a->Mvctx);CHKERRQ(ierr);
2812   ierr    = MatDuplicate(oldmat->A,cpvalues,&a->A);CHKERRQ(ierr);
2813   ierr    = PetscLogObjectParent((PetscObject)mat,(PetscObject)a->A);CHKERRQ(ierr);
2814   ierr    = MatDuplicate(oldmat->B,cpvalues,&a->B);CHKERRQ(ierr);
2815   ierr    = PetscLogObjectParent((PetscObject)mat,(PetscObject)a->B);CHKERRQ(ierr);
2816   ierr    = PetscFunctionListDuplicate(((PetscObject)matin)->qlist,&((PetscObject)mat)->qlist);CHKERRQ(ierr);
2817   *newmat = mat;
2818   PetscFunctionReturn(0);
2819 }
2820 
2821 
2822 
2823 #undef __FUNCT__
2824 #define __FUNCT__ "MatLoad_MPIAIJ"
2825 PetscErrorCode MatLoad_MPIAIJ(Mat newMat, PetscViewer viewer)
2826 {
2827   PetscScalar    *vals,*svals;
2828   MPI_Comm       comm;
2829   PetscErrorCode ierr;
2830   PetscMPIInt    rank,size,tag = ((PetscObject)viewer)->tag;
2831   PetscInt       i,nz,j,rstart,rend,mmax,maxnz = 0;
2832   PetscInt       header[4],*rowlengths = 0,M,N,m,*cols;
2833   PetscInt       *ourlens = NULL,*procsnz = NULL,*offlens = NULL,jj,*mycols,*smycols;
2834   PetscInt       cend,cstart,n,*rowners;
2835   int            fd;
2836   PetscInt       bs = newMat->rmap->bs;
2837 
2838   PetscFunctionBegin;
2839   /* force binary viewer to load .info file if it has not yet done so */
2840   ierr = PetscViewerSetUp(viewer);CHKERRQ(ierr);
2841   ierr = PetscObjectGetComm((PetscObject)viewer,&comm);CHKERRQ(ierr);
2842   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
2843   ierr = MPI_Comm_rank(comm,&rank);CHKERRQ(ierr);
2844   ierr = PetscViewerBinaryGetDescriptor(viewer,&fd);CHKERRQ(ierr);
2845   if (!rank) {
2846     ierr = PetscBinaryRead(fd,(char*)header,4,PETSC_INT);CHKERRQ(ierr);
2847     if (header[0] != MAT_FILE_CLASSID) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_FILE_UNEXPECTED,"not matrix object");
2848   }
2849 
2850   ierr = PetscOptionsBegin(comm,NULL,"Options for loading MPIAIJ matrix","Mat");CHKERRQ(ierr);
2851   ierr = PetscOptionsInt("-matload_block_size","Set the blocksize used to store the matrix","MatLoad",bs,&bs,NULL);CHKERRQ(ierr);
2852   ierr = PetscOptionsEnd();CHKERRQ(ierr);
2853   if (bs < 0) bs = 1;
2854 
2855   ierr = MPI_Bcast(header+1,3,MPIU_INT,0,comm);CHKERRQ(ierr);
2856   M    = header[1]; N = header[2];
2857 
2858   /* If global sizes are set, check if they are consistent with that given in the file */
2859   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);
2860   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);
2861 
2862   /* determine ownership of all (block) rows */
2863   if (M%bs) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_FILE_UNEXPECTED, "Inconsistent # of rows (%d) and block size (%d)",M,bs);
2864   if (newMat->rmap->n < 0) m = bs*((M/bs)/size + (((M/bs) % size) > rank));    /* PETSC_DECIDE */
2865   else m = newMat->rmap->n; /* Set by user */
2866 
2867   ierr = PetscMalloc1(size+1,&rowners);CHKERRQ(ierr);
2868   ierr = MPI_Allgather(&m,1,MPIU_INT,rowners+1,1,MPIU_INT,comm);CHKERRQ(ierr);
2869 
2870   /* First process needs enough room for process with most rows */
2871   if (!rank) {
2872     mmax = rowners[1];
2873     for (i=2; i<=size; i++) {
2874       mmax = PetscMax(mmax, rowners[i]);
2875     }
2876   } else mmax = -1;             /* unused, but compilers complain */
2877 
2878   rowners[0] = 0;
2879   for (i=2; i<=size; i++) {
2880     rowners[i] += rowners[i-1];
2881   }
2882   rstart = rowners[rank];
2883   rend   = rowners[rank+1];
2884 
2885   /* distribute row lengths to all processors */
2886   ierr = PetscMalloc2(m,&ourlens,m,&offlens);CHKERRQ(ierr);
2887   if (!rank) {
2888     ierr = PetscBinaryRead(fd,ourlens,m,PETSC_INT);CHKERRQ(ierr);
2889     ierr = PetscMalloc1(mmax,&rowlengths);CHKERRQ(ierr);
2890     ierr = PetscCalloc1(size,&procsnz);CHKERRQ(ierr);
2891     for (j=0; j<m; j++) {
2892       procsnz[0] += ourlens[j];
2893     }
2894     for (i=1; i<size; i++) {
2895       ierr = PetscBinaryRead(fd,rowlengths,rowners[i+1]-rowners[i],PETSC_INT);CHKERRQ(ierr);
2896       /* calculate the number of nonzeros on each processor */
2897       for (j=0; j<rowners[i+1]-rowners[i]; j++) {
2898         procsnz[i] += rowlengths[j];
2899       }
2900       ierr = MPIULong_Send(rowlengths,rowners[i+1]-rowners[i],MPIU_INT,i,tag,comm);CHKERRQ(ierr);
2901     }
2902     ierr = PetscFree(rowlengths);CHKERRQ(ierr);
2903   } else {
2904     ierr = MPIULong_Recv(ourlens,m,MPIU_INT,0,tag,comm);CHKERRQ(ierr);
2905   }
2906 
2907   if (!rank) {
2908     /* determine max buffer needed and allocate it */
2909     maxnz = 0;
2910     for (i=0; i<size; i++) {
2911       maxnz = PetscMax(maxnz,procsnz[i]);
2912     }
2913     ierr = PetscMalloc1(maxnz,&cols);CHKERRQ(ierr);
2914 
2915     /* read in my part of the matrix column indices  */
2916     nz   = procsnz[0];
2917     ierr = PetscMalloc1(nz,&mycols);CHKERRQ(ierr);
2918     ierr = PetscBinaryRead(fd,mycols,nz,PETSC_INT);CHKERRQ(ierr);
2919 
2920     /* read in every one elses and ship off */
2921     for (i=1; i<size; i++) {
2922       nz   = procsnz[i];
2923       ierr = PetscBinaryRead(fd,cols,nz,PETSC_INT);CHKERRQ(ierr);
2924       ierr = MPIULong_Send(cols,nz,MPIU_INT,i,tag,comm);CHKERRQ(ierr);
2925     }
2926     ierr = PetscFree(cols);CHKERRQ(ierr);
2927   } else {
2928     /* determine buffer space needed for message */
2929     nz = 0;
2930     for (i=0; i<m; i++) {
2931       nz += ourlens[i];
2932     }
2933     ierr = PetscMalloc1(nz,&mycols);CHKERRQ(ierr);
2934 
2935     /* receive message of column indices*/
2936     ierr = MPIULong_Recv(mycols,nz,MPIU_INT,0,tag,comm);CHKERRQ(ierr);
2937   }
2938 
2939   /* determine column ownership if matrix is not square */
2940   if (N != M) {
2941     if (newMat->cmap->n < 0) n = N/size + ((N % size) > rank);
2942     else n = newMat->cmap->n;
2943     ierr   = MPI_Scan(&n,&cend,1,MPIU_INT,MPI_SUM,comm);CHKERRQ(ierr);
2944     cstart = cend - n;
2945   } else {
2946     cstart = rstart;
2947     cend   = rend;
2948     n      = cend - cstart;
2949   }
2950 
2951   /* loop over local rows, determining number of off diagonal entries */
2952   ierr = PetscMemzero(offlens,m*sizeof(PetscInt));CHKERRQ(ierr);
2953   jj   = 0;
2954   for (i=0; i<m; i++) {
2955     for (j=0; j<ourlens[i]; j++) {
2956       if (mycols[jj] < cstart || mycols[jj] >= cend) offlens[i]++;
2957       jj++;
2958     }
2959   }
2960 
2961   for (i=0; i<m; i++) {
2962     ourlens[i] -= offlens[i];
2963   }
2964   ierr = MatSetSizes(newMat,m,n,M,N);CHKERRQ(ierr);
2965 
2966   if (bs > 1) {ierr = MatSetBlockSize(newMat,bs);CHKERRQ(ierr);}
2967 
2968   ierr = MatMPIAIJSetPreallocation(newMat,0,ourlens,0,offlens);CHKERRQ(ierr);
2969 
2970   for (i=0; i<m; i++) {
2971     ourlens[i] += offlens[i];
2972   }
2973 
2974   if (!rank) {
2975     ierr = PetscMalloc1(maxnz+1,&vals);CHKERRQ(ierr);
2976 
2977     /* read in my part of the matrix numerical values  */
2978     nz   = procsnz[0];
2979     ierr = PetscBinaryRead(fd,vals,nz,PETSC_SCALAR);CHKERRQ(ierr);
2980 
2981     /* insert into matrix */
2982     jj      = rstart;
2983     smycols = mycols;
2984     svals   = vals;
2985     for (i=0; i<m; i++) {
2986       ierr     = MatSetValues_MPIAIJ(newMat,1,&jj,ourlens[i],smycols,svals,INSERT_VALUES);CHKERRQ(ierr);
2987       smycols += ourlens[i];
2988       svals   += ourlens[i];
2989       jj++;
2990     }
2991 
2992     /* read in other processors and ship out */
2993     for (i=1; i<size; i++) {
2994       nz   = procsnz[i];
2995       ierr = PetscBinaryRead(fd,vals,nz,PETSC_SCALAR);CHKERRQ(ierr);
2996       ierr = MPIULong_Send(vals,nz,MPIU_SCALAR,i,((PetscObject)newMat)->tag,comm);CHKERRQ(ierr);
2997     }
2998     ierr = PetscFree(procsnz);CHKERRQ(ierr);
2999   } else {
3000     /* receive numeric values */
3001     ierr = PetscMalloc1(nz+1,&vals);CHKERRQ(ierr);
3002 
3003     /* receive message of values*/
3004     ierr = MPIULong_Recv(vals,nz,MPIU_SCALAR,0,((PetscObject)newMat)->tag,comm);CHKERRQ(ierr);
3005 
3006     /* insert into matrix */
3007     jj      = rstart;
3008     smycols = mycols;
3009     svals   = vals;
3010     for (i=0; i<m; i++) {
3011       ierr     = MatSetValues_MPIAIJ(newMat,1,&jj,ourlens[i],smycols,svals,INSERT_VALUES);CHKERRQ(ierr);
3012       smycols += ourlens[i];
3013       svals   += ourlens[i];
3014       jj++;
3015     }
3016   }
3017   ierr = PetscFree2(ourlens,offlens);CHKERRQ(ierr);
3018   ierr = PetscFree(vals);CHKERRQ(ierr);
3019   ierr = PetscFree(mycols);CHKERRQ(ierr);
3020   ierr = PetscFree(rowners);CHKERRQ(ierr);
3021   ierr = MatAssemblyBegin(newMat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
3022   ierr = MatAssemblyEnd(newMat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
3023   PetscFunctionReturn(0);
3024 }
3025 
3026 #undef __FUNCT__
3027 #define __FUNCT__ "MatGetSubMatrix_MPIAIJ"
3028 /* TODO: Not scalable because of ISAllGather() unless getting all columns. */
3029 PetscErrorCode MatGetSubMatrix_MPIAIJ(Mat mat,IS isrow,IS iscol,MatReuse call,Mat *newmat)
3030 {
3031   PetscErrorCode ierr;
3032   IS             iscol_local;
3033   PetscInt       csize;
3034 
3035   PetscFunctionBegin;
3036   ierr = ISGetLocalSize(iscol,&csize);CHKERRQ(ierr);
3037   if (call == MAT_REUSE_MATRIX) {
3038     ierr = PetscObjectQuery((PetscObject)*newmat,"ISAllGather",(PetscObject*)&iscol_local);CHKERRQ(ierr);
3039     if (!iscol_local) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"Submatrix passed in was not used before, cannot reuse");
3040   } else {
3041     /* check if we are grabbing all columns*/
3042     PetscBool    isstride;
3043     PetscMPIInt  lisstride = 0,gisstride;
3044     ierr = PetscObjectTypeCompare((PetscObject)iscol,ISSTRIDE,&isstride);CHKERRQ(ierr);
3045     if (isstride) {
3046       PetscInt  start,len,mstart,mlen;
3047       ierr = ISStrideGetInfo(iscol,&start,NULL);CHKERRQ(ierr);
3048       ierr = ISGetLocalSize(iscol,&len);CHKERRQ(ierr);
3049       ierr = MatGetOwnershipRangeColumn(mat,&mstart,&mlen);CHKERRQ(ierr);
3050       if (mstart == start && mlen-mstart == len) lisstride = 1;
3051     }
3052     ierr = MPIU_Allreduce(&lisstride,&gisstride,1,MPI_INT,MPI_MIN,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
3053     if (gisstride) {
3054       PetscInt N;
3055       ierr = MatGetSize(mat,NULL,&N);CHKERRQ(ierr);
3056       ierr = ISCreateStride(PetscObjectComm((PetscObject)mat),N,0,1,&iscol_local);CHKERRQ(ierr);
3057       ierr = ISSetIdentity(iscol_local);CHKERRQ(ierr);
3058       ierr = PetscInfo(mat,"Optimizing for obtaining all columns of the matrix; skipping ISAllGather()\n");CHKERRQ(ierr);
3059     } else {
3060       PetscInt cbs;
3061       ierr = ISGetBlockSize(iscol,&cbs);CHKERRQ(ierr);
3062       ierr = ISAllGather(iscol,&iscol_local);CHKERRQ(ierr);
3063       ierr = ISSetBlockSize(iscol_local,cbs);CHKERRQ(ierr);
3064     }
3065   }
3066   ierr = MatGetSubMatrix_MPIAIJ_Private(mat,isrow,iscol_local,csize,call,newmat);CHKERRQ(ierr);
3067   if (call == MAT_INITIAL_MATRIX) {
3068     ierr = PetscObjectCompose((PetscObject)*newmat,"ISAllGather",(PetscObject)iscol_local);CHKERRQ(ierr);
3069     ierr = ISDestroy(&iscol_local);CHKERRQ(ierr);
3070   }
3071   PetscFunctionReturn(0);
3072 }
3073 
3074 extern PetscErrorCode MatGetSubMatrices_MPIAIJ_Local(Mat,PetscInt,const IS[],const IS[],MatReuse,PetscBool*,Mat*);
3075 #undef __FUNCT__
3076 #define __FUNCT__ "MatGetSubMatrix_MPIAIJ_Private"
3077 /*
3078     Not great since it makes two copies of the submatrix, first an SeqAIJ
3079   in local and then by concatenating the local matrices the end result.
3080   Writing it directly would be much like MatGetSubMatrices_MPIAIJ()
3081 
3082   Note: This requires a sequential iscol with all indices.
3083 */
3084 PetscErrorCode MatGetSubMatrix_MPIAIJ_Private(Mat mat,IS isrow,IS iscol,PetscInt csize,MatReuse call,Mat *newmat)
3085 {
3086   PetscErrorCode ierr;
3087   PetscMPIInt    rank,size;
3088   PetscInt       i,m,n,rstart,row,rend,nz,*cwork,j,bs,cbs;
3089   PetscInt       *ii,*jj,nlocal,*dlens,*olens,dlen,olen,jend,mglobal,ncol;
3090   PetscBool      allcolumns, colflag;
3091   Mat            M,Mreuse;
3092   MatScalar      *vwork,*aa;
3093   MPI_Comm       comm;
3094   Mat_SeqAIJ     *aij;
3095 
3096   PetscFunctionBegin;
3097   ierr = PetscObjectGetComm((PetscObject)mat,&comm);CHKERRQ(ierr);
3098   ierr = MPI_Comm_rank(comm,&rank);CHKERRQ(ierr);
3099   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
3100 
3101   ierr = ISIdentity(iscol,&colflag);CHKERRQ(ierr);
3102   ierr = ISGetLocalSize(iscol,&ncol);CHKERRQ(ierr);
3103   if (colflag && ncol == mat->cmap->N) {
3104     allcolumns = PETSC_TRUE;
3105     ierr = PetscInfo(mat,"Optimizing for obtaining all columns of the matrix\n");CHKERRQ(ierr);
3106   } else {
3107     allcolumns = PETSC_FALSE;
3108   }
3109   if (call ==  MAT_REUSE_MATRIX) {
3110     ierr = PetscObjectQuery((PetscObject)*newmat,"SubMatrix",(PetscObject*)&Mreuse);CHKERRQ(ierr);
3111     if (!Mreuse) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"Submatrix passed in was not used before, cannot reuse");
3112     ierr = MatGetSubMatrices_MPIAIJ_Local(mat,1,&isrow,&iscol,MAT_REUSE_MATRIX,&allcolumns,&Mreuse);CHKERRQ(ierr);
3113   } else {
3114     ierr = MatGetSubMatrices_MPIAIJ_Local(mat,1,&isrow,&iscol,MAT_INITIAL_MATRIX,&allcolumns,&Mreuse);CHKERRQ(ierr);
3115   }
3116 
3117   /*
3118       m - number of local rows
3119       n - number of columns (same on all processors)
3120       rstart - first row in new global matrix generated
3121   */
3122   ierr = MatGetSize(Mreuse,&m,&n);CHKERRQ(ierr);
3123   ierr = MatGetBlockSizes(Mreuse,&bs,&cbs);CHKERRQ(ierr);
3124   if (call == MAT_INITIAL_MATRIX) {
3125     aij = (Mat_SeqAIJ*)(Mreuse)->data;
3126     ii  = aij->i;
3127     jj  = aij->j;
3128 
3129     /*
3130         Determine the number of non-zeros in the diagonal and off-diagonal
3131         portions of the matrix in order to do correct preallocation
3132     */
3133 
3134     /* first get start and end of "diagonal" columns */
3135     if (csize == PETSC_DECIDE) {
3136       ierr = ISGetSize(isrow,&mglobal);CHKERRQ(ierr);
3137       if (mglobal == n) { /* square matrix */
3138         nlocal = m;
3139       } else {
3140         nlocal = n/size + ((n % size) > rank);
3141       }
3142     } else {
3143       nlocal = csize;
3144     }
3145     ierr   = MPI_Scan(&nlocal,&rend,1,MPIU_INT,MPI_SUM,comm);CHKERRQ(ierr);
3146     rstart = rend - nlocal;
3147     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);
3148 
3149     /* next, compute all the lengths */
3150     ierr  = PetscMalloc1(2*m+1,&dlens);CHKERRQ(ierr);
3151     olens = dlens + m;
3152     for (i=0; i<m; i++) {
3153       jend = ii[i+1] - ii[i];
3154       olen = 0;
3155       dlen = 0;
3156       for (j=0; j<jend; j++) {
3157         if (*jj < rstart || *jj >= rend) olen++;
3158         else dlen++;
3159         jj++;
3160       }
3161       olens[i] = olen;
3162       dlens[i] = dlen;
3163     }
3164     ierr = MatCreate(comm,&M);CHKERRQ(ierr);
3165     ierr = MatSetSizes(M,m,nlocal,PETSC_DECIDE,n);CHKERRQ(ierr);
3166     ierr = MatSetBlockSizes(M,bs,cbs);CHKERRQ(ierr);
3167     ierr = MatSetType(M,((PetscObject)mat)->type_name);CHKERRQ(ierr);
3168     ierr = MatMPIAIJSetPreallocation(M,0,dlens,0,olens);CHKERRQ(ierr);
3169     ierr = PetscFree(dlens);CHKERRQ(ierr);
3170   } else {
3171     PetscInt ml,nl;
3172 
3173     M    = *newmat;
3174     ierr = MatGetLocalSize(M,&ml,&nl);CHKERRQ(ierr);
3175     if (ml != m) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_SIZ,"Previous matrix must be same size/layout as request");
3176     ierr = MatZeroEntries(M);CHKERRQ(ierr);
3177     /*
3178          The next two lines are needed so we may call MatSetValues_MPIAIJ() below directly,
3179        rather than the slower MatSetValues().
3180     */
3181     M->was_assembled = PETSC_TRUE;
3182     M->assembled     = PETSC_FALSE;
3183   }
3184   ierr = MatGetOwnershipRange(M,&rstart,&rend);CHKERRQ(ierr);
3185   aij  = (Mat_SeqAIJ*)(Mreuse)->data;
3186   ii   = aij->i;
3187   jj   = aij->j;
3188   aa   = aij->a;
3189   for (i=0; i<m; i++) {
3190     row   = rstart + i;
3191     nz    = ii[i+1] - ii[i];
3192     cwork = jj;     jj += nz;
3193     vwork = aa;     aa += nz;
3194     ierr  = MatSetValues_MPIAIJ(M,1,&row,nz,cwork,vwork,INSERT_VALUES);CHKERRQ(ierr);
3195   }
3196 
3197   ierr    = MatAssemblyBegin(M,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
3198   ierr    = MatAssemblyEnd(M,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
3199   *newmat = M;
3200 
3201   /* save submatrix used in processor for next request */
3202   if (call ==  MAT_INITIAL_MATRIX) {
3203     ierr = PetscObjectCompose((PetscObject)M,"SubMatrix",(PetscObject)Mreuse);CHKERRQ(ierr);
3204     ierr = MatDestroy(&Mreuse);CHKERRQ(ierr);
3205   }
3206   PetscFunctionReturn(0);
3207 }
3208 
3209 #undef __FUNCT__
3210 #define __FUNCT__ "MatMPIAIJSetPreallocationCSR_MPIAIJ"
3211 PetscErrorCode  MatMPIAIJSetPreallocationCSR_MPIAIJ(Mat B,const PetscInt Ii[],const PetscInt J[],const PetscScalar v[])
3212 {
3213   PetscInt       m,cstart, cend,j,nnz,i,d;
3214   PetscInt       *d_nnz,*o_nnz,nnz_max = 0,rstart,ii;
3215   const PetscInt *JJ;
3216   PetscScalar    *values;
3217   PetscErrorCode ierr;
3218 
3219   PetscFunctionBegin;
3220   if (Ii[0]) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Ii[0] must be 0 it is %D",Ii[0]);
3221 
3222   ierr   = PetscLayoutSetUp(B->rmap);CHKERRQ(ierr);
3223   ierr   = PetscLayoutSetUp(B->cmap);CHKERRQ(ierr);
3224   m      = B->rmap->n;
3225   cstart = B->cmap->rstart;
3226   cend   = B->cmap->rend;
3227   rstart = B->rmap->rstart;
3228 
3229   ierr = PetscMalloc2(m,&d_nnz,m,&o_nnz);CHKERRQ(ierr);
3230 
3231 #if defined(PETSC_USE_DEBUGGING)
3232   for (i=0; i<m; i++) {
3233     nnz = Ii[i+1]- Ii[i];
3234     JJ  = J + Ii[i];
3235     if (nnz < 0) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Local row %D has a negative %D number of columns",i,nnz);
3236     if (nnz && (JJ[0] < 0)) SETERRRQ1(PETSC_ERR_ARG_WRONGSTATE,"Row %D starts with negative column index",i,j);
3237     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);
3238   }
3239 #endif
3240 
3241   for (i=0; i<m; i++) {
3242     nnz     = Ii[i+1]- Ii[i];
3243     JJ      = J + Ii[i];
3244     nnz_max = PetscMax(nnz_max,nnz);
3245     d       = 0;
3246     for (j=0; j<nnz; j++) {
3247       if (cstart <= JJ[j] && JJ[j] < cend) d++;
3248     }
3249     d_nnz[i] = d;
3250     o_nnz[i] = nnz - d;
3251   }
3252   ierr = MatMPIAIJSetPreallocation(B,0,d_nnz,0,o_nnz);CHKERRQ(ierr);
3253   ierr = PetscFree2(d_nnz,o_nnz);CHKERRQ(ierr);
3254 
3255   if (v) values = (PetscScalar*)v;
3256   else {
3257     ierr = PetscCalloc1(nnz_max+1,&values);CHKERRQ(ierr);
3258   }
3259 
3260   for (i=0; i<m; i++) {
3261     ii   = i + rstart;
3262     nnz  = Ii[i+1]- Ii[i];
3263     ierr = MatSetValues_MPIAIJ(B,1,&ii,nnz,J+Ii[i],values+(v ? Ii[i] : 0),INSERT_VALUES);CHKERRQ(ierr);
3264   }
3265   ierr = MatAssemblyBegin(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
3266   ierr = MatAssemblyEnd(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
3267 
3268   if (!v) {
3269     ierr = PetscFree(values);CHKERRQ(ierr);
3270   }
3271   ierr = MatSetOption(B,MAT_NEW_NONZERO_LOCATION_ERR,PETSC_TRUE);CHKERRQ(ierr);
3272   PetscFunctionReturn(0);
3273 }
3274 
3275 #undef __FUNCT__
3276 #define __FUNCT__ "MatMPIAIJSetPreallocationCSR"
3277 /*@
3278    MatMPIAIJSetPreallocationCSR - Allocates memory for a sparse parallel matrix in AIJ format
3279    (the default parallel PETSc format).
3280 
3281    Collective on MPI_Comm
3282 
3283    Input Parameters:
3284 +  B - the matrix
3285 .  i - the indices into j for the start of each local row (starts with zero)
3286 .  j - the column indices for each local row (starts with zero)
3287 -  v - optional values in the matrix
3288 
3289    Level: developer
3290 
3291    Notes:
3292        The i, j, and a arrays ARE copied by this routine into the internal format used by PETSc;
3293      thus you CANNOT change the matrix entries by changing the values of a[] after you have
3294      called this routine. Use MatCreateMPIAIJWithSplitArrays() to avoid needing to copy the arrays.
3295 
3296        The i and j indices are 0 based, and i indices are indices corresponding to the local j array.
3297 
3298        The format which is used for the sparse matrix input, is equivalent to a
3299     row-major ordering.. i.e for the following matrix, the input data expected is
3300     as shown
3301 
3302 $        1 0 0
3303 $        2 0 3     P0
3304 $       -------
3305 $        4 5 6     P1
3306 $
3307 $     Process0 [P0]: rows_owned=[0,1]
3308 $        i =  {0,1,3}  [size = nrow+1  = 2+1]
3309 $        j =  {0,0,2}  [size = 3]
3310 $        v =  {1,2,3}  [size = 3]
3311 $
3312 $     Process1 [P1]: rows_owned=[2]
3313 $        i =  {0,3}    [size = nrow+1  = 1+1]
3314 $        j =  {0,1,2}  [size = 3]
3315 $        v =  {4,5,6}  [size = 3]
3316 
3317 .keywords: matrix, aij, compressed row, sparse, parallel
3318 
3319 .seealso: MatCreate(), MatCreateSeqAIJ(), MatSetValues(), MatMPIAIJSetPreallocation(), MatCreateAIJ(), MPIAIJ,
3320           MatCreateSeqAIJWithArrays(), MatCreateMPIAIJWithSplitArrays()
3321 @*/
3322 PetscErrorCode  MatMPIAIJSetPreallocationCSR(Mat B,const PetscInt i[],const PetscInt j[], const PetscScalar v[])
3323 {
3324   PetscErrorCode ierr;
3325 
3326   PetscFunctionBegin;
3327   ierr = PetscTryMethod(B,"MatMPIAIJSetPreallocationCSR_C",(Mat,const PetscInt[],const PetscInt[],const PetscScalar[]),(B,i,j,v));CHKERRQ(ierr);
3328   PetscFunctionReturn(0);
3329 }
3330 
3331 #undef __FUNCT__
3332 #define __FUNCT__ "MatMPIAIJSetPreallocation"
3333 /*@C
3334    MatMPIAIJSetPreallocation - Preallocates memory for a sparse parallel matrix in AIJ format
3335    (the default parallel PETSc format).  For good matrix assembly performance
3336    the user should preallocate the matrix storage by setting the parameters
3337    d_nz (or d_nnz) and o_nz (or o_nnz).  By setting these parameters accurately,
3338    performance can be increased by more than a factor of 50.
3339 
3340    Collective on MPI_Comm
3341 
3342    Input Parameters:
3343 +  B - the matrix
3344 .  d_nz  - number of nonzeros per row in DIAGONAL portion of local submatrix
3345            (same value is used for all local rows)
3346 .  d_nnz - array containing the number of nonzeros in the various rows of the
3347            DIAGONAL portion of the local submatrix (possibly different for each row)
3348            or NULL (PETSC_NULL_INTEGER in Fortran), if d_nz is used to specify the nonzero structure.
3349            The size of this array is equal to the number of local rows, i.e 'm'.
3350            For matrices that will be factored, you must leave room for (and set)
3351            the diagonal entry even if it is zero.
3352 .  o_nz  - number of nonzeros per row in the OFF-DIAGONAL portion of local
3353            submatrix (same value is used for all local rows).
3354 -  o_nnz - array containing the number of nonzeros in the various rows of the
3355            OFF-DIAGONAL portion of the local submatrix (possibly different for
3356            each row) or NULL (PETSC_NULL_INTEGER in Fortran), if o_nz is used to specify the nonzero
3357            structure. The size of this array is equal to the number
3358            of local rows, i.e 'm'.
3359 
3360    If the *_nnz parameter is given then the *_nz parameter is ignored
3361 
3362    The AIJ format (also called the Yale sparse matrix format or
3363    compressed row storage (CSR)), is fully compatible with standard Fortran 77
3364    storage.  The stored row and column indices begin with zero.
3365    See Users-Manual: ch_mat for details.
3366 
3367    The parallel matrix is partitioned such that the first m0 rows belong to
3368    process 0, the next m1 rows belong to process 1, the next m2 rows belong
3369    to process 2 etc.. where m0,m1,m2... are the input parameter 'm'.
3370 
3371    The DIAGONAL portion of the local submatrix of a processor can be defined
3372    as the submatrix which is obtained by extraction the part corresponding to
3373    the rows r1-r2 and columns c1-c2 of the global matrix, where r1 is the
3374    first row that belongs to the processor, r2 is the last row belonging to
3375    the this processor, and c1-c2 is range of indices of the local part of a
3376    vector suitable for applying the matrix to.  This is an mxn matrix.  In the
3377    common case of a square matrix, the row and column ranges are the same and
3378    the DIAGONAL part is also square. The remaining portion of the local
3379    submatrix (mxN) constitute the OFF-DIAGONAL portion.
3380 
3381    If o_nnz, d_nnz are specified, then o_nz, and d_nz are ignored.
3382 
3383    You can call MatGetInfo() to get information on how effective the preallocation was;
3384    for example the fields mallocs,nz_allocated,nz_used,nz_unneeded;
3385    You can also run with the option -info and look for messages with the string
3386    malloc in them to see if additional memory allocation was needed.
3387 
3388    Example usage:
3389 
3390    Consider the following 8x8 matrix with 34 non-zero values, that is
3391    assembled across 3 processors. Lets assume that proc0 owns 3 rows,
3392    proc1 owns 3 rows, proc2 owns 2 rows. This division can be shown
3393    as follows:
3394 
3395 .vb
3396             1  2  0  |  0  3  0  |  0  4
3397     Proc0   0  5  6  |  7  0  0  |  8  0
3398             9  0 10  | 11  0  0  | 12  0
3399     -------------------------------------
3400            13  0 14  | 15 16 17  |  0  0
3401     Proc1   0 18  0  | 19 20 21  |  0  0
3402             0  0  0  | 22 23  0  | 24  0
3403     -------------------------------------
3404     Proc2  25 26 27  |  0  0 28  | 29  0
3405            30  0  0  | 31 32 33  |  0 34
3406 .ve
3407 
3408    This can be represented as a collection of submatrices as:
3409 
3410 .vb
3411       A B C
3412       D E F
3413       G H I
3414 .ve
3415 
3416    Where the submatrices A,B,C are owned by proc0, D,E,F are
3417    owned by proc1, G,H,I are owned by proc2.
3418 
3419    The 'm' parameters for proc0,proc1,proc2 are 3,3,2 respectively.
3420    The 'n' parameters for proc0,proc1,proc2 are 3,3,2 respectively.
3421    The 'M','N' parameters are 8,8, and have the same values on all procs.
3422 
3423    The DIAGONAL submatrices corresponding to proc0,proc1,proc2 are
3424    submatrices [A], [E], [I] respectively. The OFF-DIAGONAL submatrices
3425    corresponding to proc0,proc1,proc2 are [BC], [DF], [GH] respectively.
3426    Internally, each processor stores the DIAGONAL part, and the OFF-DIAGONAL
3427    part as SeqAIJ matrices. for eg: proc1 will store [E] as a SeqAIJ
3428    matrix, ans [DF] as another SeqAIJ matrix.
3429 
3430    When d_nz, o_nz parameters are specified, d_nz storage elements are
3431    allocated for every row of the local diagonal submatrix, and o_nz
3432    storage locations are allocated for every row of the OFF-DIAGONAL submat.
3433    One way to choose d_nz and o_nz is to use the max nonzerors per local
3434    rows for each of the local DIAGONAL, and the OFF-DIAGONAL submatrices.
3435    In this case, the values of d_nz,o_nz are:
3436 .vb
3437      proc0 : dnz = 2, o_nz = 2
3438      proc1 : dnz = 3, o_nz = 2
3439      proc2 : dnz = 1, o_nz = 4
3440 .ve
3441    We are allocating m*(d_nz+o_nz) storage locations for every proc. This
3442    translates to 3*(2+2)=12 for proc0, 3*(3+2)=15 for proc1, 2*(1+4)=10
3443    for proc3. i.e we are using 12+15+10=37 storage locations to store
3444    34 values.
3445 
3446    When d_nnz, o_nnz parameters are specified, the storage is specified
3447    for every row, coresponding to both DIAGONAL and OFF-DIAGONAL submatrices.
3448    In the above case the values for d_nnz,o_nnz are:
3449 .vb
3450      proc0: d_nnz = [2,2,2] and o_nnz = [2,2,2]
3451      proc1: d_nnz = [3,3,2] and o_nnz = [2,1,1]
3452      proc2: d_nnz = [1,1]   and o_nnz = [4,4]
3453 .ve
3454    Here the space allocated is sum of all the above values i.e 34, and
3455    hence pre-allocation is perfect.
3456 
3457    Level: intermediate
3458 
3459 .keywords: matrix, aij, compressed row, sparse, parallel
3460 
3461 .seealso: MatCreate(), MatCreateSeqAIJ(), MatSetValues(), MatCreateAIJ(), MatMPIAIJSetPreallocationCSR(),
3462           MPIAIJ, MatGetInfo(), PetscSplitOwnership()
3463 @*/
3464 PetscErrorCode  MatMPIAIJSetPreallocation(Mat B,PetscInt d_nz,const PetscInt d_nnz[],PetscInt o_nz,const PetscInt o_nnz[])
3465 {
3466   PetscErrorCode ierr;
3467 
3468   PetscFunctionBegin;
3469   PetscValidHeaderSpecific(B,MAT_CLASSID,1);
3470   PetscValidType(B,1);
3471   ierr = PetscTryMethod(B,"MatMPIAIJSetPreallocation_C",(Mat,PetscInt,const PetscInt[],PetscInt,const PetscInt[]),(B,d_nz,d_nnz,o_nz,o_nnz));CHKERRQ(ierr);
3472   PetscFunctionReturn(0);
3473 }
3474 
3475 #undef __FUNCT__
3476 #define __FUNCT__ "MatCreateMPIAIJWithArrays"
3477 /*@
3478      MatCreateMPIAIJWithArrays - creates a MPI AIJ matrix using arrays that contain in standard
3479          CSR format the local rows.
3480 
3481    Collective on MPI_Comm
3482 
3483    Input Parameters:
3484 +  comm - MPI communicator
3485 .  m - number of local rows (Cannot be PETSC_DECIDE)
3486 .  n - This value should be the same as the local size used in creating the
3487        x vector for the matrix-vector product y = Ax. (or PETSC_DECIDE to have
3488        calculated if N is given) For square matrices n is almost always m.
3489 .  M - number of global rows (or PETSC_DETERMINE to have calculated if m is given)
3490 .  N - number of global columns (or PETSC_DETERMINE to have calculated if n is given)
3491 .   i - row indices
3492 .   j - column indices
3493 -   a - matrix values
3494 
3495    Output Parameter:
3496 .   mat - the matrix
3497 
3498    Level: intermediate
3499 
3500    Notes:
3501        The i, j, and a arrays ARE copied by this routine into the internal format used by PETSc;
3502      thus you CANNOT change the matrix entries by changing the values of a[] after you have
3503      called this routine. Use MatCreateMPIAIJWithSplitArrays() to avoid needing to copy the arrays.
3504 
3505        The i and j indices are 0 based, and i indices are indices corresponding to the local j array.
3506 
3507        The format which is used for the sparse matrix input, is equivalent to a
3508     row-major ordering.. i.e for the following matrix, the input data expected is
3509     as shown
3510 
3511 $        1 0 0
3512 $        2 0 3     P0
3513 $       -------
3514 $        4 5 6     P1
3515 $
3516 $     Process0 [P0]: rows_owned=[0,1]
3517 $        i =  {0,1,3}  [size = nrow+1  = 2+1]
3518 $        j =  {0,0,2}  [size = 3]
3519 $        v =  {1,2,3}  [size = 3]
3520 $
3521 $     Process1 [P1]: rows_owned=[2]
3522 $        i =  {0,3}    [size = nrow+1  = 1+1]
3523 $        j =  {0,1,2}  [size = 3]
3524 $        v =  {4,5,6}  [size = 3]
3525 
3526 .keywords: matrix, aij, compressed row, sparse, parallel
3527 
3528 .seealso: MatCreate(), MatCreateSeqAIJ(), MatSetValues(), MatMPIAIJSetPreallocation(), MatMPIAIJSetPreallocationCSR(),
3529           MPIAIJ, MatCreateAIJ(), MatCreateMPIAIJWithSplitArrays()
3530 @*/
3531 PetscErrorCode  MatCreateMPIAIJWithArrays(MPI_Comm comm,PetscInt m,PetscInt n,PetscInt M,PetscInt N,const PetscInt i[],const PetscInt j[],const PetscScalar a[],Mat *mat)
3532 {
3533   PetscErrorCode ierr;
3534 
3535   PetscFunctionBegin;
3536   if (i[0]) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"i (row indices) must start with 0");
3537   if (m < 0) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"local number of rows (m) cannot be PETSC_DECIDE, or negative");
3538   ierr = MatCreate(comm,mat);CHKERRQ(ierr);
3539   ierr = MatSetSizes(*mat,m,n,M,N);CHKERRQ(ierr);
3540   /* ierr = MatSetBlockSizes(M,bs,cbs);CHKERRQ(ierr); */
3541   ierr = MatSetType(*mat,MATMPIAIJ);CHKERRQ(ierr);
3542   ierr = MatMPIAIJSetPreallocationCSR(*mat,i,j,a);CHKERRQ(ierr);
3543   PetscFunctionReturn(0);
3544 }
3545 
3546 #undef __FUNCT__
3547 #define __FUNCT__ "MatCreateAIJ"
3548 /*@C
3549    MatCreateAIJ - Creates a sparse parallel matrix in AIJ format
3550    (the default parallel PETSc format).  For good matrix assembly performance
3551    the user should preallocate the matrix storage by setting the parameters
3552    d_nz (or d_nnz) and o_nz (or o_nnz).  By setting these parameters accurately,
3553    performance can be increased by more than a factor of 50.
3554 
3555    Collective on MPI_Comm
3556 
3557    Input Parameters:
3558 +  comm - MPI communicator
3559 .  m - number of local rows (or PETSC_DECIDE to have calculated if M is given)
3560            This value should be the same as the local size used in creating the
3561            y vector for the matrix-vector product y = Ax.
3562 .  n - This value should be the same as the local size used in creating the
3563        x vector for the matrix-vector product y = Ax. (or PETSC_DECIDE to have
3564        calculated if N is given) For square matrices n is almost always m.
3565 .  M - number of global rows (or PETSC_DETERMINE to have calculated if m is given)
3566 .  N - number of global columns (or PETSC_DETERMINE to have calculated if n is given)
3567 .  d_nz  - number of nonzeros per row in DIAGONAL portion of local submatrix
3568            (same value is used for all local rows)
3569 .  d_nnz - array containing the number of nonzeros in the various rows of the
3570            DIAGONAL portion of the local submatrix (possibly different for each row)
3571            or NULL, if d_nz is used to specify the nonzero structure.
3572            The size of this array is equal to the number of local rows, i.e 'm'.
3573 .  o_nz  - number of nonzeros per row in the OFF-DIAGONAL portion of local
3574            submatrix (same value is used for all local rows).
3575 -  o_nnz - array containing the number of nonzeros in the various rows of the
3576            OFF-DIAGONAL portion of the local submatrix (possibly different for
3577            each row) or NULL, if o_nz is used to specify the nonzero
3578            structure. The size of this array is equal to the number
3579            of local rows, i.e 'm'.
3580 
3581    Output Parameter:
3582 .  A - the matrix
3583 
3584    It is recommended that one use the MatCreate(), MatSetType() and/or MatSetFromOptions(),
3585    MatXXXXSetPreallocation() paradgm instead of this routine directly.
3586    [MatXXXXSetPreallocation() is, for example, MatSeqAIJSetPreallocation]
3587 
3588    Notes:
3589    If the *_nnz parameter is given then the *_nz parameter is ignored
3590 
3591    m,n,M,N parameters specify the size of the matrix, and its partitioning across
3592    processors, while d_nz,d_nnz,o_nz,o_nnz parameters specify the approximate
3593    storage requirements for this matrix.
3594 
3595    If PETSC_DECIDE or  PETSC_DETERMINE is used for a particular argument on one
3596    processor than it must be used on all processors that share the object for
3597    that argument.
3598 
3599    The user MUST specify either the local or global matrix dimensions
3600    (possibly both).
3601 
3602    The parallel matrix is partitioned across processors such that the
3603    first m0 rows belong to process 0, the next m1 rows belong to
3604    process 1, the next m2 rows belong to process 2 etc.. where
3605    m0,m1,m2,.. are the input parameter 'm'. i.e each processor stores
3606    values corresponding to [m x N] submatrix.
3607 
3608    The columns are logically partitioned with the n0 columns belonging
3609    to 0th partition, the next n1 columns belonging to the next
3610    partition etc.. where n0,n1,n2... are the input parameter 'n'.
3611 
3612    The DIAGONAL portion of the local submatrix on any given processor
3613    is the submatrix corresponding to the rows and columns m,n
3614    corresponding to the given processor. i.e diagonal matrix on
3615    process 0 is [m0 x n0], diagonal matrix on process 1 is [m1 x n1]
3616    etc. The remaining portion of the local submatrix [m x (N-n)]
3617    constitute the OFF-DIAGONAL portion. The example below better
3618    illustrates this concept.
3619 
3620    For a square global matrix we define each processor's diagonal portion
3621    to be its local rows and the corresponding columns (a square submatrix);
3622    each processor's off-diagonal portion encompasses the remainder of the
3623    local matrix (a rectangular submatrix).
3624 
3625    If o_nnz, d_nnz are specified, then o_nz, and d_nz are ignored.
3626 
3627    When calling this routine with a single process communicator, a matrix of
3628    type SEQAIJ is returned.  If a matrix of type MPIAIJ is desired for this
3629    type of communicator, use the construction mechanism:
3630      MatCreate(...,&A); MatSetType(A,MATMPIAIJ); MatSetSizes(A, m,n,M,N); MatMPIAIJSetPreallocation(A,...);
3631 
3632    By default, this format uses inodes (identical nodes) when possible.
3633    We search for consecutive rows with the same nonzero structure, thereby
3634    reusing matrix information to achieve increased efficiency.
3635 
3636    Options Database Keys:
3637 +  -mat_no_inode  - Do not use inodes
3638 .  -mat_inode_limit <limit> - Sets inode limit (max limit=5)
3639 -  -mat_aij_oneindex - Internally use indexing starting at 1
3640         rather than 0.  Note that when calling MatSetValues(),
3641         the user still MUST index entries starting at 0!
3642 
3643 
3644    Example usage:
3645 
3646    Consider the following 8x8 matrix with 34 non-zero values, that is
3647    assembled across 3 processors. Lets assume that proc0 owns 3 rows,
3648    proc1 owns 3 rows, proc2 owns 2 rows. This division can be shown
3649    as follows:
3650 
3651 .vb
3652             1  2  0  |  0  3  0  |  0  4
3653     Proc0   0  5  6  |  7  0  0  |  8  0
3654             9  0 10  | 11  0  0  | 12  0
3655     -------------------------------------
3656            13  0 14  | 15 16 17  |  0  0
3657     Proc1   0 18  0  | 19 20 21  |  0  0
3658             0  0  0  | 22 23  0  | 24  0
3659     -------------------------------------
3660     Proc2  25 26 27  |  0  0 28  | 29  0
3661            30  0  0  | 31 32 33  |  0 34
3662 .ve
3663 
3664    This can be represented as a collection of submatrices as:
3665 
3666 .vb
3667       A B C
3668       D E F
3669       G H I
3670 .ve
3671 
3672    Where the submatrices A,B,C are owned by proc0, D,E,F are
3673    owned by proc1, G,H,I are owned by proc2.
3674 
3675    The 'm' parameters for proc0,proc1,proc2 are 3,3,2 respectively.
3676    The 'n' parameters for proc0,proc1,proc2 are 3,3,2 respectively.
3677    The 'M','N' parameters are 8,8, and have the same values on all procs.
3678 
3679    The DIAGONAL submatrices corresponding to proc0,proc1,proc2 are
3680    submatrices [A], [E], [I] respectively. The OFF-DIAGONAL submatrices
3681    corresponding to proc0,proc1,proc2 are [BC], [DF], [GH] respectively.
3682    Internally, each processor stores the DIAGONAL part, and the OFF-DIAGONAL
3683    part as SeqAIJ matrices. for eg: proc1 will store [E] as a SeqAIJ
3684    matrix, ans [DF] as another SeqAIJ matrix.
3685 
3686    When d_nz, o_nz parameters are specified, d_nz storage elements are
3687    allocated for every row of the local diagonal submatrix, and o_nz
3688    storage locations are allocated for every row of the OFF-DIAGONAL submat.
3689    One way to choose d_nz and o_nz is to use the max nonzerors per local
3690    rows for each of the local DIAGONAL, and the OFF-DIAGONAL submatrices.
3691    In this case, the values of d_nz,o_nz are:
3692 .vb
3693      proc0 : dnz = 2, o_nz = 2
3694      proc1 : dnz = 3, o_nz = 2
3695      proc2 : dnz = 1, o_nz = 4
3696 .ve
3697    We are allocating m*(d_nz+o_nz) storage locations for every proc. This
3698    translates to 3*(2+2)=12 for proc0, 3*(3+2)=15 for proc1, 2*(1+4)=10
3699    for proc3. i.e we are using 12+15+10=37 storage locations to store
3700    34 values.
3701 
3702    When d_nnz, o_nnz parameters are specified, the storage is specified
3703    for every row, coresponding to both DIAGONAL and OFF-DIAGONAL submatrices.
3704    In the above case the values for d_nnz,o_nnz are:
3705 .vb
3706      proc0: d_nnz = [2,2,2] and o_nnz = [2,2,2]
3707      proc1: d_nnz = [3,3,2] and o_nnz = [2,1,1]
3708      proc2: d_nnz = [1,1]   and o_nnz = [4,4]
3709 .ve
3710    Here the space allocated is sum of all the above values i.e 34, and
3711    hence pre-allocation is perfect.
3712 
3713    Level: intermediate
3714 
3715 .keywords: matrix, aij, compressed row, sparse, parallel
3716 
3717 .seealso: MatCreate(), MatCreateSeqAIJ(), MatSetValues(), MatMPIAIJSetPreallocation(), MatMPIAIJSetPreallocationCSR(),
3718           MPIAIJ, MatCreateMPIAIJWithArrays()
3719 @*/
3720 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)
3721 {
3722   PetscErrorCode ierr;
3723   PetscMPIInt    size;
3724 
3725   PetscFunctionBegin;
3726   ierr = MatCreate(comm,A);CHKERRQ(ierr);
3727   ierr = MatSetSizes(*A,m,n,M,N);CHKERRQ(ierr);
3728   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
3729   if (size > 1) {
3730     ierr = MatSetType(*A,MATMPIAIJ);CHKERRQ(ierr);
3731     ierr = MatMPIAIJSetPreallocation(*A,d_nz,d_nnz,o_nz,o_nnz);CHKERRQ(ierr);
3732   } else {
3733     ierr = MatSetType(*A,MATSEQAIJ);CHKERRQ(ierr);
3734     ierr = MatSeqAIJSetPreallocation(*A,d_nz,d_nnz);CHKERRQ(ierr);
3735   }
3736   PetscFunctionReturn(0);
3737 }
3738 
3739 #undef __FUNCT__
3740 #define __FUNCT__ "MatMPIAIJGetSeqAIJ"
3741 PetscErrorCode  MatMPIAIJGetSeqAIJ(Mat A,Mat *Ad,Mat *Ao,const PetscInt *colmap[])
3742 {
3743   Mat_MPIAIJ *a = (Mat_MPIAIJ*)A->data;
3744 
3745   PetscFunctionBegin;
3746   if (Ad)     *Ad     = a->A;
3747   if (Ao)     *Ao     = a->B;
3748   if (colmap) *colmap = a->garray;
3749   PetscFunctionReturn(0);
3750 }
3751 
3752 #undef __FUNCT__
3753 #define __FUNCT__ "MatSetColoring_MPIAIJ"
3754 PetscErrorCode MatSetColoring_MPIAIJ(Mat A,ISColoring coloring)
3755 {
3756   PetscErrorCode ierr;
3757   PetscInt       i;
3758   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
3759 
3760   PetscFunctionBegin;
3761   if (coloring->ctype == IS_COLORING_GLOBAL) {
3762     ISColoringValue *allcolors,*colors;
3763     ISColoring      ocoloring;
3764 
3765     /* set coloring for diagonal portion */
3766     ierr = MatSetColoring_SeqAIJ(a->A,coloring);CHKERRQ(ierr);
3767 
3768     /* set coloring for off-diagonal portion */
3769     ierr = ISAllGatherColors(PetscObjectComm((PetscObject)A),coloring->n,coloring->colors,NULL,&allcolors);CHKERRQ(ierr);
3770     ierr = PetscMalloc1(a->B->cmap->n+1,&colors);CHKERRQ(ierr);
3771     for (i=0; i<a->B->cmap->n; i++) {
3772       colors[i] = allcolors[a->garray[i]];
3773     }
3774     ierr = PetscFree(allcolors);CHKERRQ(ierr);
3775     ierr = ISColoringCreate(MPI_COMM_SELF,coloring->n,a->B->cmap->n,colors,PETSC_OWN_POINTER,&ocoloring);CHKERRQ(ierr);
3776     ierr = MatSetColoring_SeqAIJ(a->B,ocoloring);CHKERRQ(ierr);
3777     ierr = ISColoringDestroy(&ocoloring);CHKERRQ(ierr);
3778   } else if (coloring->ctype == IS_COLORING_GHOSTED) {
3779     ISColoringValue *colors;
3780     PetscInt        *larray;
3781     ISColoring      ocoloring;
3782 
3783     /* set coloring for diagonal portion */
3784     ierr = PetscMalloc1(a->A->cmap->n+1,&larray);CHKERRQ(ierr);
3785     for (i=0; i<a->A->cmap->n; i++) {
3786       larray[i] = i + A->cmap->rstart;
3787     }
3788     ierr = ISGlobalToLocalMappingApply(A->cmap->mapping,IS_GTOLM_MASK,a->A->cmap->n,larray,NULL,larray);CHKERRQ(ierr);
3789     ierr = PetscMalloc1(a->A->cmap->n+1,&colors);CHKERRQ(ierr);
3790     for (i=0; i<a->A->cmap->n; i++) {
3791       colors[i] = coloring->colors[larray[i]];
3792     }
3793     ierr = PetscFree(larray);CHKERRQ(ierr);
3794     ierr = ISColoringCreate(PETSC_COMM_SELF,coloring->n,a->A->cmap->n,colors,PETSC_OWN_POINTER,&ocoloring);CHKERRQ(ierr);
3795     ierr = MatSetColoring_SeqAIJ(a->A,ocoloring);CHKERRQ(ierr);
3796     ierr = ISColoringDestroy(&ocoloring);CHKERRQ(ierr);
3797 
3798     /* set coloring for off-diagonal portion */
3799     ierr = PetscMalloc1(a->B->cmap->n+1,&larray);CHKERRQ(ierr);
3800     ierr = ISGlobalToLocalMappingApply(A->cmap->mapping,IS_GTOLM_MASK,a->B->cmap->n,a->garray,NULL,larray);CHKERRQ(ierr);
3801     ierr = PetscMalloc1(a->B->cmap->n+1,&colors);CHKERRQ(ierr);
3802     for (i=0; i<a->B->cmap->n; i++) {
3803       colors[i] = coloring->colors[larray[i]];
3804     }
3805     ierr = PetscFree(larray);CHKERRQ(ierr);
3806     ierr = ISColoringCreate(MPI_COMM_SELF,coloring->n,a->B->cmap->n,colors,PETSC_OWN_POINTER,&ocoloring);CHKERRQ(ierr);
3807     ierr = MatSetColoring_SeqAIJ(a->B,ocoloring);CHKERRQ(ierr);
3808     ierr = ISColoringDestroy(&ocoloring);CHKERRQ(ierr);
3809   } else SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_SUP,"No support ISColoringType %d",(int)coloring->ctype);
3810   PetscFunctionReturn(0);
3811 }
3812 
3813 #undef __FUNCT__
3814 #define __FUNCT__ "MatSetValuesAdifor_MPIAIJ"
3815 PetscErrorCode MatSetValuesAdifor_MPIAIJ(Mat A,PetscInt nl,void *advalues)
3816 {
3817   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
3818   PetscErrorCode ierr;
3819 
3820   PetscFunctionBegin;
3821   ierr = MatSetValuesAdifor_SeqAIJ(a->A,nl,advalues);CHKERRQ(ierr);
3822   ierr = MatSetValuesAdifor_SeqAIJ(a->B,nl,advalues);CHKERRQ(ierr);
3823   PetscFunctionReturn(0);
3824 }
3825 
3826 #undef __FUNCT__
3827 #define __FUNCT__ "MatCreateMPIMatConcatenateSeqMat_MPIAIJ"
3828 PetscErrorCode MatCreateMPIMatConcatenateSeqMat_MPIAIJ(MPI_Comm comm,Mat inmat,PetscInt n,MatReuse scall,Mat *outmat)
3829 {
3830   PetscErrorCode ierr;
3831   PetscInt       m,N,i,rstart,nnz,Ii;
3832   PetscInt       *indx;
3833   PetscScalar    *values;
3834 
3835   PetscFunctionBegin;
3836   ierr = MatGetSize(inmat,&m,&N);CHKERRQ(ierr);
3837   if (scall == MAT_INITIAL_MATRIX) { /* symbolic phase */
3838     PetscInt       *dnz,*onz,sum,bs,cbs;
3839 
3840     if (n == PETSC_DECIDE) {
3841       ierr = PetscSplitOwnership(comm,&n,&N);CHKERRQ(ierr);
3842     }
3843     /* Check sum(n) = N */
3844     ierr = MPIU_Allreduce(&n,&sum,1,MPIU_INT,MPI_SUM,comm);CHKERRQ(ierr);
3845     if (sum != N) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_INCOMP,"Sum of local columns != global columns %d",N);
3846 
3847     ierr    = MPI_Scan(&m, &rstart,1,MPIU_INT,MPI_SUM,comm);CHKERRQ(ierr);
3848     rstart -= m;
3849 
3850     ierr = MatPreallocateInitialize(comm,m,n,dnz,onz);CHKERRQ(ierr);
3851     for (i=0; i<m; i++) {
3852       ierr = MatGetRow_SeqAIJ(inmat,i,&nnz,&indx,NULL);CHKERRQ(ierr);
3853       ierr = MatPreallocateSet(i+rstart,nnz,indx,dnz,onz);CHKERRQ(ierr);
3854       ierr = MatRestoreRow_SeqAIJ(inmat,i,&nnz,&indx,NULL);CHKERRQ(ierr);
3855     }
3856 
3857     ierr = MatCreate(comm,outmat);CHKERRQ(ierr);
3858     ierr = MatSetSizes(*outmat,m,n,PETSC_DETERMINE,PETSC_DETERMINE);CHKERRQ(ierr);
3859     ierr = MatGetBlockSizes(inmat,&bs,&cbs);CHKERRQ(ierr);
3860     ierr = MatSetBlockSizes(*outmat,bs,cbs);CHKERRQ(ierr);
3861     ierr = MatSetType(*outmat,MATMPIAIJ);CHKERRQ(ierr);
3862     ierr = MatMPIAIJSetPreallocation(*outmat,0,dnz,0,onz);CHKERRQ(ierr);
3863     ierr = MatPreallocateFinalize(dnz,onz);CHKERRQ(ierr);
3864   }
3865 
3866   /* numeric phase */
3867   ierr = MatGetOwnershipRange(*outmat,&rstart,NULL);CHKERRQ(ierr);
3868   for (i=0; i<m; i++) {
3869     ierr = MatGetRow_SeqAIJ(inmat,i,&nnz,&indx,&values);CHKERRQ(ierr);
3870     Ii   = i + rstart;
3871     ierr = MatSetValues(*outmat,1,&Ii,nnz,indx,values,INSERT_VALUES);CHKERRQ(ierr);
3872     ierr = MatRestoreRow_SeqAIJ(inmat,i,&nnz,&indx,&values);CHKERRQ(ierr);
3873   }
3874   ierr = MatAssemblyBegin(*outmat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
3875   ierr = MatAssemblyEnd(*outmat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
3876   PetscFunctionReturn(0);
3877 }
3878 
3879 #undef __FUNCT__
3880 #define __FUNCT__ "MatFileSplit"
3881 PetscErrorCode MatFileSplit(Mat A,char *outfile)
3882 {
3883   PetscErrorCode    ierr;
3884   PetscMPIInt       rank;
3885   PetscInt          m,N,i,rstart,nnz;
3886   size_t            len;
3887   const PetscInt    *indx;
3888   PetscViewer       out;
3889   char              *name;
3890   Mat               B;
3891   const PetscScalar *values;
3892 
3893   PetscFunctionBegin;
3894   ierr = MatGetLocalSize(A,&m,0);CHKERRQ(ierr);
3895   ierr = MatGetSize(A,0,&N);CHKERRQ(ierr);
3896   /* Should this be the type of the diagonal block of A? */
3897   ierr = MatCreate(PETSC_COMM_SELF,&B);CHKERRQ(ierr);
3898   ierr = MatSetSizes(B,m,N,m,N);CHKERRQ(ierr);
3899   ierr = MatSetBlockSizesFromMats(B,A,A);CHKERRQ(ierr);
3900   ierr = MatSetType(B,MATSEQAIJ);CHKERRQ(ierr);
3901   ierr = MatSeqAIJSetPreallocation(B,0,NULL);CHKERRQ(ierr);
3902   ierr = MatGetOwnershipRange(A,&rstart,0);CHKERRQ(ierr);
3903   for (i=0; i<m; i++) {
3904     ierr = MatGetRow(A,i+rstart,&nnz,&indx,&values);CHKERRQ(ierr);
3905     ierr = MatSetValues(B,1,&i,nnz,indx,values,INSERT_VALUES);CHKERRQ(ierr);
3906     ierr = MatRestoreRow(A,i+rstart,&nnz,&indx,&values);CHKERRQ(ierr);
3907   }
3908   ierr = MatAssemblyBegin(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
3909   ierr = MatAssemblyEnd(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
3910 
3911   ierr = MPI_Comm_rank(PetscObjectComm((PetscObject)A),&rank);CHKERRQ(ierr);
3912   ierr = PetscStrlen(outfile,&len);CHKERRQ(ierr);
3913   ierr = PetscMalloc1(len+5,&name);CHKERRQ(ierr);
3914   sprintf(name,"%s.%d",outfile,rank);
3915   ierr = PetscViewerBinaryOpen(PETSC_COMM_SELF,name,FILE_MODE_APPEND,&out);CHKERRQ(ierr);
3916   ierr = PetscFree(name);CHKERRQ(ierr);
3917   ierr = MatView(B,out);CHKERRQ(ierr);
3918   ierr = PetscViewerDestroy(&out);CHKERRQ(ierr);
3919   ierr = MatDestroy(&B);CHKERRQ(ierr);
3920   PetscFunctionReturn(0);
3921 }
3922 
3923 extern PetscErrorCode MatDestroy_MPIAIJ(Mat);
3924 #undef __FUNCT__
3925 #define __FUNCT__ "MatDestroy_MPIAIJ_SeqsToMPI"
3926 PetscErrorCode  MatDestroy_MPIAIJ_SeqsToMPI(Mat A)
3927 {
3928   PetscErrorCode      ierr;
3929   Mat_Merge_SeqsToMPI *merge;
3930   PetscContainer      container;
3931 
3932   PetscFunctionBegin;
3933   ierr = PetscObjectQuery((PetscObject)A,"MatMergeSeqsToMPI",(PetscObject*)&container);CHKERRQ(ierr);
3934   if (container) {
3935     ierr = PetscContainerGetPointer(container,(void**)&merge);CHKERRQ(ierr);
3936     ierr = PetscFree(merge->id_r);CHKERRQ(ierr);
3937     ierr = PetscFree(merge->len_s);CHKERRQ(ierr);
3938     ierr = PetscFree(merge->len_r);CHKERRQ(ierr);
3939     ierr = PetscFree(merge->bi);CHKERRQ(ierr);
3940     ierr = PetscFree(merge->bj);CHKERRQ(ierr);
3941     ierr = PetscFree(merge->buf_ri[0]);CHKERRQ(ierr);
3942     ierr = PetscFree(merge->buf_ri);CHKERRQ(ierr);
3943     ierr = PetscFree(merge->buf_rj[0]);CHKERRQ(ierr);
3944     ierr = PetscFree(merge->buf_rj);CHKERRQ(ierr);
3945     ierr = PetscFree(merge->coi);CHKERRQ(ierr);
3946     ierr = PetscFree(merge->coj);CHKERRQ(ierr);
3947     ierr = PetscFree(merge->owners_co);CHKERRQ(ierr);
3948     ierr = PetscLayoutDestroy(&merge->rowmap);CHKERRQ(ierr);
3949     ierr = PetscFree(merge);CHKERRQ(ierr);
3950     ierr = PetscObjectCompose((PetscObject)A,"MatMergeSeqsToMPI",0);CHKERRQ(ierr);
3951   }
3952   ierr = MatDestroy_MPIAIJ(A);CHKERRQ(ierr);
3953   PetscFunctionReturn(0);
3954 }
3955 
3956 #include <../src/mat/utils/freespace.h>
3957 #include <petscbt.h>
3958 
3959 #undef __FUNCT__
3960 #define __FUNCT__ "MatCreateMPIAIJSumSeqAIJNumeric"
3961 PetscErrorCode  MatCreateMPIAIJSumSeqAIJNumeric(Mat seqmat,Mat mpimat)
3962 {
3963   PetscErrorCode      ierr;
3964   MPI_Comm            comm;
3965   Mat_SeqAIJ          *a  =(Mat_SeqAIJ*)seqmat->data;
3966   PetscMPIInt         size,rank,taga,*len_s;
3967   PetscInt            N=mpimat->cmap->N,i,j,*owners,*ai=a->i,*aj;
3968   PetscInt            proc,m;
3969   PetscInt            **buf_ri,**buf_rj;
3970   PetscInt            k,anzi,*bj_i,*bi,*bj,arow,bnzi,nextaj;
3971   PetscInt            nrows,**buf_ri_k,**nextrow,**nextai;
3972   MPI_Request         *s_waits,*r_waits;
3973   MPI_Status          *status;
3974   MatScalar           *aa=a->a;
3975   MatScalar           **abuf_r,*ba_i;
3976   Mat_Merge_SeqsToMPI *merge;
3977   PetscContainer      container;
3978 
3979   PetscFunctionBegin;
3980   ierr = PetscObjectGetComm((PetscObject)mpimat,&comm);CHKERRQ(ierr);
3981   ierr = PetscLogEventBegin(MAT_Seqstompinum,seqmat,0,0,0);CHKERRQ(ierr);
3982 
3983   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
3984   ierr = MPI_Comm_rank(comm,&rank);CHKERRQ(ierr);
3985 
3986   ierr = PetscObjectQuery((PetscObject)mpimat,"MatMergeSeqsToMPI",(PetscObject*)&container);CHKERRQ(ierr);
3987   ierr = PetscContainerGetPointer(container,(void**)&merge);CHKERRQ(ierr);
3988 
3989   bi     = merge->bi;
3990   bj     = merge->bj;
3991   buf_ri = merge->buf_ri;
3992   buf_rj = merge->buf_rj;
3993 
3994   ierr   = PetscMalloc1(size,&status);CHKERRQ(ierr);
3995   owners = merge->rowmap->range;
3996   len_s  = merge->len_s;
3997 
3998   /* send and recv matrix values */
3999   /*-----------------------------*/
4000   ierr = PetscObjectGetNewTag((PetscObject)mpimat,&taga);CHKERRQ(ierr);
4001   ierr = PetscPostIrecvScalar(comm,taga,merge->nrecv,merge->id_r,merge->len_r,&abuf_r,&r_waits);CHKERRQ(ierr);
4002 
4003   ierr = PetscMalloc1(merge->nsend+1,&s_waits);CHKERRQ(ierr);
4004   for (proc=0,k=0; proc<size; proc++) {
4005     if (!len_s[proc]) continue;
4006     i    = owners[proc];
4007     ierr = MPI_Isend(aa+ai[i],len_s[proc],MPIU_MATSCALAR,proc,taga,comm,s_waits+k);CHKERRQ(ierr);
4008     k++;
4009   }
4010 
4011   if (merge->nrecv) {ierr = MPI_Waitall(merge->nrecv,r_waits,status);CHKERRQ(ierr);}
4012   if (merge->nsend) {ierr = MPI_Waitall(merge->nsend,s_waits,status);CHKERRQ(ierr);}
4013   ierr = PetscFree(status);CHKERRQ(ierr);
4014 
4015   ierr = PetscFree(s_waits);CHKERRQ(ierr);
4016   ierr = PetscFree(r_waits);CHKERRQ(ierr);
4017 
4018   /* insert mat values of mpimat */
4019   /*----------------------------*/
4020   ierr = PetscMalloc1(N,&ba_i);CHKERRQ(ierr);
4021   ierr = PetscMalloc3(merge->nrecv,&buf_ri_k,merge->nrecv,&nextrow,merge->nrecv,&nextai);CHKERRQ(ierr);
4022 
4023   for (k=0; k<merge->nrecv; k++) {
4024     buf_ri_k[k] = buf_ri[k]; /* beginning of k-th recved i-structure */
4025     nrows       = *(buf_ri_k[k]);
4026     nextrow[k]  = buf_ri_k[k]+1;  /* next row number of k-th recved i-structure */
4027     nextai[k]   = buf_ri_k[k] + (nrows + 1); /* poins to the next i-structure of k-th recved i-structure  */
4028   }
4029 
4030   /* set values of ba */
4031   m = merge->rowmap->n;
4032   for (i=0; i<m; i++) {
4033     arow = owners[rank] + i;
4034     bj_i = bj+bi[i];  /* col indices of the i-th row of mpimat */
4035     bnzi = bi[i+1] - bi[i];
4036     ierr = PetscMemzero(ba_i,bnzi*sizeof(PetscScalar));CHKERRQ(ierr);
4037 
4038     /* add local non-zero vals of this proc's seqmat into ba */
4039     anzi   = ai[arow+1] - ai[arow];
4040     aj     = a->j + ai[arow];
4041     aa     = a->a + ai[arow];
4042     nextaj = 0;
4043     for (j=0; nextaj<anzi; j++) {
4044       if (*(bj_i + j) == aj[nextaj]) { /* bcol == acol */
4045         ba_i[j] += aa[nextaj++];
4046       }
4047     }
4048 
4049     /* add received vals into ba */
4050     for (k=0; k<merge->nrecv; k++) { /* k-th received message */
4051       /* i-th row */
4052       if (i == *nextrow[k]) {
4053         anzi   = *(nextai[k]+1) - *nextai[k];
4054         aj     = buf_rj[k] + *(nextai[k]);
4055         aa     = abuf_r[k] + *(nextai[k]);
4056         nextaj = 0;
4057         for (j=0; nextaj<anzi; j++) {
4058           if (*(bj_i + j) == aj[nextaj]) { /* bcol == acol */
4059             ba_i[j] += aa[nextaj++];
4060           }
4061         }
4062         nextrow[k]++; nextai[k]++;
4063       }
4064     }
4065     ierr = MatSetValues(mpimat,1,&arow,bnzi,bj_i,ba_i,INSERT_VALUES);CHKERRQ(ierr);
4066   }
4067   ierr = MatAssemblyBegin(mpimat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
4068   ierr = MatAssemblyEnd(mpimat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
4069 
4070   ierr = PetscFree(abuf_r[0]);CHKERRQ(ierr);
4071   ierr = PetscFree(abuf_r);CHKERRQ(ierr);
4072   ierr = PetscFree(ba_i);CHKERRQ(ierr);
4073   ierr = PetscFree3(buf_ri_k,nextrow,nextai);CHKERRQ(ierr);
4074   ierr = PetscLogEventEnd(MAT_Seqstompinum,seqmat,0,0,0);CHKERRQ(ierr);
4075   PetscFunctionReturn(0);
4076 }
4077 
4078 extern PetscErrorCode  MatDestroy_MPIAIJ_SeqsToMPI(Mat);
4079 
4080 #undef __FUNCT__
4081 #define __FUNCT__ "MatCreateMPIAIJSumSeqAIJSymbolic"
4082 PetscErrorCode  MatCreateMPIAIJSumSeqAIJSymbolic(MPI_Comm comm,Mat seqmat,PetscInt m,PetscInt n,Mat *mpimat)
4083 {
4084   PetscErrorCode      ierr;
4085   Mat                 B_mpi;
4086   Mat_SeqAIJ          *a=(Mat_SeqAIJ*)seqmat->data;
4087   PetscMPIInt         size,rank,tagi,tagj,*len_s,*len_si,*len_ri;
4088   PetscInt            **buf_rj,**buf_ri,**buf_ri_k;
4089   PetscInt            M=seqmat->rmap->n,N=seqmat->cmap->n,i,*owners,*ai=a->i,*aj=a->j;
4090   PetscInt            len,proc,*dnz,*onz,bs,cbs;
4091   PetscInt            k,anzi,*bi,*bj,*lnk,nlnk,arow,bnzi,nspacedouble=0;
4092   PetscInt            nrows,*buf_s,*buf_si,*buf_si_i,**nextrow,**nextai;
4093   MPI_Request         *si_waits,*sj_waits,*ri_waits,*rj_waits;
4094   MPI_Status          *status;
4095   PetscFreeSpaceList  free_space=NULL,current_space=NULL;
4096   PetscBT             lnkbt;
4097   Mat_Merge_SeqsToMPI *merge;
4098   PetscContainer      container;
4099 
4100   PetscFunctionBegin;
4101   ierr = PetscLogEventBegin(MAT_Seqstompisym,seqmat,0,0,0);CHKERRQ(ierr);
4102 
4103   /* make sure it is a PETSc comm */
4104   ierr = PetscCommDuplicate(comm,&comm,NULL);CHKERRQ(ierr);
4105   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
4106   ierr = MPI_Comm_rank(comm,&rank);CHKERRQ(ierr);
4107 
4108   ierr = PetscNew(&merge);CHKERRQ(ierr);
4109   ierr = PetscMalloc1(size,&status);CHKERRQ(ierr);
4110 
4111   /* determine row ownership */
4112   /*---------------------------------------------------------*/
4113   ierr = PetscLayoutCreate(comm,&merge->rowmap);CHKERRQ(ierr);
4114   ierr = PetscLayoutSetLocalSize(merge->rowmap,m);CHKERRQ(ierr);
4115   ierr = PetscLayoutSetSize(merge->rowmap,M);CHKERRQ(ierr);
4116   ierr = PetscLayoutSetBlockSize(merge->rowmap,1);CHKERRQ(ierr);
4117   ierr = PetscLayoutSetUp(merge->rowmap);CHKERRQ(ierr);
4118   ierr = PetscMalloc1(size,&len_si);CHKERRQ(ierr);
4119   ierr = PetscMalloc1(size,&merge->len_s);CHKERRQ(ierr);
4120 
4121   m      = merge->rowmap->n;
4122   owners = merge->rowmap->range;
4123 
4124   /* determine the number of messages to send, their lengths */
4125   /*---------------------------------------------------------*/
4126   len_s = merge->len_s;
4127 
4128   len          = 0; /* length of buf_si[] */
4129   merge->nsend = 0;
4130   for (proc=0; proc<size; proc++) {
4131     len_si[proc] = 0;
4132     if (proc == rank) {
4133       len_s[proc] = 0;
4134     } else {
4135       len_si[proc] = owners[proc+1] - owners[proc] + 1;
4136       len_s[proc]  = ai[owners[proc+1]] - ai[owners[proc]]; /* num of rows to be sent to [proc] */
4137     }
4138     if (len_s[proc]) {
4139       merge->nsend++;
4140       nrows = 0;
4141       for (i=owners[proc]; i<owners[proc+1]; i++) {
4142         if (ai[i+1] > ai[i]) nrows++;
4143       }
4144       len_si[proc] = 2*(nrows+1);
4145       len         += len_si[proc];
4146     }
4147   }
4148 
4149   /* determine the number and length of messages to receive for ij-structure */
4150   /*-------------------------------------------------------------------------*/
4151   ierr = PetscGatherNumberOfMessages(comm,NULL,len_s,&merge->nrecv);CHKERRQ(ierr);
4152   ierr = PetscGatherMessageLengths2(comm,merge->nsend,merge->nrecv,len_s,len_si,&merge->id_r,&merge->len_r,&len_ri);CHKERRQ(ierr);
4153 
4154   /* post the Irecv of j-structure */
4155   /*-------------------------------*/
4156   ierr = PetscCommGetNewTag(comm,&tagj);CHKERRQ(ierr);
4157   ierr = PetscPostIrecvInt(comm,tagj,merge->nrecv,merge->id_r,merge->len_r,&buf_rj,&rj_waits);CHKERRQ(ierr);
4158 
4159   /* post the Isend of j-structure */
4160   /*--------------------------------*/
4161   ierr = PetscMalloc2(merge->nsend,&si_waits,merge->nsend,&sj_waits);CHKERRQ(ierr);
4162 
4163   for (proc=0, k=0; proc<size; proc++) {
4164     if (!len_s[proc]) continue;
4165     i    = owners[proc];
4166     ierr = MPI_Isend(aj+ai[i],len_s[proc],MPIU_INT,proc,tagj,comm,sj_waits+k);CHKERRQ(ierr);
4167     k++;
4168   }
4169 
4170   /* receives and sends of j-structure are complete */
4171   /*------------------------------------------------*/
4172   if (merge->nrecv) {ierr = MPI_Waitall(merge->nrecv,rj_waits,status);CHKERRQ(ierr);}
4173   if (merge->nsend) {ierr = MPI_Waitall(merge->nsend,sj_waits,status);CHKERRQ(ierr);}
4174 
4175   /* send and recv i-structure */
4176   /*---------------------------*/
4177   ierr = PetscCommGetNewTag(comm,&tagi);CHKERRQ(ierr);
4178   ierr = PetscPostIrecvInt(comm,tagi,merge->nrecv,merge->id_r,len_ri,&buf_ri,&ri_waits);CHKERRQ(ierr);
4179 
4180   ierr   = PetscMalloc1(len+1,&buf_s);CHKERRQ(ierr);
4181   buf_si = buf_s;  /* points to the beginning of k-th msg to be sent */
4182   for (proc=0,k=0; proc<size; proc++) {
4183     if (!len_s[proc]) continue;
4184     /* form outgoing message for i-structure:
4185          buf_si[0]:                 nrows to be sent
4186                [1:nrows]:           row index (global)
4187                [nrows+1:2*nrows+1]: i-structure index
4188     */
4189     /*-------------------------------------------*/
4190     nrows       = len_si[proc]/2 - 1;
4191     buf_si_i    = buf_si + nrows+1;
4192     buf_si[0]   = nrows;
4193     buf_si_i[0] = 0;
4194     nrows       = 0;
4195     for (i=owners[proc]; i<owners[proc+1]; i++) {
4196       anzi = ai[i+1] - ai[i];
4197       if (anzi) {
4198         buf_si_i[nrows+1] = buf_si_i[nrows] + anzi; /* i-structure */
4199         buf_si[nrows+1]   = i-owners[proc]; /* local row index */
4200         nrows++;
4201       }
4202     }
4203     ierr = MPI_Isend(buf_si,len_si[proc],MPIU_INT,proc,tagi,comm,si_waits+k);CHKERRQ(ierr);
4204     k++;
4205     buf_si += len_si[proc];
4206   }
4207 
4208   if (merge->nrecv) {ierr = MPI_Waitall(merge->nrecv,ri_waits,status);CHKERRQ(ierr);}
4209   if (merge->nsend) {ierr = MPI_Waitall(merge->nsend,si_waits,status);CHKERRQ(ierr);}
4210 
4211   ierr = PetscInfo2(seqmat,"nsend: %D, nrecv: %D\n",merge->nsend,merge->nrecv);CHKERRQ(ierr);
4212   for (i=0; i<merge->nrecv; i++) {
4213     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);
4214   }
4215 
4216   ierr = PetscFree(len_si);CHKERRQ(ierr);
4217   ierr = PetscFree(len_ri);CHKERRQ(ierr);
4218   ierr = PetscFree(rj_waits);CHKERRQ(ierr);
4219   ierr = PetscFree2(si_waits,sj_waits);CHKERRQ(ierr);
4220   ierr = PetscFree(ri_waits);CHKERRQ(ierr);
4221   ierr = PetscFree(buf_s);CHKERRQ(ierr);
4222   ierr = PetscFree(status);CHKERRQ(ierr);
4223 
4224   /* compute a local seq matrix in each processor */
4225   /*----------------------------------------------*/
4226   /* allocate bi array and free space for accumulating nonzero column info */
4227   ierr  = PetscMalloc1(m+1,&bi);CHKERRQ(ierr);
4228   bi[0] = 0;
4229 
4230   /* create and initialize a linked list */
4231   nlnk = N+1;
4232   ierr = PetscLLCreate(N,N,nlnk,lnk,lnkbt);CHKERRQ(ierr);
4233 
4234   /* initial FreeSpace size is 2*(num of local nnz(seqmat)) */
4235   len  = ai[owners[rank+1]] - ai[owners[rank]];
4236   ierr = PetscFreeSpaceGet((PetscInt)(2*len+1),&free_space);CHKERRQ(ierr);
4237 
4238   current_space = free_space;
4239 
4240   /* determine symbolic info for each local row */
4241   ierr = PetscMalloc3(merge->nrecv,&buf_ri_k,merge->nrecv,&nextrow,merge->nrecv,&nextai);CHKERRQ(ierr);
4242 
4243   for (k=0; k<merge->nrecv; k++) {
4244     buf_ri_k[k] = buf_ri[k]; /* beginning of k-th recved i-structure */
4245     nrows       = *buf_ri_k[k];
4246     nextrow[k]  = buf_ri_k[k] + 1;  /* next row number of k-th recved i-structure */
4247     nextai[k]   = buf_ri_k[k] + (nrows + 1); /* poins to the next i-structure of k-th recved i-structure  */
4248   }
4249 
4250   ierr = MatPreallocateInitialize(comm,m,n,dnz,onz);CHKERRQ(ierr);
4251   len  = 0;
4252   for (i=0; i<m; i++) {
4253     bnzi = 0;
4254     /* add local non-zero cols of this proc's seqmat into lnk */
4255     arow  = owners[rank] + i;
4256     anzi  = ai[arow+1] - ai[arow];
4257     aj    = a->j + ai[arow];
4258     ierr  = PetscLLAddSorted(anzi,aj,N,nlnk,lnk,lnkbt);CHKERRQ(ierr);
4259     bnzi += nlnk;
4260     /* add received col data into lnk */
4261     for (k=0; k<merge->nrecv; k++) { /* k-th received message */
4262       if (i == *nextrow[k]) { /* i-th row */
4263         anzi  = *(nextai[k]+1) - *nextai[k];
4264         aj    = buf_rj[k] + *nextai[k];
4265         ierr  = PetscLLAddSorted(anzi,aj,N,nlnk,lnk,lnkbt);CHKERRQ(ierr);
4266         bnzi += nlnk;
4267         nextrow[k]++; nextai[k]++;
4268       }
4269     }
4270     if (len < bnzi) len = bnzi;  /* =max(bnzi) */
4271 
4272     /* if free space is not available, make more free space */
4273     if (current_space->local_remaining<bnzi) {
4274       ierr = PetscFreeSpaceGet(bnzi+current_space->total_array_size,&current_space);CHKERRQ(ierr);
4275       nspacedouble++;
4276     }
4277     /* copy data into free space, then initialize lnk */
4278     ierr = PetscLLClean(N,N,bnzi,lnk,current_space->array,lnkbt);CHKERRQ(ierr);
4279     ierr = MatPreallocateSet(i+owners[rank],bnzi,current_space->array,dnz,onz);CHKERRQ(ierr);
4280 
4281     current_space->array           += bnzi;
4282     current_space->local_used      += bnzi;
4283     current_space->local_remaining -= bnzi;
4284 
4285     bi[i+1] = bi[i] + bnzi;
4286   }
4287 
4288   ierr = PetscFree3(buf_ri_k,nextrow,nextai);CHKERRQ(ierr);
4289 
4290   ierr = PetscMalloc1(bi[m]+1,&bj);CHKERRQ(ierr);
4291   ierr = PetscFreeSpaceContiguous(&free_space,bj);CHKERRQ(ierr);
4292   ierr = PetscLLDestroy(lnk,lnkbt);CHKERRQ(ierr);
4293 
4294   /* create symbolic parallel matrix B_mpi */
4295   /*---------------------------------------*/
4296   ierr = MatGetBlockSizes(seqmat,&bs,&cbs);CHKERRQ(ierr);
4297   ierr = MatCreate(comm,&B_mpi);CHKERRQ(ierr);
4298   if (n==PETSC_DECIDE) {
4299     ierr = MatSetSizes(B_mpi,m,n,PETSC_DETERMINE,N);CHKERRQ(ierr);
4300   } else {
4301     ierr = MatSetSizes(B_mpi,m,n,PETSC_DETERMINE,PETSC_DETERMINE);CHKERRQ(ierr);
4302   }
4303   ierr = MatSetBlockSizes(B_mpi,bs,cbs);CHKERRQ(ierr);
4304   ierr = MatSetType(B_mpi,MATMPIAIJ);CHKERRQ(ierr);
4305   ierr = MatMPIAIJSetPreallocation(B_mpi,0,dnz,0,onz);CHKERRQ(ierr);
4306   ierr = MatPreallocateFinalize(dnz,onz);CHKERRQ(ierr);
4307   ierr = MatSetOption(B_mpi,MAT_NEW_NONZERO_ALLOCATION_ERR,PETSC_FALSE);CHKERRQ(ierr);
4308 
4309   /* B_mpi is not ready for use - assembly will be done by MatCreateMPIAIJSumSeqAIJNumeric() */
4310   B_mpi->assembled    = PETSC_FALSE;
4311   B_mpi->ops->destroy = MatDestroy_MPIAIJ_SeqsToMPI;
4312   merge->bi           = bi;
4313   merge->bj           = bj;
4314   merge->buf_ri       = buf_ri;
4315   merge->buf_rj       = buf_rj;
4316   merge->coi          = NULL;
4317   merge->coj          = NULL;
4318   merge->owners_co    = NULL;
4319 
4320   ierr = PetscCommDestroy(&comm);CHKERRQ(ierr);
4321 
4322   /* attach the supporting struct to B_mpi for reuse */
4323   ierr    = PetscContainerCreate(PETSC_COMM_SELF,&container);CHKERRQ(ierr);
4324   ierr    = PetscContainerSetPointer(container,merge);CHKERRQ(ierr);
4325   ierr    = PetscObjectCompose((PetscObject)B_mpi,"MatMergeSeqsToMPI",(PetscObject)container);CHKERRQ(ierr);
4326   ierr    = PetscContainerDestroy(&container);CHKERRQ(ierr);
4327   *mpimat = B_mpi;
4328 
4329   ierr = PetscLogEventEnd(MAT_Seqstompisym,seqmat,0,0,0);CHKERRQ(ierr);
4330   PetscFunctionReturn(0);
4331 }
4332 
4333 #undef __FUNCT__
4334 #define __FUNCT__ "MatCreateMPIAIJSumSeqAIJ"
4335 /*@C
4336       MatCreateMPIAIJSumSeqAIJ - Creates a MPIAIJ matrix by adding sequential
4337                  matrices from each processor
4338 
4339     Collective on MPI_Comm
4340 
4341    Input Parameters:
4342 +    comm - the communicators the parallel matrix will live on
4343 .    seqmat - the input sequential matrices
4344 .    m - number of local rows (or PETSC_DECIDE)
4345 .    n - number of local columns (or PETSC_DECIDE)
4346 -    scall - either MAT_INITIAL_MATRIX or MAT_REUSE_MATRIX
4347 
4348    Output Parameter:
4349 .    mpimat - the parallel matrix generated
4350 
4351     Level: advanced
4352 
4353    Notes:
4354      The dimensions of the sequential matrix in each processor MUST be the same.
4355      The input seqmat is included into the container "Mat_Merge_SeqsToMPI", and will be
4356      destroyed when mpimat is destroyed. Call PetscObjectQuery() to access seqmat.
4357 @*/
4358 PetscErrorCode  MatCreateMPIAIJSumSeqAIJ(MPI_Comm comm,Mat seqmat,PetscInt m,PetscInt n,MatReuse scall,Mat *mpimat)
4359 {
4360   PetscErrorCode ierr;
4361   PetscMPIInt    size;
4362 
4363   PetscFunctionBegin;
4364   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
4365   if (size == 1) {
4366     ierr = PetscLogEventBegin(MAT_Seqstompi,seqmat,0,0,0);CHKERRQ(ierr);
4367     if (scall == MAT_INITIAL_MATRIX) {
4368       ierr = MatDuplicate(seqmat,MAT_COPY_VALUES,mpimat);CHKERRQ(ierr);
4369     } else {
4370       ierr = MatCopy(seqmat,*mpimat,SAME_NONZERO_PATTERN);CHKERRQ(ierr);
4371     }
4372     ierr = PetscLogEventEnd(MAT_Seqstompi,seqmat,0,0,0);CHKERRQ(ierr);
4373     PetscFunctionReturn(0);
4374   }
4375   ierr = PetscLogEventBegin(MAT_Seqstompi,seqmat,0,0,0);CHKERRQ(ierr);
4376   if (scall == MAT_INITIAL_MATRIX) {
4377     ierr = MatCreateMPIAIJSumSeqAIJSymbolic(comm,seqmat,m,n,mpimat);CHKERRQ(ierr);
4378   }
4379   ierr = MatCreateMPIAIJSumSeqAIJNumeric(seqmat,*mpimat);CHKERRQ(ierr);
4380   ierr = PetscLogEventEnd(MAT_Seqstompi,seqmat,0,0,0);CHKERRQ(ierr);
4381   PetscFunctionReturn(0);
4382 }
4383 
4384 #undef __FUNCT__
4385 #define __FUNCT__ "MatMPIAIJGetLocalMat"
4386 /*@
4387      MatMPIAIJGetLocalMat - Creates a SeqAIJ from a MPIAIJ matrix by taking all its local rows and putting them into a sequential vector with
4388           mlocal rows and n columns. Where mlocal is the row count obtained with MatGetLocalSize() and n is the global column count obtained
4389           with MatGetSize()
4390 
4391     Not Collective
4392 
4393    Input Parameters:
4394 +    A - the matrix
4395 .    scall - either MAT_INITIAL_MATRIX or MAT_REUSE_MATRIX
4396 
4397    Output Parameter:
4398 .    A_loc - the local sequential matrix generated
4399 
4400     Level: developer
4401 
4402 .seealso: MatGetOwnerShipRange(), MatMPIAIJGetLocalMatCondensed()
4403 
4404 @*/
4405 PetscErrorCode  MatMPIAIJGetLocalMat(Mat A,MatReuse scall,Mat *A_loc)
4406 {
4407   PetscErrorCode ierr;
4408   Mat_MPIAIJ     *mpimat=(Mat_MPIAIJ*)A->data;
4409   Mat_SeqAIJ     *mat,*a,*b;
4410   PetscInt       *ai,*aj,*bi,*bj,*cmap=mpimat->garray;
4411   MatScalar      *aa,*ba,*cam;
4412   PetscScalar    *ca;
4413   PetscInt       am=A->rmap->n,i,j,k,cstart=A->cmap->rstart;
4414   PetscInt       *ci,*cj,col,ncols_d,ncols_o,jo;
4415   PetscBool      match;
4416   MPI_Comm       comm;
4417   PetscMPIInt    size;
4418 
4419   PetscFunctionBegin;
4420   ierr = PetscObjectTypeCompare((PetscObject)A,MATMPIAIJ,&match);CHKERRQ(ierr);
4421   if (!match) SETERRQ(PetscObjectComm((PetscObject)A), PETSC_ERR_SUP,"Requires MPIAIJ matrix as input");
4422   ierr = PetscObjectGetComm((PetscObject)A,&comm);CHKERRQ(ierr);
4423   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
4424   if (size == 1 && scall == MAT_REUSE_MATRIX) PetscFunctionReturn(0);
4425 
4426   ierr = PetscLogEventBegin(MAT_Getlocalmat,A,0,0,0);CHKERRQ(ierr);
4427   a = (Mat_SeqAIJ*)(mpimat->A)->data;
4428   b = (Mat_SeqAIJ*)(mpimat->B)->data;
4429   ai = a->i; aj = a->j; bi = b->i; bj = b->j;
4430   aa = a->a; ba = b->a;
4431   if (scall == MAT_INITIAL_MATRIX) {
4432     if (size == 1) {
4433       ierr = MatCreateSeqAIJWithArrays(PETSC_COMM_SELF,am,A->cmap->N,ai,aj,aa,A_loc);CHKERRQ(ierr);
4434       PetscFunctionReturn(0);
4435     }
4436 
4437     ierr  = PetscMalloc1(1+am,&ci);CHKERRQ(ierr);
4438     ci[0] = 0;
4439     for (i=0; i<am; i++) {
4440       ci[i+1] = ci[i] + (ai[i+1] - ai[i]) + (bi[i+1] - bi[i]);
4441     }
4442     ierr = PetscMalloc1(1+ci[am],&cj);CHKERRQ(ierr);
4443     ierr = PetscMalloc1(1+ci[am],&ca);CHKERRQ(ierr);
4444     k    = 0;
4445     for (i=0; i<am; i++) {
4446       ncols_o = bi[i+1] - bi[i];
4447       ncols_d = ai[i+1] - ai[i];
4448       /* off-diagonal portion of A */
4449       for (jo=0; jo<ncols_o; jo++) {
4450         col = cmap[*bj];
4451         if (col >= cstart) break;
4452         cj[k]   = col; bj++;
4453         ca[k++] = *ba++;
4454       }
4455       /* diagonal portion of A */
4456       for (j=0; j<ncols_d; j++) {
4457         cj[k]   = cstart + *aj++;
4458         ca[k++] = *aa++;
4459       }
4460       /* off-diagonal portion of A */
4461       for (j=jo; j<ncols_o; j++) {
4462         cj[k]   = cmap[*bj++];
4463         ca[k++] = *ba++;
4464       }
4465     }
4466     /* put together the new matrix */
4467     ierr = MatCreateSeqAIJWithArrays(PETSC_COMM_SELF,am,A->cmap->N,ci,cj,ca,A_loc);CHKERRQ(ierr);
4468     /* MatCreateSeqAIJWithArrays flags matrix so PETSc doesn't free the user's arrays. */
4469     /* Since these are PETSc arrays, change flags to free them as necessary. */
4470     mat          = (Mat_SeqAIJ*)(*A_loc)->data;
4471     mat->free_a  = PETSC_TRUE;
4472     mat->free_ij = PETSC_TRUE;
4473     mat->nonew   = 0;
4474   } else if (scall == MAT_REUSE_MATRIX) {
4475     mat=(Mat_SeqAIJ*)(*A_loc)->data;
4476     ci = mat->i; cj = mat->j; cam = mat->a;
4477     for (i=0; i<am; i++) {
4478       /* off-diagonal portion of A */
4479       ncols_o = bi[i+1] - bi[i];
4480       for (jo=0; jo<ncols_o; jo++) {
4481         col = cmap[*bj];
4482         if (col >= cstart) break;
4483         *cam++ = *ba++; bj++;
4484       }
4485       /* diagonal portion of A */
4486       ncols_d = ai[i+1] - ai[i];
4487       for (j=0; j<ncols_d; j++) *cam++ = *aa++;
4488       /* off-diagonal portion of A */
4489       for (j=jo; j<ncols_o; j++) {
4490         *cam++ = *ba++; bj++;
4491       }
4492     }
4493   } else SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONG,"Invalid MatReuse %d",(int)scall);
4494   ierr = PetscLogEventEnd(MAT_Getlocalmat,A,0,0,0);CHKERRQ(ierr);
4495   PetscFunctionReturn(0);
4496 }
4497 
4498 #undef __FUNCT__
4499 #define __FUNCT__ "MatMPIAIJGetLocalMatCondensed"
4500 /*@C
4501      MatMPIAIJGetLocalMatCondensed - Creates a SeqAIJ matrix from an MPIAIJ matrix by taking all its local rows and NON-ZERO columns
4502 
4503     Not Collective
4504 
4505    Input Parameters:
4506 +    A - the matrix
4507 .    scall - either MAT_INITIAL_MATRIX or MAT_REUSE_MATRIX
4508 -    row, col - index sets of rows and columns to extract (or NULL)
4509 
4510    Output Parameter:
4511 .    A_loc - the local sequential matrix generated
4512 
4513     Level: developer
4514 
4515 .seealso: MatGetOwnershipRange(), MatMPIAIJGetLocalMat()
4516 
4517 @*/
4518 PetscErrorCode  MatMPIAIJGetLocalMatCondensed(Mat A,MatReuse scall,IS *row,IS *col,Mat *A_loc)
4519 {
4520   Mat_MPIAIJ     *a=(Mat_MPIAIJ*)A->data;
4521   PetscErrorCode ierr;
4522   PetscInt       i,start,end,ncols,nzA,nzB,*cmap,imark,*idx;
4523   IS             isrowa,iscola;
4524   Mat            *aloc;
4525   PetscBool      match;
4526 
4527   PetscFunctionBegin;
4528   ierr = PetscObjectTypeCompare((PetscObject)A,MATMPIAIJ,&match);CHKERRQ(ierr);
4529   if (!match) SETERRQ(PetscObjectComm((PetscObject)A), PETSC_ERR_SUP,"Requires MPIAIJ matrix as input");
4530   ierr = PetscLogEventBegin(MAT_Getlocalmatcondensed,A,0,0,0);CHKERRQ(ierr);
4531   if (!row) {
4532     start = A->rmap->rstart; end = A->rmap->rend;
4533     ierr  = ISCreateStride(PETSC_COMM_SELF,end-start,start,1,&isrowa);CHKERRQ(ierr);
4534   } else {
4535     isrowa = *row;
4536   }
4537   if (!col) {
4538     start = A->cmap->rstart;
4539     cmap  = a->garray;
4540     nzA   = a->A->cmap->n;
4541     nzB   = a->B->cmap->n;
4542     ierr  = PetscMalloc1(nzA+nzB, &idx);CHKERRQ(ierr);
4543     ncols = 0;
4544     for (i=0; i<nzB; i++) {
4545       if (cmap[i] < start) idx[ncols++] = cmap[i];
4546       else break;
4547     }
4548     imark = i;
4549     for (i=0; i<nzA; i++) idx[ncols++] = start + i;
4550     for (i=imark; i<nzB; i++) idx[ncols++] = cmap[i];
4551     ierr = ISCreateGeneral(PETSC_COMM_SELF,ncols,idx,PETSC_OWN_POINTER,&iscola);CHKERRQ(ierr);
4552   } else {
4553     iscola = *col;
4554   }
4555   if (scall != MAT_INITIAL_MATRIX) {
4556     ierr    = PetscMalloc1(1,&aloc);CHKERRQ(ierr);
4557     aloc[0] = *A_loc;
4558   }
4559   ierr   = MatGetSubMatrices(A,1,&isrowa,&iscola,scall,&aloc);CHKERRQ(ierr);
4560   *A_loc = aloc[0];
4561   ierr   = PetscFree(aloc);CHKERRQ(ierr);
4562   if (!row) {
4563     ierr = ISDestroy(&isrowa);CHKERRQ(ierr);
4564   }
4565   if (!col) {
4566     ierr = ISDestroy(&iscola);CHKERRQ(ierr);
4567   }
4568   ierr = PetscLogEventEnd(MAT_Getlocalmatcondensed,A,0,0,0);CHKERRQ(ierr);
4569   PetscFunctionReturn(0);
4570 }
4571 
4572 #undef __FUNCT__
4573 #define __FUNCT__ "MatGetBrowsOfAcols"
4574 /*@C
4575     MatGetBrowsOfAcols - Creates a SeqAIJ matrix by taking rows of B that equal to nonzero columns of local A
4576 
4577     Collective on Mat
4578 
4579    Input Parameters:
4580 +    A,B - the matrices in mpiaij format
4581 .    scall - either MAT_INITIAL_MATRIX or MAT_REUSE_MATRIX
4582 -    rowb, colb - index sets of rows and columns of B to extract (or NULL)
4583 
4584    Output Parameter:
4585 +    rowb, colb - index sets of rows and columns of B to extract
4586 -    B_seq - the sequential matrix generated
4587 
4588     Level: developer
4589 
4590 @*/
4591 PetscErrorCode  MatGetBrowsOfAcols(Mat A,Mat B,MatReuse scall,IS *rowb,IS *colb,Mat *B_seq)
4592 {
4593   Mat_MPIAIJ     *a=(Mat_MPIAIJ*)A->data;
4594   PetscErrorCode ierr;
4595   PetscInt       *idx,i,start,ncols,nzA,nzB,*cmap,imark;
4596   IS             isrowb,iscolb;
4597   Mat            *bseq=NULL;
4598 
4599   PetscFunctionBegin;
4600   if (A->cmap->rstart != B->rmap->rstart || A->cmap->rend != B->rmap->rend) {
4601     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);
4602   }
4603   ierr = PetscLogEventBegin(MAT_GetBrowsOfAcols,A,B,0,0);CHKERRQ(ierr);
4604 
4605   if (scall == MAT_INITIAL_MATRIX) {
4606     start = A->cmap->rstart;
4607     cmap  = a->garray;
4608     nzA   = a->A->cmap->n;
4609     nzB   = a->B->cmap->n;
4610     ierr  = PetscMalloc1(nzA+nzB, &idx);CHKERRQ(ierr);
4611     ncols = 0;
4612     for (i=0; i<nzB; i++) {  /* row < local row index */
4613       if (cmap[i] < start) idx[ncols++] = cmap[i];
4614       else break;
4615     }
4616     imark = i;
4617     for (i=0; i<nzA; i++) idx[ncols++] = start + i;  /* local rows */
4618     for (i=imark; i<nzB; i++) idx[ncols++] = cmap[i]; /* row > local row index */
4619     ierr = ISCreateGeneral(PETSC_COMM_SELF,ncols,idx,PETSC_OWN_POINTER,&isrowb);CHKERRQ(ierr);
4620     ierr = ISCreateStride(PETSC_COMM_SELF,B->cmap->N,0,1,&iscolb);CHKERRQ(ierr);
4621   } else {
4622     if (!rowb || !colb) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_SUP,"IS rowb and colb must be provided for MAT_REUSE_MATRIX");
4623     isrowb  = *rowb; iscolb = *colb;
4624     ierr    = PetscMalloc1(1,&bseq);CHKERRQ(ierr);
4625     bseq[0] = *B_seq;
4626   }
4627   ierr   = MatGetSubMatrices(B,1,&isrowb,&iscolb,scall,&bseq);CHKERRQ(ierr);
4628   *B_seq = bseq[0];
4629   ierr   = PetscFree(bseq);CHKERRQ(ierr);
4630   if (!rowb) {
4631     ierr = ISDestroy(&isrowb);CHKERRQ(ierr);
4632   } else {
4633     *rowb = isrowb;
4634   }
4635   if (!colb) {
4636     ierr = ISDestroy(&iscolb);CHKERRQ(ierr);
4637   } else {
4638     *colb = iscolb;
4639   }
4640   ierr = PetscLogEventEnd(MAT_GetBrowsOfAcols,A,B,0,0);CHKERRQ(ierr);
4641   PetscFunctionReturn(0);
4642 }
4643 
4644 #undef __FUNCT__
4645 #define __FUNCT__ "MatGetBrowsOfAoCols_MPIAIJ"
4646 /*
4647     MatGetBrowsOfAoCols_MPIAIJ - Creates a SeqAIJ matrix by taking rows of B that equal to nonzero columns
4648     of the OFF-DIAGONAL portion of local A
4649 
4650     Collective on Mat
4651 
4652    Input Parameters:
4653 +    A,B - the matrices in mpiaij format
4654 -    scall - either MAT_INITIAL_MATRIX or MAT_REUSE_MATRIX
4655 
4656    Output Parameter:
4657 +    startsj_s - starting point in B's sending j-arrays, saved for MAT_REUSE (or NULL)
4658 .    startsj_r - starting point in B's receiving j-arrays, saved for MAT_REUSE (or NULL)
4659 .    bufa_ptr - array for sending matrix values, saved for MAT_REUSE (or NULL)
4660 -    B_oth - the sequential matrix generated with size aBn=a->B->cmap->n by B->cmap->N
4661 
4662     Level: developer
4663 
4664 */
4665 PetscErrorCode  MatGetBrowsOfAoCols_MPIAIJ(Mat A,Mat B,MatReuse scall,PetscInt **startsj_s,PetscInt **startsj_r,MatScalar **bufa_ptr,Mat *B_oth)
4666 {
4667   VecScatter_MPI_General *gen_to,*gen_from;
4668   PetscErrorCode         ierr;
4669   Mat_MPIAIJ             *a=(Mat_MPIAIJ*)A->data;
4670   Mat_SeqAIJ             *b_oth;
4671   VecScatter             ctx =a->Mvctx;
4672   MPI_Comm               comm;
4673   PetscMPIInt            *rprocs,*sprocs,tag=((PetscObject)ctx)->tag,rank;
4674   PetscInt               *rowlen,*bufj,*bufJ,ncols,aBn=a->B->cmap->n,row,*b_othi,*b_othj;
4675   PetscScalar            *rvalues,*svalues;
4676   MatScalar              *b_otha,*bufa,*bufA;
4677   PetscInt               i,j,k,l,ll,nrecvs,nsends,nrows,*srow,*rstarts,*rstartsj = 0,*sstarts,*sstartsj,len;
4678   MPI_Request            *rwaits = NULL,*swaits = NULL;
4679   MPI_Status             *sstatus,rstatus;
4680   PetscMPIInt            jj,size;
4681   PetscInt               *cols,sbs,rbs;
4682   PetscScalar            *vals;
4683 
4684   PetscFunctionBegin;
4685   ierr = PetscObjectGetComm((PetscObject)A,&comm);CHKERRQ(ierr);
4686   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
4687 
4688   if (A->cmap->rstart != B->rmap->rstart || A->cmap->rend != B->rmap->rend) {
4689     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);
4690   }
4691   ierr = PetscLogEventBegin(MAT_GetBrowsOfAocols,A,B,0,0);CHKERRQ(ierr);
4692   ierr = MPI_Comm_rank(comm,&rank);CHKERRQ(ierr);
4693 
4694   gen_to   = (VecScatter_MPI_General*)ctx->todata;
4695   gen_from = (VecScatter_MPI_General*)ctx->fromdata;
4696   rvalues  = gen_from->values; /* holds the length of receiving row */
4697   svalues  = gen_to->values;   /* holds the length of sending row */
4698   nrecvs   = gen_from->n;
4699   nsends   = gen_to->n;
4700 
4701   ierr    = PetscMalloc2(nrecvs,&rwaits,nsends,&swaits);CHKERRQ(ierr);
4702   srow    = gen_to->indices;    /* local row index to be sent */
4703   sstarts = gen_to->starts;
4704   sprocs  = gen_to->procs;
4705   sstatus = gen_to->sstatus;
4706   sbs     = gen_to->bs;
4707   rstarts = gen_from->starts;
4708   rprocs  = gen_from->procs;
4709   rbs     = gen_from->bs;
4710 
4711   if (!startsj_s || !bufa_ptr) scall = MAT_INITIAL_MATRIX;
4712   if (scall == MAT_INITIAL_MATRIX) {
4713     /* i-array */
4714     /*---------*/
4715     /*  post receives */
4716     for (i=0; i<nrecvs; i++) {
4717       rowlen = (PetscInt*)rvalues + rstarts[i]*rbs;
4718       nrows  = (rstarts[i+1]-rstarts[i])*rbs; /* num of indices to be received */
4719       ierr   = MPI_Irecv(rowlen,nrows,MPIU_INT,rprocs[i],tag,comm,rwaits+i);CHKERRQ(ierr);
4720     }
4721 
4722     /* pack the outgoing message */
4723     ierr = PetscMalloc2(nsends+1,&sstartsj,nrecvs+1,&rstartsj);CHKERRQ(ierr);
4724 
4725     sstartsj[0] = 0;
4726     rstartsj[0] = 0;
4727     len         = 0; /* total length of j or a array to be sent */
4728     k           = 0;
4729     for (i=0; i<nsends; i++) {
4730       rowlen = (PetscInt*)svalues + sstarts[i]*sbs;
4731       nrows  = sstarts[i+1]-sstarts[i]; /* num of block rows */
4732       for (j=0; j<nrows; j++) {
4733         row = srow[k] + B->rmap->range[rank]; /* global row idx */
4734         for (l=0; l<sbs; l++) {
4735           ierr = MatGetRow_MPIAIJ(B,row+l,&ncols,NULL,NULL);CHKERRQ(ierr); /* rowlength */
4736 
4737           rowlen[j*sbs+l] = ncols;
4738 
4739           len += ncols;
4740           ierr = MatRestoreRow_MPIAIJ(B,row+l,&ncols,NULL,NULL);CHKERRQ(ierr);
4741         }
4742         k++;
4743       }
4744       ierr = MPI_Isend(rowlen,nrows*sbs,MPIU_INT,sprocs[i],tag,comm,swaits+i);CHKERRQ(ierr);
4745 
4746       sstartsj[i+1] = len;  /* starting point of (i+1)-th outgoing msg in bufj and bufa */
4747     }
4748     /* recvs and sends of i-array are completed */
4749     i = nrecvs;
4750     while (i--) {
4751       ierr = MPI_Waitany(nrecvs,rwaits,&jj,&rstatus);CHKERRQ(ierr);
4752     }
4753     if (nsends) {ierr = MPI_Waitall(nsends,swaits,sstatus);CHKERRQ(ierr);}
4754 
4755     /* allocate buffers for sending j and a arrays */
4756     ierr = PetscMalloc1(len+1,&bufj);CHKERRQ(ierr);
4757     ierr = PetscMalloc1(len+1,&bufa);CHKERRQ(ierr);
4758 
4759     /* create i-array of B_oth */
4760     ierr = PetscMalloc1(aBn+2,&b_othi);CHKERRQ(ierr);
4761 
4762     b_othi[0] = 0;
4763     len       = 0; /* total length of j or a array to be received */
4764     k         = 0;
4765     for (i=0; i<nrecvs; i++) {
4766       rowlen = (PetscInt*)rvalues + rstarts[i]*rbs;
4767       nrows  = rbs*(rstarts[i+1]-rstarts[i]); /* num of rows to be recieved */
4768       for (j=0; j<nrows; j++) {
4769         b_othi[k+1] = b_othi[k] + rowlen[j];
4770         len        += rowlen[j]; k++;
4771       }
4772       rstartsj[i+1] = len; /* starting point of (i+1)-th incoming msg in bufj and bufa */
4773     }
4774 
4775     /* allocate space for j and a arrrays of B_oth */
4776     ierr = PetscMalloc1(b_othi[aBn]+1,&b_othj);CHKERRQ(ierr);
4777     ierr = PetscMalloc1(b_othi[aBn]+1,&b_otha);CHKERRQ(ierr);
4778 
4779     /* j-array */
4780     /*---------*/
4781     /*  post receives of j-array */
4782     for (i=0; i<nrecvs; i++) {
4783       nrows = rstartsj[i+1]-rstartsj[i]; /* length of the msg received */
4784       ierr  = MPI_Irecv(b_othj+rstartsj[i],nrows,MPIU_INT,rprocs[i],tag,comm,rwaits+i);CHKERRQ(ierr);
4785     }
4786 
4787     /* pack the outgoing message j-array */
4788     k = 0;
4789     for (i=0; i<nsends; i++) {
4790       nrows = sstarts[i+1]-sstarts[i]; /* num of block rows */
4791       bufJ  = bufj+sstartsj[i];
4792       for (j=0; j<nrows; j++) {
4793         row = srow[k++] + B->rmap->range[rank];  /* global row idx */
4794         for (ll=0; ll<sbs; ll++) {
4795           ierr = MatGetRow_MPIAIJ(B,row+ll,&ncols,&cols,NULL);CHKERRQ(ierr);
4796           for (l=0; l<ncols; l++) {
4797             *bufJ++ = cols[l];
4798           }
4799           ierr = MatRestoreRow_MPIAIJ(B,row+ll,&ncols,&cols,NULL);CHKERRQ(ierr);
4800         }
4801       }
4802       ierr = MPI_Isend(bufj+sstartsj[i],sstartsj[i+1]-sstartsj[i],MPIU_INT,sprocs[i],tag,comm,swaits+i);CHKERRQ(ierr);
4803     }
4804 
4805     /* recvs and sends of j-array are completed */
4806     i = nrecvs;
4807     while (i--) {
4808       ierr = MPI_Waitany(nrecvs,rwaits,&jj,&rstatus);CHKERRQ(ierr);
4809     }
4810     if (nsends) {ierr = MPI_Waitall(nsends,swaits,sstatus);CHKERRQ(ierr);}
4811   } else if (scall == MAT_REUSE_MATRIX) {
4812     sstartsj = *startsj_s;
4813     rstartsj = *startsj_r;
4814     bufa     = *bufa_ptr;
4815     b_oth    = (Mat_SeqAIJ*)(*B_oth)->data;
4816     b_otha   = b_oth->a;
4817   } else SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE, "Matrix P does not posses an object container");
4818 
4819   /* a-array */
4820   /*---------*/
4821   /*  post receives of a-array */
4822   for (i=0; i<nrecvs; i++) {
4823     nrows = rstartsj[i+1]-rstartsj[i]; /* length of the msg received */
4824     ierr  = MPI_Irecv(b_otha+rstartsj[i],nrows,MPIU_SCALAR,rprocs[i],tag,comm,rwaits+i);CHKERRQ(ierr);
4825   }
4826 
4827   /* pack the outgoing message a-array */
4828   k = 0;
4829   for (i=0; i<nsends; i++) {
4830     nrows = sstarts[i+1]-sstarts[i]; /* num of block rows */
4831     bufA  = bufa+sstartsj[i];
4832     for (j=0; j<nrows; j++) {
4833       row = srow[k++] + B->rmap->range[rank];  /* global row idx */
4834       for (ll=0; ll<sbs; ll++) {
4835         ierr = MatGetRow_MPIAIJ(B,row+ll,&ncols,NULL,&vals);CHKERRQ(ierr);
4836         for (l=0; l<ncols; l++) {
4837           *bufA++ = vals[l];
4838         }
4839         ierr = MatRestoreRow_MPIAIJ(B,row+ll,&ncols,NULL,&vals);CHKERRQ(ierr);
4840       }
4841     }
4842     ierr = MPI_Isend(bufa+sstartsj[i],sstartsj[i+1]-sstartsj[i],MPIU_SCALAR,sprocs[i],tag,comm,swaits+i);CHKERRQ(ierr);
4843   }
4844   /* recvs and sends of a-array are completed */
4845   i = nrecvs;
4846   while (i--) {
4847     ierr = MPI_Waitany(nrecvs,rwaits,&jj,&rstatus);CHKERRQ(ierr);
4848   }
4849   if (nsends) {ierr = MPI_Waitall(nsends,swaits,sstatus);CHKERRQ(ierr);}
4850   ierr = PetscFree2(rwaits,swaits);CHKERRQ(ierr);
4851 
4852   if (scall == MAT_INITIAL_MATRIX) {
4853     /* put together the new matrix */
4854     ierr = MatCreateSeqAIJWithArrays(PETSC_COMM_SELF,aBn,B->cmap->N,b_othi,b_othj,b_otha,B_oth);CHKERRQ(ierr);
4855 
4856     /* MatCreateSeqAIJWithArrays flags matrix so PETSc doesn't free the user's arrays. */
4857     /* Since these are PETSc arrays, change flags to free them as necessary. */
4858     b_oth          = (Mat_SeqAIJ*)(*B_oth)->data;
4859     b_oth->free_a  = PETSC_TRUE;
4860     b_oth->free_ij = PETSC_TRUE;
4861     b_oth->nonew   = 0;
4862 
4863     ierr = PetscFree(bufj);CHKERRQ(ierr);
4864     if (!startsj_s || !bufa_ptr) {
4865       ierr = PetscFree2(sstartsj,rstartsj);CHKERRQ(ierr);
4866       ierr = PetscFree(bufa_ptr);CHKERRQ(ierr);
4867     } else {
4868       *startsj_s = sstartsj;
4869       *startsj_r = rstartsj;
4870       *bufa_ptr  = bufa;
4871     }
4872   }
4873   ierr = PetscLogEventEnd(MAT_GetBrowsOfAocols,A,B,0,0);CHKERRQ(ierr);
4874   PetscFunctionReturn(0);
4875 }
4876 
4877 #undef __FUNCT__
4878 #define __FUNCT__ "MatGetCommunicationStructs"
4879 /*@C
4880   MatGetCommunicationStructs - Provides access to the communication structures used in matrix-vector multiplication.
4881 
4882   Not Collective
4883 
4884   Input Parameters:
4885 . A - The matrix in mpiaij format
4886 
4887   Output Parameter:
4888 + lvec - The local vector holding off-process values from the argument to a matrix-vector product
4889 . colmap - A map from global column index to local index into lvec
4890 - multScatter - A scatter from the argument of a matrix-vector product to lvec
4891 
4892   Level: developer
4893 
4894 @*/
4895 #if defined(PETSC_USE_CTABLE)
4896 PetscErrorCode  MatGetCommunicationStructs(Mat A, Vec *lvec, PetscTable *colmap, VecScatter *multScatter)
4897 #else
4898 PetscErrorCode  MatGetCommunicationStructs(Mat A, Vec *lvec, PetscInt *colmap[], VecScatter *multScatter)
4899 #endif
4900 {
4901   Mat_MPIAIJ *a;
4902 
4903   PetscFunctionBegin;
4904   PetscValidHeaderSpecific(A, MAT_CLASSID, 1);
4905   PetscValidPointer(lvec, 2);
4906   PetscValidPointer(colmap, 3);
4907   PetscValidPointer(multScatter, 4);
4908   a = (Mat_MPIAIJ*) A->data;
4909   if (lvec) *lvec = a->lvec;
4910   if (colmap) *colmap = a->colmap;
4911   if (multScatter) *multScatter = a->Mvctx;
4912   PetscFunctionReturn(0);
4913 }
4914 
4915 PETSC_EXTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJCRL(Mat,MatType,MatReuse,Mat*);
4916 PETSC_EXTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJPERM(Mat,MatType,MatReuse,Mat*);
4917 PETSC_EXTERN PetscErrorCode MatConvert_MPIAIJ_MPISBAIJ(Mat,MatType,MatReuse,Mat*);
4918 #if defined(PETSC_HAVE_ELEMENTAL)
4919 PETSC_EXTERN PetscErrorCode MatConvert_MPIAIJ_Elemental(Mat,MatType,MatReuse,Mat*);
4920 #endif
4921 
4922 #undef __FUNCT__
4923 #define __FUNCT__ "MatMatMultNumeric_MPIDense_MPIAIJ"
4924 /*
4925     Computes (B'*A')' since computing B*A directly is untenable
4926 
4927                n                       p                          p
4928         (              )       (              )         (                  )
4929       m (      A       )  *  n (       B      )   =   m (         C        )
4930         (              )       (              )         (                  )
4931 
4932 */
4933 PetscErrorCode MatMatMultNumeric_MPIDense_MPIAIJ(Mat A,Mat B,Mat C)
4934 {
4935   PetscErrorCode ierr;
4936   Mat            At,Bt,Ct;
4937 
4938   PetscFunctionBegin;
4939   ierr = MatTranspose(A,MAT_INITIAL_MATRIX,&At);CHKERRQ(ierr);
4940   ierr = MatTranspose(B,MAT_INITIAL_MATRIX,&Bt);CHKERRQ(ierr);
4941   ierr = MatMatMult(Bt,At,MAT_INITIAL_MATRIX,1.0,&Ct);CHKERRQ(ierr);
4942   ierr = MatDestroy(&At);CHKERRQ(ierr);
4943   ierr = MatDestroy(&Bt);CHKERRQ(ierr);
4944   ierr = MatTranspose(Ct,MAT_REUSE_MATRIX,&C);CHKERRQ(ierr);
4945   ierr = MatDestroy(&Ct);CHKERRQ(ierr);
4946   PetscFunctionReturn(0);
4947 }
4948 
4949 #undef __FUNCT__
4950 #define __FUNCT__ "MatMatMultSymbolic_MPIDense_MPIAIJ"
4951 PetscErrorCode MatMatMultSymbolic_MPIDense_MPIAIJ(Mat A,Mat B,PetscReal fill,Mat *C)
4952 {
4953   PetscErrorCode ierr;
4954   PetscInt       m=A->rmap->n,n=B->cmap->n;
4955   Mat            Cmat;
4956 
4957   PetscFunctionBegin;
4958   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);
4959   ierr = MatCreate(PetscObjectComm((PetscObject)A),&Cmat);CHKERRQ(ierr);
4960   ierr = MatSetSizes(Cmat,m,n,PETSC_DETERMINE,PETSC_DETERMINE);CHKERRQ(ierr);
4961   ierr = MatSetBlockSizesFromMats(Cmat,A,B);CHKERRQ(ierr);
4962   ierr = MatSetType(Cmat,MATMPIDENSE);CHKERRQ(ierr);
4963   ierr = MatMPIDenseSetPreallocation(Cmat,NULL);CHKERRQ(ierr);
4964   ierr = MatAssemblyBegin(Cmat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
4965   ierr = MatAssemblyEnd(Cmat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
4966 
4967   Cmat->ops->matmultnumeric = MatMatMultNumeric_MPIDense_MPIAIJ;
4968 
4969   *C = Cmat;
4970   PetscFunctionReturn(0);
4971 }
4972 
4973 /* ----------------------------------------------------------------*/
4974 #undef __FUNCT__
4975 #define __FUNCT__ "MatMatMult_MPIDense_MPIAIJ"
4976 PetscErrorCode MatMatMult_MPIDense_MPIAIJ(Mat A,Mat B,MatReuse scall,PetscReal fill,Mat *C)
4977 {
4978   PetscErrorCode ierr;
4979 
4980   PetscFunctionBegin;
4981   if (scall == MAT_INITIAL_MATRIX) {
4982     ierr = PetscLogEventBegin(MAT_MatMultSymbolic,A,B,0,0);CHKERRQ(ierr);
4983     ierr = MatMatMultSymbolic_MPIDense_MPIAIJ(A,B,fill,C);CHKERRQ(ierr);
4984     ierr = PetscLogEventEnd(MAT_MatMultSymbolic,A,B,0,0);CHKERRQ(ierr);
4985   }
4986   ierr = PetscLogEventBegin(MAT_MatMultNumeric,A,B,0,0);CHKERRQ(ierr);
4987   ierr = MatMatMultNumeric_MPIDense_MPIAIJ(A,B,*C);CHKERRQ(ierr);
4988   ierr = PetscLogEventEnd(MAT_MatMultNumeric,A,B,0,0);CHKERRQ(ierr);
4989   PetscFunctionReturn(0);
4990 }
4991 
4992 /*MC
4993    MATMPIAIJ - MATMPIAIJ = "mpiaij" - A matrix type to be used for parallel sparse matrices.
4994 
4995    Options Database Keys:
4996 . -mat_type mpiaij - sets the matrix type to "mpiaij" during a call to MatSetFromOptions()
4997 
4998   Level: beginner
4999 
5000 .seealso: MatCreateAIJ()
5001 M*/
5002 
5003 #undef __FUNCT__
5004 #define __FUNCT__ "MatCreate_MPIAIJ"
5005 PETSC_EXTERN PetscErrorCode MatCreate_MPIAIJ(Mat B)
5006 {
5007   Mat_MPIAIJ     *b;
5008   PetscErrorCode ierr;
5009   PetscMPIInt    size;
5010 
5011   PetscFunctionBegin;
5012   ierr = MPI_Comm_size(PetscObjectComm((PetscObject)B),&size);CHKERRQ(ierr);
5013 
5014   ierr          = PetscNewLog(B,&b);CHKERRQ(ierr);
5015   B->data       = (void*)b;
5016   ierr          = PetscMemcpy(B->ops,&MatOps_Values,sizeof(struct _MatOps));CHKERRQ(ierr);
5017   B->assembled  = PETSC_FALSE;
5018   B->insertmode = NOT_SET_VALUES;
5019   b->size       = size;
5020 
5021   ierr = MPI_Comm_rank(PetscObjectComm((PetscObject)B),&b->rank);CHKERRQ(ierr);
5022 
5023   /* build cache for off array entries formed */
5024   ierr = MatStashCreate_Private(PetscObjectComm((PetscObject)B),1,&B->stash);CHKERRQ(ierr);
5025 
5026   b->donotstash  = PETSC_FALSE;
5027   b->colmap      = 0;
5028   b->garray      = 0;
5029   b->roworiented = PETSC_TRUE;
5030 
5031   /* stuff used for matrix vector multiply */
5032   b->lvec  = NULL;
5033   b->Mvctx = NULL;
5034 
5035   /* stuff for MatGetRow() */
5036   b->rowindices   = 0;
5037   b->rowvalues    = 0;
5038   b->getrowactive = PETSC_FALSE;
5039 
5040   /* flexible pointer used in CUSP/CUSPARSE classes */
5041   b->spptr = NULL;
5042 
5043   ierr = PetscObjectComposeFunction((PetscObject)B,"MatMPIAIJSetUseScalableIncreaseOverlap_C",MatMPIAIJSetUseScalableIncreaseOverlap_MPIAIJ);CHKERRQ(ierr);
5044   ierr = PetscObjectComposeFunction((PetscObject)B,"MatStoreValues_C",MatStoreValues_MPIAIJ);CHKERRQ(ierr);
5045   ierr = PetscObjectComposeFunction((PetscObject)B,"MatRetrieveValues_C",MatRetrieveValues_MPIAIJ);CHKERRQ(ierr);
5046   ierr = PetscObjectComposeFunction((PetscObject)B,"MatGetDiagonalBlock_C",MatGetDiagonalBlock_MPIAIJ);CHKERRQ(ierr);
5047   ierr = PetscObjectComposeFunction((PetscObject)B,"MatIsTranspose_C",MatIsTranspose_MPIAIJ);CHKERRQ(ierr);
5048   ierr = PetscObjectComposeFunction((PetscObject)B,"MatMPIAIJSetPreallocation_C",MatMPIAIJSetPreallocation_MPIAIJ);CHKERRQ(ierr);
5049   ierr = PetscObjectComposeFunction((PetscObject)B,"MatMPIAIJSetPreallocationCSR_C",MatMPIAIJSetPreallocationCSR_MPIAIJ);CHKERRQ(ierr);
5050   ierr = PetscObjectComposeFunction((PetscObject)B,"MatDiagonalScaleLocal_C",MatDiagonalScaleLocal_MPIAIJ);CHKERRQ(ierr);
5051   ierr = PetscObjectComposeFunction((PetscObject)B,"MatConvert_mpiaij_mpiaijperm_C",MatConvert_MPIAIJ_MPIAIJPERM);CHKERRQ(ierr);
5052   ierr = PetscObjectComposeFunction((PetscObject)B,"MatConvert_mpiaij_mpiaijcrl_C",MatConvert_MPIAIJ_MPIAIJCRL);CHKERRQ(ierr);
5053   ierr = PetscObjectComposeFunction((PetscObject)B,"MatConvert_mpiaij_mpisbaij_C",MatConvert_MPIAIJ_MPISBAIJ);CHKERRQ(ierr);
5054 #if defined(PETSC_HAVE_ELEMENTAL)
5055   ierr = PetscObjectComposeFunction((PetscObject)B,"MatConvert_mpiaij_elemental_C",MatConvert_MPIAIJ_Elemental);CHKERRQ(ierr);
5056 #endif
5057   ierr = PetscObjectComposeFunction((PetscObject)B,"MatMatMult_mpidense_mpiaij_C",MatMatMult_MPIDense_MPIAIJ);CHKERRQ(ierr);
5058   ierr = PetscObjectComposeFunction((PetscObject)B,"MatMatMultSymbolic_mpidense_mpiaij_C",MatMatMultSymbolic_MPIDense_MPIAIJ);CHKERRQ(ierr);
5059   ierr = PetscObjectComposeFunction((PetscObject)B,"MatMatMultNumeric_mpidense_mpiaij_C",MatMatMultNumeric_MPIDense_MPIAIJ);CHKERRQ(ierr);
5060   ierr = PetscObjectChangeTypeName((PetscObject)B,MATMPIAIJ);CHKERRQ(ierr);
5061   PetscFunctionReturn(0);
5062 }
5063 
5064 #undef __FUNCT__
5065 #define __FUNCT__ "MatCreateMPIAIJWithSplitArrays"
5066 /*@C
5067      MatCreateMPIAIJWithSplitArrays - creates a MPI AIJ matrix using arrays that contain the "diagonal"
5068          and "off-diagonal" part of the matrix in CSR format.
5069 
5070    Collective on MPI_Comm
5071 
5072    Input Parameters:
5073 +  comm - MPI communicator
5074 .  m - number of local rows (Cannot be PETSC_DECIDE)
5075 .  n - This value should be the same as the local size used in creating the
5076        x vector for the matrix-vector product y = Ax. (or PETSC_DECIDE to have
5077        calculated if N is given) For square matrices n is almost always m.
5078 .  M - number of global rows (or PETSC_DETERMINE to have calculated if m is given)
5079 .  N - number of global columns (or PETSC_DETERMINE to have calculated if n is given)
5080 .   i - row indices for "diagonal" portion of matrix
5081 .   j - column indices
5082 .   a - matrix values
5083 .   oi - row indices for "off-diagonal" portion of matrix
5084 .   oj - column indices
5085 -   oa - matrix values
5086 
5087    Output Parameter:
5088 .   mat - the matrix
5089 
5090    Level: advanced
5091 
5092    Notes:
5093        The i, j, and a arrays ARE NOT copied by this routine into the internal format used by PETSc. The user
5094        must free the arrays once the matrix has been destroyed and not before.
5095 
5096        The i and j indices are 0 based
5097 
5098        See MatCreateAIJ() for the definition of "diagonal" and "off-diagonal" portion of the matrix
5099 
5100        This sets local rows and cannot be used to set off-processor values.
5101 
5102        Use of this routine is discouraged because it is inflexible and cumbersome to use. It is extremely rare that a
5103        legacy application natively assembles into exactly this split format. The code to do so is nontrivial and does
5104        not easily support in-place reassembly. It is recommended to use MatSetValues() (or a variant thereof) because
5105        the resulting assembly is easier to implement, will work with any matrix format, and the user does not have to
5106        keep track of the underlying array. Use MatSetOption(A,MAT_IGNORE_OFF_PROC_ENTRIES,PETSC_TRUE) to disable all
5107        communication if it is known that only local entries will be set.
5108 
5109 .keywords: matrix, aij, compressed row, sparse, parallel
5110 
5111 .seealso: MatCreate(), MatCreateSeqAIJ(), MatSetValues(), MatMPIAIJSetPreallocation(), MatMPIAIJSetPreallocationCSR(),
5112           MPIAIJ, MatCreateAIJ(), MatCreateMPIAIJWithArrays()
5113 @*/
5114 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)
5115 {
5116   PetscErrorCode ierr;
5117   Mat_MPIAIJ     *maij;
5118 
5119   PetscFunctionBegin;
5120   if (m < 0) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"local number of rows (m) cannot be PETSC_DECIDE, or negative");
5121   if (i[0]) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"i (row indices) must start with 0");
5122   if (oi[0]) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"oi (row indices) must start with 0");
5123   ierr = MatCreate(comm,mat);CHKERRQ(ierr);
5124   ierr = MatSetSizes(*mat,m,n,M,N);CHKERRQ(ierr);
5125   ierr = MatSetType(*mat,MATMPIAIJ);CHKERRQ(ierr);
5126   maij = (Mat_MPIAIJ*) (*mat)->data;
5127 
5128   (*mat)->preallocated = PETSC_TRUE;
5129 
5130   ierr = PetscLayoutSetUp((*mat)->rmap);CHKERRQ(ierr);
5131   ierr = PetscLayoutSetUp((*mat)->cmap);CHKERRQ(ierr);
5132 
5133   ierr = MatCreateSeqAIJWithArrays(PETSC_COMM_SELF,m,n,i,j,a,&maij->A);CHKERRQ(ierr);
5134   ierr = MatCreateSeqAIJWithArrays(PETSC_COMM_SELF,m,(*mat)->cmap->N,oi,oj,oa,&maij->B);CHKERRQ(ierr);
5135 
5136   ierr = MatAssemblyBegin(maij->A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
5137   ierr = MatAssemblyEnd(maij->A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
5138   ierr = MatAssemblyBegin(maij->B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
5139   ierr = MatAssemblyEnd(maij->B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
5140 
5141   ierr = MatAssemblyBegin(*mat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
5142   ierr = MatAssemblyEnd(*mat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
5143   ierr = MatSetOption(*mat,MAT_NEW_NONZERO_LOCATION_ERR,PETSC_TRUE);CHKERRQ(ierr);
5144   PetscFunctionReturn(0);
5145 }
5146 
5147 /*
5148     Special version for direct calls from Fortran
5149 */
5150 #include <petsc/private/fortranimpl.h>
5151 
5152 #if defined(PETSC_HAVE_FORTRAN_CAPS)
5153 #define matsetvaluesmpiaij_ MATSETVALUESMPIAIJ
5154 #elif !defined(PETSC_HAVE_FORTRAN_UNDERSCORE)
5155 #define matsetvaluesmpiaij_ matsetvaluesmpiaij
5156 #endif
5157 
5158 /* Change these macros so can be used in void function */
5159 #undef CHKERRQ
5160 #define CHKERRQ(ierr) CHKERRABORT(PETSC_COMM_WORLD,ierr)
5161 #undef SETERRQ2
5162 #define SETERRQ2(comm,ierr,b,c,d) CHKERRABORT(comm,ierr)
5163 #undef SETERRQ3
5164 #define SETERRQ3(comm,ierr,b,c,d,e) CHKERRABORT(comm,ierr)
5165 #undef SETERRQ
5166 #define SETERRQ(c,ierr,b) CHKERRABORT(c,ierr)
5167 
5168 #undef __FUNCT__
5169 #define __FUNCT__ "matsetvaluesmpiaij_"
5170 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)
5171 {
5172   Mat            mat  = *mmat;
5173   PetscInt       m    = *mm, n = *mn;
5174   InsertMode     addv = *maddv;
5175   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
5176   PetscScalar    value;
5177   PetscErrorCode ierr;
5178 
5179   MatCheckPreallocated(mat,1);
5180   if (mat->insertmode == NOT_SET_VALUES) mat->insertmode = addv;
5181 
5182 #if defined(PETSC_USE_DEBUG)
5183   else if (mat->insertmode != addv) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"Cannot mix add values and insert values");
5184 #endif
5185   {
5186     PetscInt  i,j,rstart  = mat->rmap->rstart,rend = mat->rmap->rend;
5187     PetscInt  cstart      = mat->cmap->rstart,cend = mat->cmap->rend,row,col;
5188     PetscBool roworiented = aij->roworiented;
5189 
5190     /* Some Variables required in the macro */
5191     Mat        A                 = aij->A;
5192     Mat_SeqAIJ *a                = (Mat_SeqAIJ*)A->data;
5193     PetscInt   *aimax            = a->imax,*ai = a->i,*ailen = a->ilen,*aj = a->j;
5194     MatScalar  *aa               = a->a;
5195     PetscBool  ignorezeroentries = (((a->ignorezeroentries)&&(addv==ADD_VALUES)) ? PETSC_TRUE : PETSC_FALSE);
5196     Mat        B                 = aij->B;
5197     Mat_SeqAIJ *b                = (Mat_SeqAIJ*)B->data;
5198     PetscInt   *bimax            = b->imax,*bi = b->i,*bilen = b->ilen,*bj = b->j,bm = aij->B->rmap->n,am = aij->A->rmap->n;
5199     MatScalar  *ba               = b->a;
5200 
5201     PetscInt  *rp1,*rp2,ii,nrow1,nrow2,_i,rmax1,rmax2,N,low1,high1,low2,high2,t,lastcol1,lastcol2;
5202     PetscInt  nonew = a->nonew;
5203     MatScalar *ap1,*ap2;
5204 
5205     PetscFunctionBegin;
5206     for (i=0; i<m; i++) {
5207       if (im[i] < 0) continue;
5208 #if defined(PETSC_USE_DEBUG)
5209       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);
5210 #endif
5211       if (im[i] >= rstart && im[i] < rend) {
5212         row      = im[i] - rstart;
5213         lastcol1 = -1;
5214         rp1      = aj + ai[row];
5215         ap1      = aa + ai[row];
5216         rmax1    = aimax[row];
5217         nrow1    = ailen[row];
5218         low1     = 0;
5219         high1    = nrow1;
5220         lastcol2 = -1;
5221         rp2      = bj + bi[row];
5222         ap2      = ba + bi[row];
5223         rmax2    = bimax[row];
5224         nrow2    = bilen[row];
5225         low2     = 0;
5226         high2    = nrow2;
5227 
5228         for (j=0; j<n; j++) {
5229           if (roworiented) value = v[i*n+j];
5230           else value = v[i+j*m];
5231           if (ignorezeroentries && value == 0.0 && (addv == ADD_VALUES)) continue;
5232           if (in[j] >= cstart && in[j] < cend) {
5233             col = in[j] - cstart;
5234             MatSetValues_SeqAIJ_A_Private(row,col,value,addv,im[i],in[j]);
5235           } else if (in[j] < 0) continue;
5236 #if defined(PETSC_USE_DEBUG)
5237           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);
5238 #endif
5239           else {
5240             if (mat->was_assembled) {
5241               if (!aij->colmap) {
5242                 ierr = MatCreateColmap_MPIAIJ_Private(mat);CHKERRQ(ierr);
5243               }
5244 #if defined(PETSC_USE_CTABLE)
5245               ierr = PetscTableFind(aij->colmap,in[j]+1,&col);CHKERRQ(ierr);
5246               col--;
5247 #else
5248               col = aij->colmap[in[j]] - 1;
5249 #endif
5250               if (col < 0 && !((Mat_SeqAIJ*)(aij->A->data))->nonew) {
5251                 ierr = MatDisAssemble_MPIAIJ(mat);CHKERRQ(ierr);
5252                 col  =  in[j];
5253                 /* Reinitialize the variables required by MatSetValues_SeqAIJ_B_Private() */
5254                 B     = aij->B;
5255                 b     = (Mat_SeqAIJ*)B->data;
5256                 bimax = b->imax; bi = b->i; bilen = b->ilen; bj = b->j;
5257                 rp2   = bj + bi[row];
5258                 ap2   = ba + bi[row];
5259                 rmax2 = bimax[row];
5260                 nrow2 = bilen[row];
5261                 low2  = 0;
5262                 high2 = nrow2;
5263                 bm    = aij->B->rmap->n;
5264                 ba    = b->a;
5265               }
5266             } else col = in[j];
5267             MatSetValues_SeqAIJ_B_Private(row,col,value,addv,im[i],in[j]);
5268           }
5269         }
5270       } else if (!aij->donotstash) {
5271         if (roworiented) {
5272           ierr = MatStashValuesRow_Private(&mat->stash,im[i],n,in,v+i*n,(PetscBool)(ignorezeroentries && (addv == ADD_VALUES)));CHKERRQ(ierr);
5273         } else {
5274           ierr = MatStashValuesCol_Private(&mat->stash,im[i],n,in,v+i,m,(PetscBool)(ignorezeroentries && (addv == ADD_VALUES)));CHKERRQ(ierr);
5275         }
5276       }
5277     }
5278   }
5279   PetscFunctionReturnVoid();
5280 }
5281 
5282