xref: /petsc/src/mat/impls/aij/mpi/mpiaij.c (revision 242ebda14a69a344bed43bec2e001e417d7cf4e9)
1 
2 #include <../src/mat/impls/aij/mpi/mpiaij.h>   /*I "petscmat.h" I*/
3 #include <petsc-private/vecimpl.h>
4 #include <petscblaslapack.h>
5 
6 /*MC
7    MATAIJ - MATAIJ = "aij" - A matrix type to be used for sparse matrices.
8 
9    This matrix type is identical to MATSEQAIJ when constructed with a single process communicator,
10    and MATMPIAIJ otherwise.  As a result, for single process communicators,
11   MatSeqAIJSetPreallocation is supported, and similarly MatMPIAIJSetPreallocation is supported
12   for communicators controlling multiple processes.  It is recommended that you call both of
13   the above preallocation routines for simplicity.
14 
15    Options Database Keys:
16 . -mat_type aij - sets the matrix type to "aij" during a call to MatSetFromOptions()
17 
18   Developer Notes: Subclasses include MATAIJCUSP, MATAIJCUSPARSE, MATAIJPERM, MATAIJCRL, and also automatically switches over to use inodes when
19    enough exist.
20 
21   Level: beginner
22 
23 .seealso: MatCreateAIJ(), MatCreateSeqAIJ(), MATSEQAIJ,MATMPIAIJ
24 M*/
25 
26 /*MC
27    MATAIJCRL - MATAIJCRL = "aijcrl" - A matrix type to be used for sparse matrices.
28 
29    This matrix type is identical to MATSEQAIJCRL when constructed with a single process communicator,
30    and MATMPIAIJCRL otherwise.  As a result, for single process communicators,
31    MatSeqAIJSetPreallocation() is supported, and similarly MatMPIAIJSetPreallocation() is supported
32   for communicators controlling multiple processes.  It is recommended that you call both of
33   the above preallocation routines for simplicity.
34 
35    Options Database Keys:
36 . -mat_type aijcrl - sets the matrix type to "aijcrl" during a call to MatSetFromOptions()
37 
38   Level: beginner
39 
40 .seealso: MatCreateMPIAIJCRL,MATSEQAIJCRL,MATMPIAIJCRL, MATSEQAIJCRL, MATMPIAIJCRL
41 M*/
42 
43 #undef __FUNCT__
44 #define __FUNCT__ "MatFindNonzeroRows_MPIAIJ"
45 PetscErrorCode MatFindNonzeroRows_MPIAIJ(Mat M,IS *keptrows)
46 {
47   PetscErrorCode  ierr;
48   Mat_MPIAIJ      *mat = (Mat_MPIAIJ*)M->data;
49   Mat_SeqAIJ      *a   = (Mat_SeqAIJ*)mat->A->data;
50   Mat_SeqAIJ      *b   = (Mat_SeqAIJ*)mat->B->data;
51   const PetscInt  *ia,*ib;
52   const MatScalar *aa,*bb;
53   PetscInt        na,nb,i,j,*rows,cnt=0,n0rows;
54   PetscInt        m = M->rmap->n,rstart = M->rmap->rstart;
55 
56   PetscFunctionBegin;
57   *keptrows = 0;
58   ia        = a->i;
59   ib        = b->i;
60   for (i=0; i<m; i++) {
61     na = ia[i+1] - ia[i];
62     nb = ib[i+1] - ib[i];
63     if (!na && !nb) {
64       cnt++;
65       goto ok1;
66     }
67     aa = a->a + ia[i];
68     for (j=0; j<na; j++) {
69       if (aa[j] != 0.0) goto ok1;
70     }
71     bb = b->a + ib[i];
72     for (j=0; j <nb; j++) {
73       if (bb[j] != 0.0) goto ok1;
74     }
75     cnt++;
76 ok1:;
77   }
78   ierr = MPI_Allreduce(&cnt,&n0rows,1,MPIU_INT,MPI_SUM,PetscObjectComm((PetscObject)M));CHKERRQ(ierr);
79   if (!n0rows) PetscFunctionReturn(0);
80   ierr = PetscMalloc((M->rmap->n-cnt)*sizeof(PetscInt),&rows);CHKERRQ(ierr);
81   cnt  = 0;
82   for (i=0; i<m; i++) {
83     na = ia[i+1] - ia[i];
84     nb = ib[i+1] - ib[i];
85     if (!na && !nb) continue;
86     aa = a->a + ia[i];
87     for (j=0; j<na;j++) {
88       if (aa[j] != 0.0) {
89         rows[cnt++] = rstart + i;
90         goto ok2;
91       }
92     }
93     bb = b->a + ib[i];
94     for (j=0; j<nb; j++) {
95       if (bb[j] != 0.0) {
96         rows[cnt++] = rstart + i;
97         goto ok2;
98       }
99     }
100 ok2:;
101   }
102   ierr = ISCreateGeneral(PetscObjectComm((PetscObject)M),cnt,rows,PETSC_OWN_POINTER,keptrows);CHKERRQ(ierr);
103   PetscFunctionReturn(0);
104 }
105 
106 #undef __FUNCT__
107 #define __FUNCT__ "MatFindZeroDiagonals_MPIAIJ"
108 PetscErrorCode MatFindZeroDiagonals_MPIAIJ(Mat M,IS *zrows)
109 {
110   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)M->data;
111   PetscErrorCode ierr;
112   PetscInt       i,rstart,nrows,*rows;
113 
114   PetscFunctionBegin;
115   *zrows = NULL;
116   ierr   = MatFindZeroDiagonals_SeqAIJ_Private(aij->A,&nrows,&rows);CHKERRQ(ierr);
117   ierr   = MatGetOwnershipRange(M,&rstart,NULL);CHKERRQ(ierr);
118   for (i=0; i<nrows; i++) rows[i] += rstart;
119   ierr = ISCreateGeneral(PetscObjectComm((PetscObject)M),nrows,rows,PETSC_OWN_POINTER,zrows);CHKERRQ(ierr);
120   PetscFunctionReturn(0);
121 }
122 
123 #undef __FUNCT__
124 #define __FUNCT__ "MatGetColumnNorms_MPIAIJ"
125 PetscErrorCode MatGetColumnNorms_MPIAIJ(Mat A,NormType type,PetscReal *norms)
126 {
127   PetscErrorCode ierr;
128   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)A->data;
129   PetscInt       i,n,*garray = aij->garray;
130   Mat_SeqAIJ     *a_aij = (Mat_SeqAIJ*) aij->A->data;
131   Mat_SeqAIJ     *b_aij = (Mat_SeqAIJ*) aij->B->data;
132   PetscReal      *work;
133 
134   PetscFunctionBegin;
135   ierr = MatGetSize(A,NULL,&n);CHKERRQ(ierr);
136   ierr = PetscMalloc(n*sizeof(PetscReal),&work);CHKERRQ(ierr);
137   ierr = PetscMemzero(work,n*sizeof(PetscReal));CHKERRQ(ierr);
138   if (type == NORM_2) {
139     for (i=0; i<a_aij->i[aij->A->rmap->n]; i++) {
140       work[A->cmap->rstart + a_aij->j[i]] += PetscAbsScalar(a_aij->a[i]*a_aij->a[i]);
141     }
142     for (i=0; i<b_aij->i[aij->B->rmap->n]; i++) {
143       work[garray[b_aij->j[i]]] += PetscAbsScalar(b_aij->a[i]*b_aij->a[i]);
144     }
145   } else if (type == NORM_1) {
146     for (i=0; i<a_aij->i[aij->A->rmap->n]; i++) {
147       work[A->cmap->rstart + a_aij->j[i]] += PetscAbsScalar(a_aij->a[i]);
148     }
149     for (i=0; i<b_aij->i[aij->B->rmap->n]; i++) {
150       work[garray[b_aij->j[i]]] += PetscAbsScalar(b_aij->a[i]);
151     }
152   } else if (type == NORM_INFINITY) {
153     for (i=0; i<a_aij->i[aij->A->rmap->n]; i++) {
154       work[A->cmap->rstart + a_aij->j[i]] = PetscMax(PetscAbsScalar(a_aij->a[i]), work[A->cmap->rstart + a_aij->j[i]]);
155     }
156     for (i=0; i<b_aij->i[aij->B->rmap->n]; i++) {
157       work[garray[b_aij->j[i]]] = PetscMax(PetscAbsScalar(b_aij->a[i]),work[garray[b_aij->j[i]]]);
158     }
159 
160   } else SETERRQ(PetscObjectComm((PetscObject)A),PETSC_ERR_ARG_WRONG,"Unknown NormType");
161   if (type == NORM_INFINITY) {
162     ierr = MPI_Allreduce(work,norms,n,MPIU_REAL,MPIU_MAX,A->hdr.comm);CHKERRQ(ierr);
163   } else {
164     ierr = MPI_Allreduce(work,norms,n,MPIU_REAL,MPIU_SUM,A->hdr.comm);CHKERRQ(ierr);
165   }
166   ierr = PetscFree(work);CHKERRQ(ierr);
167   if (type == NORM_2) {
168     for (i=0; i<n; i++) norms[i] = PetscSqrtReal(norms[i]);
169   }
170   PetscFunctionReturn(0);
171 }
172 
173 #undef __FUNCT__
174 #define __FUNCT__ "MatDistribute_MPIAIJ"
175 /*
176     Distributes a SeqAIJ matrix across a set of processes. Code stolen from
177     MatLoad_MPIAIJ(). Horrible lack of reuse. Should be a routine for each matrix type.
178 
179     Only for square matrices
180 
181     Used by a preconditioner, hence PETSC_EXTERN
182 */
183 PETSC_EXTERN PetscErrorCode MatDistribute_MPIAIJ(MPI_Comm comm,Mat gmat,PetscInt m,MatReuse reuse,Mat *inmat)
184 {
185   PetscMPIInt    rank,size;
186   PetscInt       *rowners,*dlens,*olens,i,rstart,rend,j,jj,nz,*gmataj,cnt,row,*ld,bses[2];
187   PetscErrorCode ierr;
188   Mat            mat;
189   Mat_SeqAIJ     *gmata;
190   PetscMPIInt    tag;
191   MPI_Status     status;
192   PetscBool      aij;
193   MatScalar      *gmataa,*ao,*ad,*gmataarestore=0;
194 
195   PetscFunctionBegin;
196   CHKMEMQ;
197   ierr = MPI_Comm_rank(comm,&rank);CHKERRQ(ierr);
198   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
199   if (!rank) {
200     ierr = PetscObjectTypeCompare((PetscObject)gmat,MATSEQAIJ,&aij);CHKERRQ(ierr);
201     if (!aij) SETERRQ1(PetscObjectComm((PetscObject)gmat),PETSC_ERR_SUP,"Currently no support for input matrix of type %s\n",((PetscObject)gmat)->type_name);
202   }
203   if (reuse == MAT_INITIAL_MATRIX) {
204     ierr = MatCreate(comm,&mat);CHKERRQ(ierr);
205     ierr = MatSetSizes(mat,m,m,PETSC_DETERMINE,PETSC_DETERMINE);CHKERRQ(ierr);
206     if (!rank) {
207       bses[0] = gmat->rmap->bs;
208       bses[1] = gmat->cmap->bs;
209     }
210     ierr = MPI_Bcast(bses,2,MPIU_INT,0,comm);CHKERRQ(ierr);
211     ierr = MatSetBlockSizes(mat,bses[0],bses[1]);CHKERRQ(ierr);
212     ierr = MatSetType(mat,MATAIJ);CHKERRQ(ierr);
213     ierr = PetscMalloc((size+1)*sizeof(PetscInt),&rowners);CHKERRQ(ierr);
214     ierr = PetscMalloc2(m,PetscInt,&dlens,m,PetscInt,&olens);CHKERRQ(ierr);
215     ierr = MPI_Allgather(&m,1,MPIU_INT,rowners+1,1,MPIU_INT,comm);CHKERRQ(ierr);
216 
217     rowners[0] = 0;
218     for (i=2; i<=size; i++) rowners[i] += rowners[i-1];
219     rstart = rowners[rank];
220     rend   = rowners[rank+1];
221     ierr   = PetscObjectGetNewTag((PetscObject)mat,&tag);CHKERRQ(ierr);
222     if (!rank) {
223       gmata = (Mat_SeqAIJ*) gmat->data;
224       /* send row lengths to all processors */
225       for (i=0; i<m; i++) dlens[i] = gmata->ilen[i];
226       for (i=1; i<size; i++) {
227         ierr = MPI_Send(gmata->ilen + rowners[i],rowners[i+1]-rowners[i],MPIU_INT,i,tag,comm);CHKERRQ(ierr);
228       }
229       /* determine number diagonal and off-diagonal counts */
230       ierr = PetscMemzero(olens,m*sizeof(PetscInt));CHKERRQ(ierr);
231       ierr = PetscMalloc(m*sizeof(PetscInt),&ld);CHKERRQ(ierr);
232       ierr = PetscMemzero(ld,m*sizeof(PetscInt));CHKERRQ(ierr);
233       jj   = 0;
234       for (i=0; i<m; i++) {
235         for (j=0; j<dlens[i]; j++) {
236           if (gmata->j[jj] < rstart) ld[i]++;
237           if (gmata->j[jj] < rstart || gmata->j[jj] >= rend) olens[i]++;
238           jj++;
239         }
240       }
241       /* send column indices to other processes */
242       for (i=1; i<size; i++) {
243         nz   = gmata->i[rowners[i+1]]-gmata->i[rowners[i]];
244         ierr = MPI_Send(&nz,1,MPIU_INT,i,tag,comm);CHKERRQ(ierr);
245         ierr = MPI_Send(gmata->j + gmata->i[rowners[i]],nz,MPIU_INT,i,tag,comm);CHKERRQ(ierr);
246       }
247 
248       /* send numerical values to other processes */
249       for (i=1; i<size; i++) {
250         nz   = gmata->i[rowners[i+1]]-gmata->i[rowners[i]];
251         ierr = MPI_Send(gmata->a + gmata->i[rowners[i]],nz,MPIU_SCALAR,i,tag,comm);CHKERRQ(ierr);
252       }
253       gmataa = gmata->a;
254       gmataj = gmata->j;
255 
256     } else {
257       /* receive row lengths */
258       ierr = MPI_Recv(dlens,m,MPIU_INT,0,tag,comm,&status);CHKERRQ(ierr);
259       /* receive column indices */
260       ierr = MPI_Recv(&nz,1,MPIU_INT,0,tag,comm,&status);CHKERRQ(ierr);
261       ierr = PetscMalloc2(nz,PetscScalar,&gmataa,nz,PetscInt,&gmataj);CHKERRQ(ierr);
262       ierr = MPI_Recv(gmataj,nz,MPIU_INT,0,tag,comm,&status);CHKERRQ(ierr);
263       /* determine number diagonal and off-diagonal counts */
264       ierr = PetscMemzero(olens,m*sizeof(PetscInt));CHKERRQ(ierr);
265       ierr = PetscMalloc(m*sizeof(PetscInt),&ld);CHKERRQ(ierr);
266       ierr = PetscMemzero(ld,m*sizeof(PetscInt));CHKERRQ(ierr);
267       jj   = 0;
268       for (i=0; i<m; i++) {
269         for (j=0; j<dlens[i]; j++) {
270           if (gmataj[jj] < rstart) ld[i]++;
271           if (gmataj[jj] < rstart || gmataj[jj] >= rend) olens[i]++;
272           jj++;
273         }
274       }
275       /* receive numerical values */
276       ierr = PetscMemzero(gmataa,nz*sizeof(PetscScalar));CHKERRQ(ierr);
277       ierr = MPI_Recv(gmataa,nz,MPIU_SCALAR,0,tag,comm,&status);CHKERRQ(ierr);
278     }
279     /* set preallocation */
280     for (i=0; i<m; i++) {
281       dlens[i] -= olens[i];
282     }
283     ierr = MatSeqAIJSetPreallocation(mat,0,dlens);CHKERRQ(ierr);
284     ierr = MatMPIAIJSetPreallocation(mat,0,dlens,0,olens);CHKERRQ(ierr);
285 
286     for (i=0; i<m; i++) {
287       dlens[i] += olens[i];
288     }
289     cnt = 0;
290     for (i=0; i<m; i++) {
291       row  = rstart + i;
292       ierr = MatSetValues(mat,1,&row,dlens[i],gmataj+cnt,gmataa+cnt,INSERT_VALUES);CHKERRQ(ierr);
293       cnt += dlens[i];
294     }
295     if (rank) {
296       ierr = PetscFree2(gmataa,gmataj);CHKERRQ(ierr);
297     }
298     ierr = PetscFree2(dlens,olens);CHKERRQ(ierr);
299     ierr = PetscFree(rowners);CHKERRQ(ierr);
300 
301     ((Mat_MPIAIJ*)(mat->data))->ld = ld;
302 
303     *inmat = mat;
304   } else {   /* column indices are already set; only need to move over numerical values from process 0 */
305     Mat_SeqAIJ *Ad = (Mat_SeqAIJ*)((Mat_MPIAIJ*)((*inmat)->data))->A->data;
306     Mat_SeqAIJ *Ao = (Mat_SeqAIJ*)((Mat_MPIAIJ*)((*inmat)->data))->B->data;
307     mat  = *inmat;
308     ierr = PetscObjectGetNewTag((PetscObject)mat,&tag);CHKERRQ(ierr);
309     if (!rank) {
310       /* send numerical values to other processes */
311       gmata  = (Mat_SeqAIJ*) gmat->data;
312       ierr   = MatGetOwnershipRanges(mat,(const PetscInt**)&rowners);CHKERRQ(ierr);
313       gmataa = gmata->a;
314       for (i=1; i<size; i++) {
315         nz   = gmata->i[rowners[i+1]]-gmata->i[rowners[i]];
316         ierr = MPI_Send(gmataa + gmata->i[rowners[i]],nz,MPIU_SCALAR,i,tag,comm);CHKERRQ(ierr);
317       }
318       nz = gmata->i[rowners[1]]-gmata->i[rowners[0]];
319     } else {
320       /* receive numerical values from process 0*/
321       nz   = Ad->nz + Ao->nz;
322       ierr = PetscMalloc(nz*sizeof(PetscScalar),&gmataa);CHKERRQ(ierr); gmataarestore = gmataa;
323       ierr = MPI_Recv(gmataa,nz,MPIU_SCALAR,0,tag,comm,&status);CHKERRQ(ierr);
324     }
325     /* transfer numerical values into the diagonal A and off diagonal B parts of mat */
326     ld = ((Mat_MPIAIJ*)(mat->data))->ld;
327     ad = Ad->a;
328     ao = Ao->a;
329     if (mat->rmap->n) {
330       i  = 0;
331       nz = ld[i];                                   ierr = PetscMemcpy(ao,gmataa,nz*sizeof(PetscScalar));CHKERRQ(ierr); ao += nz; gmataa += nz;
332       nz = Ad->i[i+1] - Ad->i[i];                   ierr = PetscMemcpy(ad,gmataa,nz*sizeof(PetscScalar));CHKERRQ(ierr); ad += nz; gmataa += nz;
333     }
334     for (i=1; i<mat->rmap->n; i++) {
335       nz = Ao->i[i] - Ao->i[i-1] - ld[i-1] + ld[i]; ierr = PetscMemcpy(ao,gmataa,nz*sizeof(PetscScalar));CHKERRQ(ierr); ao += nz; gmataa += nz;
336       nz = Ad->i[i+1] - Ad->i[i];                   ierr = PetscMemcpy(ad,gmataa,nz*sizeof(PetscScalar));CHKERRQ(ierr); ad += nz; gmataa += nz;
337     }
338     i--;
339     if (mat->rmap->n) {
340       nz = Ao->i[i+1] - Ao->i[i] - ld[i];           ierr = PetscMemcpy(ao,gmataa,nz*sizeof(PetscScalar));CHKERRQ(ierr);
341     }
342     if (rank) {
343       ierr = PetscFree(gmataarestore);CHKERRQ(ierr);
344     }
345   }
346   ierr = MatAssemblyBegin(mat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
347   ierr = MatAssemblyEnd(mat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
348   CHKMEMQ;
349   PetscFunctionReturn(0);
350 }
351 
352 /*
353   Local utility routine that creates a mapping from the global column
354 number to the local number in the off-diagonal part of the local
355 storage of the matrix.  When PETSC_USE_CTABLE is used this is scalable at
356 a slightly higher hash table cost; without it it is not scalable (each processor
357 has an order N integer array but is fast to acess.
358 */
359 #undef __FUNCT__
360 #define __FUNCT__ "MatCreateColmap_MPIAIJ_Private"
361 PetscErrorCode MatCreateColmap_MPIAIJ_Private(Mat mat)
362 {
363   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
364   PetscErrorCode ierr;
365   PetscInt       n = aij->B->cmap->n,i;
366 
367   PetscFunctionBegin;
368   if (!aij->garray) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_PLIB,"MPIAIJ Matrix was assembled but is missing garray");
369 #if defined(PETSC_USE_CTABLE)
370   ierr = PetscTableCreate(n,mat->cmap->N+1,&aij->colmap);CHKERRQ(ierr);
371   for (i=0; i<n; i++) {
372     ierr = PetscTableAdd(aij->colmap,aij->garray[i]+1,i+1,INSERT_VALUES);CHKERRQ(ierr);
373   }
374 #else
375   ierr = PetscMalloc((mat->cmap->N+1)*sizeof(PetscInt),&aij->colmap);CHKERRQ(ierr);
376   ierr = PetscLogObjectMemory(mat,mat->cmap->N*sizeof(PetscInt));CHKERRQ(ierr);
377   ierr = PetscMemzero(aij->colmap,mat->cmap->N*sizeof(PetscInt));CHKERRQ(ierr);
378   for (i=0; i<n; i++) aij->colmap[aij->garray[i]] = i+1;
379 #endif
380   PetscFunctionReturn(0);
381 }
382 
383 #define MatSetValues_SeqAIJ_A_Private(row,col,value,addv) \
384 { \
385     if (col <= lastcol1)  low1 = 0;     \
386     else                 high1 = nrow1; \
387     lastcol1 = col;\
388     while (high1-low1 > 5) { \
389       t = (low1+high1)/2; \
390       if (rp1[t] > col) high1 = t; \
391       else              low1  = t; \
392     } \
393       for (_i=low1; _i<high1; _i++) { \
394         if (rp1[_i] > col) break; \
395         if (rp1[_i] == col) { \
396           if (addv == ADD_VALUES) ap1[_i] += value;   \
397           else                    ap1[_i] = value; \
398           goto a_noinsert; \
399         } \
400       }  \
401       if (value == 0.0 && ignorezeroentries) {low1 = 0; high1 = nrow1;goto a_noinsert;} \
402       if (nonew == 1) {low1 = 0; high1 = nrow1; goto a_noinsert;}                \
403       if (nonew == -1) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Inserting a new nonzero (%D, %D) into matrix", row, col); \
404       MatSeqXAIJReallocateAIJ(A,am,1,nrow1,row,col,rmax1,aa,ai,aj,rp1,ap1,aimax,nonew,MatScalar); \
405       N = nrow1++ - 1; a->nz++; high1++; \
406       /* shift up all the later entries in this row */ \
407       for (ii=N; ii>=_i; ii--) { \
408         rp1[ii+1] = rp1[ii]; \
409         ap1[ii+1] = ap1[ii]; \
410       } \
411       rp1[_i] = col;  \
412       ap1[_i] = value;  \
413       a_noinsert: ; \
414       ailen[row] = nrow1; \
415 }
416 
417 
418 #define MatSetValues_SeqAIJ_B_Private(row,col,value,addv) \
419   { \
420     if (col <= lastcol2) low2 = 0;                        \
421     else high2 = nrow2;                                   \
422     lastcol2 = col;                                       \
423     while (high2-low2 > 5) {                              \
424       t = (low2+high2)/2;                                 \
425       if (rp2[t] > col) high2 = t;                        \
426       else             low2  = t;                         \
427     }                                                     \
428     for (_i=low2; _i<high2; _i++) {                       \
429       if (rp2[_i] > col) break;                           \
430       if (rp2[_i] == col) {                               \
431         if (addv == ADD_VALUES) ap2[_i] += value;         \
432         else                    ap2[_i] = value;          \
433         goto b_noinsert;                                  \
434       }                                                   \
435     }                                                     \
436     if (value == 0.0 && ignorezeroentries) {low2 = 0; high2 = nrow2; goto b_noinsert;} \
437     if (nonew == 1) {low2 = 0; high2 = nrow2; goto b_noinsert;}                        \
438     if (nonew == -1) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Inserting a new nonzero (%D, %D) into matrix", row, col); \
439     MatSeqXAIJReallocateAIJ(B,bm,1,nrow2,row,col,rmax2,ba,bi,bj,rp2,ap2,bimax,nonew,MatScalar); \
440     N = nrow2++ - 1; b->nz++; high2++;                    \
441     /* shift up all the later entries in this row */      \
442     for (ii=N; ii>=_i; ii--) {                            \
443       rp2[ii+1] = rp2[ii];                                \
444       ap2[ii+1] = ap2[ii];                                \
445     }                                                     \
446     rp2[_i] = col;                                        \
447     ap2[_i] = value;                                      \
448     b_noinsert: ;                                         \
449     bilen[row] = nrow2;                                   \
450   }
451 
452 #undef __FUNCT__
453 #define __FUNCT__ "MatSetValuesRow_MPIAIJ"
454 PetscErrorCode MatSetValuesRow_MPIAIJ(Mat A,PetscInt row,const PetscScalar v[])
455 {
456   Mat_MPIAIJ     *mat = (Mat_MPIAIJ*)A->data;
457   Mat_SeqAIJ     *a   = (Mat_SeqAIJ*)mat->A->data,*b = (Mat_SeqAIJ*)mat->B->data;
458   PetscErrorCode ierr;
459   PetscInt       l,*garray = mat->garray,diag;
460 
461   PetscFunctionBegin;
462   /* code only works for square matrices A */
463 
464   /* find size of row to the left of the diagonal part */
465   ierr = MatGetOwnershipRange(A,&diag,0);CHKERRQ(ierr);
466   row  = row - diag;
467   for (l=0; l<b->i[row+1]-b->i[row]; l++) {
468     if (garray[b->j[b->i[row]+l]] > diag) break;
469   }
470   ierr = PetscMemcpy(b->a+b->i[row],v,l*sizeof(PetscScalar));CHKERRQ(ierr);
471 
472   /* diagonal part */
473   ierr = PetscMemcpy(a->a+a->i[row],v+l,(a->i[row+1]-a->i[row])*sizeof(PetscScalar));CHKERRQ(ierr);
474 
475   /* right of diagonal part */
476   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);
477   PetscFunctionReturn(0);
478 }
479 
480 #undef __FUNCT__
481 #define __FUNCT__ "MatSetValues_MPIAIJ"
482 PetscErrorCode MatSetValues_MPIAIJ(Mat mat,PetscInt m,const PetscInt im[],PetscInt n,const PetscInt in[],const PetscScalar v[],InsertMode addv)
483 {
484   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
485   PetscScalar    value;
486   PetscErrorCode ierr;
487   PetscInt       i,j,rstart  = mat->rmap->rstart,rend = mat->rmap->rend;
488   PetscInt       cstart      = mat->cmap->rstart,cend = mat->cmap->rend,row,col;
489   PetscBool      roworiented = aij->roworiented;
490 
491   /* Some Variables required in the macro */
492   Mat        A                 = aij->A;
493   Mat_SeqAIJ *a                = (Mat_SeqAIJ*)A->data;
494   PetscInt   *aimax            = a->imax,*ai = a->i,*ailen = a->ilen,*aj = a->j;
495   MatScalar  *aa               = a->a;
496   PetscBool  ignorezeroentries = a->ignorezeroentries;
497   Mat        B                 = aij->B;
498   Mat_SeqAIJ *b                = (Mat_SeqAIJ*)B->data;
499   PetscInt   *bimax            = b->imax,*bi = b->i,*bilen = b->ilen,*bj = b->j,bm = aij->B->rmap->n,am = aij->A->rmap->n;
500   MatScalar  *ba               = b->a;
501 
502   PetscInt  *rp1,*rp2,ii,nrow1,nrow2,_i,rmax1,rmax2,N,low1,high1,low2,high2,t,lastcol1,lastcol2;
503   PetscInt  nonew;
504   MatScalar *ap1,*ap2;
505 
506   PetscFunctionBegin;
507   if (v) PetscValidScalarPointer(v,6);
508   for (i=0; i<m; i++) {
509     if (im[i] < 0) continue;
510 #if defined(PETSC_USE_DEBUG)
511     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);
512 #endif
513     if (im[i] >= rstart && im[i] < rend) {
514       row      = im[i] - rstart;
515       lastcol1 = -1;
516       rp1      = aj + ai[row];
517       ap1      = aa + ai[row];
518       rmax1    = aimax[row];
519       nrow1    = ailen[row];
520       low1     = 0;
521       high1    = nrow1;
522       lastcol2 = -1;
523       rp2      = bj + bi[row];
524       ap2      = ba + bi[row];
525       rmax2    = bimax[row];
526       nrow2    = bilen[row];
527       low2     = 0;
528       high2    = nrow2;
529 
530       for (j=0; j<n; j++) {
531         if (v) {
532           if (roworiented) value = v[i*n+j];
533           else             value = v[i+j*m];
534         } else value = 0.0;
535         if (ignorezeroentries && value == 0.0 && (addv == ADD_VALUES)) continue;
536         if (in[j] >= cstart && in[j] < cend) {
537           col   = in[j] - cstart;
538           nonew = a->nonew;
539           MatSetValues_SeqAIJ_A_Private(row,col,value,addv);
540         } else if (in[j] < 0) continue;
541 #if defined(PETSC_USE_DEBUG)
542         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);
543 #endif
544         else {
545           if (mat->was_assembled) {
546             if (!aij->colmap) {
547               ierr = MatCreateColmap_MPIAIJ_Private(mat);CHKERRQ(ierr);
548             }
549 #if defined(PETSC_USE_CTABLE)
550             ierr = PetscTableFind(aij->colmap,in[j]+1,&col);CHKERRQ(ierr);
551             col--;
552 #else
553             col = aij->colmap[in[j]] - 1;
554 #endif
555             if (col < 0 && !((Mat_SeqAIJ*)(aij->B->data))->nonew) {
556               ierr = MatDisAssemble_MPIAIJ(mat);CHKERRQ(ierr);
557               col  =  in[j];
558               /* Reinitialize the variables required by MatSetValues_SeqAIJ_B_Private() */
559               B     = aij->B;
560               b     = (Mat_SeqAIJ*)B->data;
561               bimax = b->imax; bi = b->i; bilen = b->ilen; bj = b->j; ba = b->a;
562               rp2   = bj + bi[row];
563               ap2   = ba + bi[row];
564               rmax2 = bimax[row];
565               nrow2 = bilen[row];
566               low2  = 0;
567               high2 = nrow2;
568               bm    = aij->B->rmap->n;
569               ba    = b->a;
570             } else if (col < 0) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Inserting a new nonzero (%D, %D) into matrix", im[i], in[j]);
571           } else col = in[j];
572           nonew = b->nonew;
573           MatSetValues_SeqAIJ_B_Private(row,col,value,addv);
574         }
575       }
576     } else {
577       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]);
578       if (!aij->donotstash) {
579         mat->assembled = PETSC_FALSE;
580         if (roworiented) {
581           ierr = MatStashValuesRow_Private(&mat->stash,im[i],n,in,v+i*n,(PetscBool)(ignorezeroentries && (addv == ADD_VALUES)));CHKERRQ(ierr);
582         } else {
583           ierr = MatStashValuesCol_Private(&mat->stash,im[i],n,in,v+i,m,(PetscBool)(ignorezeroentries && (addv == ADD_VALUES)));CHKERRQ(ierr);
584         }
585       }
586     }
587   }
588   PetscFunctionReturn(0);
589 }
590 
591 #undef __FUNCT__
592 #define __FUNCT__ "MatGetValues_MPIAIJ"
593 PetscErrorCode MatGetValues_MPIAIJ(Mat mat,PetscInt m,const PetscInt idxm[],PetscInt n,const PetscInt idxn[],PetscScalar v[])
594 {
595   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
596   PetscErrorCode ierr;
597   PetscInt       i,j,rstart = mat->rmap->rstart,rend = mat->rmap->rend;
598   PetscInt       cstart = mat->cmap->rstart,cend = mat->cmap->rend,row,col;
599 
600   PetscFunctionBegin;
601   for (i=0; i<m; i++) {
602     if (idxm[i] < 0) continue; /* SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Negative row: %D",idxm[i]);*/
603     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);
604     if (idxm[i] >= rstart && idxm[i] < rend) {
605       row = idxm[i] - rstart;
606       for (j=0; j<n; j++) {
607         if (idxn[j] < 0) continue; /* SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Negative column: %D",idxn[j]); */
608         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);
609         if (idxn[j] >= cstart && idxn[j] < cend) {
610           col  = idxn[j] - cstart;
611           ierr = MatGetValues(aij->A,1,&row,1,&col,v+i*n+j);CHKERRQ(ierr);
612         } else {
613           if (!aij->colmap) {
614             ierr = MatCreateColmap_MPIAIJ_Private(mat);CHKERRQ(ierr);
615           }
616 #if defined(PETSC_USE_CTABLE)
617           ierr = PetscTableFind(aij->colmap,idxn[j]+1,&col);CHKERRQ(ierr);
618           col--;
619 #else
620           col = aij->colmap[idxn[j]] - 1;
621 #endif
622           if ((col < 0) || (aij->garray[col] != idxn[j])) *(v+i*n+j) = 0.0;
623           else {
624             ierr = MatGetValues(aij->B,1,&row,1,&col,v+i*n+j);CHKERRQ(ierr);
625           }
626         }
627       }
628     } else SETERRQ(PETSC_COMM_SELF,PETSC_ERR_SUP,"Only local values currently supported");
629   }
630   PetscFunctionReturn(0);
631 }
632 
633 extern PetscErrorCode MatMultDiagonalBlock_MPIAIJ(Mat,Vec,Vec);
634 
635 #undef __FUNCT__
636 #define __FUNCT__ "MatAssemblyBegin_MPIAIJ"
637 PetscErrorCode MatAssemblyBegin_MPIAIJ(Mat mat,MatAssemblyType mode)
638 {
639   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
640   PetscErrorCode ierr;
641   PetscInt       nstash,reallocs;
642   InsertMode     addv;
643 
644   PetscFunctionBegin;
645   if (aij->donotstash || mat->nooffprocentries) PetscFunctionReturn(0);
646 
647   /* make sure all processors are either in INSERTMODE or ADDMODE */
648   ierr = MPI_Allreduce((PetscEnum*)&mat->insertmode,(PetscEnum*)&addv,1,MPIU_ENUM,MPI_BOR,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
649   if (addv == (ADD_VALUES|INSERT_VALUES)) SETERRQ(PetscObjectComm((PetscObject)mat),PETSC_ERR_ARG_WRONGSTATE,"Some processors inserted others added");
650   mat->insertmode = addv; /* in case this processor had no cache */
651 
652   ierr = MatStashScatterBegin_Private(mat,&mat->stash,mat->rmap->range);CHKERRQ(ierr);
653   ierr = MatStashGetInfo_Private(&mat->stash,&nstash,&reallocs);CHKERRQ(ierr);
654   ierr = PetscInfo2(aij->A,"Stash has %D entries, uses %D mallocs.\n",nstash,reallocs);CHKERRQ(ierr);
655   PetscFunctionReturn(0);
656 }
657 
658 #undef __FUNCT__
659 #define __FUNCT__ "MatAssemblyEnd_MPIAIJ"
660 PetscErrorCode MatAssemblyEnd_MPIAIJ(Mat mat,MatAssemblyType mode)
661 {
662   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
663   Mat_SeqAIJ     *a   = (Mat_SeqAIJ*)aij->A->data;
664   PetscErrorCode ierr;
665   PetscMPIInt    n;
666   PetscInt       i,j,rstart,ncols,flg;
667   PetscInt       *row,*col;
668   PetscBool      other_disassembled;
669   PetscScalar    *val;
670   InsertMode     addv = mat->insertmode;
671 
672   /* do not use 'b = (Mat_SeqAIJ*)aij->B->data' as B can be reset in disassembly */
673 
674   PetscFunctionBegin;
675   if (!aij->donotstash && !mat->nooffprocentries) {
676     while (1) {
677       ierr = MatStashScatterGetMesg_Private(&mat->stash,&n,&row,&col,&val,&flg);CHKERRQ(ierr);
678       if (!flg) break;
679 
680       for (i=0; i<n; ) {
681         /* Now identify the consecutive vals belonging to the same row */
682         for (j=i,rstart=row[j]; j<n; j++) {
683           if (row[j] != rstart) break;
684         }
685         if (j < n) ncols = j-i;
686         else       ncols = n-i;
687         /* Now assemble all these values with a single function call */
688         ierr = MatSetValues_MPIAIJ(mat,1,row+i,ncols,col+i,val+i,addv);CHKERRQ(ierr);
689 
690         i = j;
691       }
692     }
693     ierr = MatStashScatterEnd_Private(&mat->stash);CHKERRQ(ierr);
694   }
695   ierr = MatAssemblyBegin(aij->A,mode);CHKERRQ(ierr);
696   ierr = MatAssemblyEnd(aij->A,mode);CHKERRQ(ierr);
697 
698   /* determine if any processor has disassembled, if so we must
699      also disassemble ourselfs, in order that we may reassemble. */
700   /*
701      if nonzero structure of submatrix B cannot change then we know that
702      no processor disassembled thus we can skip this stuff
703   */
704   if (!((Mat_SeqAIJ*)aij->B->data)->nonew) {
705     ierr = MPI_Allreduce(&mat->was_assembled,&other_disassembled,1,MPIU_BOOL,MPI_PROD,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
706     if (mat->was_assembled && !other_disassembled) {
707       ierr = MatDisAssemble_MPIAIJ(mat);CHKERRQ(ierr);
708     }
709   }
710   if (!mat->was_assembled && mode == MAT_FINAL_ASSEMBLY) {
711     ierr = MatSetUpMultiply_MPIAIJ(mat);CHKERRQ(ierr);
712   }
713   ierr = MatSetOption(aij->B,MAT_USE_INODES,PETSC_FALSE);CHKERRQ(ierr);
714   ierr = MatSetOption(aij->B,MAT_CHECK_COMPRESSED_ROW,PETSC_FALSE);CHKERRQ(ierr);
715   ierr = MatAssemblyBegin(aij->B,mode);CHKERRQ(ierr);
716   ierr = MatAssemblyEnd(aij->B,mode);CHKERRQ(ierr);
717 
718   ierr = PetscFree2(aij->rowvalues,aij->rowindices);CHKERRQ(ierr);
719 
720   aij->rowvalues = 0;
721 
722   /* used by MatAXPY() */
723   a->xtoy = 0; ((Mat_SeqAIJ*)aij->B->data)->xtoy = 0;   /* b->xtoy = 0 */
724   a->XtoY = 0; ((Mat_SeqAIJ*)aij->B->data)->XtoY = 0;   /* b->XtoY = 0 */
725 
726   ierr = VecDestroy(&aij->diag);CHKERRQ(ierr);
727   if (a->inode.size) mat->ops->multdiagonalblock = MatMultDiagonalBlock_MPIAIJ;
728   PetscFunctionReturn(0);
729 }
730 
731 #undef __FUNCT__
732 #define __FUNCT__ "MatZeroEntries_MPIAIJ"
733 PetscErrorCode MatZeroEntries_MPIAIJ(Mat A)
734 {
735   Mat_MPIAIJ     *l = (Mat_MPIAIJ*)A->data;
736   PetscErrorCode ierr;
737 
738   PetscFunctionBegin;
739   ierr = MatZeroEntries(l->A);CHKERRQ(ierr);
740   ierr = MatZeroEntries(l->B);CHKERRQ(ierr);
741   PetscFunctionReturn(0);
742 }
743 
744 #undef __FUNCT__
745 #define __FUNCT__ "MatZeroRows_MPIAIJ"
746 PetscErrorCode MatZeroRows_MPIAIJ(Mat A,PetscInt N,const PetscInt rows[],PetscScalar diag,Vec x,Vec b)
747 {
748   Mat_MPIAIJ        *l = (Mat_MPIAIJ*)A->data;
749   PetscErrorCode    ierr;
750   PetscMPIInt       size = l->size,imdex,n,rank = l->rank,tag = ((PetscObject)A)->tag,lastidx = -1;
751   PetscInt          i,*owners = A->rmap->range;
752   PetscInt          *nprocs,j,idx,nsends,row;
753   PetscInt          nmax,*svalues,*starts,*owner,nrecvs;
754   PetscInt          *rvalues,count,base,slen,*source;
755   PetscInt          *lens,*lrows,*values,rstart=A->rmap->rstart;
756   MPI_Comm          comm;
757   MPI_Request       *send_waits,*recv_waits;
758   MPI_Status        recv_status,*send_status;
759   const PetscScalar *xx;
760   PetscScalar       *bb;
761 #if defined(PETSC_DEBUG)
762   PetscBool found = PETSC_FALSE;
763 #endif
764 
765   PetscFunctionBegin;
766   ierr = PetscObjectGetComm((PetscObject)A,&comm);CHKERRQ(ierr);
767   /*  first count number of contributors to each processor */
768   ierr = PetscMalloc(2*size*sizeof(PetscInt),&nprocs);CHKERRQ(ierr);
769   ierr = PetscMemzero(nprocs,2*size*sizeof(PetscInt));CHKERRQ(ierr);
770   ierr = PetscMalloc((N+1)*sizeof(PetscInt),&owner);CHKERRQ(ierr); /* see note*/
771   j    = 0;
772   for (i=0; i<N; i++) {
773     if (lastidx > (idx = rows[i])) j = 0;
774     lastidx = idx;
775     for (; j<size; j++) {
776       if (idx >= owners[j] && idx < owners[j+1]) {
777         nprocs[2*j]++;
778         nprocs[2*j+1] = 1;
779         owner[i]      = j;
780 #if defined(PETSC_DEBUG)
781         found = PETSC_TRUE;
782 #endif
783         break;
784       }
785     }
786 #if defined(PETSC_DEBUG)
787     if (!found) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Index out of range");
788     found = PETSC_FALSE;
789 #endif
790   }
791   nsends = 0;
792   for (i=0; i<size; i++) nsends += nprocs[2*i+1];
793 
794   if (A->nooffproczerorows) {
795     if (nsends > 1) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONG,"You called MatSetOption(,MAT_NO_OFF_PROC_ZERO_ROWS,PETSC_TRUE) but set an off process zero row");
796     nrecvs = nsends;
797     nmax   = N;
798   } else {
799     /* inform other processors of number of messages and max length*/
800     ierr = PetscMaxSum(comm,nprocs,&nmax,&nrecvs);CHKERRQ(ierr);
801   }
802 
803   /* post receives:   */
804   ierr = PetscMalloc((nrecvs+1)*(nmax+1)*sizeof(PetscInt),&rvalues);CHKERRQ(ierr);
805   ierr = PetscMalloc((nrecvs+1)*sizeof(MPI_Request),&recv_waits);CHKERRQ(ierr);
806   for (i=0; i<nrecvs; i++) {
807     ierr = MPI_Irecv(rvalues+nmax*i,nmax,MPIU_INT,MPI_ANY_SOURCE,tag,comm,recv_waits+i);CHKERRQ(ierr);
808   }
809 
810   /* do sends:
811       1) starts[i] gives the starting index in svalues for stuff going to
812          the ith processor
813   */
814   ierr = PetscMalloc((N+1)*sizeof(PetscInt),&svalues);CHKERRQ(ierr);
815   ierr = PetscMalloc((nsends+1)*sizeof(MPI_Request),&send_waits);CHKERRQ(ierr);
816   ierr = PetscMalloc((size+1)*sizeof(PetscInt),&starts);CHKERRQ(ierr);
817 
818   starts[0] = 0;
819   for (i=1; i<size; i++) starts[i] = starts[i-1] + nprocs[2*i-2];
820   for (i=0; i<N; i++) svalues[starts[owner[i]]++] = rows[i];
821 
822   starts[0] = 0;
823   for (i=1; i<size+1; i++) starts[i] = starts[i-1] + nprocs[2*i-2];
824   count = 0;
825   for (i=0; i<size; i++) {
826     if (nprocs[2*i+1]) {
827       ierr = MPI_Isend(svalues+starts[i],nprocs[2*i],MPIU_INT,i,tag,comm,send_waits+count++);CHKERRQ(ierr);
828     }
829   }
830   ierr = PetscFree(starts);CHKERRQ(ierr);
831 
832   base = owners[rank];
833 
834   /*  wait on receives */
835   ierr  = PetscMalloc2(nrecvs,PetscInt,&lens,nrecvs,PetscInt,&source);CHKERRQ(ierr);
836   count = nrecvs; slen = 0;
837   while (count) {
838     ierr = MPI_Waitany(nrecvs,recv_waits,&imdex,&recv_status);CHKERRQ(ierr);
839     /* unpack receives into our local space */
840     ierr = MPI_Get_count(&recv_status,MPIU_INT,&n);CHKERRQ(ierr);
841 
842     source[imdex] = recv_status.MPI_SOURCE;
843     lens[imdex]   = n;
844     slen         += n;
845     count--;
846   }
847   ierr = PetscFree(recv_waits);CHKERRQ(ierr);
848 
849   /* move the data into the send scatter */
850   ierr  = PetscMalloc((slen+1)*sizeof(PetscInt),&lrows);CHKERRQ(ierr);
851   count = 0;
852   for (i=0; i<nrecvs; i++) {
853     values = rvalues + i*nmax;
854     for (j=0; j<lens[i]; j++) lrows[count++] = values[j] - base;
855   }
856   ierr = PetscFree(rvalues);CHKERRQ(ierr);
857   ierr = PetscFree2(lens,source);CHKERRQ(ierr);
858   ierr = PetscFree(owner);CHKERRQ(ierr);
859   ierr = PetscFree(nprocs);CHKERRQ(ierr);
860 
861   /* fix right hand side if needed */
862   if (x && b) {
863     ierr = VecGetArrayRead(x,&xx);CHKERRQ(ierr);
864     ierr = VecGetArray(b,&bb);CHKERRQ(ierr);
865     for (i=0; i<slen; i++) bb[lrows[i]] = diag*xx[lrows[i]];
866     ierr = VecRestoreArrayRead(x,&xx);CHKERRQ(ierr);
867     ierr = VecRestoreArray(b,&bb);CHKERRQ(ierr);
868   }
869   /*
870         Zero the required rows. If the "diagonal block" of the matrix
871      is square and the user wishes to set the diagonal we use separate
872      code so that MatSetValues() is not called for each diagonal allocating
873      new memory, thus calling lots of mallocs and slowing things down.
874 
875   */
876   /* must zero l->B before l->A because the (diag) case below may put values into l->B*/
877   ierr = MatZeroRows(l->B,slen,lrows,0.0,0,0);CHKERRQ(ierr);
878   if ((diag != 0.0) && (l->A->rmap->N == l->A->cmap->N)) {
879     ierr = MatZeroRows(l->A,slen,lrows,diag,0,0);CHKERRQ(ierr);
880   } else if (diag != 0.0) {
881     ierr = MatZeroRows(l->A,slen,lrows,0.0,0,0);CHKERRQ(ierr);
882     if (((Mat_SeqAIJ*)l->A->data)->nonew) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_SUP,"MatZeroRows() on rectangular matrices cannot be used with the Mat options\nMAT_NEW_NONZERO_LOCATIONS,MAT_NEW_NONZERO_LOCATION_ERR,MAT_NEW_NONZERO_ALLOCATION_ERR");
883     for (i = 0; i < slen; i++) {
884       row  = lrows[i] + rstart;
885       ierr = MatSetValues(A,1,&row,1,&row,&diag,INSERT_VALUES);CHKERRQ(ierr);
886     }
887     ierr = MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
888     ierr = MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
889   } else {
890     ierr = MatZeroRows(l->A,slen,lrows,0.0,0,0);CHKERRQ(ierr);
891   }
892   ierr = PetscFree(lrows);CHKERRQ(ierr);
893 
894   /* wait on sends */
895   if (nsends) {
896     ierr = PetscMalloc(nsends*sizeof(MPI_Status),&send_status);CHKERRQ(ierr);
897     ierr = MPI_Waitall(nsends,send_waits,send_status);CHKERRQ(ierr);
898     ierr = PetscFree(send_status);CHKERRQ(ierr);
899   }
900   ierr = PetscFree(send_waits);CHKERRQ(ierr);
901   ierr = PetscFree(svalues);CHKERRQ(ierr);
902   PetscFunctionReturn(0);
903 }
904 
905 #undef __FUNCT__
906 #define __FUNCT__ "MatZeroRowsColumns_MPIAIJ"
907 PetscErrorCode MatZeroRowsColumns_MPIAIJ(Mat A,PetscInt N,const PetscInt rows[],PetscScalar diag,Vec x,Vec b)
908 {
909   Mat_MPIAIJ        *l = (Mat_MPIAIJ*)A->data;
910   PetscErrorCode    ierr;
911   PetscMPIInt       size = l->size,imdex,n,rank = l->rank,tag = ((PetscObject)A)->tag,lastidx = -1;
912   PetscInt          i,*owners = A->rmap->range;
913   PetscInt          *nprocs,j,idx,nsends;
914   PetscInt          nmax,*svalues,*starts,*owner,nrecvs;
915   PetscInt          *rvalues,count,base,slen,*source;
916   PetscInt          *lens,*lrows,*values,m;
917   MPI_Comm          comm;
918   MPI_Request       *send_waits,*recv_waits;
919   MPI_Status        recv_status,*send_status;
920   const PetscScalar *xx;
921   PetscScalar       *bb,*mask;
922   Vec               xmask,lmask;
923   Mat_SeqAIJ        *aij = (Mat_SeqAIJ*)l->B->data;
924   const PetscInt    *aj, *ii,*ridx;
925   PetscScalar       *aa;
926 #if defined(PETSC_DEBUG)
927   PetscBool found = PETSC_FALSE;
928 #endif
929 
930   PetscFunctionBegin;
931   ierr = PetscObjectGetComm((PetscObject)A,&comm);CHKERRQ(ierr);
932   /*  first count number of contributors to each processor */
933   ierr = PetscMalloc(2*size*sizeof(PetscInt),&nprocs);CHKERRQ(ierr);
934   ierr = PetscMemzero(nprocs,2*size*sizeof(PetscInt));CHKERRQ(ierr);
935   ierr = PetscMalloc((N+1)*sizeof(PetscInt),&owner);CHKERRQ(ierr); /* see note*/
936   j    = 0;
937   for (i=0; i<N; i++) {
938     if (lastidx > (idx = rows[i])) j = 0;
939     lastidx = idx;
940     for (; j<size; j++) {
941       if (idx >= owners[j] && idx < owners[j+1]) {
942         nprocs[2*j]++;
943         nprocs[2*j+1] = 1;
944         owner[i]      = j;
945 #if defined(PETSC_DEBUG)
946         found = PETSC_TRUE;
947 #endif
948         break;
949       }
950     }
951 #if defined(PETSC_DEBUG)
952     if (!found) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Index out of range");
953     found = PETSC_FALSE;
954 #endif
955   }
956   nsends = 0;  for (i=0; i<size; i++) nsends += nprocs[2*i+1];
957 
958   /* inform other processors of number of messages and max length*/
959   ierr = PetscMaxSum(comm,nprocs,&nmax,&nrecvs);CHKERRQ(ierr);
960 
961   /* post receives:   */
962   ierr = PetscMalloc((nrecvs+1)*(nmax+1)*sizeof(PetscInt),&rvalues);CHKERRQ(ierr);
963   ierr = PetscMalloc((nrecvs+1)*sizeof(MPI_Request),&recv_waits);CHKERRQ(ierr);
964   for (i=0; i<nrecvs; i++) {
965     ierr = MPI_Irecv(rvalues+nmax*i,nmax,MPIU_INT,MPI_ANY_SOURCE,tag,comm,recv_waits+i);CHKERRQ(ierr);
966   }
967 
968   /* do sends:
969       1) starts[i] gives the starting index in svalues for stuff going to
970          the ith processor
971   */
972   ierr = PetscMalloc((N+1)*sizeof(PetscInt),&svalues);CHKERRQ(ierr);
973   ierr = PetscMalloc((nsends+1)*sizeof(MPI_Request),&send_waits);CHKERRQ(ierr);
974   ierr = PetscMalloc((size+1)*sizeof(PetscInt),&starts);CHKERRQ(ierr);
975 
976   starts[0] = 0;
977   for (i=1; i<size; i++) starts[i] = starts[i-1] + nprocs[2*i-2];
978   for (i=0; i<N; i++) svalues[starts[owner[i]]++] = rows[i];
979 
980   starts[0] = 0;
981   for (i=1; i<size+1; i++) starts[i] = starts[i-1] + nprocs[2*i-2];
982   count = 0;
983   for (i=0; i<size; i++) {
984     if (nprocs[2*i+1]) {
985       ierr = MPI_Isend(svalues+starts[i],nprocs[2*i],MPIU_INT,i,tag,comm,send_waits+count++);CHKERRQ(ierr);
986     }
987   }
988   ierr = PetscFree(starts);CHKERRQ(ierr);
989 
990   base = owners[rank];
991 
992   /*  wait on receives */
993   ierr  = PetscMalloc2(nrecvs,PetscInt,&lens,nrecvs,PetscInt,&source);CHKERRQ(ierr);
994   count = nrecvs; slen = 0;
995   while (count) {
996     ierr = MPI_Waitany(nrecvs,recv_waits,&imdex,&recv_status);CHKERRQ(ierr);
997     /* unpack receives into our local space */
998     ierr = MPI_Get_count(&recv_status,MPIU_INT,&n);CHKERRQ(ierr);
999 
1000     source[imdex] = recv_status.MPI_SOURCE;
1001     lens[imdex]   = n;
1002     slen         += n;
1003     count--;
1004   }
1005   ierr = PetscFree(recv_waits);CHKERRQ(ierr);
1006 
1007   /* move the data into the send scatter */
1008   ierr  = PetscMalloc((slen+1)*sizeof(PetscInt),&lrows);CHKERRQ(ierr);
1009   count = 0;
1010   for (i=0; i<nrecvs; i++) {
1011     values = rvalues + i*nmax;
1012     for (j=0; j<lens[i]; j++) lrows[count++] = values[j] - base;
1013   }
1014   ierr = PetscFree(rvalues);CHKERRQ(ierr);
1015   ierr = PetscFree2(lens,source);CHKERRQ(ierr);
1016   ierr = PetscFree(owner);CHKERRQ(ierr);
1017   ierr = PetscFree(nprocs);CHKERRQ(ierr);
1018   /* lrows are the local rows to be zeroed, slen is the number of local rows */
1019 
1020   /* zero diagonal part of matrix */
1021   ierr = MatZeroRowsColumns(l->A,slen,lrows,diag,x,b);CHKERRQ(ierr);
1022 
1023   /* handle off diagonal part of matrix */
1024   ierr = MatGetVecs(A,&xmask,NULL);CHKERRQ(ierr);
1025   ierr = VecDuplicate(l->lvec,&lmask);CHKERRQ(ierr);
1026   ierr = VecGetArray(xmask,&bb);CHKERRQ(ierr);
1027   for (i=0; i<slen; i++) bb[lrows[i]] = 1;
1028   ierr = VecRestoreArray(xmask,&bb);CHKERRQ(ierr);
1029   ierr = VecScatterBegin(l->Mvctx,xmask,lmask,ADD_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1030   ierr = VecScatterEnd(l->Mvctx,xmask,lmask,ADD_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1031   ierr = VecDestroy(&xmask);CHKERRQ(ierr);
1032   if (x) {
1033     ierr = VecScatterBegin(l->Mvctx,x,l->lvec,ADD_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1034     ierr = VecScatterEnd(l->Mvctx,x,l->lvec,ADD_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1035     ierr = VecGetArrayRead(l->lvec,&xx);CHKERRQ(ierr);
1036     ierr = VecGetArray(b,&bb);CHKERRQ(ierr);
1037   }
1038   ierr = VecGetArray(lmask,&mask);CHKERRQ(ierr);
1039 
1040   /* remove zeroed rows of off diagonal matrix */
1041   ii = aij->i;
1042   for (i=0; i<slen; i++) {
1043     ierr = PetscMemzero(aij->a + ii[lrows[i]],(ii[lrows[i]+1] - ii[lrows[i]])*sizeof(PetscScalar));CHKERRQ(ierr);
1044   }
1045 
1046   /* loop over all elements of off process part of matrix zeroing removed columns*/
1047   if (aij->compressedrow.use) {
1048     m    = aij->compressedrow.nrows;
1049     ii   = aij->compressedrow.i;
1050     ridx = aij->compressedrow.rindex;
1051     for (i=0; i<m; i++) {
1052       n  = ii[i+1] - ii[i];
1053       aj = aij->j + ii[i];
1054       aa = aij->a + ii[i];
1055 
1056       for (j=0; j<n; j++) {
1057         if (PetscAbsScalar(mask[*aj])) {
1058           if (b) bb[*ridx] -= *aa*xx[*aj];
1059           *aa = 0.0;
1060         }
1061         aa++;
1062         aj++;
1063       }
1064       ridx++;
1065     }
1066   } else { /* do not use compressed row format */
1067     m = l->B->rmap->n;
1068     for (i=0; i<m; i++) {
1069       n  = ii[i+1] - ii[i];
1070       aj = aij->j + ii[i];
1071       aa = aij->a + ii[i];
1072       for (j=0; j<n; j++) {
1073         if (PetscAbsScalar(mask[*aj])) {
1074           if (b) bb[i] -= *aa*xx[*aj];
1075           *aa = 0.0;
1076         }
1077         aa++;
1078         aj++;
1079       }
1080     }
1081   }
1082   if (x) {
1083     ierr = VecRestoreArray(b,&bb);CHKERRQ(ierr);
1084     ierr = VecRestoreArrayRead(l->lvec,&xx);CHKERRQ(ierr);
1085   }
1086   ierr = VecRestoreArray(lmask,&mask);CHKERRQ(ierr);
1087   ierr = VecDestroy(&lmask);CHKERRQ(ierr);
1088   ierr = PetscFree(lrows);CHKERRQ(ierr);
1089 
1090   /* wait on sends */
1091   if (nsends) {
1092     ierr = PetscMalloc(nsends*sizeof(MPI_Status),&send_status);CHKERRQ(ierr);
1093     ierr = MPI_Waitall(nsends,send_waits,send_status);CHKERRQ(ierr);
1094     ierr = PetscFree(send_status);CHKERRQ(ierr);
1095   }
1096   ierr = PetscFree(send_waits);CHKERRQ(ierr);
1097   ierr = PetscFree(svalues);CHKERRQ(ierr);
1098   PetscFunctionReturn(0);
1099 }
1100 
1101 #undef __FUNCT__
1102 #define __FUNCT__ "MatMult_MPIAIJ"
1103 PetscErrorCode MatMult_MPIAIJ(Mat A,Vec xx,Vec yy)
1104 {
1105   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
1106   PetscErrorCode ierr;
1107   PetscInt       nt;
1108 
1109   PetscFunctionBegin;
1110   ierr = VecGetLocalSize(xx,&nt);CHKERRQ(ierr);
1111   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);
1112   ierr = VecScatterBegin(a->Mvctx,xx,a->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1113   ierr = (*a->A->ops->mult)(a->A,xx,yy);CHKERRQ(ierr);
1114   ierr = VecScatterEnd(a->Mvctx,xx,a->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1115   ierr = (*a->B->ops->multadd)(a->B,a->lvec,yy,yy);CHKERRQ(ierr);
1116   PetscFunctionReturn(0);
1117 }
1118 
1119 #undef __FUNCT__
1120 #define __FUNCT__ "MatMultDiagonalBlock_MPIAIJ"
1121 PetscErrorCode MatMultDiagonalBlock_MPIAIJ(Mat A,Vec bb,Vec xx)
1122 {
1123   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
1124   PetscErrorCode ierr;
1125 
1126   PetscFunctionBegin;
1127   ierr = MatMultDiagonalBlock(a->A,bb,xx);CHKERRQ(ierr);
1128   PetscFunctionReturn(0);
1129 }
1130 
1131 #undef __FUNCT__
1132 #define __FUNCT__ "MatMultAdd_MPIAIJ"
1133 PetscErrorCode MatMultAdd_MPIAIJ(Mat A,Vec xx,Vec yy,Vec zz)
1134 {
1135   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
1136   PetscErrorCode ierr;
1137 
1138   PetscFunctionBegin;
1139   ierr = VecScatterBegin(a->Mvctx,xx,a->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1140   ierr = (*a->A->ops->multadd)(a->A,xx,yy,zz);CHKERRQ(ierr);
1141   ierr = VecScatterEnd(a->Mvctx,xx,a->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1142   ierr = (*a->B->ops->multadd)(a->B,a->lvec,zz,zz);CHKERRQ(ierr);
1143   PetscFunctionReturn(0);
1144 }
1145 
1146 #undef __FUNCT__
1147 #define __FUNCT__ "MatMultTranspose_MPIAIJ"
1148 PetscErrorCode MatMultTranspose_MPIAIJ(Mat A,Vec xx,Vec yy)
1149 {
1150   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
1151   PetscErrorCode ierr;
1152   PetscBool      merged;
1153 
1154   PetscFunctionBegin;
1155   ierr = VecScatterGetMerged(a->Mvctx,&merged);CHKERRQ(ierr);
1156   /* do nondiagonal part */
1157   ierr = (*a->B->ops->multtranspose)(a->B,xx,a->lvec);CHKERRQ(ierr);
1158   if (!merged) {
1159     /* send it on its way */
1160     ierr = VecScatterBegin(a->Mvctx,a->lvec,yy,ADD_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
1161     /* do local part */
1162     ierr = (*a->A->ops->multtranspose)(a->A,xx,yy);CHKERRQ(ierr);
1163     /* receive remote parts: note this assumes the values are not actually */
1164     /* added in yy until the next line, */
1165     ierr = VecScatterEnd(a->Mvctx,a->lvec,yy,ADD_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
1166   } else {
1167     /* do local part */
1168     ierr = (*a->A->ops->multtranspose)(a->A,xx,yy);CHKERRQ(ierr);
1169     /* send it on its way */
1170     ierr = VecScatterBegin(a->Mvctx,a->lvec,yy,ADD_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
1171     /* values actually were received in the Begin() but we need to call this nop */
1172     ierr = VecScatterEnd(a->Mvctx,a->lvec,yy,ADD_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
1173   }
1174   PetscFunctionReturn(0);
1175 }
1176 
1177 #undef __FUNCT__
1178 #define __FUNCT__ "MatIsTranspose_MPIAIJ"
1179 PetscErrorCode  MatIsTranspose_MPIAIJ(Mat Amat,Mat Bmat,PetscReal tol,PetscBool  *f)
1180 {
1181   MPI_Comm       comm;
1182   Mat_MPIAIJ     *Aij = (Mat_MPIAIJ*) Amat->data, *Bij;
1183   Mat            Adia = Aij->A, Bdia, Aoff,Boff,*Aoffs,*Boffs;
1184   IS             Me,Notme;
1185   PetscErrorCode ierr;
1186   PetscInt       M,N,first,last,*notme,i;
1187   PetscMPIInt    size;
1188 
1189   PetscFunctionBegin;
1190   /* Easy test: symmetric diagonal block */
1191   Bij  = (Mat_MPIAIJ*) Bmat->data; Bdia = Bij->A;
1192   ierr = MatIsTranspose(Adia,Bdia,tol,f);CHKERRQ(ierr);
1193   if (!*f) PetscFunctionReturn(0);
1194   ierr = PetscObjectGetComm((PetscObject)Amat,&comm);CHKERRQ(ierr);
1195   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
1196   if (size == 1) PetscFunctionReturn(0);
1197 
1198   /* Hard test: off-diagonal block. This takes a MatGetSubMatrix. */
1199   ierr = MatGetSize(Amat,&M,&N);CHKERRQ(ierr);
1200   ierr = MatGetOwnershipRange(Amat,&first,&last);CHKERRQ(ierr);
1201   ierr = PetscMalloc((N-last+first)*sizeof(PetscInt),&notme);CHKERRQ(ierr);
1202   for (i=0; i<first; i++) notme[i] = i;
1203   for (i=last; i<M; i++) notme[i-last+first] = i;
1204   ierr = ISCreateGeneral(MPI_COMM_SELF,N-last+first,notme,PETSC_COPY_VALUES,&Notme);CHKERRQ(ierr);
1205   ierr = ISCreateStride(MPI_COMM_SELF,last-first,first,1,&Me);CHKERRQ(ierr);
1206   ierr = MatGetSubMatrices(Amat,1,&Me,&Notme,MAT_INITIAL_MATRIX,&Aoffs);CHKERRQ(ierr);
1207   Aoff = Aoffs[0];
1208   ierr = MatGetSubMatrices(Bmat,1,&Notme,&Me,MAT_INITIAL_MATRIX,&Boffs);CHKERRQ(ierr);
1209   Boff = Boffs[0];
1210   ierr = MatIsTranspose(Aoff,Boff,tol,f);CHKERRQ(ierr);
1211   ierr = MatDestroyMatrices(1,&Aoffs);CHKERRQ(ierr);
1212   ierr = MatDestroyMatrices(1,&Boffs);CHKERRQ(ierr);
1213   ierr = ISDestroy(&Me);CHKERRQ(ierr);
1214   ierr = ISDestroy(&Notme);CHKERRQ(ierr);
1215   ierr = PetscFree(notme);CHKERRQ(ierr);
1216   PetscFunctionReturn(0);
1217 }
1218 
1219 #undef __FUNCT__
1220 #define __FUNCT__ "MatMultTransposeAdd_MPIAIJ"
1221 PetscErrorCode MatMultTransposeAdd_MPIAIJ(Mat A,Vec xx,Vec yy,Vec zz)
1222 {
1223   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
1224   PetscErrorCode ierr;
1225 
1226   PetscFunctionBegin;
1227   /* do nondiagonal part */
1228   ierr = (*a->B->ops->multtranspose)(a->B,xx,a->lvec);CHKERRQ(ierr);
1229   /* send it on its way */
1230   ierr = VecScatterBegin(a->Mvctx,a->lvec,zz,ADD_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
1231   /* do local part */
1232   ierr = (*a->A->ops->multtransposeadd)(a->A,xx,yy,zz);CHKERRQ(ierr);
1233   /* receive remote parts */
1234   ierr = VecScatterEnd(a->Mvctx,a->lvec,zz,ADD_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
1235   PetscFunctionReturn(0);
1236 }
1237 
1238 /*
1239   This only works correctly for square matrices where the subblock A->A is the
1240    diagonal block
1241 */
1242 #undef __FUNCT__
1243 #define __FUNCT__ "MatGetDiagonal_MPIAIJ"
1244 PetscErrorCode MatGetDiagonal_MPIAIJ(Mat A,Vec v)
1245 {
1246   PetscErrorCode ierr;
1247   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
1248 
1249   PetscFunctionBegin;
1250   if (A->rmap->N != A->cmap->N) SETERRQ(PetscObjectComm((PetscObject)A),PETSC_ERR_SUP,"Supports only square matrix where A->A is diag block");
1251   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");
1252   ierr = MatGetDiagonal(a->A,v);CHKERRQ(ierr);
1253   PetscFunctionReturn(0);
1254 }
1255 
1256 #undef __FUNCT__
1257 #define __FUNCT__ "MatScale_MPIAIJ"
1258 PetscErrorCode MatScale_MPIAIJ(Mat A,PetscScalar aa)
1259 {
1260   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
1261   PetscErrorCode ierr;
1262 
1263   PetscFunctionBegin;
1264   ierr = MatScale(a->A,aa);CHKERRQ(ierr);
1265   ierr = MatScale(a->B,aa);CHKERRQ(ierr);
1266   PetscFunctionReturn(0);
1267 }
1268 
1269 #undef __FUNCT__
1270 #define __FUNCT__ "MatDestroy_MPIAIJ"
1271 PetscErrorCode MatDestroy_MPIAIJ(Mat mat)
1272 {
1273   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
1274   PetscErrorCode ierr;
1275 
1276   PetscFunctionBegin;
1277 #if defined(PETSC_USE_LOG)
1278   PetscLogObjectState((PetscObject)mat,"Rows=%D, Cols=%D",mat->rmap->N,mat->cmap->N);
1279 #endif
1280   ierr = MatStashDestroy_Private(&mat->stash);CHKERRQ(ierr);
1281   ierr = VecDestroy(&aij->diag);CHKERRQ(ierr);
1282   ierr = MatDestroy(&aij->A);CHKERRQ(ierr);
1283   ierr = MatDestroy(&aij->B);CHKERRQ(ierr);
1284 #if defined(PETSC_USE_CTABLE)
1285   ierr = PetscTableDestroy(&aij->colmap);CHKERRQ(ierr);
1286 #else
1287   ierr = PetscFree(aij->colmap);CHKERRQ(ierr);
1288 #endif
1289   ierr = PetscFree(aij->garray);CHKERRQ(ierr);
1290   ierr = VecDestroy(&aij->lvec);CHKERRQ(ierr);
1291   ierr = VecScatterDestroy(&aij->Mvctx);CHKERRQ(ierr);
1292   ierr = PetscFree2(aij->rowvalues,aij->rowindices);CHKERRQ(ierr);
1293   ierr = PetscFree(aij->ld);CHKERRQ(ierr);
1294   ierr = PetscFree(mat->data);CHKERRQ(ierr);
1295 
1296   ierr = PetscObjectChangeTypeName((PetscObject)mat,0);CHKERRQ(ierr);
1297   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatStoreValues_C","",NULL);CHKERRQ(ierr);
1298   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatRetrieveValues_C","",NULL);CHKERRQ(ierr);
1299   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatGetDiagonalBlock_C","",NULL);CHKERRQ(ierr);
1300   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatIsTranspose_C","",NULL);CHKERRQ(ierr);
1301   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatMPIAIJSetPreallocation_C","",NULL);CHKERRQ(ierr);
1302   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatMPIAIJSetPreallocationCSR_C","",NULL);CHKERRQ(ierr);
1303   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatDiagonalScaleLocal_C","",NULL);CHKERRQ(ierr);
1304   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatConvert_mpiaij_mpisbaij_C","",NULL);CHKERRQ(ierr);
1305   PetscFunctionReturn(0);
1306 }
1307 
1308 #undef __FUNCT__
1309 #define __FUNCT__ "MatView_MPIAIJ_Binary"
1310 PetscErrorCode MatView_MPIAIJ_Binary(Mat mat,PetscViewer viewer)
1311 {
1312   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
1313   Mat_SeqAIJ     *A   = (Mat_SeqAIJ*)aij->A->data;
1314   Mat_SeqAIJ     *B   = (Mat_SeqAIJ*)aij->B->data;
1315   PetscErrorCode ierr;
1316   PetscMPIInt    rank,size,tag = ((PetscObject)viewer)->tag;
1317   int            fd;
1318   PetscInt       nz,header[4],*row_lengths,*range=0,rlen,i;
1319   PetscInt       nzmax,*column_indices,j,k,col,*garray = aij->garray,cnt,cstart = mat->cmap->rstart,rnz;
1320   PetscScalar    *column_values;
1321   PetscInt       message_count,flowcontrolcount;
1322   FILE           *file;
1323 
1324   PetscFunctionBegin;
1325   ierr = MPI_Comm_rank(PetscObjectComm((PetscObject)mat),&rank);CHKERRQ(ierr);
1326   ierr = MPI_Comm_size(PetscObjectComm((PetscObject)mat),&size);CHKERRQ(ierr);
1327   nz   = A->nz + B->nz;
1328   if (!rank) {
1329     header[0] = MAT_FILE_CLASSID;
1330     header[1] = mat->rmap->N;
1331     header[2] = mat->cmap->N;
1332 
1333     ierr = MPI_Reduce(&nz,&header[3],1,MPIU_INT,MPI_SUM,0,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1334     ierr = PetscViewerBinaryGetDescriptor(viewer,&fd);CHKERRQ(ierr);
1335     ierr = PetscBinaryWrite(fd,header,4,PETSC_INT,PETSC_TRUE);CHKERRQ(ierr);
1336     /* get largest number of rows any processor has */
1337     rlen  = mat->rmap->n;
1338     range = mat->rmap->range;
1339     for (i=1; i<size; i++) rlen = PetscMax(rlen,range[i+1] - range[i]);
1340   } else {
1341     ierr = MPI_Reduce(&nz,0,1,MPIU_INT,MPI_SUM,0,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1342     rlen = mat->rmap->n;
1343   }
1344 
1345   /* load up the local row counts */
1346   ierr = PetscMalloc((rlen+1)*sizeof(PetscInt),&row_lengths);CHKERRQ(ierr);
1347   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];
1348 
1349   /* store the row lengths to the file */
1350   ierr = PetscViewerFlowControlStart(viewer,&message_count,&flowcontrolcount);CHKERRQ(ierr);
1351   if (!rank) {
1352     ierr = PetscBinaryWrite(fd,row_lengths,mat->rmap->n,PETSC_INT,PETSC_TRUE);CHKERRQ(ierr);
1353     for (i=1; i<size; i++) {
1354       ierr = PetscViewerFlowControlStepMaster(viewer,i,&message_count,flowcontrolcount);CHKERRQ(ierr);
1355       rlen = range[i+1] - range[i];
1356       ierr = MPIULong_Recv(row_lengths,rlen,MPIU_INT,i,tag,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1357       ierr = PetscBinaryWrite(fd,row_lengths,rlen,PETSC_INT,PETSC_TRUE);CHKERRQ(ierr);
1358     }
1359     ierr = PetscViewerFlowControlEndMaster(viewer,&message_count);CHKERRQ(ierr);
1360   } else {
1361     ierr = PetscViewerFlowControlStepWorker(viewer,rank,&message_count);CHKERRQ(ierr);
1362     ierr = MPIULong_Send(row_lengths,mat->rmap->n,MPIU_INT,0,tag,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1363     ierr = PetscViewerFlowControlEndWorker(viewer,&message_count);CHKERRQ(ierr);
1364   }
1365   ierr = PetscFree(row_lengths);CHKERRQ(ierr);
1366 
1367   /* load up the local column indices */
1368   nzmax = nz; /* th processor needs space a largest processor needs */
1369   ierr  = MPI_Reduce(&nz,&nzmax,1,MPIU_INT,MPI_MAX,0,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1370   ierr  = PetscMalloc((nzmax+1)*sizeof(PetscInt),&column_indices);CHKERRQ(ierr);
1371   cnt   = 0;
1372   for (i=0; i<mat->rmap->n; i++) {
1373     for (j=B->i[i]; j<B->i[i+1]; j++) {
1374       if ((col = garray[B->j[j]]) > cstart) break;
1375       column_indices[cnt++] = col;
1376     }
1377     for (k=A->i[i]; k<A->i[i+1]; k++) column_indices[cnt++] = A->j[k] + cstart;
1378     for (; j<B->i[i+1]; j++) column_indices[cnt++] = garray[B->j[j]];
1379   }
1380   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);
1381 
1382   /* store the column indices to the file */
1383   ierr = PetscViewerFlowControlStart(viewer,&message_count,&flowcontrolcount);CHKERRQ(ierr);
1384   if (!rank) {
1385     MPI_Status status;
1386     ierr = PetscBinaryWrite(fd,column_indices,nz,PETSC_INT,PETSC_TRUE);CHKERRQ(ierr);
1387     for (i=1; i<size; i++) {
1388       ierr = PetscViewerFlowControlStepMaster(viewer,i,&message_count,flowcontrolcount);CHKERRQ(ierr);
1389       ierr = MPI_Recv(&rnz,1,MPIU_INT,i,tag,PetscObjectComm((PetscObject)mat),&status);CHKERRQ(ierr);
1390       if (rnz > nzmax) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_LIB,"Internal PETSc error: nz = %D nzmax = %D",nz,nzmax);
1391       ierr = MPIULong_Recv(column_indices,rnz,MPIU_INT,i,tag,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1392       ierr = PetscBinaryWrite(fd,column_indices,rnz,PETSC_INT,PETSC_TRUE);CHKERRQ(ierr);
1393     }
1394     ierr = PetscViewerFlowControlEndMaster(viewer,&message_count);CHKERRQ(ierr);
1395   } else {
1396     ierr = PetscViewerFlowControlStepWorker(viewer,rank,&message_count);CHKERRQ(ierr);
1397     ierr = MPI_Send(&nz,1,MPIU_INT,0,tag,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1398     ierr = MPIULong_Send(column_indices,nz,MPIU_INT,0,tag,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1399     ierr = PetscViewerFlowControlEndWorker(viewer,&message_count);CHKERRQ(ierr);
1400   }
1401   ierr = PetscFree(column_indices);CHKERRQ(ierr);
1402 
1403   /* load up the local column values */
1404   ierr = PetscMalloc((nzmax+1)*sizeof(PetscScalar),&column_values);CHKERRQ(ierr);
1405   cnt  = 0;
1406   for (i=0; i<mat->rmap->n; i++) {
1407     for (j=B->i[i]; j<B->i[i+1]; j++) {
1408       if (garray[B->j[j]] > cstart) break;
1409       column_values[cnt++] = B->a[j];
1410     }
1411     for (k=A->i[i]; k<A->i[i+1]; k++) column_values[cnt++] = A->a[k];
1412     for (; j<B->i[i+1]; j++) column_values[cnt++] = B->a[j];
1413   }
1414   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);
1415 
1416   /* store the column values to the file */
1417   ierr = PetscViewerFlowControlStart(viewer,&message_count,&flowcontrolcount);CHKERRQ(ierr);
1418   if (!rank) {
1419     MPI_Status status;
1420     ierr = PetscBinaryWrite(fd,column_values,nz,PETSC_SCALAR,PETSC_TRUE);CHKERRQ(ierr);
1421     for (i=1; i<size; i++) {
1422       ierr = PetscViewerFlowControlStepMaster(viewer,i,&message_count,flowcontrolcount);CHKERRQ(ierr);
1423       ierr = MPI_Recv(&rnz,1,MPIU_INT,i,tag,PetscObjectComm((PetscObject)mat),&status);CHKERRQ(ierr);
1424       if (rnz > nzmax) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_LIB,"Internal PETSc error: nz = %D nzmax = %D",nz,nzmax);
1425       ierr = MPIULong_Recv(column_values,rnz,MPIU_SCALAR,i,tag,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1426       ierr = PetscBinaryWrite(fd,column_values,rnz,PETSC_SCALAR,PETSC_TRUE);CHKERRQ(ierr);
1427     }
1428     ierr = PetscViewerFlowControlEndMaster(viewer,&message_count);CHKERRQ(ierr);
1429   } else {
1430     ierr = PetscViewerFlowControlStepWorker(viewer,rank,&message_count);CHKERRQ(ierr);
1431     ierr = MPI_Send(&nz,1,MPIU_INT,0,tag,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1432     ierr = MPIULong_Send(column_values,nz,MPIU_SCALAR,0,tag,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
1433     ierr = PetscViewerFlowControlEndWorker(viewer,&message_count);CHKERRQ(ierr);
1434   }
1435   ierr = PetscFree(column_values);CHKERRQ(ierr);
1436 
1437   ierr = PetscViewerBinaryGetInfoPointer(viewer,&file);CHKERRQ(ierr);
1438   if (file) fprintf(file,"-matload_block_size %d\n",(int)mat->rmap->bs);
1439   PetscFunctionReturn(0);
1440 }
1441 
1442 #include <petscdraw.h>
1443 #undef __FUNCT__
1444 #define __FUNCT__ "MatView_MPIAIJ_ASCIIorDraworSocket"
1445 PetscErrorCode MatView_MPIAIJ_ASCIIorDraworSocket(Mat mat,PetscViewer viewer)
1446 {
1447   Mat_MPIAIJ        *aij = (Mat_MPIAIJ*)mat->data;
1448   PetscErrorCode    ierr;
1449   PetscMPIInt       rank = aij->rank,size = aij->size;
1450   PetscBool         isdraw,iascii,isbinary;
1451   PetscViewer       sviewer;
1452   PetscViewerFormat format;
1453 
1454   PetscFunctionBegin;
1455   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERDRAW,&isdraw);CHKERRQ(ierr);
1456   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERASCII,&iascii);CHKERRQ(ierr);
1457   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERBINARY,&isbinary);CHKERRQ(ierr);
1458   if (iascii) {
1459     ierr = PetscViewerGetFormat(viewer,&format);CHKERRQ(ierr);
1460     if (format == PETSC_VIEWER_ASCII_INFO_DETAIL) {
1461       MatInfo   info;
1462       PetscBool inodes;
1463 
1464       ierr = MPI_Comm_rank(PetscObjectComm((PetscObject)mat),&rank);CHKERRQ(ierr);
1465       ierr = MatGetInfo(mat,MAT_LOCAL,&info);CHKERRQ(ierr);
1466       ierr = MatInodeGetInodeSizes(aij->A,NULL,(PetscInt**)&inodes,NULL);CHKERRQ(ierr);
1467       ierr = PetscViewerASCIISynchronizedAllow(viewer,PETSC_TRUE);CHKERRQ(ierr);
1468       if (!inodes) {
1469         ierr = PetscViewerASCIISynchronizedPrintf(viewer,"[%d] Local rows %D nz %D nz alloced %D mem %D, not using I-node routines\n",
1470                                                   rank,mat->rmap->n,(PetscInt)info.nz_used,(PetscInt)info.nz_allocated,(PetscInt)info.memory);CHKERRQ(ierr);
1471       } else {
1472         ierr = PetscViewerASCIISynchronizedPrintf(viewer,"[%d] Local rows %D nz %D nz alloced %D mem %D, using I-node routines\n",
1473                                                   rank,mat->rmap->n,(PetscInt)info.nz_used,(PetscInt)info.nz_allocated,(PetscInt)info.memory);CHKERRQ(ierr);
1474       }
1475       ierr = MatGetInfo(aij->A,MAT_LOCAL,&info);CHKERRQ(ierr);
1476       ierr = PetscViewerASCIISynchronizedPrintf(viewer,"[%d] on-diagonal part: nz %D \n",rank,(PetscInt)info.nz_used);CHKERRQ(ierr);
1477       ierr = MatGetInfo(aij->B,MAT_LOCAL,&info);CHKERRQ(ierr);
1478       ierr = PetscViewerASCIISynchronizedPrintf(viewer,"[%d] off-diagonal part: nz %D \n",rank,(PetscInt)info.nz_used);CHKERRQ(ierr);
1479       ierr = PetscViewerFlush(viewer);CHKERRQ(ierr);
1480       ierr = PetscViewerASCIISynchronizedAllow(viewer,PETSC_FALSE);CHKERRQ(ierr);
1481       ierr = PetscViewerASCIIPrintf(viewer,"Information on VecScatter used in matrix-vector product: \n");CHKERRQ(ierr);
1482       ierr = VecScatterView(aij->Mvctx,viewer);CHKERRQ(ierr);
1483       PetscFunctionReturn(0);
1484     } else if (format == PETSC_VIEWER_ASCII_INFO) {
1485       PetscInt inodecount,inodelimit,*inodes;
1486       ierr = MatInodeGetInodeSizes(aij->A,&inodecount,&inodes,&inodelimit);CHKERRQ(ierr);
1487       if (inodes) {
1488         ierr = PetscViewerASCIIPrintf(viewer,"using I-node (on process 0) routines: found %D nodes, limit used is %D\n",inodecount,inodelimit);CHKERRQ(ierr);
1489       } else {
1490         ierr = PetscViewerASCIIPrintf(viewer,"not using I-node (on process 0) routines\n");CHKERRQ(ierr);
1491       }
1492       PetscFunctionReturn(0);
1493     } else if (format == PETSC_VIEWER_ASCII_FACTOR_INFO) {
1494       PetscFunctionReturn(0);
1495     }
1496   } else if (isbinary) {
1497     if (size == 1) {
1498       ierr = PetscObjectSetName((PetscObject)aij->A,((PetscObject)mat)->name);CHKERRQ(ierr);
1499       ierr = MatView(aij->A,viewer);CHKERRQ(ierr);
1500     } else {
1501       ierr = MatView_MPIAIJ_Binary(mat,viewer);CHKERRQ(ierr);
1502     }
1503     PetscFunctionReturn(0);
1504   } else if (isdraw) {
1505     PetscDraw draw;
1506     PetscBool isnull;
1507     ierr = PetscViewerDrawGetDraw(viewer,0,&draw);CHKERRQ(ierr);
1508     ierr = PetscDrawIsNull(draw,&isnull);CHKERRQ(ierr); if (isnull) PetscFunctionReturn(0);
1509   }
1510 
1511   if (size == 1) {
1512     ierr = PetscObjectSetName((PetscObject)aij->A,((PetscObject)mat)->name);CHKERRQ(ierr);
1513     ierr = MatView(aij->A,viewer);CHKERRQ(ierr);
1514   } else {
1515     /* assemble the entire matrix onto first processor. */
1516     Mat        A;
1517     Mat_SeqAIJ *Aloc;
1518     PetscInt   M = mat->rmap->N,N = mat->cmap->N,m,*ai,*aj,row,*cols,i,*ct;
1519     MatScalar  *a;
1520 
1521     if (mat->rmap->N > 1024) {
1522       PetscBool flg = PETSC_FALSE;
1523 
1524       ierr = PetscOptionsGetBool(((PetscObject) mat)->prefix, "-mat_ascii_output_large", &flg,NULL);CHKERRQ(ierr);
1525       if (!flg) SETERRQ(PetscObjectComm((PetscObject)mat),PETSC_ERR_ARG_OUTOFRANGE,"ASCII matrix output not allowed for matrices with more than 1024 rows, use binary format instead.\nYou can override this restriction using -mat_ascii_output_large.");
1526     }
1527 
1528     ierr = MatCreate(PetscObjectComm((PetscObject)mat),&A);CHKERRQ(ierr);
1529     if (!rank) {
1530       ierr = MatSetSizes(A,M,N,M,N);CHKERRQ(ierr);
1531     } else {
1532       ierr = MatSetSizes(A,0,0,M,N);CHKERRQ(ierr);
1533     }
1534     /* This is just a temporary matrix, so explicitly using MATMPIAIJ is probably best */
1535     ierr = MatSetType(A,MATMPIAIJ);CHKERRQ(ierr);
1536     ierr = MatMPIAIJSetPreallocation(A,0,NULL,0,NULL);CHKERRQ(ierr);
1537     ierr = MatSetOption(A,MAT_NEW_NONZERO_LOCATION_ERR,PETSC_FALSE);CHKERRQ(ierr);
1538     ierr = PetscLogObjectParent(mat,A);CHKERRQ(ierr);
1539 
1540     /* copy over the A part */
1541     Aloc = (Mat_SeqAIJ*)aij->A->data;
1542     m    = aij->A->rmap->n; ai = Aloc->i; aj = Aloc->j; a = Aloc->a;
1543     row  = mat->rmap->rstart;
1544     for (i=0; i<ai[m]; i++) aj[i] += mat->cmap->rstart;
1545     for (i=0; i<m; i++) {
1546       ierr = MatSetValues(A,1,&row,ai[i+1]-ai[i],aj,a,INSERT_VALUES);CHKERRQ(ierr);
1547       row++;
1548       a += ai[i+1]-ai[i]; aj += ai[i+1]-ai[i];
1549     }
1550     aj = Aloc->j;
1551     for (i=0; i<ai[m]; i++) aj[i] -= mat->cmap->rstart;
1552 
1553     /* copy over the B part */
1554     Aloc = (Mat_SeqAIJ*)aij->B->data;
1555     m    = aij->B->rmap->n;  ai = Aloc->i; aj = Aloc->j; a = Aloc->a;
1556     row  = mat->rmap->rstart;
1557     ierr = PetscMalloc((ai[m]+1)*sizeof(PetscInt),&cols);CHKERRQ(ierr);
1558     ct   = cols;
1559     for (i=0; i<ai[m]; i++) cols[i] = aij->garray[aj[i]];
1560     for (i=0; i<m; i++) {
1561       ierr = MatSetValues(A,1,&row,ai[i+1]-ai[i],cols,a,INSERT_VALUES);CHKERRQ(ierr);
1562       row++;
1563       a += ai[i+1]-ai[i]; cols += ai[i+1]-ai[i];
1564     }
1565     ierr = PetscFree(ct);CHKERRQ(ierr);
1566     ierr = MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
1567     ierr = MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
1568     /*
1569        Everyone has to call to draw the matrix since the graphics waits are
1570        synchronized across all processors that share the PetscDraw object
1571     */
1572     ierr = PetscViewerGetSingleton(viewer,&sviewer);CHKERRQ(ierr);
1573     if (!rank) {
1574       ierr = PetscObjectSetName((PetscObject)((Mat_MPIAIJ*)(A->data))->A,((PetscObject)mat)->name);CHKERRQ(ierr);
1575       /* Set the type name to MATMPIAIJ so that the correct type can be printed out by PetscObjectPrintClassNamePrefixType() in MatView_SeqAIJ_ASCII()*/
1576       PetscStrcpy(((PetscObject)((Mat_MPIAIJ*)(A->data))->A)->type_name,MATMPIAIJ);
1577       ierr = MatView(((Mat_MPIAIJ*)(A->data))->A,sviewer);CHKERRQ(ierr);
1578     }
1579     ierr = PetscViewerRestoreSingleton(viewer,&sviewer);CHKERRQ(ierr);
1580     ierr = MatDestroy(&A);CHKERRQ(ierr);
1581   }
1582   PetscFunctionReturn(0);
1583 }
1584 
1585 #undef __FUNCT__
1586 #define __FUNCT__ "MatView_MPIAIJ"
1587 PetscErrorCode MatView_MPIAIJ(Mat mat,PetscViewer viewer)
1588 {
1589   PetscErrorCode ierr;
1590   PetscBool      iascii,isdraw,issocket,isbinary;
1591 
1592   PetscFunctionBegin;
1593   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERASCII,&iascii);CHKERRQ(ierr);
1594   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERDRAW,&isdraw);CHKERRQ(ierr);
1595   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERBINARY,&isbinary);CHKERRQ(ierr);
1596   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERSOCKET,&issocket);CHKERRQ(ierr);
1597   if (iascii || isdraw || isbinary || issocket) {
1598     ierr = MatView_MPIAIJ_ASCIIorDraworSocket(mat,viewer);CHKERRQ(ierr);
1599   }
1600   PetscFunctionReturn(0);
1601 }
1602 
1603 #undef __FUNCT__
1604 #define __FUNCT__ "MatSOR_MPIAIJ"
1605 PetscErrorCode MatSOR_MPIAIJ(Mat matin,Vec bb,PetscReal omega,MatSORType flag,PetscReal fshift,PetscInt its,PetscInt lits,Vec xx)
1606 {
1607   Mat_MPIAIJ     *mat = (Mat_MPIAIJ*)matin->data;
1608   PetscErrorCode ierr;
1609   Vec            bb1 = 0;
1610   PetscBool      hasop;
1611 
1612   PetscFunctionBegin;
1613   if (flag == SOR_APPLY_UPPER) {
1614     ierr = (*mat->A->ops->sor)(mat->A,bb,omega,flag,fshift,lits,1,xx);CHKERRQ(ierr);
1615     PetscFunctionReturn(0);
1616   }
1617 
1618   if (its > 1 || ~flag & SOR_ZERO_INITIAL_GUESS || flag & SOR_EISENSTAT) {
1619     ierr = VecDuplicate(bb,&bb1);CHKERRQ(ierr);
1620   }
1621 
1622   if ((flag & SOR_LOCAL_SYMMETRIC_SWEEP) == SOR_LOCAL_SYMMETRIC_SWEEP) {
1623     if (flag & SOR_ZERO_INITIAL_GUESS) {
1624       ierr = (*mat->A->ops->sor)(mat->A,bb,omega,flag,fshift,lits,1,xx);CHKERRQ(ierr);
1625       its--;
1626     }
1627 
1628     while (its--) {
1629       ierr = VecScatterBegin(mat->Mvctx,xx,mat->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1630       ierr = VecScatterEnd(mat->Mvctx,xx,mat->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1631 
1632       /* update rhs: bb1 = bb - B*x */
1633       ierr = VecScale(mat->lvec,-1.0);CHKERRQ(ierr);
1634       ierr = (*mat->B->ops->multadd)(mat->B,mat->lvec,bb,bb1);CHKERRQ(ierr);
1635 
1636       /* local sweep */
1637       ierr = (*mat->A->ops->sor)(mat->A,bb1,omega,SOR_SYMMETRIC_SWEEP,fshift,lits,1,xx);CHKERRQ(ierr);
1638     }
1639   } else if (flag & SOR_LOCAL_FORWARD_SWEEP) {
1640     if (flag & SOR_ZERO_INITIAL_GUESS) {
1641       ierr = (*mat->A->ops->sor)(mat->A,bb,omega,flag,fshift,lits,1,xx);CHKERRQ(ierr);
1642       its--;
1643     }
1644     while (its--) {
1645       ierr = VecScatterBegin(mat->Mvctx,xx,mat->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1646       ierr = VecScatterEnd(mat->Mvctx,xx,mat->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1647 
1648       /* update rhs: bb1 = bb - B*x */
1649       ierr = VecScale(mat->lvec,-1.0);CHKERRQ(ierr);
1650       ierr = (*mat->B->ops->multadd)(mat->B,mat->lvec,bb,bb1);CHKERRQ(ierr);
1651 
1652       /* local sweep */
1653       ierr = (*mat->A->ops->sor)(mat->A,bb1,omega,SOR_FORWARD_SWEEP,fshift,lits,1,xx);CHKERRQ(ierr);
1654     }
1655   } else if (flag & SOR_LOCAL_BACKWARD_SWEEP) {
1656     if (flag & SOR_ZERO_INITIAL_GUESS) {
1657       ierr = (*mat->A->ops->sor)(mat->A,bb,omega,flag,fshift,lits,1,xx);CHKERRQ(ierr);
1658       its--;
1659     }
1660     while (its--) {
1661       ierr = VecScatterBegin(mat->Mvctx,xx,mat->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1662       ierr = VecScatterEnd(mat->Mvctx,xx,mat->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1663 
1664       /* update rhs: bb1 = bb - B*x */
1665       ierr = VecScale(mat->lvec,-1.0);CHKERRQ(ierr);
1666       ierr = (*mat->B->ops->multadd)(mat->B,mat->lvec,bb,bb1);CHKERRQ(ierr);
1667 
1668       /* local sweep */
1669       ierr = (*mat->A->ops->sor)(mat->A,bb1,omega,SOR_BACKWARD_SWEEP,fshift,lits,1,xx);CHKERRQ(ierr);
1670     }
1671   } else if (flag & SOR_EISENSTAT) {
1672     Vec xx1;
1673 
1674     ierr = VecDuplicate(bb,&xx1);CHKERRQ(ierr);
1675     ierr = (*mat->A->ops->sor)(mat->A,bb,omega,(MatSORType)(SOR_ZERO_INITIAL_GUESS | SOR_LOCAL_BACKWARD_SWEEP),fshift,lits,1,xx);CHKERRQ(ierr);
1676 
1677     ierr = VecScatterBegin(mat->Mvctx,xx,mat->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1678     ierr = VecScatterEnd(mat->Mvctx,xx,mat->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1679     if (!mat->diag) {
1680       ierr = MatGetVecs(matin,&mat->diag,NULL);CHKERRQ(ierr);
1681       ierr = MatGetDiagonal(matin,mat->diag);CHKERRQ(ierr);
1682     }
1683     ierr = MatHasOperation(matin,MATOP_MULT_DIAGONAL_BLOCK,&hasop);CHKERRQ(ierr);
1684     if (hasop) {
1685       ierr = MatMultDiagonalBlock(matin,xx,bb1);CHKERRQ(ierr);
1686     } else {
1687       ierr = VecPointwiseMult(bb1,mat->diag,xx);CHKERRQ(ierr);
1688     }
1689     ierr = VecAYPX(bb1,(omega-2.0)/omega,bb);CHKERRQ(ierr);
1690 
1691     ierr = MatMultAdd(mat->B,mat->lvec,bb1,bb1);CHKERRQ(ierr);
1692 
1693     /* local sweep */
1694     ierr = (*mat->A->ops->sor)(mat->A,bb1,omega,(MatSORType)(SOR_ZERO_INITIAL_GUESS | SOR_LOCAL_FORWARD_SWEEP),fshift,lits,1,xx1);CHKERRQ(ierr);
1695     ierr = VecAXPY(xx,1.0,xx1);CHKERRQ(ierr);
1696     ierr = VecDestroy(&xx1);CHKERRQ(ierr);
1697   } else SETERRQ(PetscObjectComm((PetscObject)matin),PETSC_ERR_SUP,"Parallel SOR not supported");
1698 
1699   ierr = VecDestroy(&bb1);CHKERRQ(ierr);
1700   PetscFunctionReturn(0);
1701 }
1702 
1703 #undef __FUNCT__
1704 #define __FUNCT__ "MatPermute_MPIAIJ"
1705 PetscErrorCode MatPermute_MPIAIJ(Mat A,IS rowp,IS colp,Mat *B)
1706 {
1707   Mat            aA,aB,Aperm;
1708   const PetscInt *rwant,*cwant,*gcols,*ai,*bi,*aj,*bj;
1709   PetscScalar    *aa,*ba;
1710   PetscInt       i,j,m,n,ng,anz,bnz,*dnnz,*onnz,*tdnnz,*tonnz,*rdest,*cdest,*work,*gcdest;
1711   PetscSF        rowsf,sf;
1712   IS             parcolp = NULL;
1713   PetscBool      done;
1714   PetscErrorCode ierr;
1715 
1716   PetscFunctionBegin;
1717   ierr = MatGetLocalSize(A,&m,&n);CHKERRQ(ierr);
1718   ierr = ISGetIndices(rowp,&rwant);CHKERRQ(ierr);
1719   ierr = ISGetIndices(colp,&cwant);CHKERRQ(ierr);
1720   ierr = PetscMalloc3(PetscMax(m,n),PetscInt,&work,m,PetscInt,&rdest,n,PetscInt,&cdest);CHKERRQ(ierr);
1721 
1722   /* Invert row permutation to find out where my rows should go */
1723   ierr = PetscSFCreate(PetscObjectComm((PetscObject)A),&rowsf);CHKERRQ(ierr);
1724   ierr = PetscSFSetGraphLayout(rowsf,A->rmap,A->rmap->n,NULL,PETSC_OWN_POINTER,rwant);CHKERRQ(ierr);
1725   ierr = PetscSFSetFromOptions(rowsf);CHKERRQ(ierr);
1726   for (i=0; i<m; i++) work[i] = A->rmap->rstart + i;
1727   ierr = PetscSFReduceBegin(rowsf,MPIU_INT,work,rdest,MPI_REPLACE);CHKERRQ(ierr);
1728   ierr = PetscSFReduceEnd(rowsf,MPIU_INT,work,rdest,MPI_REPLACE);CHKERRQ(ierr);
1729 
1730   /* Invert column permutation to find out where my columns should go */
1731   ierr = PetscSFCreate(PetscObjectComm((PetscObject)A),&sf);CHKERRQ(ierr);
1732   ierr = PetscSFSetGraphLayout(sf,A->cmap,A->cmap->n,NULL,PETSC_OWN_POINTER,cwant);CHKERRQ(ierr);
1733   ierr = PetscSFSetFromOptions(sf);CHKERRQ(ierr);
1734   for (i=0; i<n; i++) work[i] = A->cmap->rstart + i;
1735   ierr = PetscSFReduceBegin(sf,MPIU_INT,work,cdest,MPI_REPLACE);CHKERRQ(ierr);
1736   ierr = PetscSFReduceEnd(sf,MPIU_INT,work,cdest,MPI_REPLACE);CHKERRQ(ierr);
1737   ierr = PetscSFDestroy(&sf);CHKERRQ(ierr);
1738 
1739   ierr = ISRestoreIndices(rowp,&rwant);CHKERRQ(ierr);
1740   ierr = ISRestoreIndices(colp,&cwant);CHKERRQ(ierr);
1741   ierr = MatMPIAIJGetSeqAIJ(A,&aA,&aB,&gcols);CHKERRQ(ierr);
1742 
1743   /* Find out where my gcols should go */
1744   ierr = MatGetSize(aB,NULL,&ng);CHKERRQ(ierr);
1745   ierr = PetscMalloc(ng*sizeof(PetscInt),&gcdest);CHKERRQ(ierr);
1746   ierr = PetscSFCreate(PetscObjectComm((PetscObject)A),&sf);CHKERRQ(ierr);
1747   ierr = PetscSFSetGraphLayout(sf,A->cmap,ng,NULL,PETSC_OWN_POINTER,gcols);CHKERRQ(ierr);
1748   ierr = PetscSFSetFromOptions(sf);CHKERRQ(ierr);
1749   ierr = PetscSFBcastBegin(sf,MPIU_INT,cdest,gcdest);CHKERRQ(ierr);
1750   ierr = PetscSFBcastEnd(sf,MPIU_INT,cdest,gcdest);CHKERRQ(ierr);
1751   ierr = PetscSFDestroy(&sf);CHKERRQ(ierr);
1752 
1753   ierr = PetscMalloc4(m,PetscInt,&dnnz,m,PetscInt,&onnz,m,PetscInt,&tdnnz,m,PetscInt,&tonnz);CHKERRQ(ierr);
1754   ierr = PetscMemzero(dnnz,m*sizeof(PetscInt));CHKERRQ(ierr);
1755   ierr = PetscMemzero(onnz,m*sizeof(PetscInt));CHKERRQ(ierr);
1756   ierr = MatGetRowIJ(aA,0,PETSC_FALSE,PETSC_FALSE,&anz,&ai,&aj,&done);CHKERRQ(ierr);
1757   ierr = MatGetRowIJ(aB,0,PETSC_FALSE,PETSC_FALSE,&bnz,&bi,&bj,&done);CHKERRQ(ierr);
1758   for (i=0; i<m; i++) {
1759     PetscInt row = rdest[i],rowner;
1760     ierr = PetscLayoutFindOwner(A->rmap,row,&rowner);CHKERRQ(ierr);
1761     for (j=ai[i]; j<ai[i+1]; j++) {
1762       PetscInt cowner,col = cdest[aj[j]];
1763       ierr = PetscLayoutFindOwner(A->cmap,col,&cowner);CHKERRQ(ierr); /* Could build an index for the columns to eliminate this search */
1764       if (rowner == cowner) dnnz[i]++;
1765       else onnz[i]++;
1766     }
1767     for (j=bi[i]; j<bi[i+1]; j++) {
1768       PetscInt cowner,col = gcdest[bj[j]];
1769       ierr = PetscLayoutFindOwner(A->cmap,col,&cowner);CHKERRQ(ierr);
1770       if (rowner == cowner) dnnz[i]++;
1771       else onnz[i]++;
1772     }
1773   }
1774   ierr = PetscMemzero(tdnnz,m*sizeof(PetscInt));CHKERRQ(ierr);
1775   ierr = PetscMemzero(tonnz,m*sizeof(PetscInt));CHKERRQ(ierr);
1776   ierr = PetscSFBcastBegin(rowsf,MPIU_INT,dnnz,tdnnz);CHKERRQ(ierr);
1777   ierr = PetscSFBcastEnd(rowsf,MPIU_INT,dnnz,tdnnz);CHKERRQ(ierr);
1778   ierr = PetscSFBcastBegin(rowsf,MPIU_INT,onnz,tonnz);CHKERRQ(ierr);
1779   ierr = PetscSFBcastEnd(rowsf,MPIU_INT,onnz,tonnz);CHKERRQ(ierr);
1780   ierr = PetscSFDestroy(&rowsf);CHKERRQ(ierr);
1781 
1782   ierr = MatCreateAIJ(PetscObjectComm((PetscObject)A),A->rmap->n,A->cmap->n,A->rmap->N,A->cmap->N,0,tdnnz,0,tonnz,&Aperm);CHKERRQ(ierr);
1783   ierr = MatSeqAIJGetArray(aA,&aa);CHKERRQ(ierr);
1784   ierr = MatSeqAIJGetArray(aB,&ba);CHKERRQ(ierr);
1785   for (i=0; i<m; i++) {
1786     PetscInt *acols = dnnz,*bcols = onnz; /* Repurpose now-unneeded arrays */
1787     PetscInt rowlen;
1788     rowlen = ai[i+1] - ai[i];
1789     for (j=0; j<rowlen; j++) acols[j] = cdest[aj[ai[i]+j]];
1790     ierr   = MatSetValues(Aperm,1,&rdest[i],rowlen,acols,aa+ai[i],INSERT_VALUES);CHKERRQ(ierr);
1791     rowlen = bi[i+1] - bi[i];
1792     for (j=0; j<rowlen; j++) bcols[j] = gcdest[bj[bi[i]+j]];
1793     ierr = MatSetValues(Aperm,1,&rdest[i],rowlen,bcols,ba+bi[i],INSERT_VALUES);CHKERRQ(ierr);
1794   }
1795   ierr = MatAssemblyBegin(Aperm,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
1796   ierr = MatAssemblyEnd(Aperm,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
1797   ierr = MatRestoreRowIJ(aA,0,PETSC_FALSE,PETSC_FALSE,&anz,&ai,&aj,&done);CHKERRQ(ierr);
1798   ierr = MatRestoreRowIJ(aB,0,PETSC_FALSE,PETSC_FALSE,&bnz,&bi,&bj,&done);CHKERRQ(ierr);
1799   ierr = MatSeqAIJRestoreArray(aA,&aa);CHKERRQ(ierr);
1800   ierr = MatSeqAIJRestoreArray(aB,&ba);CHKERRQ(ierr);
1801   ierr = PetscFree4(dnnz,onnz,tdnnz,tonnz);CHKERRQ(ierr);
1802   ierr = PetscFree3(work,rdest,cdest);CHKERRQ(ierr);
1803   ierr = PetscFree(gcdest);CHKERRQ(ierr);
1804   if (parcolp) {ierr = ISDestroy(&colp);CHKERRQ(ierr);}
1805   *B = Aperm;
1806   PetscFunctionReturn(0);
1807 }
1808 
1809 #undef __FUNCT__
1810 #define __FUNCT__ "MatGetInfo_MPIAIJ"
1811 PetscErrorCode MatGetInfo_MPIAIJ(Mat matin,MatInfoType flag,MatInfo *info)
1812 {
1813   Mat_MPIAIJ     *mat = (Mat_MPIAIJ*)matin->data;
1814   Mat            A    = mat->A,B = mat->B;
1815   PetscErrorCode ierr;
1816   PetscReal      isend[5],irecv[5];
1817 
1818   PetscFunctionBegin;
1819   info->block_size = 1.0;
1820   ierr             = MatGetInfo(A,MAT_LOCAL,info);CHKERRQ(ierr);
1821 
1822   isend[0] = info->nz_used; isend[1] = info->nz_allocated; isend[2] = info->nz_unneeded;
1823   isend[3] = info->memory;  isend[4] = info->mallocs;
1824 
1825   ierr = MatGetInfo(B,MAT_LOCAL,info);CHKERRQ(ierr);
1826 
1827   isend[0] += info->nz_used; isend[1] += info->nz_allocated; isend[2] += info->nz_unneeded;
1828   isend[3] += info->memory;  isend[4] += info->mallocs;
1829   if (flag == MAT_LOCAL) {
1830     info->nz_used      = isend[0];
1831     info->nz_allocated = isend[1];
1832     info->nz_unneeded  = isend[2];
1833     info->memory       = isend[3];
1834     info->mallocs      = isend[4];
1835   } else if (flag == MAT_GLOBAL_MAX) {
1836     ierr = MPI_Allreduce(isend,irecv,5,MPIU_REAL,MPIU_MAX,PetscObjectComm((PetscObject)matin));CHKERRQ(ierr);
1837 
1838     info->nz_used      = irecv[0];
1839     info->nz_allocated = irecv[1];
1840     info->nz_unneeded  = irecv[2];
1841     info->memory       = irecv[3];
1842     info->mallocs      = irecv[4];
1843   } else if (flag == MAT_GLOBAL_SUM) {
1844     ierr = MPI_Allreduce(isend,irecv,5,MPIU_REAL,MPIU_SUM,PetscObjectComm((PetscObject)matin));CHKERRQ(ierr);
1845 
1846     info->nz_used      = irecv[0];
1847     info->nz_allocated = irecv[1];
1848     info->nz_unneeded  = irecv[2];
1849     info->memory       = irecv[3];
1850     info->mallocs      = irecv[4];
1851   }
1852   info->fill_ratio_given  = 0; /* no parallel LU/ILU/Cholesky */
1853   info->fill_ratio_needed = 0;
1854   info->factor_mallocs    = 0;
1855   PetscFunctionReturn(0);
1856 }
1857 
1858 #undef __FUNCT__
1859 #define __FUNCT__ "MatSetOption_MPIAIJ"
1860 PetscErrorCode MatSetOption_MPIAIJ(Mat A,MatOption op,PetscBool flg)
1861 {
1862   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
1863   PetscErrorCode ierr;
1864 
1865   PetscFunctionBegin;
1866   switch (op) {
1867   case MAT_NEW_NONZERO_LOCATIONS:
1868   case MAT_NEW_NONZERO_ALLOCATION_ERR:
1869   case MAT_UNUSED_NONZERO_LOCATION_ERR:
1870   case MAT_KEEP_NONZERO_PATTERN:
1871   case MAT_NEW_NONZERO_LOCATION_ERR:
1872   case MAT_USE_INODES:
1873   case MAT_IGNORE_ZERO_ENTRIES:
1874     MatCheckPreallocated(A,1);
1875     ierr = MatSetOption(a->A,op,flg);CHKERRQ(ierr);
1876     ierr = MatSetOption(a->B,op,flg);CHKERRQ(ierr);
1877     break;
1878   case MAT_ROW_ORIENTED:
1879     a->roworiented = flg;
1880 
1881     ierr = MatSetOption(a->A,op,flg);CHKERRQ(ierr);
1882     ierr = MatSetOption(a->B,op,flg);CHKERRQ(ierr);
1883     break;
1884   case MAT_NEW_DIAGONALS:
1885     ierr = PetscInfo1(A,"Option %s ignored\n",MatOptions[op]);CHKERRQ(ierr);
1886     break;
1887   case MAT_IGNORE_OFF_PROC_ENTRIES:
1888     a->donotstash = flg;
1889     break;
1890   case MAT_SPD:
1891     A->spd_set = PETSC_TRUE;
1892     A->spd     = flg;
1893     if (flg) {
1894       A->symmetric                  = PETSC_TRUE;
1895       A->structurally_symmetric     = PETSC_TRUE;
1896       A->symmetric_set              = PETSC_TRUE;
1897       A->structurally_symmetric_set = PETSC_TRUE;
1898     }
1899     break;
1900   case MAT_SYMMETRIC:
1901     ierr = MatSetOption(a->A,op,flg);CHKERRQ(ierr);
1902     break;
1903   case MAT_STRUCTURALLY_SYMMETRIC:
1904     ierr = MatSetOption(a->A,op,flg);CHKERRQ(ierr);
1905     break;
1906   case MAT_HERMITIAN:
1907     ierr = MatSetOption(a->A,op,flg);CHKERRQ(ierr);
1908     break;
1909   case MAT_SYMMETRY_ETERNAL:
1910     ierr = MatSetOption(a->A,op,flg);CHKERRQ(ierr);
1911     break;
1912   default:
1913     SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_SUP,"unknown option %d",op);
1914   }
1915   PetscFunctionReturn(0);
1916 }
1917 
1918 #undef __FUNCT__
1919 #define __FUNCT__ "MatGetRow_MPIAIJ"
1920 PetscErrorCode MatGetRow_MPIAIJ(Mat matin,PetscInt row,PetscInt *nz,PetscInt **idx,PetscScalar **v)
1921 {
1922   Mat_MPIAIJ     *mat = (Mat_MPIAIJ*)matin->data;
1923   PetscScalar    *vworkA,*vworkB,**pvA,**pvB,*v_p;
1924   PetscErrorCode ierr;
1925   PetscInt       i,*cworkA,*cworkB,**pcA,**pcB,cstart = matin->cmap->rstart;
1926   PetscInt       nztot,nzA,nzB,lrow,rstart = matin->rmap->rstart,rend = matin->rmap->rend;
1927   PetscInt       *cmap,*idx_p;
1928 
1929   PetscFunctionBegin;
1930   if (mat->getrowactive) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"Already active");
1931   mat->getrowactive = PETSC_TRUE;
1932 
1933   if (!mat->rowvalues && (idx || v)) {
1934     /*
1935         allocate enough space to hold information from the longest row.
1936     */
1937     Mat_SeqAIJ *Aa = (Mat_SeqAIJ*)mat->A->data,*Ba = (Mat_SeqAIJ*)mat->B->data;
1938     PetscInt   max = 1,tmp;
1939     for (i=0; i<matin->rmap->n; i++) {
1940       tmp = Aa->i[i+1] - Aa->i[i] + Ba->i[i+1] - Ba->i[i];
1941       if (max < tmp) max = tmp;
1942     }
1943     ierr = PetscMalloc2(max,PetscScalar,&mat->rowvalues,max,PetscInt,&mat->rowindices);CHKERRQ(ierr);
1944   }
1945 
1946   if (row < rstart || row >= rend) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Only local rows");
1947   lrow = row - rstart;
1948 
1949   pvA = &vworkA; pcA = &cworkA; pvB = &vworkB; pcB = &cworkB;
1950   if (!v)   {pvA = 0; pvB = 0;}
1951   if (!idx) {pcA = 0; if (!v) pcB = 0;}
1952   ierr  = (*mat->A->ops->getrow)(mat->A,lrow,&nzA,pcA,pvA);CHKERRQ(ierr);
1953   ierr  = (*mat->B->ops->getrow)(mat->B,lrow,&nzB,pcB,pvB);CHKERRQ(ierr);
1954   nztot = nzA + nzB;
1955 
1956   cmap = mat->garray;
1957   if (v  || idx) {
1958     if (nztot) {
1959       /* Sort by increasing column numbers, assuming A and B already sorted */
1960       PetscInt imark = -1;
1961       if (v) {
1962         *v = v_p = mat->rowvalues;
1963         for (i=0; i<nzB; i++) {
1964           if (cmap[cworkB[i]] < cstart) v_p[i] = vworkB[i];
1965           else break;
1966         }
1967         imark = i;
1968         for (i=0; i<nzA; i++)     v_p[imark+i] = vworkA[i];
1969         for (i=imark; i<nzB; i++) v_p[nzA+i]   = vworkB[i];
1970       }
1971       if (idx) {
1972         *idx = idx_p = mat->rowindices;
1973         if (imark > -1) {
1974           for (i=0; i<imark; i++) {
1975             idx_p[i] = cmap[cworkB[i]];
1976           }
1977         } else {
1978           for (i=0; i<nzB; i++) {
1979             if (cmap[cworkB[i]] < cstart) idx_p[i] = cmap[cworkB[i]];
1980             else break;
1981           }
1982           imark = i;
1983         }
1984         for (i=0; i<nzA; i++)     idx_p[imark+i] = cstart + cworkA[i];
1985         for (i=imark; i<nzB; i++) idx_p[nzA+i]   = cmap[cworkB[i]];
1986       }
1987     } else {
1988       if (idx) *idx = 0;
1989       if (v)   *v   = 0;
1990     }
1991   }
1992   *nz  = nztot;
1993   ierr = (*mat->A->ops->restorerow)(mat->A,lrow,&nzA,pcA,pvA);CHKERRQ(ierr);
1994   ierr = (*mat->B->ops->restorerow)(mat->B,lrow,&nzB,pcB,pvB);CHKERRQ(ierr);
1995   PetscFunctionReturn(0);
1996 }
1997 
1998 #undef __FUNCT__
1999 #define __FUNCT__ "MatRestoreRow_MPIAIJ"
2000 PetscErrorCode MatRestoreRow_MPIAIJ(Mat mat,PetscInt row,PetscInt *nz,PetscInt **idx,PetscScalar **v)
2001 {
2002   Mat_MPIAIJ *aij = (Mat_MPIAIJ*)mat->data;
2003 
2004   PetscFunctionBegin;
2005   if (!aij->getrowactive) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"MatGetRow() must be called first");
2006   aij->getrowactive = PETSC_FALSE;
2007   PetscFunctionReturn(0);
2008 }
2009 
2010 #undef __FUNCT__
2011 #define __FUNCT__ "MatNorm_MPIAIJ"
2012 PetscErrorCode MatNorm_MPIAIJ(Mat mat,NormType type,PetscReal *norm)
2013 {
2014   Mat_MPIAIJ     *aij  = (Mat_MPIAIJ*)mat->data;
2015   Mat_SeqAIJ     *amat = (Mat_SeqAIJ*)aij->A->data,*bmat = (Mat_SeqAIJ*)aij->B->data;
2016   PetscErrorCode ierr;
2017   PetscInt       i,j,cstart = mat->cmap->rstart;
2018   PetscReal      sum = 0.0;
2019   MatScalar      *v;
2020 
2021   PetscFunctionBegin;
2022   if (aij->size == 1) {
2023     ierr =  MatNorm(aij->A,type,norm);CHKERRQ(ierr);
2024   } else {
2025     if (type == NORM_FROBENIUS) {
2026       v = amat->a;
2027       for (i=0; i<amat->nz; i++) {
2028         sum += PetscRealPart(PetscConj(*v)*(*v)); v++;
2029       }
2030       v = bmat->a;
2031       for (i=0; i<bmat->nz; i++) {
2032         sum += PetscRealPart(PetscConj(*v)*(*v)); v++;
2033       }
2034       ierr  = MPI_Allreduce(&sum,norm,1,MPIU_REAL,MPIU_SUM,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
2035       *norm = PetscSqrtReal(*norm);
2036     } else if (type == NORM_1) { /* max column norm */
2037       PetscReal *tmp,*tmp2;
2038       PetscInt  *jj,*garray = aij->garray;
2039       ierr  = PetscMalloc((mat->cmap->N+1)*sizeof(PetscReal),&tmp);CHKERRQ(ierr);
2040       ierr  = PetscMalloc((mat->cmap->N+1)*sizeof(PetscReal),&tmp2);CHKERRQ(ierr);
2041       ierr  = PetscMemzero(tmp,mat->cmap->N*sizeof(PetscReal));CHKERRQ(ierr);
2042       *norm = 0.0;
2043       v     = amat->a; jj = amat->j;
2044       for (j=0; j<amat->nz; j++) {
2045         tmp[cstart + *jj++] += PetscAbsScalar(*v);  v++;
2046       }
2047       v = bmat->a; jj = bmat->j;
2048       for (j=0; j<bmat->nz; j++) {
2049         tmp[garray[*jj++]] += PetscAbsScalar(*v); v++;
2050       }
2051       ierr = MPI_Allreduce(tmp,tmp2,mat->cmap->N,MPIU_REAL,MPIU_SUM,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
2052       for (j=0; j<mat->cmap->N; j++) {
2053         if (tmp2[j] > *norm) *norm = tmp2[j];
2054       }
2055       ierr = PetscFree(tmp);CHKERRQ(ierr);
2056       ierr = PetscFree(tmp2);CHKERRQ(ierr);
2057     } else if (type == NORM_INFINITY) { /* max row norm */
2058       PetscReal ntemp = 0.0;
2059       for (j=0; j<aij->A->rmap->n; j++) {
2060         v   = amat->a + amat->i[j];
2061         sum = 0.0;
2062         for (i=0; i<amat->i[j+1]-amat->i[j]; i++) {
2063           sum += PetscAbsScalar(*v); v++;
2064         }
2065         v = bmat->a + bmat->i[j];
2066         for (i=0; i<bmat->i[j+1]-bmat->i[j]; i++) {
2067           sum += PetscAbsScalar(*v); v++;
2068         }
2069         if (sum > ntemp) ntemp = sum;
2070       }
2071       ierr = MPI_Allreduce(&ntemp,norm,1,MPIU_REAL,MPIU_MAX,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
2072     } else SETERRQ(PetscObjectComm((PetscObject)mat),PETSC_ERR_SUP,"No support for two norm");
2073   }
2074   PetscFunctionReturn(0);
2075 }
2076 
2077 #undef __FUNCT__
2078 #define __FUNCT__ "MatTranspose_MPIAIJ"
2079 PetscErrorCode MatTranspose_MPIAIJ(Mat A,MatReuse reuse,Mat *matout)
2080 {
2081   Mat_MPIAIJ     *a   = (Mat_MPIAIJ*)A->data;
2082   Mat_SeqAIJ     *Aloc=(Mat_SeqAIJ*)a->A->data,*Bloc=(Mat_SeqAIJ*)a->B->data;
2083   PetscErrorCode ierr;
2084   PetscInt       M      = A->rmap->N,N = A->cmap->N,ma,na,mb,nb,*ai,*aj,*bi,*bj,row,*cols,*cols_tmp,i;
2085   PetscInt       cstart = A->cmap->rstart,ncol;
2086   Mat            B;
2087   MatScalar      *array;
2088 
2089   PetscFunctionBegin;
2090   if (reuse == MAT_REUSE_MATRIX && A == *matout && M != N) SETERRQ(PetscObjectComm((PetscObject)A),PETSC_ERR_ARG_SIZ,"Square matrix only for in-place");
2091 
2092   ma = A->rmap->n; na = A->cmap->n; mb = a->B->rmap->n; nb = a->B->cmap->n;
2093   ai = Aloc->i; aj = Aloc->j;
2094   bi = Bloc->i; bj = Bloc->j;
2095   if (reuse == MAT_INITIAL_MATRIX || *matout == A) {
2096     PetscInt             *d_nnz,*g_nnz,*o_nnz;
2097     PetscSFNode          *oloc;
2098     PETSC_UNUSED PetscSF sf;
2099 
2100     ierr = PetscMalloc4(na,PetscInt,&d_nnz,na,PetscInt,&o_nnz,nb,PetscInt,&g_nnz,nb,PetscSFNode,&oloc);CHKERRQ(ierr);
2101     /* compute d_nnz for preallocation */
2102     ierr = PetscMemzero(d_nnz,na*sizeof(PetscInt));CHKERRQ(ierr);
2103     for (i=0; i<ai[ma]; i++) {
2104       d_nnz[aj[i]]++;
2105       aj[i] += cstart; /* global col index to be used by MatSetValues() */
2106     }
2107     /* compute local off-diagonal contributions */
2108     ierr = PetscMemzero(g_nnz,nb*sizeof(PetscInt));CHKERRQ(ierr);
2109     for (i=0; i<bi[ma]; i++) g_nnz[bj[i]]++;
2110     /* map those to global */
2111     ierr = PetscSFCreate(PetscObjectComm((PetscObject)A),&sf);CHKERRQ(ierr);
2112     ierr = PetscSFSetGraphLayout(sf,A->cmap,nb,NULL,PETSC_USE_POINTER,a->garray);CHKERRQ(ierr);
2113     ierr = PetscSFSetFromOptions(sf);CHKERRQ(ierr);
2114     ierr = PetscMemzero(o_nnz,na*sizeof(PetscInt));CHKERRQ(ierr);
2115     ierr = PetscSFReduceBegin(sf,MPIU_INT,g_nnz,o_nnz,MPIU_SUM);CHKERRQ(ierr);
2116     ierr = PetscSFReduceEnd(sf,MPIU_INT,g_nnz,o_nnz,MPIU_SUM);CHKERRQ(ierr);
2117     ierr = PetscSFDestroy(&sf);CHKERRQ(ierr);
2118 
2119     ierr = MatCreate(PetscObjectComm((PetscObject)A),&B);CHKERRQ(ierr);
2120     ierr = MatSetSizes(B,A->cmap->n,A->rmap->n,N,M);CHKERRQ(ierr);
2121     ierr = MatSetBlockSizes(B,A->cmap->bs,A->rmap->bs);CHKERRQ(ierr);
2122     ierr = MatSetType(B,((PetscObject)A)->type_name);CHKERRQ(ierr);
2123     ierr = MatMPIAIJSetPreallocation(B,0,d_nnz,0,o_nnz);CHKERRQ(ierr);
2124     ierr = PetscFree4(d_nnz,o_nnz,g_nnz,oloc);CHKERRQ(ierr);
2125   } else {
2126     B    = *matout;
2127     ierr = MatSetOption(B,MAT_NEW_NONZERO_ALLOCATION_ERR,PETSC_TRUE);CHKERRQ(ierr);
2128     for (i=0; i<ai[ma]; i++) aj[i] += cstart; /* global col index to be used by MatSetValues() */
2129   }
2130 
2131   /* copy over the A part */
2132   array = Aloc->a;
2133   row   = A->rmap->rstart;
2134   for (i=0; i<ma; i++) {
2135     ncol = ai[i+1]-ai[i];
2136     ierr = MatSetValues(B,ncol,aj,1,&row,array,INSERT_VALUES);CHKERRQ(ierr);
2137     row++;
2138     array += ncol; aj += ncol;
2139   }
2140   aj = Aloc->j;
2141   for (i=0; i<ai[ma]; i++) aj[i] -= cstart; /* resume local col index */
2142 
2143   /* copy over the B part */
2144   ierr  = PetscMalloc(bi[mb]*sizeof(PetscInt),&cols);CHKERRQ(ierr);
2145   ierr  = PetscMemzero(cols,bi[mb]*sizeof(PetscInt));CHKERRQ(ierr);
2146   array = Bloc->a;
2147   row   = A->rmap->rstart;
2148   for (i=0; i<bi[mb]; i++) cols[i] = a->garray[bj[i]];
2149   cols_tmp = cols;
2150   for (i=0; i<mb; i++) {
2151     ncol = bi[i+1]-bi[i];
2152     ierr = MatSetValues(B,ncol,cols_tmp,1,&row,array,INSERT_VALUES);CHKERRQ(ierr);
2153     row++;
2154     array += ncol; cols_tmp += ncol;
2155   }
2156   ierr = PetscFree(cols);CHKERRQ(ierr);
2157 
2158   ierr = MatAssemblyBegin(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
2159   ierr = MatAssemblyEnd(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
2160   if (reuse == MAT_INITIAL_MATRIX || *matout != A) {
2161     *matout = B;
2162   } else {
2163     ierr = MatHeaderMerge(A,B);CHKERRQ(ierr);
2164   }
2165   PetscFunctionReturn(0);
2166 }
2167 
2168 #undef __FUNCT__
2169 #define __FUNCT__ "MatDiagonalScale_MPIAIJ"
2170 PetscErrorCode MatDiagonalScale_MPIAIJ(Mat mat,Vec ll,Vec rr)
2171 {
2172   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
2173   Mat            a    = aij->A,b = aij->B;
2174   PetscErrorCode ierr;
2175   PetscInt       s1,s2,s3;
2176 
2177   PetscFunctionBegin;
2178   ierr = MatGetLocalSize(mat,&s2,&s3);CHKERRQ(ierr);
2179   if (rr) {
2180     ierr = VecGetLocalSize(rr,&s1);CHKERRQ(ierr);
2181     if (s1!=s3) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_SIZ,"right vector non-conforming local size");
2182     /* Overlap communication with computation. */
2183     ierr = VecScatterBegin(aij->Mvctx,rr,aij->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
2184   }
2185   if (ll) {
2186     ierr = VecGetLocalSize(ll,&s1);CHKERRQ(ierr);
2187     if (s1!=s2) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_SIZ,"left vector non-conforming local size");
2188     ierr = (*b->ops->diagonalscale)(b,ll,0);CHKERRQ(ierr);
2189   }
2190   /* scale  the diagonal block */
2191   ierr = (*a->ops->diagonalscale)(a,ll,rr);CHKERRQ(ierr);
2192 
2193   if (rr) {
2194     /* Do a scatter end and then right scale the off-diagonal block */
2195     ierr = VecScatterEnd(aij->Mvctx,rr,aij->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
2196     ierr = (*b->ops->diagonalscale)(b,0,aij->lvec);CHKERRQ(ierr);
2197   }
2198   PetscFunctionReturn(0);
2199 }
2200 
2201 #undef __FUNCT__
2202 #define __FUNCT__ "MatSetUnfactored_MPIAIJ"
2203 PetscErrorCode MatSetUnfactored_MPIAIJ(Mat A)
2204 {
2205   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
2206   PetscErrorCode ierr;
2207 
2208   PetscFunctionBegin;
2209   ierr = MatSetUnfactored(a->A);CHKERRQ(ierr);
2210   PetscFunctionReturn(0);
2211 }
2212 
2213 #undef __FUNCT__
2214 #define __FUNCT__ "MatEqual_MPIAIJ"
2215 PetscErrorCode MatEqual_MPIAIJ(Mat A,Mat B,PetscBool  *flag)
2216 {
2217   Mat_MPIAIJ     *matB = (Mat_MPIAIJ*)B->data,*matA = (Mat_MPIAIJ*)A->data;
2218   Mat            a,b,c,d;
2219   PetscBool      flg;
2220   PetscErrorCode ierr;
2221 
2222   PetscFunctionBegin;
2223   a = matA->A; b = matA->B;
2224   c = matB->A; d = matB->B;
2225 
2226   ierr = MatEqual(a,c,&flg);CHKERRQ(ierr);
2227   if (flg) {
2228     ierr = MatEqual(b,d,&flg);CHKERRQ(ierr);
2229   }
2230   ierr = MPI_Allreduce(&flg,flag,1,MPIU_BOOL,MPI_LAND,PetscObjectComm((PetscObject)A));CHKERRQ(ierr);
2231   PetscFunctionReturn(0);
2232 }
2233 
2234 #undef __FUNCT__
2235 #define __FUNCT__ "MatCopy_MPIAIJ"
2236 PetscErrorCode MatCopy_MPIAIJ(Mat A,Mat B,MatStructure str)
2237 {
2238   PetscErrorCode ierr;
2239   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
2240   Mat_MPIAIJ     *b = (Mat_MPIAIJ*)B->data;
2241 
2242   PetscFunctionBegin;
2243   /* If the two matrices don't have the same copy implementation, they aren't compatible for fast copy. */
2244   if ((str != SAME_NONZERO_PATTERN) || (A->ops->copy != B->ops->copy)) {
2245     /* because of the column compression in the off-processor part of the matrix a->B,
2246        the number of columns in a->B and b->B may be different, hence we cannot call
2247        the MatCopy() directly on the two parts. If need be, we can provide a more
2248        efficient copy than the MatCopy_Basic() by first uncompressing the a->B matrices
2249        then copying the submatrices */
2250     ierr = MatCopy_Basic(A,B,str);CHKERRQ(ierr);
2251   } else {
2252     ierr = MatCopy(a->A,b->A,str);CHKERRQ(ierr);
2253     ierr = MatCopy(a->B,b->B,str);CHKERRQ(ierr);
2254   }
2255   PetscFunctionReturn(0);
2256 }
2257 
2258 #undef __FUNCT__
2259 #define __FUNCT__ "MatSetUp_MPIAIJ"
2260 PetscErrorCode MatSetUp_MPIAIJ(Mat A)
2261 {
2262   PetscErrorCode ierr;
2263 
2264   PetscFunctionBegin;
2265   ierr =  MatMPIAIJSetPreallocation(A,PETSC_DEFAULT,0,PETSC_DEFAULT,0);CHKERRQ(ierr);
2266   PetscFunctionReturn(0);
2267 }
2268 
2269 #undef __FUNCT__
2270 #define __FUNCT__ "MatAXPYGetPreallocation_MPIAIJ"
2271 /* This is the same as MatAXPYGetPreallocation_SeqAIJ, except that the local-to-global map is provided */
2272 static PetscErrorCode MatAXPYGetPreallocation_MPIAIJ(Mat Y,const PetscInt *yltog,Mat X,const PetscInt *xltog,PetscInt *nnz)
2273 {
2274   PetscInt       i,m=Y->rmap->N;
2275   Mat_SeqAIJ     *x  = (Mat_SeqAIJ*)X->data;
2276   Mat_SeqAIJ     *y  = (Mat_SeqAIJ*)Y->data;
2277   const PetscInt *xi = x->i,*yi = y->i;
2278 
2279   PetscFunctionBegin;
2280   /* Set the number of nonzeros in the new matrix */
2281   for (i=0; i<m; i++) {
2282     PetscInt       j,k,nzx = xi[i+1] - xi[i],nzy = yi[i+1] - yi[i];
2283     const PetscInt *xj = x->j+xi[i],*yj = y->j+yi[i];
2284     nnz[i] = 0;
2285     for (j=0,k=0; j<nzx; j++) {                   /* Point in X */
2286       for (; k<nzy && yltog[yj[k]]<xltog[xj[j]]; k++) nnz[i]++; /* Catch up to X */
2287       if (k<nzy && yltog[yj[k]]==xltog[xj[j]]) k++;             /* Skip duplicate */
2288       nnz[i]++;
2289     }
2290     for (; k<nzy; k++) nnz[i]++;
2291   }
2292   PetscFunctionReturn(0);
2293 }
2294 
2295 #undef __FUNCT__
2296 #define __FUNCT__ "MatAXPY_MPIAIJ"
2297 PetscErrorCode MatAXPY_MPIAIJ(Mat Y,PetscScalar a,Mat X,MatStructure str)
2298 {
2299   PetscErrorCode ierr;
2300   PetscInt       i;
2301   Mat_MPIAIJ     *xx = (Mat_MPIAIJ*)X->data,*yy = (Mat_MPIAIJ*)Y->data;
2302   PetscBLASInt   bnz,one=1;
2303   Mat_SeqAIJ     *x,*y;
2304 
2305   PetscFunctionBegin;
2306   if (str == SAME_NONZERO_PATTERN) {
2307     PetscScalar alpha = a;
2308     x    = (Mat_SeqAIJ*)xx->A->data;
2309     ierr = PetscBLASIntCast(x->nz,&bnz);CHKERRQ(ierr);
2310     y    = (Mat_SeqAIJ*)yy->A->data;
2311     PetscStackCall("BLASaxpy",BLASaxpy_(&bnz,&alpha,x->a,&one,y->a,&one));
2312     x    = (Mat_SeqAIJ*)xx->B->data;
2313     y    = (Mat_SeqAIJ*)yy->B->data;
2314     ierr = PetscBLASIntCast(x->nz,&bnz);CHKERRQ(ierr);
2315     PetscStackCall("BLASaxpy",BLASaxpy_(&bnz,&alpha,x->a,&one,y->a,&one));
2316   } else if (str == SUBSET_NONZERO_PATTERN) {
2317     ierr = MatAXPY_SeqAIJ(yy->A,a,xx->A,str);CHKERRQ(ierr);
2318 
2319     x = (Mat_SeqAIJ*)xx->B->data;
2320     y = (Mat_SeqAIJ*)yy->B->data;
2321     if (y->xtoy && y->XtoY != xx->B) {
2322       ierr = PetscFree(y->xtoy);CHKERRQ(ierr);
2323       ierr = MatDestroy(&y->XtoY);CHKERRQ(ierr);
2324     }
2325     if (!y->xtoy) { /* get xtoy */
2326       ierr    = MatAXPYGetxtoy_Private(xx->B->rmap->n,x->i,x->j,xx->garray,y->i,y->j,yy->garray,&y->xtoy);CHKERRQ(ierr);
2327       y->XtoY = xx->B;
2328       ierr    = PetscObjectReference((PetscObject)xx->B);CHKERRQ(ierr);
2329     }
2330     for (i=0; i<x->nz; i++) y->a[y->xtoy[i]] += a*(x->a[i]);
2331   } else {
2332     Mat      B;
2333     PetscInt *nnz_d,*nnz_o;
2334     ierr = PetscMalloc(yy->A->rmap->N*sizeof(PetscInt),&nnz_d);CHKERRQ(ierr);
2335     ierr = PetscMalloc(yy->B->rmap->N*sizeof(PetscInt),&nnz_o);CHKERRQ(ierr);
2336     ierr = MatCreate(PetscObjectComm((PetscObject)Y),&B);CHKERRQ(ierr);
2337     ierr = PetscObjectSetName((PetscObject)B,((PetscObject)Y)->name);CHKERRQ(ierr);
2338     ierr = MatSetSizes(B,Y->rmap->n,Y->cmap->n,Y->rmap->N,Y->cmap->N);CHKERRQ(ierr);
2339     ierr = MatSetBlockSizes(B,Y->rmap->bs,Y->cmap->bs);CHKERRQ(ierr);
2340     ierr = MatSetType(B,MATMPIAIJ);CHKERRQ(ierr);
2341     ierr = MatAXPYGetPreallocation_SeqAIJ(yy->A,xx->A,nnz_d);CHKERRQ(ierr);
2342     ierr = MatAXPYGetPreallocation_MPIAIJ(yy->B,yy->garray,xx->B,xx->garray,nnz_o);CHKERRQ(ierr);
2343     ierr = MatMPIAIJSetPreallocation(B,0,nnz_d,0,nnz_o);CHKERRQ(ierr);
2344     ierr = MatAXPY_BasicWithPreallocation(B,Y,a,X,str);CHKERRQ(ierr);
2345     ierr = MatHeaderReplace(Y,B);CHKERRQ(ierr);
2346     ierr = PetscFree(nnz_d);CHKERRQ(ierr);
2347     ierr = PetscFree(nnz_o);CHKERRQ(ierr);
2348   }
2349   PetscFunctionReturn(0);
2350 }
2351 
2352 extern PetscErrorCode  MatConjugate_SeqAIJ(Mat);
2353 
2354 #undef __FUNCT__
2355 #define __FUNCT__ "MatConjugate_MPIAIJ"
2356 PetscErrorCode  MatConjugate_MPIAIJ(Mat mat)
2357 {
2358 #if defined(PETSC_USE_COMPLEX)
2359   PetscErrorCode ierr;
2360   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
2361 
2362   PetscFunctionBegin;
2363   ierr = MatConjugate_SeqAIJ(aij->A);CHKERRQ(ierr);
2364   ierr = MatConjugate_SeqAIJ(aij->B);CHKERRQ(ierr);
2365 #else
2366   PetscFunctionBegin;
2367 #endif
2368   PetscFunctionReturn(0);
2369 }
2370 
2371 #undef __FUNCT__
2372 #define __FUNCT__ "MatRealPart_MPIAIJ"
2373 PetscErrorCode MatRealPart_MPIAIJ(Mat A)
2374 {
2375   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
2376   PetscErrorCode ierr;
2377 
2378   PetscFunctionBegin;
2379   ierr = MatRealPart(a->A);CHKERRQ(ierr);
2380   ierr = MatRealPart(a->B);CHKERRQ(ierr);
2381   PetscFunctionReturn(0);
2382 }
2383 
2384 #undef __FUNCT__
2385 #define __FUNCT__ "MatImaginaryPart_MPIAIJ"
2386 PetscErrorCode MatImaginaryPart_MPIAIJ(Mat A)
2387 {
2388   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
2389   PetscErrorCode ierr;
2390 
2391   PetscFunctionBegin;
2392   ierr = MatImaginaryPart(a->A);CHKERRQ(ierr);
2393   ierr = MatImaginaryPart(a->B);CHKERRQ(ierr);
2394   PetscFunctionReturn(0);
2395 }
2396 
2397 #if defined(PETSC_HAVE_PBGL)
2398 
2399 #include <boost/parallel/mpi/bsp_process_group.hpp>
2400 #include <boost/graph/distributed/ilu_default_graph.hpp>
2401 #include <boost/graph/distributed/ilu_0_block.hpp>
2402 #include <boost/graph/distributed/ilu_preconditioner.hpp>
2403 #include <boost/graph/distributed/petsc/interface.hpp>
2404 #include <boost/multi_array.hpp>
2405 #include <boost/parallel/distributed_property_map->hpp>
2406 
2407 #undef __FUNCT__
2408 #define __FUNCT__ "MatILUFactorSymbolic_MPIAIJ"
2409 /*
2410   This uses the parallel ILU factorization of Peter Gottschling <pgottsch@osl.iu.edu>
2411 */
2412 PetscErrorCode MatILUFactorSymbolic_MPIAIJ(Mat fact,Mat A, IS isrow, IS iscol, const MatFactorInfo *info)
2413 {
2414   namespace petsc = boost::distributed::petsc;
2415 
2416   namespace graph_dist = boost::graph::distributed;
2417   using boost::graph::distributed::ilu_default::process_group_type;
2418   using boost::graph::ilu_permuted;
2419 
2420   PetscBool      row_identity, col_identity;
2421   PetscContainer c;
2422   PetscInt       m, n, M, N;
2423   PetscErrorCode ierr;
2424 
2425   PetscFunctionBegin;
2426   if (info->levels != 0) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_SUP,"Only levels = 0 supported for parallel ilu");
2427   ierr = ISIdentity(isrow, &row_identity);CHKERRQ(ierr);
2428   ierr = ISIdentity(iscol, &col_identity);CHKERRQ(ierr);
2429   if (!row_identity || !col_identity) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONG,"Row and column permutations must be identity for parallel ILU");
2430 
2431   process_group_type pg;
2432   typedef graph_dist::ilu_default::ilu_level_graph_type lgraph_type;
2433   lgraph_type  *lgraph_p   = new lgraph_type(petsc::num_global_vertices(A), pg, petsc::matrix_distribution(A, pg));
2434   lgraph_type& level_graph = *lgraph_p;
2435   graph_dist::ilu_default::graph_type&            graph(level_graph.graph);
2436 
2437   petsc::read_matrix(A, graph, get(boost::edge_weight, graph));
2438   ilu_permuted(level_graph);
2439 
2440   /* put together the new matrix */
2441   ierr = MatCreate(PetscObjectComm((PetscObject)A), fact);CHKERRQ(ierr);
2442   ierr = MatGetLocalSize(A, &m, &n);CHKERRQ(ierr);
2443   ierr = MatGetSize(A, &M, &N);CHKERRQ(ierr);
2444   ierr = MatSetSizes(fact, m, n, M, N);CHKERRQ(ierr);
2445   ierr = MatSetBlockSizes(fact,A->rmap->bs,A->cmap->bs);CHKERRQ(ierr);
2446   ierr = MatSetType(fact, ((PetscObject)A)->type_name);CHKERRQ(ierr);
2447   ierr = MatAssemblyBegin(fact, MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
2448   ierr = MatAssemblyEnd(fact, MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
2449 
2450   ierr = PetscContainerCreate(PetscObjectComm((PetscObject)A), &c);
2451   ierr = PetscContainerSetPointer(c, lgraph_p);
2452   ierr = PetscObjectCompose((PetscObject) (fact), "graph", (PetscObject) c);
2453   ierr = PetscContainerDestroy(&c);
2454   PetscFunctionReturn(0);
2455 }
2456 
2457 #undef __FUNCT__
2458 #define __FUNCT__ "MatLUFactorNumeric_MPIAIJ"
2459 PetscErrorCode MatLUFactorNumeric_MPIAIJ(Mat B,Mat A, const MatFactorInfo *info)
2460 {
2461   PetscFunctionBegin;
2462   PetscFunctionReturn(0);
2463 }
2464 
2465 #undef __FUNCT__
2466 #define __FUNCT__ "MatSolve_MPIAIJ"
2467 /*
2468   This uses the parallel ILU factorization of Peter Gottschling <pgottsch@osl.iu.edu>
2469 */
2470 PetscErrorCode MatSolve_MPIAIJ(Mat A, Vec b, Vec x)
2471 {
2472   namespace graph_dist = boost::graph::distributed;
2473 
2474   typedef graph_dist::ilu_default::ilu_level_graph_type lgraph_type;
2475   lgraph_type    *lgraph_p;
2476   PetscContainer c;
2477   PetscErrorCode ierr;
2478 
2479   PetscFunctionBegin;
2480   ierr = PetscObjectQuery((PetscObject) A, "graph", (PetscObject*) &c);CHKERRQ(ierr);
2481   ierr = PetscContainerGetPointer(c, (void**) &lgraph_p);CHKERRQ(ierr);
2482   ierr = VecCopy(b, x);CHKERRQ(ierr);
2483 
2484   PetscScalar *array_x;
2485   ierr = VecGetArray(x, &array_x);CHKERRQ(ierr);
2486   PetscInt sx;
2487   ierr = VecGetSize(x, &sx);CHKERRQ(ierr);
2488 
2489   PetscScalar *array_b;
2490   ierr = VecGetArray(b, &array_b);CHKERRQ(ierr);
2491   PetscInt sb;
2492   ierr = VecGetSize(b, &sb);CHKERRQ(ierr);
2493 
2494   lgraph_type& level_graph = *lgraph_p;
2495   graph_dist::ilu_default::graph_type&            graph(level_graph.graph);
2496 
2497   typedef boost::multi_array_ref<PetscScalar, 1> array_ref_type;
2498   array_ref_type                                 ref_b(array_b, boost::extents[num_vertices(graph)]);
2499   array_ref_type                                 ref_x(array_x, boost::extents[num_vertices(graph)]);
2500 
2501   typedef boost::iterator_property_map<array_ref_type::iterator,
2502                                        boost::property_map<graph_dist::ilu_default::graph_type, boost::vertex_index_t>::type>  gvector_type;
2503   gvector_type                                   vector_b(ref_b.begin(), get(boost::vertex_index, graph));
2504   gvector_type                                   vector_x(ref_x.begin(), get(boost::vertex_index, graph));
2505 
2506   ilu_set_solve(*lgraph_p, vector_b, vector_x);
2507   PetscFunctionReturn(0);
2508 }
2509 #endif
2510 
2511 typedef struct { /* used by MatGetRedundantMatrix() for reusing matredundant */
2512   PetscInt    nzlocal,nsends,nrecvs;
2513   PetscMPIInt *send_rank,*recv_rank;
2514   PetscInt    *sbuf_nz,*rbuf_nz,*sbuf_j,**rbuf_j;
2515   PetscScalar *sbuf_a,**rbuf_a;
2516   PetscErrorCode (*Destroy)(Mat);
2517 } Mat_Redundant;
2518 
2519 #undef __FUNCT__
2520 #define __FUNCT__ "PetscContainerDestroy_MatRedundant"
2521 PetscErrorCode PetscContainerDestroy_MatRedundant(void *ptr)
2522 {
2523   PetscErrorCode ierr;
2524   Mat_Redundant  *redund=(Mat_Redundant*)ptr;
2525   PetscInt       i;
2526 
2527   PetscFunctionBegin;
2528   ierr = PetscFree2(redund->send_rank,redund->recv_rank);CHKERRQ(ierr);
2529   ierr = PetscFree(redund->sbuf_j);CHKERRQ(ierr);
2530   ierr = PetscFree(redund->sbuf_a);CHKERRQ(ierr);
2531   for (i=0; i<redund->nrecvs; i++) {
2532     ierr = PetscFree(redund->rbuf_j[i]);CHKERRQ(ierr);
2533     ierr = PetscFree(redund->rbuf_a[i]);CHKERRQ(ierr);
2534   }
2535   ierr = PetscFree4(redund->sbuf_nz,redund->rbuf_nz,redund->rbuf_j,redund->rbuf_a);CHKERRQ(ierr);
2536   ierr = PetscFree(redund);CHKERRQ(ierr);
2537   PetscFunctionReturn(0);
2538 }
2539 
2540 #undef __FUNCT__
2541 #define __FUNCT__ "MatDestroy_MatRedundant"
2542 PetscErrorCode MatDestroy_MatRedundant(Mat A)
2543 {
2544   PetscErrorCode ierr;
2545   PetscContainer container;
2546   Mat_Redundant  *redund=NULL;
2547 
2548   PetscFunctionBegin;
2549   ierr = PetscObjectQuery((PetscObject)A,"Mat_Redundant",(PetscObject*)&container);CHKERRQ(ierr);
2550   if (!container) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_PLIB,"Container does not exit");
2551   ierr = PetscContainerGetPointer(container,(void**)&redund);CHKERRQ(ierr);
2552 
2553   A->ops->destroy = redund->Destroy;
2554 
2555   ierr = PetscObjectCompose((PetscObject)A,"Mat_Redundant",0);CHKERRQ(ierr);
2556   if (A->ops->destroy) {
2557     ierr = (*A->ops->destroy)(A);CHKERRQ(ierr);
2558   }
2559   PetscFunctionReturn(0);
2560 }
2561 
2562 #undef __FUNCT__
2563 #define __FUNCT__ "MatGetRedundantMatrix_MPIAIJ"
2564 PetscErrorCode MatGetRedundantMatrix_MPIAIJ(Mat mat,PetscInt nsubcomm,MPI_Comm subcomm,PetscInt mlocal_sub,MatReuse reuse,Mat *matredundant)
2565 {
2566   PetscMPIInt    rank,size;
2567   MPI_Comm       comm;
2568   PetscErrorCode ierr;
2569   PetscInt       nsends    = 0,nrecvs=0,i,rownz_max=0;
2570   PetscMPIInt    *send_rank= NULL,*recv_rank=NULL;
2571   PetscInt       *rowrange = mat->rmap->range;
2572   Mat_MPIAIJ     *aij      = (Mat_MPIAIJ*)mat->data;
2573   Mat            A         = aij->A,B=aij->B,C=*matredundant;
2574   Mat_SeqAIJ     *a        = (Mat_SeqAIJ*)A->data,*b=(Mat_SeqAIJ*)B->data;
2575   PetscScalar    *sbuf_a;
2576   PetscInt       nzlocal=a->nz+b->nz;
2577   PetscInt       j,cstart=mat->cmap->rstart,cend=mat->cmap->rend,row,nzA,nzB,ncols,*cworkA,*cworkB;
2578   PetscInt       rstart=mat->rmap->rstart,rend=mat->rmap->rend,*bmap=aij->garray,M,N;
2579   PetscInt       *cols,ctmp,lwrite,*rptr,l,*sbuf_j;
2580   MatScalar      *aworkA,*aworkB;
2581   PetscScalar    *vals;
2582   PetscMPIInt    tag1,tag2,tag3,imdex;
2583   MPI_Request    *s_waits1=NULL,*s_waits2=NULL,*s_waits3=NULL;
2584   MPI_Request    *r_waits1=NULL,*r_waits2=NULL,*r_waits3=NULL;
2585   MPI_Status     recv_status,*send_status;
2586   PetscInt       *sbuf_nz=NULL,*rbuf_nz=NULL,count;
2587   PetscInt       **rbuf_j=NULL;
2588   PetscScalar    **rbuf_a=NULL;
2589   Mat_Redundant  *redund =NULL;
2590   PetscContainer container;
2591 
2592   PetscFunctionBegin;
2593   ierr = PetscObjectGetComm((PetscObject)mat,&comm);CHKERRQ(ierr);
2594   ierr = MPI_Comm_rank(comm,&rank);CHKERRQ(ierr);
2595   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
2596 
2597   if (reuse == MAT_REUSE_MATRIX) {
2598     ierr = MatGetSize(C,&M,&N);CHKERRQ(ierr);
2599     if (M != N || M != mat->rmap->N) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_SIZ,"Cannot reuse matrix. Wrong global size");
2600     ierr = MatGetLocalSize(C,&M,&N);CHKERRQ(ierr);
2601     if (M != N || M != mlocal_sub) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_SIZ,"Cannot reuse matrix. Wrong local size");
2602     ierr = PetscObjectQuery((PetscObject)C,"Mat_Redundant",(PetscObject*)&container);CHKERRQ(ierr);
2603     if (!container) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_PLIB,"Container does not exit");
2604     ierr = PetscContainerGetPointer(container,(void**)&redund);CHKERRQ(ierr);
2605     if (nzlocal != redund->nzlocal) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_SIZ,"Cannot reuse matrix. Wrong nzlocal");
2606 
2607     nsends    = redund->nsends;
2608     nrecvs    = redund->nrecvs;
2609     send_rank = redund->send_rank;
2610     recv_rank = redund->recv_rank;
2611     sbuf_nz   = redund->sbuf_nz;
2612     rbuf_nz   = redund->rbuf_nz;
2613     sbuf_j    = redund->sbuf_j;
2614     sbuf_a    = redund->sbuf_a;
2615     rbuf_j    = redund->rbuf_j;
2616     rbuf_a    = redund->rbuf_a;
2617   }
2618 
2619   if (reuse == MAT_INITIAL_MATRIX) {
2620     PetscMPIInt subrank,subsize;
2621     PetscInt    nleftover,np_subcomm;
2622     /* get the destination processors' id send_rank, nsends and nrecvs */
2623     ierr = MPI_Comm_rank(subcomm,&subrank);CHKERRQ(ierr);
2624     ierr = MPI_Comm_size(subcomm,&subsize);CHKERRQ(ierr);
2625     ierr = PetscMalloc2(size,PetscMPIInt,&send_rank,size,PetscMPIInt,&recv_rank);CHKERRQ(ierr);
2626 
2627     np_subcomm = size/nsubcomm;
2628     nleftover  = size - nsubcomm*np_subcomm;
2629 
2630     nsends = 0; nrecvs = 0;
2631     for (i=0; i<size; i++) { /* i=rank*/
2632       if (subrank == i/nsubcomm && rank != i) { /* my_subrank == other's subrank */
2633         send_rank[nsends]   = i; nsends++;
2634         recv_rank[nrecvs++] = i;
2635       }
2636     }
2637     if (rank >= size - nleftover) { /* this proc is a leftover processor */
2638       i = size-nleftover-1;
2639       j = 0;
2640       while (j < nsubcomm - nleftover) {
2641         send_rank[nsends++] = i;
2642         i--; j++;
2643       }
2644     }
2645 
2646     if (nleftover && subsize == size/nsubcomm && subrank==subsize-1) { /* this proc recvs from leftover processors */
2647       for (i=0; i<nleftover; i++) {
2648         recv_rank[nrecvs++] = size-nleftover+i;
2649       }
2650     }
2651 
2652     /* allocate sbuf_j, sbuf_a */
2653     i    = nzlocal + rowrange[rank+1] - rowrange[rank] + 2;
2654     ierr = PetscMalloc(i*sizeof(PetscInt),&sbuf_j);CHKERRQ(ierr);
2655     ierr = PetscMalloc((nzlocal+1)*sizeof(PetscScalar),&sbuf_a);CHKERRQ(ierr);
2656   } /* endof if (reuse == MAT_INITIAL_MATRIX) */
2657 
2658   /* copy mat's local entries into the buffers */
2659   if (reuse == MAT_INITIAL_MATRIX) {
2660     rownz_max = 0;
2661     rptr      = sbuf_j;
2662     cols      = sbuf_j + rend-rstart + 1;
2663     vals      = sbuf_a;
2664     rptr[0]   = 0;
2665     for (i=0; i<rend-rstart; i++) {
2666       row    = i + rstart;
2667       nzA    = a->i[i+1] - a->i[i]; nzB = b->i[i+1] - b->i[i];
2668       ncols  = nzA + nzB;
2669       cworkA = a->j + a->i[i]; cworkB = b->j + b->i[i];
2670       aworkA = a->a + a->i[i]; aworkB = b->a + b->i[i];
2671       /* load the column indices for this row into cols */
2672       lwrite = 0;
2673       for (l=0; l<nzB; l++) {
2674         if ((ctmp = bmap[cworkB[l]]) < cstart) {
2675           vals[lwrite]   = aworkB[l];
2676           cols[lwrite++] = ctmp;
2677         }
2678       }
2679       for (l=0; l<nzA; l++) {
2680         vals[lwrite]   = aworkA[l];
2681         cols[lwrite++] = cstart + cworkA[l];
2682       }
2683       for (l=0; l<nzB; l++) {
2684         if ((ctmp = bmap[cworkB[l]]) >= cend) {
2685           vals[lwrite]   = aworkB[l];
2686           cols[lwrite++] = ctmp;
2687         }
2688       }
2689       vals     += ncols;
2690       cols     += ncols;
2691       rptr[i+1] = rptr[i] + ncols;
2692       if (rownz_max < ncols) rownz_max = ncols;
2693     }
2694     if (rptr[rend-rstart] != a->nz + b->nz) SETERRQ4(PETSC_COMM_SELF,PETSC_ERR_PLIB, "rptr[%d] %d != %d + %d",rend-rstart,rptr[rend-rstart+1],a->nz,b->nz);
2695   } else { /* only copy matrix values into sbuf_a */
2696     rptr    = sbuf_j;
2697     vals    = sbuf_a;
2698     rptr[0] = 0;
2699     for (i=0; i<rend-rstart; i++) {
2700       row    = i + rstart;
2701       nzA    = a->i[i+1] - a->i[i]; nzB = b->i[i+1] - b->i[i];
2702       ncols  = nzA + nzB;
2703       cworkB = b->j + b->i[i];
2704       aworkA = a->a + a->i[i];
2705       aworkB = b->a + b->i[i];
2706       lwrite = 0;
2707       for (l=0; l<nzB; l++) {
2708         if ((ctmp = bmap[cworkB[l]]) < cstart) vals[lwrite++] = aworkB[l];
2709       }
2710       for (l=0; l<nzA; l++) vals[lwrite++] = aworkA[l];
2711       for (l=0; l<nzB; l++) {
2712         if ((ctmp = bmap[cworkB[l]]) >= cend) vals[lwrite++] = aworkB[l];
2713       }
2714       vals     += ncols;
2715       rptr[i+1] = rptr[i] + ncols;
2716     }
2717   } /* endof if (reuse == MAT_INITIAL_MATRIX) */
2718 
2719   /* send nzlocal to others, and recv other's nzlocal */
2720   /*--------------------------------------------------*/
2721   if (reuse == MAT_INITIAL_MATRIX) {
2722     ierr = PetscMalloc2(3*(nsends + nrecvs)+1,MPI_Request,&s_waits3,nsends+1,MPI_Status,&send_status);CHKERRQ(ierr);
2723 
2724     s_waits2 = s_waits3 + nsends;
2725     s_waits1 = s_waits2 + nsends;
2726     r_waits1 = s_waits1 + nsends;
2727     r_waits2 = r_waits1 + nrecvs;
2728     r_waits3 = r_waits2 + nrecvs;
2729   } else {
2730     ierr = PetscMalloc2(nsends + nrecvs +1,MPI_Request,&s_waits3,nsends+1,MPI_Status,&send_status);CHKERRQ(ierr);
2731 
2732     r_waits3 = s_waits3 + nsends;
2733   }
2734 
2735   ierr = PetscObjectGetNewTag((PetscObject)mat,&tag3);CHKERRQ(ierr);
2736   if (reuse == MAT_INITIAL_MATRIX) {
2737     /* get new tags to keep the communication clean */
2738     ierr = PetscObjectGetNewTag((PetscObject)mat,&tag1);CHKERRQ(ierr);
2739     ierr = PetscObjectGetNewTag((PetscObject)mat,&tag2);CHKERRQ(ierr);
2740     ierr = PetscMalloc4(nsends,PetscInt,&sbuf_nz,nrecvs,PetscInt,&rbuf_nz,nrecvs,PetscInt*,&rbuf_j,nrecvs,PetscScalar*,&rbuf_a);CHKERRQ(ierr);
2741 
2742     /* post receives of other's nzlocal */
2743     for (i=0; i<nrecvs; i++) {
2744       ierr = MPI_Irecv(rbuf_nz+i,1,MPIU_INT,MPI_ANY_SOURCE,tag1,comm,r_waits1+i);CHKERRQ(ierr);
2745     }
2746     /* send nzlocal to others */
2747     for (i=0; i<nsends; i++) {
2748       sbuf_nz[i] = nzlocal;
2749       ierr       = MPI_Isend(sbuf_nz+i,1,MPIU_INT,send_rank[i],tag1,comm,s_waits1+i);CHKERRQ(ierr);
2750     }
2751     /* wait on receives of nzlocal; allocate space for rbuf_j, rbuf_a */
2752     count = nrecvs;
2753     while (count) {
2754       ierr = MPI_Waitany(nrecvs,r_waits1,&imdex,&recv_status);CHKERRQ(ierr);
2755 
2756       recv_rank[imdex] = recv_status.MPI_SOURCE;
2757       /* allocate rbuf_a and rbuf_j; then post receives of rbuf_j */
2758       ierr = PetscMalloc((rbuf_nz[imdex]+1)*sizeof(PetscScalar),&rbuf_a[imdex]);CHKERRQ(ierr);
2759 
2760       i = rowrange[recv_status.MPI_SOURCE+1] - rowrange[recv_status.MPI_SOURCE]; /* number of expected mat->i */
2761 
2762       rbuf_nz[imdex] += i + 2;
2763 
2764       ierr = PetscMalloc(rbuf_nz[imdex]*sizeof(PetscInt),&rbuf_j[imdex]);CHKERRQ(ierr);
2765       ierr = MPI_Irecv(rbuf_j[imdex],rbuf_nz[imdex],MPIU_INT,recv_status.MPI_SOURCE,tag2,comm,r_waits2+imdex);CHKERRQ(ierr);
2766       count--;
2767     }
2768     /* wait on sends of nzlocal */
2769     if (nsends) {ierr = MPI_Waitall(nsends,s_waits1,send_status);CHKERRQ(ierr);}
2770     /* send mat->i,j to others, and recv from other's */
2771     /*------------------------------------------------*/
2772     for (i=0; i<nsends; i++) {
2773       j    = nzlocal + rowrange[rank+1] - rowrange[rank] + 1;
2774       ierr = MPI_Isend(sbuf_j,j,MPIU_INT,send_rank[i],tag2,comm,s_waits2+i);CHKERRQ(ierr);
2775     }
2776     /* wait on receives of mat->i,j */
2777     /*------------------------------*/
2778     count = nrecvs;
2779     while (count) {
2780       ierr = MPI_Waitany(nrecvs,r_waits2,&imdex,&recv_status);CHKERRQ(ierr);
2781       if (recv_rank[imdex] != recv_status.MPI_SOURCE) SETERRQ2(PETSC_COMM_SELF,1, "recv_rank %d != MPI_SOURCE %d",recv_rank[imdex],recv_status.MPI_SOURCE);
2782       count--;
2783     }
2784     /* wait on sends of mat->i,j */
2785     /*---------------------------*/
2786     if (nsends) {
2787       ierr = MPI_Waitall(nsends,s_waits2,send_status);CHKERRQ(ierr);
2788     }
2789   } /* endof if (reuse == MAT_INITIAL_MATRIX) */
2790 
2791   /* post receives, send and receive mat->a */
2792   /*----------------------------------------*/
2793   for (imdex=0; imdex<nrecvs; imdex++) {
2794     ierr = MPI_Irecv(rbuf_a[imdex],rbuf_nz[imdex],MPIU_SCALAR,recv_rank[imdex],tag3,comm,r_waits3+imdex);CHKERRQ(ierr);
2795   }
2796   for (i=0; i<nsends; i++) {
2797     ierr = MPI_Isend(sbuf_a,nzlocal,MPIU_SCALAR,send_rank[i],tag3,comm,s_waits3+i);CHKERRQ(ierr);
2798   }
2799   count = nrecvs;
2800   while (count) {
2801     ierr = MPI_Waitany(nrecvs,r_waits3,&imdex,&recv_status);CHKERRQ(ierr);
2802     if (recv_rank[imdex] != recv_status.MPI_SOURCE) SETERRQ2(PETSC_COMM_SELF,1, "recv_rank %d != MPI_SOURCE %d",recv_rank[imdex],recv_status.MPI_SOURCE);
2803     count--;
2804   }
2805   if (nsends) {
2806     ierr = MPI_Waitall(nsends,s_waits3,send_status);CHKERRQ(ierr);
2807   }
2808 
2809   ierr = PetscFree2(s_waits3,send_status);CHKERRQ(ierr);
2810 
2811   /* create redundant matrix */
2812   /*-------------------------*/
2813   if (reuse == MAT_INITIAL_MATRIX) {
2814     /* compute rownz_max for preallocation */
2815     for (imdex=0; imdex<nrecvs; imdex++) {
2816       j    = rowrange[recv_rank[imdex]+1] - rowrange[recv_rank[imdex]];
2817       rptr = rbuf_j[imdex];
2818       for (i=0; i<j; i++) {
2819         ncols = rptr[i+1] - rptr[i];
2820         if (rownz_max < ncols) rownz_max = ncols;
2821       }
2822     }
2823 
2824     ierr = MatCreate(subcomm,&C);CHKERRQ(ierr);
2825     ierr = MatSetSizes(C,mlocal_sub,mlocal_sub,PETSC_DECIDE,PETSC_DECIDE);CHKERRQ(ierr);
2826     ierr = MatSetBlockSizes(C,mat->rmap->bs,mat->cmap->bs);CHKERRQ(ierr);
2827     ierr = MatSetFromOptions(C);CHKERRQ(ierr);
2828     ierr = MatSeqAIJSetPreallocation(C,rownz_max,NULL);CHKERRQ(ierr);
2829     ierr = MatMPIAIJSetPreallocation(C,rownz_max,NULL,rownz_max,NULL);CHKERRQ(ierr);
2830   } else {
2831     C = *matredundant;
2832   }
2833 
2834   /* insert local matrix entries */
2835   rptr = sbuf_j;
2836   cols = sbuf_j + rend-rstart + 1;
2837   vals = sbuf_a;
2838   for (i=0; i<rend-rstart; i++) {
2839     row   = i + rstart;
2840     ncols = rptr[i+1] - rptr[i];
2841     ierr  = MatSetValues(C,1,&row,ncols,cols,vals,INSERT_VALUES);CHKERRQ(ierr);
2842     vals += ncols;
2843     cols += ncols;
2844   }
2845   /* insert received matrix entries */
2846   for (imdex=0; imdex<nrecvs; imdex++) {
2847     rstart = rowrange[recv_rank[imdex]];
2848     rend   = rowrange[recv_rank[imdex]+1];
2849     rptr   = rbuf_j[imdex];
2850     cols   = rbuf_j[imdex] + rend-rstart + 1;
2851     vals   = rbuf_a[imdex];
2852     for (i=0; i<rend-rstart; i++) {
2853       row   = i + rstart;
2854       ncols = rptr[i+1] - rptr[i];
2855       ierr  = MatSetValues(C,1,&row,ncols,cols,vals,INSERT_VALUES);CHKERRQ(ierr);
2856       vals += ncols;
2857       cols += ncols;
2858     }
2859   }
2860   ierr = MatAssemblyBegin(C,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
2861   ierr = MatAssemblyEnd(C,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
2862   ierr = MatGetSize(C,&M,&N);CHKERRQ(ierr);
2863   if (M != mat->rmap->N || N != mat->cmap->N) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_INCOMP,"redundant mat size %d != input mat size %d",M,mat->rmap->N);
2864   if (reuse == MAT_INITIAL_MATRIX) {
2865     PetscContainer container;
2866     *matredundant = C;
2867     /* create a supporting struct and attach it to C for reuse */
2868     ierr = PetscNewLog(C,Mat_Redundant,&redund);CHKERRQ(ierr);
2869     ierr = PetscContainerCreate(PETSC_COMM_SELF,&container);CHKERRQ(ierr);
2870     ierr = PetscContainerSetPointer(container,redund);CHKERRQ(ierr);
2871     ierr = PetscContainerSetUserDestroy(container,PetscContainerDestroy_MatRedundant);CHKERRQ(ierr);
2872     ierr = PetscObjectCompose((PetscObject)C,"Mat_Redundant",(PetscObject)container);CHKERRQ(ierr);
2873     ierr = PetscContainerDestroy(&container);CHKERRQ(ierr);
2874 
2875     redund->nzlocal   = nzlocal;
2876     redund->nsends    = nsends;
2877     redund->nrecvs    = nrecvs;
2878     redund->send_rank = send_rank;
2879     redund->recv_rank = recv_rank;
2880     redund->sbuf_nz   = sbuf_nz;
2881     redund->rbuf_nz   = rbuf_nz;
2882     redund->sbuf_j    = sbuf_j;
2883     redund->sbuf_a    = sbuf_a;
2884     redund->rbuf_j    = rbuf_j;
2885     redund->rbuf_a    = rbuf_a;
2886 
2887     redund->Destroy = C->ops->destroy;
2888     C->ops->destroy = MatDestroy_MatRedundant;
2889   }
2890   PetscFunctionReturn(0);
2891 }
2892 
2893 #undef __FUNCT__
2894 #define __FUNCT__ "MatGetRowMaxAbs_MPIAIJ"
2895 PetscErrorCode MatGetRowMaxAbs_MPIAIJ(Mat A, Vec v, PetscInt idx[])
2896 {
2897   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
2898   PetscErrorCode ierr;
2899   PetscInt       i,*idxb = 0;
2900   PetscScalar    *va,*vb;
2901   Vec            vtmp;
2902 
2903   PetscFunctionBegin;
2904   ierr = MatGetRowMaxAbs(a->A,v,idx);CHKERRQ(ierr);
2905   ierr = VecGetArray(v,&va);CHKERRQ(ierr);
2906   if (idx) {
2907     for (i=0; i<A->rmap->n; i++) {
2908       if (PetscAbsScalar(va[i])) idx[i] += A->cmap->rstart;
2909     }
2910   }
2911 
2912   ierr = VecCreateSeq(PETSC_COMM_SELF,A->rmap->n,&vtmp);CHKERRQ(ierr);
2913   if (idx) {
2914     ierr = PetscMalloc(A->rmap->n*sizeof(PetscInt),&idxb);CHKERRQ(ierr);
2915   }
2916   ierr = MatGetRowMaxAbs(a->B,vtmp,idxb);CHKERRQ(ierr);
2917   ierr = VecGetArray(vtmp,&vb);CHKERRQ(ierr);
2918 
2919   for (i=0; i<A->rmap->n; i++) {
2920     if (PetscAbsScalar(va[i]) < PetscAbsScalar(vb[i])) {
2921       va[i] = vb[i];
2922       if (idx) idx[i] = a->garray[idxb[i]];
2923     }
2924   }
2925 
2926   ierr = VecRestoreArray(v,&va);CHKERRQ(ierr);
2927   ierr = VecRestoreArray(vtmp,&vb);CHKERRQ(ierr);
2928   ierr = PetscFree(idxb);CHKERRQ(ierr);
2929   ierr = VecDestroy(&vtmp);CHKERRQ(ierr);
2930   PetscFunctionReturn(0);
2931 }
2932 
2933 #undef __FUNCT__
2934 #define __FUNCT__ "MatGetRowMinAbs_MPIAIJ"
2935 PetscErrorCode MatGetRowMinAbs_MPIAIJ(Mat A, Vec v, PetscInt idx[])
2936 {
2937   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
2938   PetscErrorCode ierr;
2939   PetscInt       i,*idxb = 0;
2940   PetscScalar    *va,*vb;
2941   Vec            vtmp;
2942 
2943   PetscFunctionBegin;
2944   ierr = MatGetRowMinAbs(a->A,v,idx);CHKERRQ(ierr);
2945   ierr = VecGetArray(v,&va);CHKERRQ(ierr);
2946   if (idx) {
2947     for (i=0; i<A->cmap->n; i++) {
2948       if (PetscAbsScalar(va[i])) idx[i] += A->cmap->rstart;
2949     }
2950   }
2951 
2952   ierr = VecCreateSeq(PETSC_COMM_SELF,A->rmap->n,&vtmp);CHKERRQ(ierr);
2953   if (idx) {
2954     ierr = PetscMalloc(A->rmap->n*sizeof(PetscInt),&idxb);CHKERRQ(ierr);
2955   }
2956   ierr = MatGetRowMinAbs(a->B,vtmp,idxb);CHKERRQ(ierr);
2957   ierr = VecGetArray(vtmp,&vb);CHKERRQ(ierr);
2958 
2959   for (i=0; i<A->rmap->n; i++) {
2960     if (PetscAbsScalar(va[i]) > PetscAbsScalar(vb[i])) {
2961       va[i] = vb[i];
2962       if (idx) idx[i] = a->garray[idxb[i]];
2963     }
2964   }
2965 
2966   ierr = VecRestoreArray(v,&va);CHKERRQ(ierr);
2967   ierr = VecRestoreArray(vtmp,&vb);CHKERRQ(ierr);
2968   ierr = PetscFree(idxb);CHKERRQ(ierr);
2969   ierr = VecDestroy(&vtmp);CHKERRQ(ierr);
2970   PetscFunctionReturn(0);
2971 }
2972 
2973 #undef __FUNCT__
2974 #define __FUNCT__ "MatGetRowMin_MPIAIJ"
2975 PetscErrorCode MatGetRowMin_MPIAIJ(Mat A, Vec v, PetscInt idx[])
2976 {
2977   Mat_MPIAIJ     *mat   = (Mat_MPIAIJ*) A->data;
2978   PetscInt       n      = A->rmap->n;
2979   PetscInt       cstart = A->cmap->rstart;
2980   PetscInt       *cmap  = mat->garray;
2981   PetscInt       *diagIdx, *offdiagIdx;
2982   Vec            diagV, offdiagV;
2983   PetscScalar    *a, *diagA, *offdiagA;
2984   PetscInt       r;
2985   PetscErrorCode ierr;
2986 
2987   PetscFunctionBegin;
2988   ierr = PetscMalloc2(n,PetscInt,&diagIdx,n,PetscInt,&offdiagIdx);CHKERRQ(ierr);
2989   ierr = VecCreateSeq(PetscObjectComm((PetscObject)A), n, &diagV);CHKERRQ(ierr);
2990   ierr = VecCreateSeq(PetscObjectComm((PetscObject)A), n, &offdiagV);CHKERRQ(ierr);
2991   ierr = MatGetRowMin(mat->A, diagV,    diagIdx);CHKERRQ(ierr);
2992   ierr = MatGetRowMin(mat->B, offdiagV, offdiagIdx);CHKERRQ(ierr);
2993   ierr = VecGetArray(v,        &a);CHKERRQ(ierr);
2994   ierr = VecGetArray(diagV,    &diagA);CHKERRQ(ierr);
2995   ierr = VecGetArray(offdiagV, &offdiagA);CHKERRQ(ierr);
2996   for (r = 0; r < n; ++r) {
2997     if (PetscAbsScalar(diagA[r]) <= PetscAbsScalar(offdiagA[r])) {
2998       a[r]   = diagA[r];
2999       idx[r] = cstart + diagIdx[r];
3000     } else {
3001       a[r]   = offdiagA[r];
3002       idx[r] = cmap[offdiagIdx[r]];
3003     }
3004   }
3005   ierr = VecRestoreArray(v,        &a);CHKERRQ(ierr);
3006   ierr = VecRestoreArray(diagV,    &diagA);CHKERRQ(ierr);
3007   ierr = VecRestoreArray(offdiagV, &offdiagA);CHKERRQ(ierr);
3008   ierr = VecDestroy(&diagV);CHKERRQ(ierr);
3009   ierr = VecDestroy(&offdiagV);CHKERRQ(ierr);
3010   ierr = PetscFree2(diagIdx, offdiagIdx);CHKERRQ(ierr);
3011   PetscFunctionReturn(0);
3012 }
3013 
3014 #undef __FUNCT__
3015 #define __FUNCT__ "MatGetRowMax_MPIAIJ"
3016 PetscErrorCode MatGetRowMax_MPIAIJ(Mat A, Vec v, PetscInt idx[])
3017 {
3018   Mat_MPIAIJ     *mat   = (Mat_MPIAIJ*) A->data;
3019   PetscInt       n      = A->rmap->n;
3020   PetscInt       cstart = A->cmap->rstart;
3021   PetscInt       *cmap  = mat->garray;
3022   PetscInt       *diagIdx, *offdiagIdx;
3023   Vec            diagV, offdiagV;
3024   PetscScalar    *a, *diagA, *offdiagA;
3025   PetscInt       r;
3026   PetscErrorCode ierr;
3027 
3028   PetscFunctionBegin;
3029   ierr = PetscMalloc2(n,PetscInt,&diagIdx,n,PetscInt,&offdiagIdx);CHKERRQ(ierr);
3030   ierr = VecCreateSeq(PETSC_COMM_SELF, n, &diagV);CHKERRQ(ierr);
3031   ierr = VecCreateSeq(PETSC_COMM_SELF, n, &offdiagV);CHKERRQ(ierr);
3032   ierr = MatGetRowMax(mat->A, diagV,    diagIdx);CHKERRQ(ierr);
3033   ierr = MatGetRowMax(mat->B, offdiagV, offdiagIdx);CHKERRQ(ierr);
3034   ierr = VecGetArray(v,        &a);CHKERRQ(ierr);
3035   ierr = VecGetArray(diagV,    &diagA);CHKERRQ(ierr);
3036   ierr = VecGetArray(offdiagV, &offdiagA);CHKERRQ(ierr);
3037   for (r = 0; r < n; ++r) {
3038     if (PetscAbsScalar(diagA[r]) >= PetscAbsScalar(offdiagA[r])) {
3039       a[r]   = diagA[r];
3040       idx[r] = cstart + diagIdx[r];
3041     } else {
3042       a[r]   = offdiagA[r];
3043       idx[r] = cmap[offdiagIdx[r]];
3044     }
3045   }
3046   ierr = VecRestoreArray(v,        &a);CHKERRQ(ierr);
3047   ierr = VecRestoreArray(diagV,    &diagA);CHKERRQ(ierr);
3048   ierr = VecRestoreArray(offdiagV, &offdiagA);CHKERRQ(ierr);
3049   ierr = VecDestroy(&diagV);CHKERRQ(ierr);
3050   ierr = VecDestroy(&offdiagV);CHKERRQ(ierr);
3051   ierr = PetscFree2(diagIdx, offdiagIdx);CHKERRQ(ierr);
3052   PetscFunctionReturn(0);
3053 }
3054 
3055 #undef __FUNCT__
3056 #define __FUNCT__ "MatGetSeqNonzeroStructure_MPIAIJ"
3057 PetscErrorCode MatGetSeqNonzeroStructure_MPIAIJ(Mat mat,Mat *newmat)
3058 {
3059   PetscErrorCode ierr;
3060   Mat            *dummy;
3061 
3062   PetscFunctionBegin;
3063   ierr    = MatGetSubMatrix_MPIAIJ_All(mat,MAT_DO_NOT_GET_VALUES,MAT_INITIAL_MATRIX,&dummy);CHKERRQ(ierr);
3064   *newmat = *dummy;
3065   ierr    = PetscFree(dummy);CHKERRQ(ierr);
3066   PetscFunctionReturn(0);
3067 }
3068 
3069 extern PetscErrorCode  MatFDColoringApply_AIJ(Mat,MatFDColoring,Vec,MatStructure*,void*);
3070 
3071 #undef __FUNCT__
3072 #define __FUNCT__ "MatInvertBlockDiagonal_MPIAIJ"
3073 PetscErrorCode  MatInvertBlockDiagonal_MPIAIJ(Mat A,const PetscScalar **values)
3074 {
3075   Mat_MPIAIJ     *a = (Mat_MPIAIJ*) A->data;
3076   PetscErrorCode ierr;
3077 
3078   PetscFunctionBegin;
3079   ierr = MatInvertBlockDiagonal(a->A,values);CHKERRQ(ierr);
3080   PetscFunctionReturn(0);
3081 }
3082 
3083 #undef __FUNCT__
3084 #define __FUNCT__ "MatSetRandom_MPIAIJ"
3085 static PetscErrorCode  MatSetRandom_MPIAIJ(Mat x,PetscRandom rctx)
3086 {
3087   PetscErrorCode ierr;
3088   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)x->data;
3089 
3090   PetscFunctionBegin;
3091   ierr = MatSetRandom(aij->A,rctx);CHKERRQ(ierr);
3092   ierr = MatSetRandom(aij->B,rctx);CHKERRQ(ierr);
3093   ierr = MatAssemblyBegin(x,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
3094   ierr = MatAssemblyEnd(x,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
3095   PetscFunctionReturn(0);
3096 }
3097 
3098 /* -------------------------------------------------------------------*/
3099 static struct _MatOps MatOps_Values = {MatSetValues_MPIAIJ,
3100        MatGetRow_MPIAIJ,
3101        MatRestoreRow_MPIAIJ,
3102        MatMult_MPIAIJ,
3103 /* 4*/ MatMultAdd_MPIAIJ,
3104        MatMultTranspose_MPIAIJ,
3105        MatMultTransposeAdd_MPIAIJ,
3106 #if defined(PETSC_HAVE_PBGL)
3107        MatSolve_MPIAIJ,
3108 #else
3109        0,
3110 #endif
3111        0,
3112        0,
3113 /*10*/ 0,
3114        0,
3115        0,
3116        MatSOR_MPIAIJ,
3117        MatTranspose_MPIAIJ,
3118 /*15*/ MatGetInfo_MPIAIJ,
3119        MatEqual_MPIAIJ,
3120        MatGetDiagonal_MPIAIJ,
3121        MatDiagonalScale_MPIAIJ,
3122        MatNorm_MPIAIJ,
3123 /*20*/ MatAssemblyBegin_MPIAIJ,
3124        MatAssemblyEnd_MPIAIJ,
3125        MatSetOption_MPIAIJ,
3126        MatZeroEntries_MPIAIJ,
3127 /*24*/ MatZeroRows_MPIAIJ,
3128        0,
3129 #if defined(PETSC_HAVE_PBGL)
3130        0,
3131 #else
3132        0,
3133 #endif
3134        0,
3135        0,
3136 /*29*/ MatSetUp_MPIAIJ,
3137 #if defined(PETSC_HAVE_PBGL)
3138        0,
3139 #else
3140        0,
3141 #endif
3142        0,
3143        0,
3144        0,
3145 /*34*/ MatDuplicate_MPIAIJ,
3146        0,
3147        0,
3148        0,
3149        0,
3150 /*39*/ MatAXPY_MPIAIJ,
3151        MatGetSubMatrices_MPIAIJ,
3152        MatIncreaseOverlap_MPIAIJ,
3153        MatGetValues_MPIAIJ,
3154        MatCopy_MPIAIJ,
3155 /*44*/ MatGetRowMax_MPIAIJ,
3156        MatScale_MPIAIJ,
3157        0,
3158        0,
3159        MatZeroRowsColumns_MPIAIJ,
3160 /*49*/ MatSetRandom_MPIAIJ,
3161        0,
3162        0,
3163        0,
3164        0,
3165 /*54*/ MatFDColoringCreate_MPIAIJ,
3166        0,
3167        MatSetUnfactored_MPIAIJ,
3168        MatPermute_MPIAIJ,
3169        0,
3170 /*59*/ MatGetSubMatrix_MPIAIJ,
3171        MatDestroy_MPIAIJ,
3172        MatView_MPIAIJ,
3173        0,
3174        MatMatMatMult_MPIAIJ_MPIAIJ_MPIAIJ,
3175 /*64*/ MatMatMatMultSymbolic_MPIAIJ_MPIAIJ_MPIAIJ,
3176        MatMatMatMultNumeric_MPIAIJ_MPIAIJ_MPIAIJ,
3177        0,
3178        0,
3179        0,
3180 /*69*/ MatGetRowMaxAbs_MPIAIJ,
3181        MatGetRowMinAbs_MPIAIJ,
3182        0,
3183        MatSetColoring_MPIAIJ,
3184        0,
3185        MatSetValuesAdifor_MPIAIJ,
3186 /*75*/ MatFDColoringApply_AIJ,
3187        0,
3188        0,
3189        0,
3190        MatFindZeroDiagonals_MPIAIJ,
3191 /*80*/ 0,
3192        0,
3193        0,
3194 /*83*/ MatLoad_MPIAIJ,
3195        0,
3196        0,
3197        0,
3198        0,
3199        0,
3200 /*89*/ MatMatMult_MPIAIJ_MPIAIJ,
3201        MatMatMultSymbolic_MPIAIJ_MPIAIJ,
3202        MatMatMultNumeric_MPIAIJ_MPIAIJ,
3203        MatPtAP_MPIAIJ_MPIAIJ,
3204        MatPtAPSymbolic_MPIAIJ_MPIAIJ,
3205 /*94*/ MatPtAPNumeric_MPIAIJ_MPIAIJ,
3206        0,
3207        0,
3208        0,
3209        0,
3210 /*99*/ 0,
3211        0,
3212        0,
3213        MatConjugate_MPIAIJ,
3214        0,
3215 /*104*/MatSetValuesRow_MPIAIJ,
3216        MatRealPart_MPIAIJ,
3217        MatImaginaryPart_MPIAIJ,
3218        0,
3219        0,
3220 /*109*/0,
3221        MatGetRedundantMatrix_MPIAIJ,
3222        MatGetRowMin_MPIAIJ,
3223        0,
3224        0,
3225 /*114*/MatGetSeqNonzeroStructure_MPIAIJ,
3226        0,
3227        0,
3228        0,
3229        0,
3230 /*119*/0,
3231        0,
3232        0,
3233        0,
3234        MatGetMultiProcBlock_MPIAIJ,
3235 /*124*/MatFindNonzeroRows_MPIAIJ,
3236        MatGetColumnNorms_MPIAIJ,
3237        MatInvertBlockDiagonal_MPIAIJ,
3238        0,
3239        MatGetSubMatricesParallel_MPIAIJ,
3240 /*129*/0,
3241        MatTransposeMatMult_MPIAIJ_MPIAIJ,
3242        MatTransposeMatMultSymbolic_MPIAIJ_MPIAIJ,
3243        MatTransposeMatMultNumeric_MPIAIJ_MPIAIJ,
3244        0,
3245 /*134*/0,
3246        0,
3247        0,
3248        0,
3249        0
3250 };
3251 
3252 /* ----------------------------------------------------------------------------------------*/
3253 
3254 #undef __FUNCT__
3255 #define __FUNCT__ "MatStoreValues_MPIAIJ"
3256 PetscErrorCode  MatStoreValues_MPIAIJ(Mat mat)
3257 {
3258   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
3259   PetscErrorCode ierr;
3260 
3261   PetscFunctionBegin;
3262   ierr = MatStoreValues(aij->A);CHKERRQ(ierr);
3263   ierr = MatStoreValues(aij->B);CHKERRQ(ierr);
3264   PetscFunctionReturn(0);
3265 }
3266 
3267 #undef __FUNCT__
3268 #define __FUNCT__ "MatRetrieveValues_MPIAIJ"
3269 PetscErrorCode  MatRetrieveValues_MPIAIJ(Mat mat)
3270 {
3271   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
3272   PetscErrorCode ierr;
3273 
3274   PetscFunctionBegin;
3275   ierr = MatRetrieveValues(aij->A);CHKERRQ(ierr);
3276   ierr = MatRetrieveValues(aij->B);CHKERRQ(ierr);
3277   PetscFunctionReturn(0);
3278 }
3279 
3280 #undef __FUNCT__
3281 #define __FUNCT__ "MatMPIAIJSetPreallocation_MPIAIJ"
3282 PetscErrorCode  MatMPIAIJSetPreallocation_MPIAIJ(Mat B,PetscInt d_nz,const PetscInt d_nnz[],PetscInt o_nz,const PetscInt o_nnz[])
3283 {
3284   Mat_MPIAIJ     *b;
3285   PetscErrorCode ierr;
3286   PetscInt       i;
3287   PetscBool      d_realalloc = PETSC_FALSE,o_realalloc = PETSC_FALSE;
3288 
3289   PetscFunctionBegin;
3290   if (d_nz >= 0 || d_nnz) d_realalloc = PETSC_TRUE;
3291   if (o_nz >= 0 || o_nnz) o_realalloc = PETSC_TRUE;
3292   if (d_nz == PETSC_DEFAULT || d_nz == PETSC_DECIDE) d_nz = 5;
3293   if (o_nz == PETSC_DEFAULT || o_nz == PETSC_DECIDE) o_nz = 2;
3294   if (d_nz < 0) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"d_nz cannot be less than 0: value %D",d_nz);
3295   if (o_nz < 0) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"o_nz cannot be less than 0: value %D",o_nz);
3296 
3297   ierr = PetscLayoutSetUp(B->rmap);CHKERRQ(ierr);
3298   ierr = PetscLayoutSetUp(B->cmap);CHKERRQ(ierr);
3299   if (d_nnz) {
3300     for (i=0; i<B->rmap->n; i++) {
3301       if (d_nnz[i] < 0) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"d_nnz cannot be less than 0: local row %D value %D",i,d_nnz[i]);
3302     }
3303   }
3304   if (o_nnz) {
3305     for (i=0; i<B->rmap->n; i++) {
3306       if (o_nnz[i] < 0) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"o_nnz cannot be less than 0: local row %D value %D",i,o_nnz[i]);
3307     }
3308   }
3309   b = (Mat_MPIAIJ*)B->data;
3310 
3311   if (!B->preallocated) {
3312     /* Explicitly create 2 MATSEQAIJ matrices. */
3313     ierr = MatCreate(PETSC_COMM_SELF,&b->A);CHKERRQ(ierr);
3314     ierr = MatSetSizes(b->A,B->rmap->n,B->cmap->n,B->rmap->n,B->cmap->n);CHKERRQ(ierr);
3315     ierr = MatSetBlockSizes(b->A,B->rmap->bs,B->cmap->bs);CHKERRQ(ierr);
3316     ierr = MatSetType(b->A,MATSEQAIJ);CHKERRQ(ierr);
3317     ierr = PetscLogObjectParent(B,b->A);CHKERRQ(ierr);
3318     ierr = MatCreate(PETSC_COMM_SELF,&b->B);CHKERRQ(ierr);
3319     ierr = MatSetSizes(b->B,B->rmap->n,B->cmap->N,B->rmap->n,B->cmap->N);CHKERRQ(ierr);
3320     ierr = MatSetBlockSizes(b->B,B->rmap->bs,B->cmap->bs);CHKERRQ(ierr);
3321     ierr = MatSetType(b->B,MATSEQAIJ);CHKERRQ(ierr);
3322     ierr = PetscLogObjectParent(B,b->B);CHKERRQ(ierr);
3323   }
3324 
3325   ierr = MatSeqAIJSetPreallocation(b->A,d_nz,d_nnz);CHKERRQ(ierr);
3326   ierr = MatSeqAIJSetPreallocation(b->B,o_nz,o_nnz);CHKERRQ(ierr);
3327   /* Do not error if the user did not give real preallocation information. Ugly because this would overwrite a previous user call to MatSetOption(). */
3328   if (!d_realalloc) {ierr = MatSetOption(b->A,MAT_NEW_NONZERO_ALLOCATION_ERR,PETSC_FALSE);CHKERRQ(ierr);}
3329   if (!o_realalloc) {ierr = MatSetOption(b->B,MAT_NEW_NONZERO_ALLOCATION_ERR,PETSC_FALSE);CHKERRQ(ierr);}
3330   B->preallocated = PETSC_TRUE;
3331   PetscFunctionReturn(0);
3332 }
3333 
3334 #undef __FUNCT__
3335 #define __FUNCT__ "MatDuplicate_MPIAIJ"
3336 PetscErrorCode MatDuplicate_MPIAIJ(Mat matin,MatDuplicateOption cpvalues,Mat *newmat)
3337 {
3338   Mat            mat;
3339   Mat_MPIAIJ     *a,*oldmat = (Mat_MPIAIJ*)matin->data;
3340   PetscErrorCode ierr;
3341 
3342   PetscFunctionBegin;
3343   *newmat = 0;
3344   ierr    = MatCreate(PetscObjectComm((PetscObject)matin),&mat);CHKERRQ(ierr);
3345   ierr    = MatSetSizes(mat,matin->rmap->n,matin->cmap->n,matin->rmap->N,matin->cmap->N);CHKERRQ(ierr);
3346   ierr    = MatSetBlockSizes(mat,matin->rmap->bs,matin->cmap->bs);CHKERRQ(ierr);
3347   ierr    = MatSetType(mat,((PetscObject)matin)->type_name);CHKERRQ(ierr);
3348   ierr    = PetscMemcpy(mat->ops,matin->ops,sizeof(struct _MatOps));CHKERRQ(ierr);
3349   a       = (Mat_MPIAIJ*)mat->data;
3350 
3351   mat->factortype   = matin->factortype;
3352   mat->rmap->bs     = matin->rmap->bs;
3353   mat->cmap->bs     = matin->cmap->bs;
3354   mat->assembled    = PETSC_TRUE;
3355   mat->insertmode   = NOT_SET_VALUES;
3356   mat->preallocated = PETSC_TRUE;
3357 
3358   a->size         = oldmat->size;
3359   a->rank         = oldmat->rank;
3360   a->donotstash   = oldmat->donotstash;
3361   a->roworiented  = oldmat->roworiented;
3362   a->rowindices   = 0;
3363   a->rowvalues    = 0;
3364   a->getrowactive = PETSC_FALSE;
3365 
3366   ierr = PetscLayoutReference(matin->rmap,&mat->rmap);CHKERRQ(ierr);
3367   ierr = PetscLayoutReference(matin->cmap,&mat->cmap);CHKERRQ(ierr);
3368 
3369   if (oldmat->colmap) {
3370 #if defined(PETSC_USE_CTABLE)
3371     ierr = PetscTableCreateCopy(oldmat->colmap,&a->colmap);CHKERRQ(ierr);
3372 #else
3373     ierr = PetscMalloc((mat->cmap->N)*sizeof(PetscInt),&a->colmap);CHKERRQ(ierr);
3374     ierr = PetscLogObjectMemory(mat,(mat->cmap->N)*sizeof(PetscInt));CHKERRQ(ierr);
3375     ierr = PetscMemcpy(a->colmap,oldmat->colmap,(mat->cmap->N)*sizeof(PetscInt));CHKERRQ(ierr);
3376 #endif
3377   } else a->colmap = 0;
3378   if (oldmat->garray) {
3379     PetscInt len;
3380     len  = oldmat->B->cmap->n;
3381     ierr = PetscMalloc((len+1)*sizeof(PetscInt),&a->garray);CHKERRQ(ierr);
3382     ierr = PetscLogObjectMemory(mat,len*sizeof(PetscInt));CHKERRQ(ierr);
3383     if (len) { ierr = PetscMemcpy(a->garray,oldmat->garray,len*sizeof(PetscInt));CHKERRQ(ierr); }
3384   } else a->garray = 0;
3385 
3386   ierr    = VecDuplicate(oldmat->lvec,&a->lvec);CHKERRQ(ierr);
3387   ierr    = PetscLogObjectParent(mat,a->lvec);CHKERRQ(ierr);
3388   ierr    = VecScatterCopy(oldmat->Mvctx,&a->Mvctx);CHKERRQ(ierr);
3389   ierr    = PetscLogObjectParent(mat,a->Mvctx);CHKERRQ(ierr);
3390   ierr    = MatDuplicate(oldmat->A,cpvalues,&a->A);CHKERRQ(ierr);
3391   ierr    = PetscLogObjectParent(mat,a->A);CHKERRQ(ierr);
3392   ierr    = MatDuplicate(oldmat->B,cpvalues,&a->B);CHKERRQ(ierr);
3393   ierr    = PetscLogObjectParent(mat,a->B);CHKERRQ(ierr);
3394   ierr    = PetscFunctionListDuplicate(((PetscObject)matin)->qlist,&((PetscObject)mat)->qlist);CHKERRQ(ierr);
3395   *newmat = mat;
3396   PetscFunctionReturn(0);
3397 }
3398 
3399 
3400 
3401 #undef __FUNCT__
3402 #define __FUNCT__ "MatLoad_MPIAIJ"
3403 PetscErrorCode MatLoad_MPIAIJ(Mat newMat, PetscViewer viewer)
3404 {
3405   PetscScalar    *vals,*svals;
3406   MPI_Comm       comm;
3407   PetscErrorCode ierr;
3408   PetscMPIInt    rank,size,tag = ((PetscObject)viewer)->tag;
3409   PetscInt       i,nz,j,rstart,rend,mmax,maxnz = 0,grows,gcols;
3410   PetscInt       header[4],*rowlengths = 0,M,N,m,*cols;
3411   PetscInt       *ourlens = NULL,*procsnz = NULL,*offlens = NULL,jj,*mycols,*smycols;
3412   PetscInt       cend,cstart,n,*rowners,sizesset=1;
3413   int            fd;
3414   PetscInt       bs = 1;
3415 
3416   PetscFunctionBegin;
3417   ierr = PetscObjectGetComm((PetscObject)viewer,&comm);CHKERRQ(ierr);
3418   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
3419   ierr = MPI_Comm_rank(comm,&rank);CHKERRQ(ierr);
3420   if (!rank) {
3421     ierr = PetscViewerBinaryGetDescriptor(viewer,&fd);CHKERRQ(ierr);
3422     ierr = PetscBinaryRead(fd,(char*)header,4,PETSC_INT);CHKERRQ(ierr);
3423     if (header[0] != MAT_FILE_CLASSID) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_FILE_UNEXPECTED,"not matrix object");
3424   }
3425 
3426   ierr = PetscOptionsBegin(comm,NULL,"Options for loading SEQAIJ matrix","Mat");CHKERRQ(ierr);
3427   ierr = PetscOptionsInt("-matload_block_size","Set the blocksize used to store the matrix","MatLoad",bs,&bs,NULL);CHKERRQ(ierr);
3428   ierr = PetscOptionsEnd();CHKERRQ(ierr);
3429 
3430   if (newMat->rmap->n < 0 && newMat->rmap->N < 0 && newMat->cmap->n < 0 && newMat->cmap->N < 0) sizesset = 0;
3431 
3432   ierr = MPI_Bcast(header+1,3,MPIU_INT,0,comm);CHKERRQ(ierr);
3433   M    = header[1]; N = header[2];
3434   /* If global rows/cols are set to PETSC_DECIDE, set it to the sizes given in the file */
3435   if (sizesset && newMat->rmap->N < 0) newMat->rmap->N = M;
3436   if (sizesset && newMat->cmap->N < 0) newMat->cmap->N = N;
3437 
3438   /* If global sizes are set, check if they are consistent with that given in the file */
3439   if (sizesset) {
3440     ierr = MatGetSize(newMat,&grows,&gcols);CHKERRQ(ierr);
3441   }
3442   if (sizesset && newMat->rmap->N != grows) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_FILE_UNEXPECTED, "Inconsistent # of rows:Matrix in file has (%d) and input matrix has (%d)",M,grows);
3443   if (sizesset && newMat->cmap->N != gcols) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_FILE_UNEXPECTED, "Inconsistent # of cols:Matrix in file has (%d) and input matrix has (%d)",N,gcols);
3444 
3445   /* determine ownership of all (block) rows */
3446   if (M%bs) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_FILE_UNEXPECTED, "Inconsistent # of rows (%d) and block size (%d)",M,bs);
3447   if (newMat->rmap->n < 0) m = bs*((M/bs)/size + (((M/bs) % size) > rank));    /* PETSC_DECIDE */
3448   else m = newMat->rmap->n; /* Set by user */
3449 
3450   ierr = PetscMalloc((size+1)*sizeof(PetscInt),&rowners);CHKERRQ(ierr);
3451   ierr = MPI_Allgather(&m,1,MPIU_INT,rowners+1,1,MPIU_INT,comm);CHKERRQ(ierr);
3452 
3453   /* First process needs enough room for process with most rows */
3454   if (!rank) {
3455     mmax = rowners[1];
3456     for (i=2; i<=size; i++) {
3457       mmax = PetscMax(mmax, rowners[i]);
3458     }
3459   } else mmax = m;
3460 
3461   rowners[0] = 0;
3462   for (i=2; i<=size; i++) {
3463     rowners[i] += rowners[i-1];
3464   }
3465   rstart = rowners[rank];
3466   rend   = rowners[rank+1];
3467 
3468   /* distribute row lengths to all processors */
3469   ierr = PetscMalloc2(mmax,PetscInt,&ourlens,mmax,PetscInt,&offlens);CHKERRQ(ierr);
3470   if (!rank) {
3471     ierr = PetscBinaryRead(fd,ourlens,m,PETSC_INT);CHKERRQ(ierr);
3472     ierr = PetscMalloc(mmax*sizeof(PetscInt),&rowlengths);CHKERRQ(ierr);
3473     ierr = PetscMalloc(size*sizeof(PetscInt),&procsnz);CHKERRQ(ierr);
3474     ierr = PetscMemzero(procsnz,size*sizeof(PetscInt));CHKERRQ(ierr);
3475     for (j=0; j<m; j++) {
3476       procsnz[0] += ourlens[j];
3477     }
3478     for (i=1; i<size; i++) {
3479       ierr = PetscBinaryRead(fd,rowlengths,rowners[i+1]-rowners[i],PETSC_INT);CHKERRQ(ierr);
3480       /* calculate the number of nonzeros on each processor */
3481       for (j=0; j<rowners[i+1]-rowners[i]; j++) {
3482         procsnz[i] += rowlengths[j];
3483       }
3484       ierr = MPIULong_Send(rowlengths,rowners[i+1]-rowners[i],MPIU_INT,i,tag,comm);CHKERRQ(ierr);
3485     }
3486     ierr = PetscFree(rowlengths);CHKERRQ(ierr);
3487   } else {
3488     ierr = MPIULong_Recv(ourlens,m,MPIU_INT,0,tag,comm);CHKERRQ(ierr);
3489   }
3490 
3491   if (!rank) {
3492     /* determine max buffer needed and allocate it */
3493     maxnz = 0;
3494     for (i=0; i<size; i++) {
3495       maxnz = PetscMax(maxnz,procsnz[i]);
3496     }
3497     ierr = PetscMalloc(maxnz*sizeof(PetscInt),&cols);CHKERRQ(ierr);
3498 
3499     /* read in my part of the matrix column indices  */
3500     nz   = procsnz[0];
3501     ierr = PetscMalloc(nz*sizeof(PetscInt),&mycols);CHKERRQ(ierr);
3502     ierr = PetscBinaryRead(fd,mycols,nz,PETSC_INT);CHKERRQ(ierr);
3503 
3504     /* read in every one elses and ship off */
3505     for (i=1; i<size; i++) {
3506       nz   = procsnz[i];
3507       ierr = PetscBinaryRead(fd,cols,nz,PETSC_INT);CHKERRQ(ierr);
3508       ierr = MPIULong_Send(cols,nz,MPIU_INT,i,tag,comm);CHKERRQ(ierr);
3509     }
3510     ierr = PetscFree(cols);CHKERRQ(ierr);
3511   } else {
3512     /* determine buffer space needed for message */
3513     nz = 0;
3514     for (i=0; i<m; i++) {
3515       nz += ourlens[i];
3516     }
3517     ierr = PetscMalloc(nz*sizeof(PetscInt),&mycols);CHKERRQ(ierr);
3518 
3519     /* receive message of column indices*/
3520     ierr = MPIULong_Recv(mycols,nz,MPIU_INT,0,tag,comm);CHKERRQ(ierr);
3521   }
3522 
3523   /* determine column ownership if matrix is not square */
3524   if (N != M) {
3525     if (newMat->cmap->n < 0) n = N/size + ((N % size) > rank);
3526     else n = newMat->cmap->n;
3527     ierr   = MPI_Scan(&n,&cend,1,MPIU_INT,MPI_SUM,comm);CHKERRQ(ierr);
3528     cstart = cend - n;
3529   } else {
3530     cstart = rstart;
3531     cend   = rend;
3532     n      = cend - cstart;
3533   }
3534 
3535   /* loop over local rows, determining number of off diagonal entries */
3536   ierr = PetscMemzero(offlens,m*sizeof(PetscInt));CHKERRQ(ierr);
3537   jj   = 0;
3538   for (i=0; i<m; i++) {
3539     for (j=0; j<ourlens[i]; j++) {
3540       if (mycols[jj] < cstart || mycols[jj] >= cend) offlens[i]++;
3541       jj++;
3542     }
3543   }
3544 
3545   for (i=0; i<m; i++) {
3546     ourlens[i] -= offlens[i];
3547   }
3548   if (!sizesset) {
3549     ierr = MatSetSizes(newMat,m,n,M,N);CHKERRQ(ierr);
3550   }
3551 
3552   if (bs > 1) {ierr = MatSetBlockSize(newMat,bs);CHKERRQ(ierr);}
3553 
3554   ierr = MatMPIAIJSetPreallocation(newMat,0,ourlens,0,offlens);CHKERRQ(ierr);
3555 
3556   for (i=0; i<m; i++) {
3557     ourlens[i] += offlens[i];
3558   }
3559 
3560   if (!rank) {
3561     ierr = PetscMalloc((maxnz+1)*sizeof(PetscScalar),&vals);CHKERRQ(ierr);
3562 
3563     /* read in my part of the matrix numerical values  */
3564     nz   = procsnz[0];
3565     ierr = PetscBinaryRead(fd,vals,nz,PETSC_SCALAR);CHKERRQ(ierr);
3566 
3567     /* insert into matrix */
3568     jj      = rstart;
3569     smycols = mycols;
3570     svals   = vals;
3571     for (i=0; i<m; i++) {
3572       ierr     = MatSetValues_MPIAIJ(newMat,1,&jj,ourlens[i],smycols,svals,INSERT_VALUES);CHKERRQ(ierr);
3573       smycols += ourlens[i];
3574       svals   += ourlens[i];
3575       jj++;
3576     }
3577 
3578     /* read in other processors and ship out */
3579     for (i=1; i<size; i++) {
3580       nz   = procsnz[i];
3581       ierr = PetscBinaryRead(fd,vals,nz,PETSC_SCALAR);CHKERRQ(ierr);
3582       ierr = MPIULong_Send(vals,nz,MPIU_SCALAR,i,((PetscObject)newMat)->tag,comm);CHKERRQ(ierr);
3583     }
3584     ierr = PetscFree(procsnz);CHKERRQ(ierr);
3585   } else {
3586     /* receive numeric values */
3587     ierr = PetscMalloc((nz+1)*sizeof(PetscScalar),&vals);CHKERRQ(ierr);
3588 
3589     /* receive message of values*/
3590     ierr = MPIULong_Recv(vals,nz,MPIU_SCALAR,0,((PetscObject)newMat)->tag,comm);CHKERRQ(ierr);
3591 
3592     /* insert into matrix */
3593     jj      = rstart;
3594     smycols = mycols;
3595     svals   = vals;
3596     for (i=0; i<m; i++) {
3597       ierr     = MatSetValues_MPIAIJ(newMat,1,&jj,ourlens[i],smycols,svals,INSERT_VALUES);CHKERRQ(ierr);
3598       smycols += ourlens[i];
3599       svals   += ourlens[i];
3600       jj++;
3601     }
3602   }
3603   ierr = PetscFree2(ourlens,offlens);CHKERRQ(ierr);
3604   ierr = PetscFree(vals);CHKERRQ(ierr);
3605   ierr = PetscFree(mycols);CHKERRQ(ierr);
3606   ierr = PetscFree(rowners);CHKERRQ(ierr);
3607   ierr = MatAssemblyBegin(newMat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
3608   ierr = MatAssemblyEnd(newMat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
3609   PetscFunctionReturn(0);
3610 }
3611 
3612 #undef __FUNCT__
3613 #define __FUNCT__ "MatGetSubMatrix_MPIAIJ"
3614 PetscErrorCode MatGetSubMatrix_MPIAIJ(Mat mat,IS isrow,IS iscol,MatReuse call,Mat *newmat)
3615 {
3616   PetscErrorCode ierr;
3617   IS             iscol_local;
3618   PetscInt       csize;
3619 
3620   PetscFunctionBegin;
3621   ierr = ISGetLocalSize(iscol,&csize);CHKERRQ(ierr);
3622   if (call == MAT_REUSE_MATRIX) {
3623     ierr = PetscObjectQuery((PetscObject)*newmat,"ISAllGather",(PetscObject*)&iscol_local);CHKERRQ(ierr);
3624     if (!iscol_local) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"Submatrix passed in was not used before, cannot reuse");
3625   } else {
3626     PetscInt cbs;
3627     ierr = ISGetBlockSize(iscol,&cbs);CHKERRQ(ierr);
3628     ierr = ISAllGather(iscol,&iscol_local);CHKERRQ(ierr);
3629     ierr = ISSetBlockSize(iscol_local,cbs);CHKERRQ(ierr);
3630   }
3631   ierr = MatGetSubMatrix_MPIAIJ_Private(mat,isrow,iscol_local,csize,call,newmat);CHKERRQ(ierr);
3632   if (call == MAT_INITIAL_MATRIX) {
3633     ierr = PetscObjectCompose((PetscObject)*newmat,"ISAllGather",(PetscObject)iscol_local);CHKERRQ(ierr);
3634     ierr = ISDestroy(&iscol_local);CHKERRQ(ierr);
3635   }
3636   PetscFunctionReturn(0);
3637 }
3638 
3639 extern PetscErrorCode MatGetSubMatrices_MPIAIJ_Local(Mat,PetscInt,const IS[],const IS[],MatReuse,PetscBool*,Mat*);
3640 #undef __FUNCT__
3641 #define __FUNCT__ "MatGetSubMatrix_MPIAIJ_Private"
3642 /*
3643     Not great since it makes two copies of the submatrix, first an SeqAIJ
3644   in local and then by concatenating the local matrices the end result.
3645   Writing it directly would be much like MatGetSubMatrices_MPIAIJ()
3646 
3647   Note: This requires a sequential iscol with all indices.
3648 */
3649 PetscErrorCode MatGetSubMatrix_MPIAIJ_Private(Mat mat,IS isrow,IS iscol,PetscInt csize,MatReuse call,Mat *newmat)
3650 {
3651   PetscErrorCode ierr;
3652   PetscMPIInt    rank,size;
3653   PetscInt       i,m,n,rstart,row,rend,nz,*cwork,j,bs,cbs;
3654   PetscInt       *ii,*jj,nlocal,*dlens,*olens,dlen,olen,jend,mglobal,ncol;
3655   PetscBool      allcolumns, colflag;
3656   Mat            M,Mreuse;
3657   MatScalar      *vwork,*aa;
3658   MPI_Comm       comm;
3659   Mat_SeqAIJ     *aij;
3660 
3661   PetscFunctionBegin;
3662   ierr = PetscObjectGetComm((PetscObject)mat,&comm);CHKERRQ(ierr);
3663   ierr = MPI_Comm_rank(comm,&rank);CHKERRQ(ierr);
3664   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
3665 
3666   ierr = ISIdentity(iscol,&colflag);CHKERRQ(ierr);
3667   ierr = ISGetLocalSize(iscol,&ncol);CHKERRQ(ierr);
3668   if (colflag && ncol == mat->cmap->N) {
3669     allcolumns = PETSC_TRUE;
3670   } else {
3671     allcolumns = PETSC_FALSE;
3672   }
3673   if (call ==  MAT_REUSE_MATRIX) {
3674     ierr = PetscObjectQuery((PetscObject)*newmat,"SubMatrix",(PetscObject*)&Mreuse);CHKERRQ(ierr);
3675     if (!Mreuse) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"Submatrix passed in was not used before, cannot reuse");
3676     ierr = MatGetSubMatrices_MPIAIJ_Local(mat,1,&isrow,&iscol,MAT_REUSE_MATRIX,&allcolumns,&Mreuse);CHKERRQ(ierr);
3677   } else {
3678     ierr = MatGetSubMatrices_MPIAIJ_Local(mat,1,&isrow,&iscol,MAT_INITIAL_MATRIX,&allcolumns,&Mreuse);CHKERRQ(ierr);
3679   }
3680 
3681   /*
3682       m - number of local rows
3683       n - number of columns (same on all processors)
3684       rstart - first row in new global matrix generated
3685   */
3686   ierr = MatGetSize(Mreuse,&m,&n);CHKERRQ(ierr);
3687   ierr = MatGetBlockSizes(Mreuse,&bs,&cbs);CHKERRQ(ierr);
3688   if (call == MAT_INITIAL_MATRIX) {
3689     aij = (Mat_SeqAIJ*)(Mreuse)->data;
3690     ii  = aij->i;
3691     jj  = aij->j;
3692 
3693     /*
3694         Determine the number of non-zeros in the diagonal and off-diagonal
3695         portions of the matrix in order to do correct preallocation
3696     */
3697 
3698     /* first get start and end of "diagonal" columns */
3699     if (csize == PETSC_DECIDE) {
3700       ierr = ISGetSize(isrow,&mglobal);CHKERRQ(ierr);
3701       if (mglobal == n) { /* square matrix */
3702         nlocal = m;
3703       } else {
3704         nlocal = n/size + ((n % size) > rank);
3705       }
3706     } else {
3707       nlocal = csize;
3708     }
3709     ierr   = MPI_Scan(&nlocal,&rend,1,MPIU_INT,MPI_SUM,comm);CHKERRQ(ierr);
3710     rstart = rend - nlocal;
3711     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);
3712 
3713     /* next, compute all the lengths */
3714     ierr  = PetscMalloc((2*m+1)*sizeof(PetscInt),&dlens);CHKERRQ(ierr);
3715     olens = dlens + m;
3716     for (i=0; i<m; i++) {
3717       jend = ii[i+1] - ii[i];
3718       olen = 0;
3719       dlen = 0;
3720       for (j=0; j<jend; j++) {
3721         if (*jj < rstart || *jj >= rend) olen++;
3722         else dlen++;
3723         jj++;
3724       }
3725       olens[i] = olen;
3726       dlens[i] = dlen;
3727     }
3728     ierr = MatCreate(comm,&M);CHKERRQ(ierr);
3729     ierr = MatSetSizes(M,m,nlocal,PETSC_DECIDE,n);CHKERRQ(ierr);
3730     ierr = MatSetBlockSizes(M,bs,cbs);CHKERRQ(ierr);
3731     ierr = MatSetType(M,((PetscObject)mat)->type_name);CHKERRQ(ierr);
3732     ierr = MatMPIAIJSetPreallocation(M,0,dlens,0,olens);CHKERRQ(ierr);
3733     ierr = PetscFree(dlens);CHKERRQ(ierr);
3734   } else {
3735     PetscInt ml,nl;
3736 
3737     M    = *newmat;
3738     ierr = MatGetLocalSize(M,&ml,&nl);CHKERRQ(ierr);
3739     if (ml != m) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_SIZ,"Previous matrix must be same size/layout as request");
3740     ierr = MatZeroEntries(M);CHKERRQ(ierr);
3741     /*
3742          The next two lines are needed so we may call MatSetValues_MPIAIJ() below directly,
3743        rather than the slower MatSetValues().
3744     */
3745     M->was_assembled = PETSC_TRUE;
3746     M->assembled     = PETSC_FALSE;
3747   }
3748   ierr = MatGetOwnershipRange(M,&rstart,&rend);CHKERRQ(ierr);
3749   aij  = (Mat_SeqAIJ*)(Mreuse)->data;
3750   ii   = aij->i;
3751   jj   = aij->j;
3752   aa   = aij->a;
3753   for (i=0; i<m; i++) {
3754     row   = rstart + i;
3755     nz    = ii[i+1] - ii[i];
3756     cwork = jj;     jj += nz;
3757     vwork = aa;     aa += nz;
3758     ierr  = MatSetValues_MPIAIJ(M,1,&row,nz,cwork,vwork,INSERT_VALUES);CHKERRQ(ierr);
3759   }
3760 
3761   ierr    = MatAssemblyBegin(M,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
3762   ierr    = MatAssemblyEnd(M,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
3763   *newmat = M;
3764 
3765   /* save submatrix used in processor for next request */
3766   if (call ==  MAT_INITIAL_MATRIX) {
3767     ierr = PetscObjectCompose((PetscObject)M,"SubMatrix",(PetscObject)Mreuse);CHKERRQ(ierr);
3768     ierr = MatDestroy(&Mreuse);CHKERRQ(ierr);
3769   }
3770   PetscFunctionReturn(0);
3771 }
3772 
3773 #undef __FUNCT__
3774 #define __FUNCT__ "MatMPIAIJSetPreallocationCSR_MPIAIJ"
3775 PetscErrorCode  MatMPIAIJSetPreallocationCSR_MPIAIJ(Mat B,const PetscInt Ii[],const PetscInt J[],const PetscScalar v[])
3776 {
3777   PetscInt       m,cstart, cend,j,nnz,i,d;
3778   PetscInt       *d_nnz,*o_nnz,nnz_max = 0,rstart,ii;
3779   const PetscInt *JJ;
3780   PetscScalar    *values;
3781   PetscErrorCode ierr;
3782 
3783   PetscFunctionBegin;
3784   if (Ii[0]) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Ii[0] must be 0 it is %D",Ii[0]);
3785 
3786   ierr   = PetscLayoutSetUp(B->rmap);CHKERRQ(ierr);
3787   ierr   = PetscLayoutSetUp(B->cmap);CHKERRQ(ierr);
3788   m      = B->rmap->n;
3789   cstart = B->cmap->rstart;
3790   cend   = B->cmap->rend;
3791   rstart = B->rmap->rstart;
3792 
3793   ierr = PetscMalloc2(m,PetscInt,&d_nnz,m,PetscInt,&o_nnz);CHKERRQ(ierr);
3794 
3795 #if defined(PETSC_USE_DEBUGGING)
3796   for (i=0; i<m; i++) {
3797     nnz = Ii[i+1]- Ii[i];
3798     JJ  = J + Ii[i];
3799     if (nnz < 0) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Local row %D has a negative %D number of columns",i,nnz);
3800     if (nnz && (JJ[0] < 0)) SETERRRQ1(PETSC_ERR_ARG_WRONGSTATE,"Row %D starts with negative column index",i,j);
3801     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);
3802   }
3803 #endif
3804 
3805   for (i=0; i<m; i++) {
3806     nnz     = Ii[i+1]- Ii[i];
3807     JJ      = J + Ii[i];
3808     nnz_max = PetscMax(nnz_max,nnz);
3809     d       = 0;
3810     for (j=0; j<nnz; j++) {
3811       if (cstart <= JJ[j] && JJ[j] < cend) d++;
3812     }
3813     d_nnz[i] = d;
3814     o_nnz[i] = nnz - d;
3815   }
3816   ierr = MatMPIAIJSetPreallocation(B,0,d_nnz,0,o_nnz);CHKERRQ(ierr);
3817   ierr = PetscFree2(d_nnz,o_nnz);CHKERRQ(ierr);
3818 
3819   if (v) values = (PetscScalar*)v;
3820   else {
3821     ierr = PetscMalloc((nnz_max+1)*sizeof(PetscScalar),&values);CHKERRQ(ierr);
3822     ierr = PetscMemzero(values,nnz_max*sizeof(PetscScalar));CHKERRQ(ierr);
3823   }
3824 
3825   for (i=0; i<m; i++) {
3826     ii   = i + rstart;
3827     nnz  = Ii[i+1]- Ii[i];
3828     ierr = MatSetValues_MPIAIJ(B,1,&ii,nnz,J+Ii[i],values+(v ? Ii[i] : 0),INSERT_VALUES);CHKERRQ(ierr);
3829   }
3830   ierr = MatAssemblyBegin(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
3831   ierr = MatAssemblyEnd(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
3832 
3833   if (!v) {
3834     ierr = PetscFree(values);CHKERRQ(ierr);
3835   }
3836   ierr = MatSetOption(B,MAT_NEW_NONZERO_LOCATION_ERR,PETSC_TRUE);CHKERRQ(ierr);
3837   PetscFunctionReturn(0);
3838 }
3839 
3840 #undef __FUNCT__
3841 #define __FUNCT__ "MatMPIAIJSetPreallocationCSR"
3842 /*@
3843    MatMPIAIJSetPreallocationCSR - Allocates memory for a sparse parallel matrix in AIJ format
3844    (the default parallel PETSc format).
3845 
3846    Collective on MPI_Comm
3847 
3848    Input Parameters:
3849 +  B - the matrix
3850 .  i - the indices into j for the start of each local row (starts with zero)
3851 .  j - the column indices for each local row (starts with zero)
3852 -  v - optional values in the matrix
3853 
3854    Level: developer
3855 
3856    Notes:
3857        The i, j, and a arrays ARE copied by this routine into the internal format used by PETSc;
3858      thus you CANNOT change the matrix entries by changing the values of a[] after you have
3859      called this routine. Use MatCreateMPIAIJWithSplitArrays() to avoid needing to copy the arrays.
3860 
3861        The i and j indices are 0 based, and i indices are indices corresponding to the local j array.
3862 
3863        The format which is used for the sparse matrix input, is equivalent to a
3864     row-major ordering.. i.e for the following matrix, the input data expected is
3865     as shown:
3866 
3867         1 0 0
3868         2 0 3     P0
3869        -------
3870         4 5 6     P1
3871 
3872      Process0 [P0]: rows_owned=[0,1]
3873         i =  {0,1,3}  [size = nrow+1  = 2+1]
3874         j =  {0,0,2}  [size = nz = 6]
3875         v =  {1,2,3}  [size = nz = 6]
3876 
3877      Process1 [P1]: rows_owned=[2]
3878         i =  {0,3}    [size = nrow+1  = 1+1]
3879         j =  {0,1,2}  [size = nz = 6]
3880         v =  {4,5,6}  [size = nz = 6]
3881 
3882 .keywords: matrix, aij, compressed row, sparse, parallel
3883 
3884 .seealso: MatCreate(), MatCreateSeqAIJ(), MatSetValues(), MatMPIAIJSetPreallocation(), MatCreateAIJ(), MPIAIJ,
3885           MatCreateSeqAIJWithArrays(), MatCreateMPIAIJWithSplitArrays()
3886 @*/
3887 PetscErrorCode  MatMPIAIJSetPreallocationCSR(Mat B,const PetscInt i[],const PetscInt j[], const PetscScalar v[])
3888 {
3889   PetscErrorCode ierr;
3890 
3891   PetscFunctionBegin;
3892   ierr = PetscTryMethod(B,"MatMPIAIJSetPreallocationCSR_C",(Mat,const PetscInt[],const PetscInt[],const PetscScalar[]),(B,i,j,v));CHKERRQ(ierr);
3893   PetscFunctionReturn(0);
3894 }
3895 
3896 #undef __FUNCT__
3897 #define __FUNCT__ "MatMPIAIJSetPreallocation"
3898 /*@C
3899    MatMPIAIJSetPreallocation - Preallocates memory for a sparse parallel matrix in AIJ format
3900    (the default parallel PETSc format).  For good matrix assembly performance
3901    the user should preallocate the matrix storage by setting the parameters
3902    d_nz (or d_nnz) and o_nz (or o_nnz).  By setting these parameters accurately,
3903    performance can be increased by more than a factor of 50.
3904 
3905    Collective on MPI_Comm
3906 
3907    Input Parameters:
3908 +  A - the matrix
3909 .  d_nz  - number of nonzeros per row in DIAGONAL portion of local submatrix
3910            (same value is used for all local rows)
3911 .  d_nnz - array containing the number of nonzeros in the various rows of the
3912            DIAGONAL portion of the local submatrix (possibly different for each row)
3913            or NULL, if d_nz is used to specify the nonzero structure.
3914            The size of this array is equal to the number of local rows, i.e 'm'.
3915            For matrices that will be factored, you must leave room for (and set)
3916            the diagonal entry even if it is zero.
3917 .  o_nz  - number of nonzeros per row in the OFF-DIAGONAL portion of local
3918            submatrix (same value is used for all local rows).
3919 -  o_nnz - array containing the number of nonzeros in the various rows of the
3920            OFF-DIAGONAL portion of the local submatrix (possibly different for
3921            each row) or NULL, if o_nz is used to specify the nonzero
3922            structure. The size of this array is equal to the number
3923            of local rows, i.e 'm'.
3924 
3925    If the *_nnz parameter is given then the *_nz parameter is ignored
3926 
3927    The AIJ format (also called the Yale sparse matrix format or
3928    compressed row storage (CSR)), is fully compatible with standard Fortran 77
3929    storage.  The stored row and column indices begin with zero.
3930    See the <A href="../../docs/manual.pdf#nameddest=ch_mat">Mat chapter of the users manual</A> for details.
3931 
3932    The parallel matrix is partitioned such that the first m0 rows belong to
3933    process 0, the next m1 rows belong to process 1, the next m2 rows belong
3934    to process 2 etc.. where m0,m1,m2... are the input parameter 'm'.
3935 
3936    The DIAGONAL portion of the local submatrix of a processor can be defined
3937    as the submatrix which is obtained by extraction the part corresponding to
3938    the rows r1-r2 and columns c1-c2 of the global matrix, where r1 is the
3939    first row that belongs to the processor, r2 is the last row belonging to
3940    the this processor, and c1-c2 is range of indices of the local part of a
3941    vector suitable for applying the matrix to.  This is an mxn matrix.  In the
3942    common case of a square matrix, the row and column ranges are the same and
3943    the DIAGONAL part is also square. The remaining portion of the local
3944    submatrix (mxN) constitute the OFF-DIAGONAL portion.
3945 
3946    If o_nnz, d_nnz are specified, then o_nz, and d_nz are ignored.
3947 
3948    You can call MatGetInfo() to get information on how effective the preallocation was;
3949    for example the fields mallocs,nz_allocated,nz_used,nz_unneeded;
3950    You can also run with the option -info and look for messages with the string
3951    malloc in them to see if additional memory allocation was needed.
3952 
3953    Example usage:
3954 
3955    Consider the following 8x8 matrix with 34 non-zero values, that is
3956    assembled across 3 processors. Lets assume that proc0 owns 3 rows,
3957    proc1 owns 3 rows, proc2 owns 2 rows. This division can be shown
3958    as follows:
3959 
3960 .vb
3961             1  2  0  |  0  3  0  |  0  4
3962     Proc0   0  5  6  |  7  0  0  |  8  0
3963             9  0 10  | 11  0  0  | 12  0
3964     -------------------------------------
3965            13  0 14  | 15 16 17  |  0  0
3966     Proc1   0 18  0  | 19 20 21  |  0  0
3967             0  0  0  | 22 23  0  | 24  0
3968     -------------------------------------
3969     Proc2  25 26 27  |  0  0 28  | 29  0
3970            30  0  0  | 31 32 33  |  0 34
3971 .ve
3972 
3973    This can be represented as a collection of submatrices as:
3974 
3975 .vb
3976       A B C
3977       D E F
3978       G H I
3979 .ve
3980 
3981    Where the submatrices A,B,C are owned by proc0, D,E,F are
3982    owned by proc1, G,H,I are owned by proc2.
3983 
3984    The 'm' parameters for proc0,proc1,proc2 are 3,3,2 respectively.
3985    The 'n' parameters for proc0,proc1,proc2 are 3,3,2 respectively.
3986    The 'M','N' parameters are 8,8, and have the same values on all procs.
3987 
3988    The DIAGONAL submatrices corresponding to proc0,proc1,proc2 are
3989    submatrices [A], [E], [I] respectively. The OFF-DIAGONAL submatrices
3990    corresponding to proc0,proc1,proc2 are [BC], [DF], [GH] respectively.
3991    Internally, each processor stores the DIAGONAL part, and the OFF-DIAGONAL
3992    part as SeqAIJ matrices. for eg: proc1 will store [E] as a SeqAIJ
3993    matrix, ans [DF] as another SeqAIJ matrix.
3994 
3995    When d_nz, o_nz parameters are specified, d_nz storage elements are
3996    allocated for every row of the local diagonal submatrix, and o_nz
3997    storage locations are allocated for every row of the OFF-DIAGONAL submat.
3998    One way to choose d_nz and o_nz is to use the max nonzerors per local
3999    rows for each of the local DIAGONAL, and the OFF-DIAGONAL submatrices.
4000    In this case, the values of d_nz,o_nz are:
4001 .vb
4002      proc0 : dnz = 2, o_nz = 2
4003      proc1 : dnz = 3, o_nz = 2
4004      proc2 : dnz = 1, o_nz = 4
4005 .ve
4006    We are allocating m*(d_nz+o_nz) storage locations for every proc. This
4007    translates to 3*(2+2)=12 for proc0, 3*(3+2)=15 for proc1, 2*(1+4)=10
4008    for proc3. i.e we are using 12+15+10=37 storage locations to store
4009    34 values.
4010 
4011    When d_nnz, o_nnz parameters are specified, the storage is specified
4012    for every row, coresponding to both DIAGONAL and OFF-DIAGONAL submatrices.
4013    In the above case the values for d_nnz,o_nnz are:
4014 .vb
4015      proc0: d_nnz = [2,2,2] and o_nnz = [2,2,2]
4016      proc1: d_nnz = [3,3,2] and o_nnz = [2,1,1]
4017      proc2: d_nnz = [1,1]   and o_nnz = [4,4]
4018 .ve
4019    Here the space allocated is sum of all the above values i.e 34, and
4020    hence pre-allocation is perfect.
4021 
4022    Level: intermediate
4023 
4024 .keywords: matrix, aij, compressed row, sparse, parallel
4025 
4026 .seealso: MatCreate(), MatCreateSeqAIJ(), MatSetValues(), MatCreateAIJ(), MatMPIAIJSetPreallocationCSR(),
4027           MPIAIJ, MatGetInfo(), PetscSplitOwnership()
4028 @*/
4029 PetscErrorCode  MatMPIAIJSetPreallocation(Mat B,PetscInt d_nz,const PetscInt d_nnz[],PetscInt o_nz,const PetscInt o_nnz[])
4030 {
4031   PetscErrorCode ierr;
4032 
4033   PetscFunctionBegin;
4034   PetscValidHeaderSpecific(B,MAT_CLASSID,1);
4035   PetscValidType(B,1);
4036   ierr = PetscTryMethod(B,"MatMPIAIJSetPreallocation_C",(Mat,PetscInt,const PetscInt[],PetscInt,const PetscInt[]),(B,d_nz,d_nnz,o_nz,o_nnz));CHKERRQ(ierr);
4037   PetscFunctionReturn(0);
4038 }
4039 
4040 #undef __FUNCT__
4041 #define __FUNCT__ "MatCreateMPIAIJWithArrays"
4042 /*@
4043      MatCreateMPIAIJWithArrays - creates a MPI AIJ matrix using arrays that contain in standard
4044          CSR format the local rows.
4045 
4046    Collective on MPI_Comm
4047 
4048    Input Parameters:
4049 +  comm - MPI communicator
4050 .  m - number of local rows (Cannot be PETSC_DECIDE)
4051 .  n - This value should be the same as the local size used in creating the
4052        x vector for the matrix-vector product y = Ax. (or PETSC_DECIDE to have
4053        calculated if N is given) For square matrices n is almost always m.
4054 .  M - number of global rows (or PETSC_DETERMINE to have calculated if m is given)
4055 .  N - number of global columns (or PETSC_DETERMINE to have calculated if n is given)
4056 .   i - row indices
4057 .   j - column indices
4058 -   a - matrix values
4059 
4060    Output Parameter:
4061 .   mat - the matrix
4062 
4063    Level: intermediate
4064 
4065    Notes:
4066        The i, j, and a arrays ARE copied by this routine into the internal format used by PETSc;
4067      thus you CANNOT change the matrix entries by changing the values of a[] after you have
4068      called this routine. Use MatCreateMPIAIJWithSplitArrays() to avoid needing to copy the arrays.
4069 
4070        The i and j indices are 0 based, and i indices are indices corresponding to the local j array.
4071 
4072        The format which is used for the sparse matrix input, is equivalent to a
4073     row-major ordering.. i.e for the following matrix, the input data expected is
4074     as shown:
4075 
4076         1 0 0
4077         2 0 3     P0
4078        -------
4079         4 5 6     P1
4080 
4081      Process0 [P0]: rows_owned=[0,1]
4082         i =  {0,1,3}  [size = nrow+1  = 2+1]
4083         j =  {0,0,2}  [size = nz = 6]
4084         v =  {1,2,3}  [size = nz = 6]
4085 
4086      Process1 [P1]: rows_owned=[2]
4087         i =  {0,3}    [size = nrow+1  = 1+1]
4088         j =  {0,1,2}  [size = nz = 6]
4089         v =  {4,5,6}  [size = nz = 6]
4090 
4091 .keywords: matrix, aij, compressed row, sparse, parallel
4092 
4093 .seealso: MatCreate(), MatCreateSeqAIJ(), MatSetValues(), MatMPIAIJSetPreallocation(), MatMPIAIJSetPreallocationCSR(),
4094           MPIAIJ, MatCreateAIJ(), MatCreateMPIAIJWithSplitArrays()
4095 @*/
4096 PetscErrorCode  MatCreateMPIAIJWithArrays(MPI_Comm comm,PetscInt m,PetscInt n,PetscInt M,PetscInt N,const PetscInt i[],const PetscInt j[],const PetscScalar a[],Mat *mat)
4097 {
4098   PetscErrorCode ierr;
4099 
4100   PetscFunctionBegin;
4101   if (i[0]) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"i (row indices) must start with 0");
4102   if (m < 0) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"local number of rows (m) cannot be PETSC_DECIDE, or negative");
4103   ierr = MatCreate(comm,mat);CHKERRQ(ierr);
4104   ierr = MatSetSizes(*mat,m,n,M,N);CHKERRQ(ierr);
4105   /* ierr = MatSetBlockSizes(M,bs,cbs);CHKERRQ(ierr); */
4106   ierr = MatSetType(*mat,MATMPIAIJ);CHKERRQ(ierr);
4107   ierr = MatMPIAIJSetPreallocationCSR(*mat,i,j,a);CHKERRQ(ierr);
4108   PetscFunctionReturn(0);
4109 }
4110 
4111 #undef __FUNCT__
4112 #define __FUNCT__ "MatCreateAIJ"
4113 /*@C
4114    MatCreateAIJ - Creates a sparse parallel matrix in AIJ format
4115    (the default parallel PETSc format).  For good matrix assembly performance
4116    the user should preallocate the matrix storage by setting the parameters
4117    d_nz (or d_nnz) and o_nz (or o_nnz).  By setting these parameters accurately,
4118    performance can be increased by more than a factor of 50.
4119 
4120    Collective on MPI_Comm
4121 
4122    Input Parameters:
4123 +  comm - MPI communicator
4124 .  m - number of local rows (or PETSC_DECIDE to have calculated if M is given)
4125            This value should be the same as the local size used in creating the
4126            y vector for the matrix-vector product y = Ax.
4127 .  n - This value should be the same as the local size used in creating the
4128        x vector for the matrix-vector product y = Ax. (or PETSC_DECIDE to have
4129        calculated if N is given) For square matrices n is almost always m.
4130 .  M - number of global rows (or PETSC_DETERMINE to have calculated if m is given)
4131 .  N - number of global columns (or PETSC_DETERMINE to have calculated if n is given)
4132 .  d_nz  - number of nonzeros per row in DIAGONAL portion of local submatrix
4133            (same value is used for all local rows)
4134 .  d_nnz - array containing the number of nonzeros in the various rows of the
4135            DIAGONAL portion of the local submatrix (possibly different for each row)
4136            or NULL, if d_nz is used to specify the nonzero structure.
4137            The size of this array is equal to the number of local rows, i.e 'm'.
4138 .  o_nz  - number of nonzeros per row in the OFF-DIAGONAL portion of local
4139            submatrix (same value is used for all local rows).
4140 -  o_nnz - array containing the number of nonzeros in the various rows of the
4141            OFF-DIAGONAL portion of the local submatrix (possibly different for
4142            each row) or NULL, if o_nz is used to specify the nonzero
4143            structure. The size of this array is equal to the number
4144            of local rows, i.e 'm'.
4145 
4146    Output Parameter:
4147 .  A - the matrix
4148 
4149    It is recommended that one use the MatCreate(), MatSetType() and/or MatSetFromOptions(),
4150    MatXXXXSetPreallocation() paradgm instead of this routine directly.
4151    [MatXXXXSetPreallocation() is, for example, MatSeqAIJSetPreallocation]
4152 
4153    Notes:
4154    If the *_nnz parameter is given then the *_nz parameter is ignored
4155 
4156    m,n,M,N parameters specify the size of the matrix, and its partitioning across
4157    processors, while d_nz,d_nnz,o_nz,o_nnz parameters specify the approximate
4158    storage requirements for this matrix.
4159 
4160    If PETSC_DECIDE or  PETSC_DETERMINE is used for a particular argument on one
4161    processor than it must be used on all processors that share the object for
4162    that argument.
4163 
4164    The user MUST specify either the local or global matrix dimensions
4165    (possibly both).
4166 
4167    The parallel matrix is partitioned across processors such that the
4168    first m0 rows belong to process 0, the next m1 rows belong to
4169    process 1, the next m2 rows belong to process 2 etc.. where
4170    m0,m1,m2,.. are the input parameter 'm'. i.e each processor stores
4171    values corresponding to [m x N] submatrix.
4172 
4173    The columns are logically partitioned with the n0 columns belonging
4174    to 0th partition, the next n1 columns belonging to the next
4175    partition etc.. where n0,n1,n2... are the the input parameter 'n'.
4176 
4177    The DIAGONAL portion of the local submatrix on any given processor
4178    is the submatrix corresponding to the rows and columns m,n
4179    corresponding to the given processor. i.e diagonal matrix on
4180    process 0 is [m0 x n0], diagonal matrix on process 1 is [m1 x n1]
4181    etc. The remaining portion of the local submatrix [m x (N-n)]
4182    constitute the OFF-DIAGONAL portion. The example below better
4183    illustrates this concept.
4184 
4185    For a square global matrix we define each processor's diagonal portion
4186    to be its local rows and the corresponding columns (a square submatrix);
4187    each processor's off-diagonal portion encompasses the remainder of the
4188    local matrix (a rectangular submatrix).
4189 
4190    If o_nnz, d_nnz are specified, then o_nz, and d_nz are ignored.
4191 
4192    When calling this routine with a single process communicator, a matrix of
4193    type SEQAIJ is returned.  If a matrix of type MPIAIJ is desired for this
4194    type of communicator, use the construction mechanism:
4195      MatCreate(...,&A); MatSetType(A,MATMPIAIJ); MatSetSizes(A, m,n,M,N); MatMPIAIJSetPreallocation(A,...);
4196 
4197    By default, this format uses inodes (identical nodes) when possible.
4198    We search for consecutive rows with the same nonzero structure, thereby
4199    reusing matrix information to achieve increased efficiency.
4200 
4201    Options Database Keys:
4202 +  -mat_no_inode  - Do not use inodes
4203 .  -mat_inode_limit <limit> - Sets inode limit (max limit=5)
4204 -  -mat_aij_oneindex - Internally use indexing starting at 1
4205         rather than 0.  Note that when calling MatSetValues(),
4206         the user still MUST index entries starting at 0!
4207 
4208 
4209    Example usage:
4210 
4211    Consider the following 8x8 matrix with 34 non-zero values, that is
4212    assembled across 3 processors. Lets assume that proc0 owns 3 rows,
4213    proc1 owns 3 rows, proc2 owns 2 rows. This division can be shown
4214    as follows:
4215 
4216 .vb
4217             1  2  0  |  0  3  0  |  0  4
4218     Proc0   0  5  6  |  7  0  0  |  8  0
4219             9  0 10  | 11  0  0  | 12  0
4220     -------------------------------------
4221            13  0 14  | 15 16 17  |  0  0
4222     Proc1   0 18  0  | 19 20 21  |  0  0
4223             0  0  0  | 22 23  0  | 24  0
4224     -------------------------------------
4225     Proc2  25 26 27  |  0  0 28  | 29  0
4226            30  0  0  | 31 32 33  |  0 34
4227 .ve
4228 
4229    This can be represented as a collection of submatrices as:
4230 
4231 .vb
4232       A B C
4233       D E F
4234       G H I
4235 .ve
4236 
4237    Where the submatrices A,B,C are owned by proc0, D,E,F are
4238    owned by proc1, G,H,I are owned by proc2.
4239 
4240    The 'm' parameters for proc0,proc1,proc2 are 3,3,2 respectively.
4241    The 'n' parameters for proc0,proc1,proc2 are 3,3,2 respectively.
4242    The 'M','N' parameters are 8,8, and have the same values on all procs.
4243 
4244    The DIAGONAL submatrices corresponding to proc0,proc1,proc2 are
4245    submatrices [A], [E], [I] respectively. The OFF-DIAGONAL submatrices
4246    corresponding to proc0,proc1,proc2 are [BC], [DF], [GH] respectively.
4247    Internally, each processor stores the DIAGONAL part, and the OFF-DIAGONAL
4248    part as SeqAIJ matrices. for eg: proc1 will store [E] as a SeqAIJ
4249    matrix, ans [DF] as another SeqAIJ matrix.
4250 
4251    When d_nz, o_nz parameters are specified, d_nz storage elements are
4252    allocated for every row of the local diagonal submatrix, and o_nz
4253    storage locations are allocated for every row of the OFF-DIAGONAL submat.
4254    One way to choose d_nz and o_nz is to use the max nonzerors per local
4255    rows for each of the local DIAGONAL, and the OFF-DIAGONAL submatrices.
4256    In this case, the values of d_nz,o_nz are:
4257 .vb
4258      proc0 : dnz = 2, o_nz = 2
4259      proc1 : dnz = 3, o_nz = 2
4260      proc2 : dnz = 1, o_nz = 4
4261 .ve
4262    We are allocating m*(d_nz+o_nz) storage locations for every proc. This
4263    translates to 3*(2+2)=12 for proc0, 3*(3+2)=15 for proc1, 2*(1+4)=10
4264    for proc3. i.e we are using 12+15+10=37 storage locations to store
4265    34 values.
4266 
4267    When d_nnz, o_nnz parameters are specified, the storage is specified
4268    for every row, coresponding to both DIAGONAL and OFF-DIAGONAL submatrices.
4269    In the above case the values for d_nnz,o_nnz are:
4270 .vb
4271      proc0: d_nnz = [2,2,2] and o_nnz = [2,2,2]
4272      proc1: d_nnz = [3,3,2] and o_nnz = [2,1,1]
4273      proc2: d_nnz = [1,1]   and o_nnz = [4,4]
4274 .ve
4275    Here the space allocated is sum of all the above values i.e 34, and
4276    hence pre-allocation is perfect.
4277 
4278    Level: intermediate
4279 
4280 .keywords: matrix, aij, compressed row, sparse, parallel
4281 
4282 .seealso: MatCreate(), MatCreateSeqAIJ(), MatSetValues(), MatMPIAIJSetPreallocation(), MatMPIAIJSetPreallocationCSR(),
4283           MPIAIJ, MatCreateMPIAIJWithArrays()
4284 @*/
4285 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)
4286 {
4287   PetscErrorCode ierr;
4288   PetscMPIInt    size;
4289 
4290   PetscFunctionBegin;
4291   ierr = MatCreate(comm,A);CHKERRQ(ierr);
4292   ierr = MatSetSizes(*A,m,n,M,N);CHKERRQ(ierr);
4293   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
4294   if (size > 1) {
4295     ierr = MatSetType(*A,MATMPIAIJ);CHKERRQ(ierr);
4296     ierr = MatMPIAIJSetPreallocation(*A,d_nz,d_nnz,o_nz,o_nnz);CHKERRQ(ierr);
4297   } else {
4298     ierr = MatSetType(*A,MATSEQAIJ);CHKERRQ(ierr);
4299     ierr = MatSeqAIJSetPreallocation(*A,d_nz,d_nnz);CHKERRQ(ierr);
4300   }
4301   PetscFunctionReturn(0);
4302 }
4303 
4304 #undef __FUNCT__
4305 #define __FUNCT__ "MatMPIAIJGetSeqAIJ"
4306 PetscErrorCode  MatMPIAIJGetSeqAIJ(Mat A,Mat *Ad,Mat *Ao,const PetscInt *colmap[])
4307 {
4308   Mat_MPIAIJ *a = (Mat_MPIAIJ*)A->data;
4309 
4310   PetscFunctionBegin;
4311   *Ad     = a->A;
4312   *Ao     = a->B;
4313   *colmap = a->garray;
4314   PetscFunctionReturn(0);
4315 }
4316 
4317 #undef __FUNCT__
4318 #define __FUNCT__ "MatSetColoring_MPIAIJ"
4319 PetscErrorCode MatSetColoring_MPIAIJ(Mat A,ISColoring coloring)
4320 {
4321   PetscErrorCode ierr;
4322   PetscInt       i;
4323   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
4324 
4325   PetscFunctionBegin;
4326   if (coloring->ctype == IS_COLORING_GLOBAL) {
4327     ISColoringValue *allcolors,*colors;
4328     ISColoring      ocoloring;
4329 
4330     /* set coloring for diagonal portion */
4331     ierr = MatSetColoring_SeqAIJ(a->A,coloring);CHKERRQ(ierr);
4332 
4333     /* set coloring for off-diagonal portion */
4334     ierr = ISAllGatherColors(PetscObjectComm((PetscObject)A),coloring->n,coloring->colors,NULL,&allcolors);CHKERRQ(ierr);
4335     ierr = PetscMalloc((a->B->cmap->n+1)*sizeof(ISColoringValue),&colors);CHKERRQ(ierr);
4336     for (i=0; i<a->B->cmap->n; i++) {
4337       colors[i] = allcolors[a->garray[i]];
4338     }
4339     ierr = PetscFree(allcolors);CHKERRQ(ierr);
4340     ierr = ISColoringCreate(MPI_COMM_SELF,coloring->n,a->B->cmap->n,colors,&ocoloring);CHKERRQ(ierr);
4341     ierr = MatSetColoring_SeqAIJ(a->B,ocoloring);CHKERRQ(ierr);
4342     ierr = ISColoringDestroy(&ocoloring);CHKERRQ(ierr);
4343   } else if (coloring->ctype == IS_COLORING_GHOSTED) {
4344     ISColoringValue *colors;
4345     PetscInt        *larray;
4346     ISColoring      ocoloring;
4347 
4348     /* set coloring for diagonal portion */
4349     ierr = PetscMalloc((a->A->cmap->n+1)*sizeof(PetscInt),&larray);CHKERRQ(ierr);
4350     for (i=0; i<a->A->cmap->n; i++) {
4351       larray[i] = i + A->cmap->rstart;
4352     }
4353     ierr = ISGlobalToLocalMappingApply(A->cmap->mapping,IS_GTOLM_MASK,a->A->cmap->n,larray,NULL,larray);CHKERRQ(ierr);
4354     ierr = PetscMalloc((a->A->cmap->n+1)*sizeof(ISColoringValue),&colors);CHKERRQ(ierr);
4355     for (i=0; i<a->A->cmap->n; i++) {
4356       colors[i] = coloring->colors[larray[i]];
4357     }
4358     ierr = PetscFree(larray);CHKERRQ(ierr);
4359     ierr = ISColoringCreate(PETSC_COMM_SELF,coloring->n,a->A->cmap->n,colors,&ocoloring);CHKERRQ(ierr);
4360     ierr = MatSetColoring_SeqAIJ(a->A,ocoloring);CHKERRQ(ierr);
4361     ierr = ISColoringDestroy(&ocoloring);CHKERRQ(ierr);
4362 
4363     /* set coloring for off-diagonal portion */
4364     ierr = PetscMalloc((a->B->cmap->n+1)*sizeof(PetscInt),&larray);CHKERRQ(ierr);
4365     ierr = ISGlobalToLocalMappingApply(A->cmap->mapping,IS_GTOLM_MASK,a->B->cmap->n,a->garray,NULL,larray);CHKERRQ(ierr);
4366     ierr = PetscMalloc((a->B->cmap->n+1)*sizeof(ISColoringValue),&colors);CHKERRQ(ierr);
4367     for (i=0; i<a->B->cmap->n; i++) {
4368       colors[i] = coloring->colors[larray[i]];
4369     }
4370     ierr = PetscFree(larray);CHKERRQ(ierr);
4371     ierr = ISColoringCreate(MPI_COMM_SELF,coloring->n,a->B->cmap->n,colors,&ocoloring);CHKERRQ(ierr);
4372     ierr = MatSetColoring_SeqAIJ(a->B,ocoloring);CHKERRQ(ierr);
4373     ierr = ISColoringDestroy(&ocoloring);CHKERRQ(ierr);
4374   } else SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_SUP,"No support ISColoringType %d",(int)coloring->ctype);
4375   PetscFunctionReturn(0);
4376 }
4377 
4378 #undef __FUNCT__
4379 #define __FUNCT__ "MatSetValuesAdifor_MPIAIJ"
4380 PetscErrorCode MatSetValuesAdifor_MPIAIJ(Mat A,PetscInt nl,void *advalues)
4381 {
4382   Mat_MPIAIJ     *a = (Mat_MPIAIJ*)A->data;
4383   PetscErrorCode ierr;
4384 
4385   PetscFunctionBegin;
4386   ierr = MatSetValuesAdifor_SeqAIJ(a->A,nl,advalues);CHKERRQ(ierr);
4387   ierr = MatSetValuesAdifor_SeqAIJ(a->B,nl,advalues);CHKERRQ(ierr);
4388   PetscFunctionReturn(0);
4389 }
4390 
4391 #undef __FUNCT__
4392 #define __FUNCT__ "MatCreateMPIAIJConcatenateSeqAIJSymbolic"
4393 PetscErrorCode  MatCreateMPIAIJConcatenateSeqAIJSymbolic(MPI_Comm comm,Mat inmat,PetscInt n,Mat *outmat)
4394 {
4395   PetscErrorCode ierr;
4396   PetscInt       m,N,i,rstart,nnz,*dnz,*onz,sum,bs,cbs;
4397   PetscInt       *indx;
4398 
4399   PetscFunctionBegin;
4400   /* This routine will ONLY return MPIAIJ type matrix */
4401   ierr = MatGetSize(inmat,&m,&N);CHKERRQ(ierr);
4402   ierr = MatGetBlockSizes(inmat,&bs,&cbs);CHKERRQ(ierr);
4403   if (n == PETSC_DECIDE) {
4404     ierr = PetscSplitOwnership(comm,&n,&N);CHKERRQ(ierr);
4405   }
4406   /* Check sum(n) = N */
4407   ierr = MPI_Allreduce(&n,&sum,1,MPIU_INT,MPI_SUM,comm);CHKERRQ(ierr);
4408   if (sum != N) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_INCOMP,"Sum of local columns != global columns %d",N);
4409 
4410   ierr    = MPI_Scan(&m, &rstart,1,MPIU_INT,MPI_SUM,comm);CHKERRQ(ierr);
4411   rstart -= m;
4412 
4413   ierr = MatPreallocateInitialize(comm,m,n,dnz,onz);CHKERRQ(ierr);
4414   for (i=0; i<m; i++) {
4415     ierr = MatGetRow_SeqAIJ(inmat,i,&nnz,&indx,NULL);CHKERRQ(ierr);
4416     ierr = MatPreallocateSet(i+rstart,nnz,indx,dnz,onz);CHKERRQ(ierr);
4417     ierr = MatRestoreRow_SeqAIJ(inmat,i,&nnz,&indx,NULL);CHKERRQ(ierr);
4418   }
4419 
4420   ierr = MatCreate(comm,outmat);CHKERRQ(ierr);
4421   ierr = MatSetSizes(*outmat,m,n,PETSC_DETERMINE,PETSC_DETERMINE);CHKERRQ(ierr);
4422   ierr = MatSetBlockSizes(*outmat,bs,cbs);CHKERRQ(ierr);
4423   ierr = MatSetType(*outmat,MATMPIAIJ);CHKERRQ(ierr);
4424   ierr = MatMPIAIJSetPreallocation(*outmat,0,dnz,0,onz);CHKERRQ(ierr);
4425   ierr = MatPreallocateFinalize(dnz,onz);CHKERRQ(ierr);
4426   PetscFunctionReturn(0);
4427 }
4428 
4429 #undef __FUNCT__
4430 #define __FUNCT__ "MatCreateMPIAIJConcatenateSeqAIJNumeric"
4431 PetscErrorCode  MatCreateMPIAIJConcatenateSeqAIJNumeric(MPI_Comm comm,Mat inmat,PetscInt n,Mat outmat)
4432 {
4433   PetscErrorCode ierr;
4434   PetscInt       m,N,i,rstart,nnz,Ii;
4435   PetscInt       *indx;
4436   PetscScalar    *values;
4437 
4438   PetscFunctionBegin;
4439   ierr = MatGetSize(inmat,&m,&N);CHKERRQ(ierr);
4440   ierr = MatGetOwnershipRange(outmat,&rstart,NULL);CHKERRQ(ierr);
4441   for (i=0; i<m; i++) {
4442     ierr = MatGetRow_SeqAIJ(inmat,i,&nnz,&indx,&values);CHKERRQ(ierr);
4443     Ii   = i + rstart;
4444     ierr = MatSetValues_MPIAIJ(outmat,1,&Ii,nnz,indx,values,INSERT_VALUES);CHKERRQ(ierr);
4445     ierr = MatRestoreRow_SeqAIJ(inmat,i,&nnz,&indx,&values);CHKERRQ(ierr);
4446   }
4447   ierr = MatAssemblyBegin(outmat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
4448   ierr = MatAssemblyEnd(outmat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
4449   PetscFunctionReturn(0);
4450 }
4451 
4452 #undef __FUNCT__
4453 #define __FUNCT__ "MatCreateMPIAIJConcatenateSeqAIJ"
4454 /*@
4455       MatCreateMPIAIJConcatenateSeqAIJ - Creates a single large PETSc matrix by concatenating sequential
4456                  matrices from each processor
4457 
4458     Collective on MPI_Comm
4459 
4460    Input Parameters:
4461 +    comm - the communicators the parallel matrix will live on
4462 .    inmat - the input sequential matrices
4463 .    n - number of local columns (or PETSC_DECIDE)
4464 -    scall - either MAT_INITIAL_MATRIX or MAT_REUSE_MATRIX
4465 
4466    Output Parameter:
4467 .    outmat - the parallel matrix generated
4468 
4469     Level: advanced
4470 
4471    Notes: The number of columns of the matrix in EACH processor MUST be the same.
4472 
4473 @*/
4474 PetscErrorCode  MatCreateMPIAIJConcatenateSeqAIJ(MPI_Comm comm,Mat inmat,PetscInt n,MatReuse scall,Mat *outmat)
4475 {
4476   PetscErrorCode ierr;
4477 
4478   PetscFunctionBegin;
4479   ierr = PetscLogEventBegin(MAT_Merge,inmat,0,0,0);CHKERRQ(ierr);
4480   if (scall == MAT_INITIAL_MATRIX) {
4481     ierr = MatCreateMPIAIJConcatenateSeqAIJSymbolic(comm,inmat,n,outmat);CHKERRQ(ierr);
4482   }
4483   ierr = MatCreateMPIAIJConcatenateSeqAIJNumeric(comm,inmat,n,*outmat);CHKERRQ(ierr);
4484   ierr = PetscLogEventEnd(MAT_Merge,inmat,0,0,0);CHKERRQ(ierr);
4485   PetscFunctionReturn(0);
4486 }
4487 
4488 #undef __FUNCT__
4489 #define __FUNCT__ "MatFileSplit"
4490 PetscErrorCode MatFileSplit(Mat A,char *outfile)
4491 {
4492   PetscErrorCode    ierr;
4493   PetscMPIInt       rank;
4494   PetscInt          m,N,i,rstart,nnz;
4495   size_t            len;
4496   const PetscInt    *indx;
4497   PetscViewer       out;
4498   char              *name;
4499   Mat               B;
4500   const PetscScalar *values;
4501 
4502   PetscFunctionBegin;
4503   ierr = MatGetLocalSize(A,&m,0);CHKERRQ(ierr);
4504   ierr = MatGetSize(A,0,&N);CHKERRQ(ierr);
4505   /* Should this be the type of the diagonal block of A? */
4506   ierr = MatCreate(PETSC_COMM_SELF,&B);CHKERRQ(ierr);
4507   ierr = MatSetSizes(B,m,N,m,N);CHKERRQ(ierr);
4508   ierr = MatSetBlockSizes(B,A->rmap->bs,A->cmap->bs);CHKERRQ(ierr);
4509   ierr = MatSetType(B,MATSEQAIJ);CHKERRQ(ierr);
4510   ierr = MatSeqAIJSetPreallocation(B,0,NULL);CHKERRQ(ierr);
4511   ierr = MatGetOwnershipRange(A,&rstart,0);CHKERRQ(ierr);
4512   for (i=0; i<m; i++) {
4513     ierr = MatGetRow(A,i+rstart,&nnz,&indx,&values);CHKERRQ(ierr);
4514     ierr = MatSetValues(B,1,&i,nnz,indx,values,INSERT_VALUES);CHKERRQ(ierr);
4515     ierr = MatRestoreRow(A,i+rstart,&nnz,&indx,&values);CHKERRQ(ierr);
4516   }
4517   ierr = MatAssemblyBegin(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
4518   ierr = MatAssemblyEnd(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
4519 
4520   ierr = MPI_Comm_rank(PetscObjectComm((PetscObject)A),&rank);CHKERRQ(ierr);
4521   ierr = PetscStrlen(outfile,&len);CHKERRQ(ierr);
4522   ierr = PetscMalloc((len+5)*sizeof(char),&name);CHKERRQ(ierr);
4523   sprintf(name,"%s.%d",outfile,rank);
4524   ierr = PetscViewerBinaryOpen(PETSC_COMM_SELF,name,FILE_MODE_APPEND,&out);CHKERRQ(ierr);
4525   ierr = PetscFree(name);CHKERRQ(ierr);
4526   ierr = MatView(B,out);CHKERRQ(ierr);
4527   ierr = PetscViewerDestroy(&out);CHKERRQ(ierr);
4528   ierr = MatDestroy(&B);CHKERRQ(ierr);
4529   PetscFunctionReturn(0);
4530 }
4531 
4532 extern PetscErrorCode MatDestroy_MPIAIJ(Mat);
4533 #undef __FUNCT__
4534 #define __FUNCT__ "MatDestroy_MPIAIJ_SeqsToMPI"
4535 PetscErrorCode  MatDestroy_MPIAIJ_SeqsToMPI(Mat A)
4536 {
4537   PetscErrorCode      ierr;
4538   Mat_Merge_SeqsToMPI *merge;
4539   PetscContainer      container;
4540 
4541   PetscFunctionBegin;
4542   ierr = PetscObjectQuery((PetscObject)A,"MatMergeSeqsToMPI",(PetscObject*)&container);CHKERRQ(ierr);
4543   if (container) {
4544     ierr = PetscContainerGetPointer(container,(void**)&merge);CHKERRQ(ierr);
4545     ierr = PetscFree(merge->id_r);CHKERRQ(ierr);
4546     ierr = PetscFree(merge->len_s);CHKERRQ(ierr);
4547     ierr = PetscFree(merge->len_r);CHKERRQ(ierr);
4548     ierr = PetscFree(merge->bi);CHKERRQ(ierr);
4549     ierr = PetscFree(merge->bj);CHKERRQ(ierr);
4550     ierr = PetscFree(merge->buf_ri[0]);CHKERRQ(ierr);
4551     ierr = PetscFree(merge->buf_ri);CHKERRQ(ierr);
4552     ierr = PetscFree(merge->buf_rj[0]);CHKERRQ(ierr);
4553     ierr = PetscFree(merge->buf_rj);CHKERRQ(ierr);
4554     ierr = PetscFree(merge->coi);CHKERRQ(ierr);
4555     ierr = PetscFree(merge->coj);CHKERRQ(ierr);
4556     ierr = PetscFree(merge->owners_co);CHKERRQ(ierr);
4557     ierr = PetscLayoutDestroy(&merge->rowmap);CHKERRQ(ierr);
4558     ierr = PetscFree(merge);CHKERRQ(ierr);
4559     ierr = PetscObjectCompose((PetscObject)A,"MatMergeSeqsToMPI",0);CHKERRQ(ierr);
4560   }
4561   ierr = MatDestroy_MPIAIJ(A);CHKERRQ(ierr);
4562   PetscFunctionReturn(0);
4563 }
4564 
4565 #include <../src/mat/utils/freespace.h>
4566 #include <petscbt.h>
4567 
4568 #undef __FUNCT__
4569 #define __FUNCT__ "MatCreateMPIAIJSumSeqAIJNumeric"
4570 PetscErrorCode  MatCreateMPIAIJSumSeqAIJNumeric(Mat seqmat,Mat mpimat)
4571 {
4572   PetscErrorCode      ierr;
4573   MPI_Comm            comm;
4574   Mat_SeqAIJ          *a  =(Mat_SeqAIJ*)seqmat->data;
4575   PetscMPIInt         size,rank,taga,*len_s;
4576   PetscInt            N=mpimat->cmap->N,i,j,*owners,*ai=a->i,*aj;
4577   PetscInt            proc,m;
4578   PetscInt            **buf_ri,**buf_rj;
4579   PetscInt            k,anzi,*bj_i,*bi,*bj,arow,bnzi,nextaj;
4580   PetscInt            nrows,**buf_ri_k,**nextrow,**nextai;
4581   MPI_Request         *s_waits,*r_waits;
4582   MPI_Status          *status;
4583   MatScalar           *aa=a->a;
4584   MatScalar           **abuf_r,*ba_i;
4585   Mat_Merge_SeqsToMPI *merge;
4586   PetscContainer      container;
4587 
4588   PetscFunctionBegin;
4589   ierr = PetscObjectGetComm((PetscObject)mpimat,&comm);CHKERRQ(ierr);
4590   ierr = PetscLogEventBegin(MAT_Seqstompinum,seqmat,0,0,0);CHKERRQ(ierr);
4591 
4592   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
4593   ierr = MPI_Comm_rank(comm,&rank);CHKERRQ(ierr);
4594 
4595   ierr = PetscObjectQuery((PetscObject)mpimat,"MatMergeSeqsToMPI",(PetscObject*)&container);CHKERRQ(ierr);
4596   ierr = PetscContainerGetPointer(container,(void**)&merge);CHKERRQ(ierr);
4597 
4598   bi     = merge->bi;
4599   bj     = merge->bj;
4600   buf_ri = merge->buf_ri;
4601   buf_rj = merge->buf_rj;
4602 
4603   ierr   = PetscMalloc(size*sizeof(MPI_Status),&status);CHKERRQ(ierr);
4604   owners = merge->rowmap->range;
4605   len_s  = merge->len_s;
4606 
4607   /* send and recv matrix values */
4608   /*-----------------------------*/
4609   ierr = PetscObjectGetNewTag((PetscObject)mpimat,&taga);CHKERRQ(ierr);
4610   ierr = PetscPostIrecvScalar(comm,taga,merge->nrecv,merge->id_r,merge->len_r,&abuf_r,&r_waits);CHKERRQ(ierr);
4611 
4612   ierr = PetscMalloc((merge->nsend+1)*sizeof(MPI_Request),&s_waits);CHKERRQ(ierr);
4613   for (proc=0,k=0; proc<size; proc++) {
4614     if (!len_s[proc]) continue;
4615     i    = owners[proc];
4616     ierr = MPI_Isend(aa+ai[i],len_s[proc],MPIU_MATSCALAR,proc,taga,comm,s_waits+k);CHKERRQ(ierr);
4617     k++;
4618   }
4619 
4620   if (merge->nrecv) {ierr = MPI_Waitall(merge->nrecv,r_waits,status);CHKERRQ(ierr);}
4621   if (merge->nsend) {ierr = MPI_Waitall(merge->nsend,s_waits,status);CHKERRQ(ierr);}
4622   ierr = PetscFree(status);CHKERRQ(ierr);
4623 
4624   ierr = PetscFree(s_waits);CHKERRQ(ierr);
4625   ierr = PetscFree(r_waits);CHKERRQ(ierr);
4626 
4627   /* insert mat values of mpimat */
4628   /*----------------------------*/
4629   ierr = PetscMalloc(N*sizeof(PetscScalar),&ba_i);CHKERRQ(ierr);
4630   ierr = PetscMalloc3(merge->nrecv,PetscInt*,&buf_ri_k,merge->nrecv,PetscInt*,&nextrow,merge->nrecv,PetscInt*,&nextai);CHKERRQ(ierr);
4631 
4632   for (k=0; k<merge->nrecv; k++) {
4633     buf_ri_k[k] = buf_ri[k]; /* beginning of k-th recved i-structure */
4634     nrows       = *(buf_ri_k[k]);
4635     nextrow[k]  = buf_ri_k[k]+1;  /* next row number of k-th recved i-structure */
4636     nextai[k]   = buf_ri_k[k] + (nrows + 1); /* poins to the next i-structure of k-th recved i-structure  */
4637   }
4638 
4639   /* set values of ba */
4640   m = merge->rowmap->n;
4641   for (i=0; i<m; i++) {
4642     arow = owners[rank] + i;
4643     bj_i = bj+bi[i];  /* col indices of the i-th row of mpimat */
4644     bnzi = bi[i+1] - bi[i];
4645     ierr = PetscMemzero(ba_i,bnzi*sizeof(PetscScalar));CHKERRQ(ierr);
4646 
4647     /* add local non-zero vals of this proc's seqmat into ba */
4648     anzi   = ai[arow+1] - ai[arow];
4649     aj     = a->j + ai[arow];
4650     aa     = a->a + ai[arow];
4651     nextaj = 0;
4652     for (j=0; nextaj<anzi; j++) {
4653       if (*(bj_i + j) == aj[nextaj]) { /* bcol == acol */
4654         ba_i[j] += aa[nextaj++];
4655       }
4656     }
4657 
4658     /* add received vals into ba */
4659     for (k=0; k<merge->nrecv; k++) { /* k-th received message */
4660       /* i-th row */
4661       if (i == *nextrow[k]) {
4662         anzi   = *(nextai[k]+1) - *nextai[k];
4663         aj     = buf_rj[k] + *(nextai[k]);
4664         aa     = abuf_r[k] + *(nextai[k]);
4665         nextaj = 0;
4666         for (j=0; nextaj<anzi; j++) {
4667           if (*(bj_i + j) == aj[nextaj]) { /* bcol == acol */
4668             ba_i[j] += aa[nextaj++];
4669           }
4670         }
4671         nextrow[k]++; nextai[k]++;
4672       }
4673     }
4674     ierr = MatSetValues(mpimat,1,&arow,bnzi,bj_i,ba_i,INSERT_VALUES);CHKERRQ(ierr);
4675   }
4676   ierr = MatAssemblyBegin(mpimat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
4677   ierr = MatAssemblyEnd(mpimat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
4678 
4679   ierr = PetscFree(abuf_r[0]);CHKERRQ(ierr);
4680   ierr = PetscFree(abuf_r);CHKERRQ(ierr);
4681   ierr = PetscFree(ba_i);CHKERRQ(ierr);
4682   ierr = PetscFree3(buf_ri_k,nextrow,nextai);CHKERRQ(ierr);
4683   ierr = PetscLogEventEnd(MAT_Seqstompinum,seqmat,0,0,0);CHKERRQ(ierr);
4684   PetscFunctionReturn(0);
4685 }
4686 
4687 extern PetscErrorCode  MatDestroy_MPIAIJ_SeqsToMPI(Mat);
4688 
4689 #undef __FUNCT__
4690 #define __FUNCT__ "MatCreateMPIAIJSumSeqAIJSymbolic"
4691 PetscErrorCode  MatCreateMPIAIJSumSeqAIJSymbolic(MPI_Comm comm,Mat seqmat,PetscInt m,PetscInt n,Mat *mpimat)
4692 {
4693   PetscErrorCode      ierr;
4694   Mat                 B_mpi;
4695   Mat_SeqAIJ          *a=(Mat_SeqAIJ*)seqmat->data;
4696   PetscMPIInt         size,rank,tagi,tagj,*len_s,*len_si,*len_ri;
4697   PetscInt            **buf_rj,**buf_ri,**buf_ri_k;
4698   PetscInt            M=seqmat->rmap->n,N=seqmat->cmap->n,i,*owners,*ai=a->i,*aj=a->j;
4699   PetscInt            len,proc,*dnz,*onz,bs,cbs;
4700   PetscInt            k,anzi,*bi,*bj,*lnk,nlnk,arow,bnzi,nspacedouble=0;
4701   PetscInt            nrows,*buf_s,*buf_si,*buf_si_i,**nextrow,**nextai;
4702   MPI_Request         *si_waits,*sj_waits,*ri_waits,*rj_waits;
4703   MPI_Status          *status;
4704   PetscFreeSpaceList  free_space=NULL,current_space=NULL;
4705   PetscBT             lnkbt;
4706   Mat_Merge_SeqsToMPI *merge;
4707   PetscContainer      container;
4708 
4709   PetscFunctionBegin;
4710   ierr = PetscLogEventBegin(MAT_Seqstompisym,seqmat,0,0,0);CHKERRQ(ierr);
4711 
4712   /* make sure it is a PETSc comm */
4713   ierr = PetscCommDuplicate(comm,&comm,NULL);CHKERRQ(ierr);
4714   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
4715   ierr = MPI_Comm_rank(comm,&rank);CHKERRQ(ierr);
4716 
4717   ierr = PetscNew(Mat_Merge_SeqsToMPI,&merge);CHKERRQ(ierr);
4718   ierr = PetscMalloc(size*sizeof(MPI_Status),&status);CHKERRQ(ierr);
4719 
4720   /* determine row ownership */
4721   /*---------------------------------------------------------*/
4722   ierr = PetscLayoutCreate(comm,&merge->rowmap);CHKERRQ(ierr);
4723   ierr = PetscLayoutSetLocalSize(merge->rowmap,m);CHKERRQ(ierr);
4724   ierr = PetscLayoutSetSize(merge->rowmap,M);CHKERRQ(ierr);
4725   ierr = PetscLayoutSetBlockSize(merge->rowmap,1);CHKERRQ(ierr);
4726   ierr = PetscLayoutSetUp(merge->rowmap);CHKERRQ(ierr);
4727   ierr = PetscMalloc(size*sizeof(PetscMPIInt),&len_si);CHKERRQ(ierr);
4728   ierr = PetscMalloc(size*sizeof(PetscMPIInt),&merge->len_s);CHKERRQ(ierr);
4729 
4730   m      = merge->rowmap->n;
4731   owners = merge->rowmap->range;
4732 
4733   /* determine the number of messages to send, their lengths */
4734   /*---------------------------------------------------------*/
4735   len_s = merge->len_s;
4736 
4737   len          = 0; /* length of buf_si[] */
4738   merge->nsend = 0;
4739   for (proc=0; proc<size; proc++) {
4740     len_si[proc] = 0;
4741     if (proc == rank) {
4742       len_s[proc] = 0;
4743     } else {
4744       len_si[proc] = owners[proc+1] - owners[proc] + 1;
4745       len_s[proc]  = ai[owners[proc+1]] - ai[owners[proc]]; /* num of rows to be sent to [proc] */
4746     }
4747     if (len_s[proc]) {
4748       merge->nsend++;
4749       nrows = 0;
4750       for (i=owners[proc]; i<owners[proc+1]; i++) {
4751         if (ai[i+1] > ai[i]) nrows++;
4752       }
4753       len_si[proc] = 2*(nrows+1);
4754       len         += len_si[proc];
4755     }
4756   }
4757 
4758   /* determine the number and length of messages to receive for ij-structure */
4759   /*-------------------------------------------------------------------------*/
4760   ierr = PetscGatherNumberOfMessages(comm,NULL,len_s,&merge->nrecv);CHKERRQ(ierr);
4761   ierr = PetscGatherMessageLengths2(comm,merge->nsend,merge->nrecv,len_s,len_si,&merge->id_r,&merge->len_r,&len_ri);CHKERRQ(ierr);
4762 
4763   /* post the Irecv of j-structure */
4764   /*-------------------------------*/
4765   ierr = PetscCommGetNewTag(comm,&tagj);CHKERRQ(ierr);
4766   ierr = PetscPostIrecvInt(comm,tagj,merge->nrecv,merge->id_r,merge->len_r,&buf_rj,&rj_waits);CHKERRQ(ierr);
4767 
4768   /* post the Isend of j-structure */
4769   /*--------------------------------*/
4770   ierr = PetscMalloc2(merge->nsend,MPI_Request,&si_waits,merge->nsend,MPI_Request,&sj_waits);CHKERRQ(ierr);
4771 
4772   for (proc=0, k=0; proc<size; proc++) {
4773     if (!len_s[proc]) continue;
4774     i    = owners[proc];
4775     ierr = MPI_Isend(aj+ai[i],len_s[proc],MPIU_INT,proc,tagj,comm,sj_waits+k);CHKERRQ(ierr);
4776     k++;
4777   }
4778 
4779   /* receives and sends of j-structure are complete */
4780   /*------------------------------------------------*/
4781   if (merge->nrecv) {ierr = MPI_Waitall(merge->nrecv,rj_waits,status);CHKERRQ(ierr);}
4782   if (merge->nsend) {ierr = MPI_Waitall(merge->nsend,sj_waits,status);CHKERRQ(ierr);}
4783 
4784   /* send and recv i-structure */
4785   /*---------------------------*/
4786   ierr = PetscCommGetNewTag(comm,&tagi);CHKERRQ(ierr);
4787   ierr = PetscPostIrecvInt(comm,tagi,merge->nrecv,merge->id_r,len_ri,&buf_ri,&ri_waits);CHKERRQ(ierr);
4788 
4789   ierr   = PetscMalloc((len+1)*sizeof(PetscInt),&buf_s);CHKERRQ(ierr);
4790   buf_si = buf_s;  /* points to the beginning of k-th msg to be sent */
4791   for (proc=0,k=0; proc<size; proc++) {
4792     if (!len_s[proc]) continue;
4793     /* form outgoing message for i-structure:
4794          buf_si[0]:                 nrows to be sent
4795                [1:nrows]:           row index (global)
4796                [nrows+1:2*nrows+1]: i-structure index
4797     */
4798     /*-------------------------------------------*/
4799     nrows       = len_si[proc]/2 - 1;
4800     buf_si_i    = buf_si + nrows+1;
4801     buf_si[0]   = nrows;
4802     buf_si_i[0] = 0;
4803     nrows       = 0;
4804     for (i=owners[proc]; i<owners[proc+1]; i++) {
4805       anzi = ai[i+1] - ai[i];
4806       if (anzi) {
4807         buf_si_i[nrows+1] = buf_si_i[nrows] + anzi; /* i-structure */
4808         buf_si[nrows+1]   = i-owners[proc]; /* local row index */
4809         nrows++;
4810       }
4811     }
4812     ierr = MPI_Isend(buf_si,len_si[proc],MPIU_INT,proc,tagi,comm,si_waits+k);CHKERRQ(ierr);
4813     k++;
4814     buf_si += len_si[proc];
4815   }
4816 
4817   if (merge->nrecv) {ierr = MPI_Waitall(merge->nrecv,ri_waits,status);CHKERRQ(ierr);}
4818   if (merge->nsend) {ierr = MPI_Waitall(merge->nsend,si_waits,status);CHKERRQ(ierr);}
4819 
4820   ierr = PetscInfo2(seqmat,"nsend: %D, nrecv: %D\n",merge->nsend,merge->nrecv);CHKERRQ(ierr);
4821   for (i=0; i<merge->nrecv; i++) {
4822     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);
4823   }
4824 
4825   ierr = PetscFree(len_si);CHKERRQ(ierr);
4826   ierr = PetscFree(len_ri);CHKERRQ(ierr);
4827   ierr = PetscFree(rj_waits);CHKERRQ(ierr);
4828   ierr = PetscFree2(si_waits,sj_waits);CHKERRQ(ierr);
4829   ierr = PetscFree(ri_waits);CHKERRQ(ierr);
4830   ierr = PetscFree(buf_s);CHKERRQ(ierr);
4831   ierr = PetscFree(status);CHKERRQ(ierr);
4832 
4833   /* compute a local seq matrix in each processor */
4834   /*----------------------------------------------*/
4835   /* allocate bi array and free space for accumulating nonzero column info */
4836   ierr  = PetscMalloc((m+1)*sizeof(PetscInt),&bi);CHKERRQ(ierr);
4837   bi[0] = 0;
4838 
4839   /* create and initialize a linked list */
4840   nlnk = N+1;
4841   ierr = PetscLLCreate(N,N,nlnk,lnk,lnkbt);CHKERRQ(ierr);
4842 
4843   /* initial FreeSpace size is 2*(num of local nnz(seqmat)) */
4844   len  = ai[owners[rank+1]] - ai[owners[rank]];
4845   ierr = PetscFreeSpaceGet((PetscInt)(2*len+1),&free_space);CHKERRQ(ierr);
4846 
4847   current_space = free_space;
4848 
4849   /* determine symbolic info for each local row */
4850   ierr = PetscMalloc3(merge->nrecv,PetscInt*,&buf_ri_k,merge->nrecv,PetscInt*,&nextrow,merge->nrecv,PetscInt*,&nextai);CHKERRQ(ierr);
4851 
4852   for (k=0; k<merge->nrecv; k++) {
4853     buf_ri_k[k] = buf_ri[k]; /* beginning of k-th recved i-structure */
4854     nrows       = *buf_ri_k[k];
4855     nextrow[k]  = buf_ri_k[k] + 1;  /* next row number of k-th recved i-structure */
4856     nextai[k]   = buf_ri_k[k] + (nrows + 1); /* poins to the next i-structure of k-th recved i-structure  */
4857   }
4858 
4859   ierr = MatPreallocateInitialize(comm,m,n,dnz,onz);CHKERRQ(ierr);
4860   len  = 0;
4861   for (i=0; i<m; i++) {
4862     bnzi = 0;
4863     /* add local non-zero cols of this proc's seqmat into lnk */
4864     arow  = owners[rank] + i;
4865     anzi  = ai[arow+1] - ai[arow];
4866     aj    = a->j + ai[arow];
4867     ierr  = PetscLLAddSorted(anzi,aj,N,nlnk,lnk,lnkbt);CHKERRQ(ierr);
4868     bnzi += nlnk;
4869     /* add received col data into lnk */
4870     for (k=0; k<merge->nrecv; k++) { /* k-th received message */
4871       if (i == *nextrow[k]) { /* i-th row */
4872         anzi  = *(nextai[k]+1) - *nextai[k];
4873         aj    = buf_rj[k] + *nextai[k];
4874         ierr  = PetscLLAddSorted(anzi,aj,N,nlnk,lnk,lnkbt);CHKERRQ(ierr);
4875         bnzi += nlnk;
4876         nextrow[k]++; nextai[k]++;
4877       }
4878     }
4879     if (len < bnzi) len = bnzi;  /* =max(bnzi) */
4880 
4881     /* if free space is not available, make more free space */
4882     if (current_space->local_remaining<bnzi) {
4883       ierr = PetscFreeSpaceGet(bnzi+current_space->total_array_size,&current_space);CHKERRQ(ierr);
4884       nspacedouble++;
4885     }
4886     /* copy data into free space, then initialize lnk */
4887     ierr = PetscLLClean(N,N,bnzi,lnk,current_space->array,lnkbt);CHKERRQ(ierr);
4888     ierr = MatPreallocateSet(i+owners[rank],bnzi,current_space->array,dnz,onz);CHKERRQ(ierr);
4889 
4890     current_space->array           += bnzi;
4891     current_space->local_used      += bnzi;
4892     current_space->local_remaining -= bnzi;
4893 
4894     bi[i+1] = bi[i] + bnzi;
4895   }
4896 
4897   ierr = PetscFree3(buf_ri_k,nextrow,nextai);CHKERRQ(ierr);
4898 
4899   ierr = PetscMalloc((bi[m]+1)*sizeof(PetscInt),&bj);CHKERRQ(ierr);
4900   ierr = PetscFreeSpaceContiguous(&free_space,bj);CHKERRQ(ierr);
4901   ierr = PetscLLDestroy(lnk,lnkbt);CHKERRQ(ierr);
4902 
4903   /* create symbolic parallel matrix B_mpi */
4904   /*---------------------------------------*/
4905   ierr = MatGetBlockSizes(seqmat,&bs,&cbs);CHKERRQ(ierr);
4906   ierr = MatCreate(comm,&B_mpi);CHKERRQ(ierr);
4907   if (n==PETSC_DECIDE) {
4908     ierr = MatSetSizes(B_mpi,m,n,PETSC_DETERMINE,N);CHKERRQ(ierr);
4909   } else {
4910     ierr = MatSetSizes(B_mpi,m,n,PETSC_DETERMINE,PETSC_DETERMINE);CHKERRQ(ierr);
4911   }
4912   ierr = MatSetBlockSizes(B_mpi,bs,cbs);CHKERRQ(ierr);
4913   ierr = MatSetType(B_mpi,MATMPIAIJ);CHKERRQ(ierr);
4914   ierr = MatMPIAIJSetPreallocation(B_mpi,0,dnz,0,onz);CHKERRQ(ierr);
4915   ierr = MatPreallocateFinalize(dnz,onz);CHKERRQ(ierr);
4916   ierr = MatSetOption(B_mpi,MAT_NEW_NONZERO_ALLOCATION_ERR,PETSC_FALSE);CHKERRQ(ierr);
4917 
4918   /* B_mpi is not ready for use - assembly will be done by MatCreateMPIAIJSumSeqAIJNumeric() */
4919   B_mpi->assembled    = PETSC_FALSE;
4920   B_mpi->ops->destroy = MatDestroy_MPIAIJ_SeqsToMPI;
4921   merge->bi           = bi;
4922   merge->bj           = bj;
4923   merge->buf_ri       = buf_ri;
4924   merge->buf_rj       = buf_rj;
4925   merge->coi          = NULL;
4926   merge->coj          = NULL;
4927   merge->owners_co    = NULL;
4928 
4929   ierr = PetscCommDestroy(&comm);CHKERRQ(ierr);
4930 
4931   /* attach the supporting struct to B_mpi for reuse */
4932   ierr    = PetscContainerCreate(PETSC_COMM_SELF,&container);CHKERRQ(ierr);
4933   ierr    = PetscContainerSetPointer(container,merge);CHKERRQ(ierr);
4934   ierr    = PetscObjectCompose((PetscObject)B_mpi,"MatMergeSeqsToMPI",(PetscObject)container);CHKERRQ(ierr);
4935   ierr    = PetscContainerDestroy(&container);CHKERRQ(ierr);
4936   *mpimat = B_mpi;
4937 
4938   ierr = PetscLogEventEnd(MAT_Seqstompisym,seqmat,0,0,0);CHKERRQ(ierr);
4939   PetscFunctionReturn(0);
4940 }
4941 
4942 #undef __FUNCT__
4943 #define __FUNCT__ "MatCreateMPIAIJSumSeqAIJ"
4944 /*@C
4945       MatCreateMPIAIJSumSeqAIJ - Creates a MPIAIJ matrix by adding sequential
4946                  matrices from each processor
4947 
4948     Collective on MPI_Comm
4949 
4950    Input Parameters:
4951 +    comm - the communicators the parallel matrix will live on
4952 .    seqmat - the input sequential matrices
4953 .    m - number of local rows (or PETSC_DECIDE)
4954 .    n - number of local columns (or PETSC_DECIDE)
4955 -    scall - either MAT_INITIAL_MATRIX or MAT_REUSE_MATRIX
4956 
4957    Output Parameter:
4958 .    mpimat - the parallel matrix generated
4959 
4960     Level: advanced
4961 
4962    Notes:
4963      The dimensions of the sequential matrix in each processor MUST be the same.
4964      The input seqmat is included into the container "Mat_Merge_SeqsToMPI", and will be
4965      destroyed when mpimat is destroyed. Call PetscObjectQuery() to access seqmat.
4966 @*/
4967 PetscErrorCode  MatCreateMPIAIJSumSeqAIJ(MPI_Comm comm,Mat seqmat,PetscInt m,PetscInt n,MatReuse scall,Mat *mpimat)
4968 {
4969   PetscErrorCode ierr;
4970   PetscMPIInt    size;
4971 
4972   PetscFunctionBegin;
4973   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
4974   if (size == 1) {
4975     ierr = PetscLogEventBegin(MAT_Seqstompi,seqmat,0,0,0);CHKERRQ(ierr);
4976     if (scall == MAT_INITIAL_MATRIX) {
4977       ierr = MatDuplicate(seqmat,MAT_COPY_VALUES,mpimat);CHKERRQ(ierr);
4978     } else {
4979       ierr = MatCopy(seqmat,*mpimat,SAME_NONZERO_PATTERN);CHKERRQ(ierr);
4980     }
4981     ierr = PetscLogEventEnd(MAT_Seqstompi,seqmat,0,0,0);CHKERRQ(ierr);
4982     PetscFunctionReturn(0);
4983   }
4984   ierr = PetscLogEventBegin(MAT_Seqstompi,seqmat,0,0,0);CHKERRQ(ierr);
4985   if (scall == MAT_INITIAL_MATRIX) {
4986     ierr = MatCreateMPIAIJSumSeqAIJSymbolic(comm,seqmat,m,n,mpimat);CHKERRQ(ierr);
4987   }
4988   ierr = MatCreateMPIAIJSumSeqAIJNumeric(seqmat,*mpimat);CHKERRQ(ierr);
4989   ierr = PetscLogEventEnd(MAT_Seqstompi,seqmat,0,0,0);CHKERRQ(ierr);
4990   PetscFunctionReturn(0);
4991 }
4992 
4993 #undef __FUNCT__
4994 #define __FUNCT__ "MatMPIAIJGetLocalMat"
4995 /*@
4996      MatMPIAIJGetLocalMat - Creates a SeqAIJ from a MPIAIJ matrix by taking all its local rows and putting them into a sequential vector with
4997           mlocal rows and n columns. Where mlocal is the row count obtained with MatGetLocalSize() and n is the global column count obtained
4998           with MatGetSize()
4999 
5000     Not Collective
5001 
5002    Input Parameters:
5003 +    A - the matrix
5004 .    scall - either MAT_INITIAL_MATRIX or MAT_REUSE_MATRIX
5005 
5006    Output Parameter:
5007 .    A_loc - the local sequential matrix generated
5008 
5009     Level: developer
5010 
5011 .seealso: MatGetOwnerShipRange(), MatMPIAIJGetLocalMatCondensed()
5012 
5013 @*/
5014 PetscErrorCode  MatMPIAIJGetLocalMat(Mat A,MatReuse scall,Mat *A_loc)
5015 {
5016   PetscErrorCode ierr;
5017   Mat_MPIAIJ     *mpimat=(Mat_MPIAIJ*)A->data;
5018   Mat_SeqAIJ     *mat,*a=(Mat_SeqAIJ*)(mpimat->A)->data,*b=(Mat_SeqAIJ*)(mpimat->B)->data;
5019   PetscInt       *ai=a->i,*aj=a->j,*bi=b->i,*bj=b->j,*cmap=mpimat->garray;
5020   MatScalar      *aa=a->a,*ba=b->a,*cam;
5021   PetscScalar    *ca;
5022   PetscInt       am=A->rmap->n,i,j,k,cstart=A->cmap->rstart;
5023   PetscInt       *ci,*cj,col,ncols_d,ncols_o,jo;
5024   PetscBool      match;
5025 
5026   PetscFunctionBegin;
5027   ierr = PetscObjectTypeCompare((PetscObject)A,MATMPIAIJ,&match);CHKERRQ(ierr);
5028   if (!match) SETERRQ(PetscObjectComm((PetscObject)A), PETSC_ERR_SUP,"Requires MPIAIJ matrix as input");
5029   ierr = PetscLogEventBegin(MAT_Getlocalmat,A,0,0,0);CHKERRQ(ierr);
5030   if (scall == MAT_INITIAL_MATRIX) {
5031     ierr  = PetscMalloc((1+am)*sizeof(PetscInt),&ci);CHKERRQ(ierr);
5032     ci[0] = 0;
5033     for (i=0; i<am; i++) {
5034       ci[i+1] = ci[i] + (ai[i+1] - ai[i]) + (bi[i+1] - bi[i]);
5035     }
5036     ierr = PetscMalloc((1+ci[am])*sizeof(PetscInt),&cj);CHKERRQ(ierr);
5037     ierr = PetscMalloc((1+ci[am])*sizeof(PetscScalar),&ca);CHKERRQ(ierr);
5038     k    = 0;
5039     for (i=0; i<am; i++) {
5040       ncols_o = bi[i+1] - bi[i];
5041       ncols_d = ai[i+1] - ai[i];
5042       /* off-diagonal portion of A */
5043       for (jo=0; jo<ncols_o; jo++) {
5044         col = cmap[*bj];
5045         if (col >= cstart) break;
5046         cj[k]   = col; bj++;
5047         ca[k++] = *ba++;
5048       }
5049       /* diagonal portion of A */
5050       for (j=0; j<ncols_d; j++) {
5051         cj[k]   = cstart + *aj++;
5052         ca[k++] = *aa++;
5053       }
5054       /* off-diagonal portion of A */
5055       for (j=jo; j<ncols_o; j++) {
5056         cj[k]   = cmap[*bj++];
5057         ca[k++] = *ba++;
5058       }
5059     }
5060     /* put together the new matrix */
5061     ierr = MatCreateSeqAIJWithArrays(PETSC_COMM_SELF,am,A->cmap->N,ci,cj,ca,A_loc);CHKERRQ(ierr);
5062     /* MatCreateSeqAIJWithArrays flags matrix so PETSc doesn't free the user's arrays. */
5063     /* Since these are PETSc arrays, change flags to free them as necessary. */
5064     mat          = (Mat_SeqAIJ*)(*A_loc)->data;
5065     mat->free_a  = PETSC_TRUE;
5066     mat->free_ij = PETSC_TRUE;
5067     mat->nonew   = 0;
5068   } else if (scall == MAT_REUSE_MATRIX) {
5069     mat=(Mat_SeqAIJ*)(*A_loc)->data;
5070     ci = mat->i; cj = mat->j; cam = mat->a;
5071     for (i=0; i<am; i++) {
5072       /* off-diagonal portion of A */
5073       ncols_o = bi[i+1] - bi[i];
5074       for (jo=0; jo<ncols_o; jo++) {
5075         col = cmap[*bj];
5076         if (col >= cstart) break;
5077         *cam++ = *ba++; bj++;
5078       }
5079       /* diagonal portion of A */
5080       ncols_d = ai[i+1] - ai[i];
5081       for (j=0; j<ncols_d; j++) *cam++ = *aa++;
5082       /* off-diagonal portion of A */
5083       for (j=jo; j<ncols_o; j++) {
5084         *cam++ = *ba++; bj++;
5085       }
5086     }
5087   } else SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONG,"Invalid MatReuse %d",(int)scall);
5088   ierr = PetscLogEventEnd(MAT_Getlocalmat,A,0,0,0);CHKERRQ(ierr);
5089   PetscFunctionReturn(0);
5090 }
5091 
5092 #undef __FUNCT__
5093 #define __FUNCT__ "MatMPIAIJGetLocalMatCondensed"
5094 /*@C
5095      MatMPIAIJGetLocalMatCondensed - Creates a SeqAIJ matrix from an MPIAIJ matrix by taking all its local rows and NON-ZERO columns
5096 
5097     Not Collective
5098 
5099    Input Parameters:
5100 +    A - the matrix
5101 .    scall - either MAT_INITIAL_MATRIX or MAT_REUSE_MATRIX
5102 -    row, col - index sets of rows and columns to extract (or NULL)
5103 
5104    Output Parameter:
5105 .    A_loc - the local sequential matrix generated
5106 
5107     Level: developer
5108 
5109 .seealso: MatGetOwnershipRange(), MatMPIAIJGetLocalMat()
5110 
5111 @*/
5112 PetscErrorCode  MatMPIAIJGetLocalMatCondensed(Mat A,MatReuse scall,IS *row,IS *col,Mat *A_loc)
5113 {
5114   Mat_MPIAIJ     *a=(Mat_MPIAIJ*)A->data;
5115   PetscErrorCode ierr;
5116   PetscInt       i,start,end,ncols,nzA,nzB,*cmap,imark,*idx;
5117   IS             isrowa,iscola;
5118   Mat            *aloc;
5119   PetscBool      match;
5120 
5121   PetscFunctionBegin;
5122   ierr = PetscObjectTypeCompare((PetscObject)A,MATMPIAIJ,&match);CHKERRQ(ierr);
5123   if (!match) SETERRQ(PetscObjectComm((PetscObject)A), PETSC_ERR_SUP,"Requires MPIAIJ matrix as input");
5124   ierr = PetscLogEventBegin(MAT_Getlocalmatcondensed,A,0,0,0);CHKERRQ(ierr);
5125   if (!row) {
5126     start = A->rmap->rstart; end = A->rmap->rend;
5127     ierr  = ISCreateStride(PETSC_COMM_SELF,end-start,start,1,&isrowa);CHKERRQ(ierr);
5128   } else {
5129     isrowa = *row;
5130   }
5131   if (!col) {
5132     start = A->cmap->rstart;
5133     cmap  = a->garray;
5134     nzA   = a->A->cmap->n;
5135     nzB   = a->B->cmap->n;
5136     ierr  = PetscMalloc((nzA+nzB)*sizeof(PetscInt), &idx);CHKERRQ(ierr);
5137     ncols = 0;
5138     for (i=0; i<nzB; i++) {
5139       if (cmap[i] < start) idx[ncols++] = cmap[i];
5140       else break;
5141     }
5142     imark = i;
5143     for (i=0; i<nzA; i++) idx[ncols++] = start + i;
5144     for (i=imark; i<nzB; i++) idx[ncols++] = cmap[i];
5145     ierr = ISCreateGeneral(PETSC_COMM_SELF,ncols,idx,PETSC_OWN_POINTER,&iscola);CHKERRQ(ierr);
5146   } else {
5147     iscola = *col;
5148   }
5149   if (scall != MAT_INITIAL_MATRIX) {
5150     ierr    = PetscMalloc(sizeof(Mat),&aloc);CHKERRQ(ierr);
5151     aloc[0] = *A_loc;
5152   }
5153   ierr   = MatGetSubMatrices(A,1,&isrowa,&iscola,scall,&aloc);CHKERRQ(ierr);
5154   *A_loc = aloc[0];
5155   ierr   = PetscFree(aloc);CHKERRQ(ierr);
5156   if (!row) {
5157     ierr = ISDestroy(&isrowa);CHKERRQ(ierr);
5158   }
5159   if (!col) {
5160     ierr = ISDestroy(&iscola);CHKERRQ(ierr);
5161   }
5162   ierr = PetscLogEventEnd(MAT_Getlocalmatcondensed,A,0,0,0);CHKERRQ(ierr);
5163   PetscFunctionReturn(0);
5164 }
5165 
5166 #undef __FUNCT__
5167 #define __FUNCT__ "MatGetBrowsOfAcols"
5168 /*@C
5169     MatGetBrowsOfAcols - Creates a SeqAIJ matrix by taking rows of B that equal to nonzero columns of local A
5170 
5171     Collective on Mat
5172 
5173    Input Parameters:
5174 +    A,B - the matrices in mpiaij format
5175 .    scall - either MAT_INITIAL_MATRIX or MAT_REUSE_MATRIX
5176 -    rowb, colb - index sets of rows and columns of B to extract (or NULL)
5177 
5178    Output Parameter:
5179 +    rowb, colb - index sets of rows and columns of B to extract
5180 -    B_seq - the sequential matrix generated
5181 
5182     Level: developer
5183 
5184 @*/
5185 PetscErrorCode  MatGetBrowsOfAcols(Mat A,Mat B,MatReuse scall,IS *rowb,IS *colb,Mat *B_seq)
5186 {
5187   Mat_MPIAIJ     *a=(Mat_MPIAIJ*)A->data;
5188   PetscErrorCode ierr;
5189   PetscInt       *idx,i,start,ncols,nzA,nzB,*cmap,imark;
5190   IS             isrowb,iscolb;
5191   Mat            *bseq=NULL;
5192 
5193   PetscFunctionBegin;
5194   if (A->cmap->rstart != B->rmap->rstart || A->cmap->rend != B->rmap->rend) {
5195     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);
5196   }
5197   ierr = PetscLogEventBegin(MAT_GetBrowsOfAcols,A,B,0,0);CHKERRQ(ierr);
5198 
5199   if (scall == MAT_INITIAL_MATRIX) {
5200     start = A->cmap->rstart;
5201     cmap  = a->garray;
5202     nzA   = a->A->cmap->n;
5203     nzB   = a->B->cmap->n;
5204     ierr  = PetscMalloc((nzA+nzB)*sizeof(PetscInt), &idx);CHKERRQ(ierr);
5205     ncols = 0;
5206     for (i=0; i<nzB; i++) {  /* row < local row index */
5207       if (cmap[i] < start) idx[ncols++] = cmap[i];
5208       else break;
5209     }
5210     imark = i;
5211     for (i=0; i<nzA; i++) idx[ncols++] = start + i;  /* local rows */
5212     for (i=imark; i<nzB; i++) idx[ncols++] = cmap[i]; /* row > local row index */
5213     ierr = ISCreateGeneral(PETSC_COMM_SELF,ncols,idx,PETSC_OWN_POINTER,&isrowb);CHKERRQ(ierr);
5214     ierr = ISCreateStride(PETSC_COMM_SELF,B->cmap->N,0,1,&iscolb);CHKERRQ(ierr);
5215   } else {
5216     if (!rowb || !colb) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_SUP,"IS rowb and colb must be provided for MAT_REUSE_MATRIX");
5217     isrowb  = *rowb; iscolb = *colb;
5218     ierr    = PetscMalloc(sizeof(Mat),&bseq);CHKERRQ(ierr);
5219     bseq[0] = *B_seq;
5220   }
5221   ierr   = MatGetSubMatrices(B,1,&isrowb,&iscolb,scall,&bseq);CHKERRQ(ierr);
5222   *B_seq = bseq[0];
5223   ierr   = PetscFree(bseq);CHKERRQ(ierr);
5224   if (!rowb) {
5225     ierr = ISDestroy(&isrowb);CHKERRQ(ierr);
5226   } else {
5227     *rowb = isrowb;
5228   }
5229   if (!colb) {
5230     ierr = ISDestroy(&iscolb);CHKERRQ(ierr);
5231   } else {
5232     *colb = iscolb;
5233   }
5234   ierr = PetscLogEventEnd(MAT_GetBrowsOfAcols,A,B,0,0);CHKERRQ(ierr);
5235   PetscFunctionReturn(0);
5236 }
5237 
5238 #undef __FUNCT__
5239 #define __FUNCT__ "MatGetBrowsOfAoCols_MPIAIJ"
5240 /*
5241     MatGetBrowsOfAoCols_MPIAIJ - Creates a SeqAIJ matrix by taking rows of B that equal to nonzero columns
5242     of the OFF-DIAGONAL portion of local A
5243 
5244     Collective on Mat
5245 
5246    Input Parameters:
5247 +    A,B - the matrices in mpiaij format
5248 -    scall - either MAT_INITIAL_MATRIX or MAT_REUSE_MATRIX
5249 
5250    Output Parameter:
5251 +    startsj_s - starting point in B's sending j-arrays, saved for MAT_REUSE (or NULL)
5252 .    startsj_r - starting point in B's receiving j-arrays, saved for MAT_REUSE (or NULL)
5253 .    bufa_ptr - array for sending matrix values, saved for MAT_REUSE (or NULL)
5254 -    B_oth - the sequential matrix generated with size aBn=a->B->cmap->n by B->cmap->N
5255 
5256     Level: developer
5257 
5258 */
5259 PetscErrorCode  MatGetBrowsOfAoCols_MPIAIJ(Mat A,Mat B,MatReuse scall,PetscInt **startsj_s,PetscInt **startsj_r,MatScalar **bufa_ptr,Mat *B_oth)
5260 {
5261   VecScatter_MPI_General *gen_to,*gen_from;
5262   PetscErrorCode         ierr;
5263   Mat_MPIAIJ             *a=(Mat_MPIAIJ*)A->data;
5264   Mat_SeqAIJ             *b_oth;
5265   VecScatter             ctx =a->Mvctx;
5266   MPI_Comm               comm;
5267   PetscMPIInt            *rprocs,*sprocs,tag=((PetscObject)ctx)->tag,rank;
5268   PetscInt               *rowlen,*bufj,*bufJ,ncols,aBn=a->B->cmap->n,row,*b_othi,*b_othj;
5269   PetscScalar            *rvalues,*svalues;
5270   MatScalar              *b_otha,*bufa,*bufA;
5271   PetscInt               i,j,k,l,ll,nrecvs,nsends,nrows,*srow,*rstarts,*rstartsj = 0,*sstarts,*sstartsj,len;
5272   MPI_Request            *rwaits = NULL,*swaits = NULL;
5273   MPI_Status             *sstatus,rstatus;
5274   PetscMPIInt            jj;
5275   PetscInt               *cols,sbs,rbs;
5276   PetscScalar            *vals;
5277 
5278   PetscFunctionBegin;
5279   ierr = PetscObjectGetComm((PetscObject)A,&comm);CHKERRQ(ierr);
5280   if (A->cmap->rstart != B->rmap->rstart || A->cmap->rend != B->rmap->rend) {
5281     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);
5282   }
5283   ierr = PetscLogEventBegin(MAT_GetBrowsOfAocols,A,B,0,0);CHKERRQ(ierr);
5284   ierr = MPI_Comm_rank(comm,&rank);CHKERRQ(ierr);
5285 
5286   gen_to   = (VecScatter_MPI_General*)ctx->todata;
5287   gen_from = (VecScatter_MPI_General*)ctx->fromdata;
5288   rvalues  = gen_from->values; /* holds the length of receiving row */
5289   svalues  = gen_to->values;   /* holds the length of sending row */
5290   nrecvs   = gen_from->n;
5291   nsends   = gen_to->n;
5292 
5293   ierr    = PetscMalloc2(nrecvs,MPI_Request,&rwaits,nsends,MPI_Request,&swaits);CHKERRQ(ierr);
5294   srow    = gen_to->indices;    /* local row index to be sent */
5295   sstarts = gen_to->starts;
5296   sprocs  = gen_to->procs;
5297   sstatus = gen_to->sstatus;
5298   sbs     = gen_to->bs;
5299   rstarts = gen_from->starts;
5300   rprocs  = gen_from->procs;
5301   rbs     = gen_from->bs;
5302 
5303   if (!startsj_s || !bufa_ptr) scall = MAT_INITIAL_MATRIX;
5304   if (scall == MAT_INITIAL_MATRIX) {
5305     /* i-array */
5306     /*---------*/
5307     /*  post receives */
5308     for (i=0; i<nrecvs; i++) {
5309       rowlen = (PetscInt*)rvalues + rstarts[i]*rbs;
5310       nrows  = (rstarts[i+1]-rstarts[i])*rbs; /* num of indices to be received */
5311       ierr   = MPI_Irecv(rowlen,nrows,MPIU_INT,rprocs[i],tag,comm,rwaits+i);CHKERRQ(ierr);
5312     }
5313 
5314     /* pack the outgoing message */
5315     ierr = PetscMalloc2(nsends+1,PetscInt,&sstartsj,nrecvs+1,PetscInt,&rstartsj);CHKERRQ(ierr);
5316 
5317     sstartsj[0] = 0;
5318     rstartsj[0] = 0;
5319     len         = 0; /* total length of j or a array to be sent */
5320     k           = 0;
5321     for (i=0; i<nsends; i++) {
5322       rowlen = (PetscInt*)svalues + sstarts[i]*sbs;
5323       nrows  = sstarts[i+1]-sstarts[i]; /* num of block rows */
5324       for (j=0; j<nrows; j++) {
5325         row = srow[k] + B->rmap->range[rank]; /* global row idx */
5326         for (l=0; l<sbs; l++) {
5327           ierr = MatGetRow_MPIAIJ(B,row+l,&ncols,NULL,NULL);CHKERRQ(ierr); /* rowlength */
5328 
5329           rowlen[j*sbs+l] = ncols;
5330 
5331           len += ncols;
5332           ierr = MatRestoreRow_MPIAIJ(B,row+l,&ncols,NULL,NULL);CHKERRQ(ierr);
5333         }
5334         k++;
5335       }
5336       ierr = MPI_Isend(rowlen,nrows*sbs,MPIU_INT,sprocs[i],tag,comm,swaits+i);CHKERRQ(ierr);
5337 
5338       sstartsj[i+1] = len;  /* starting point of (i+1)-th outgoing msg in bufj and bufa */
5339     }
5340     /* recvs and sends of i-array are completed */
5341     i = nrecvs;
5342     while (i--) {
5343       ierr = MPI_Waitany(nrecvs,rwaits,&jj,&rstatus);CHKERRQ(ierr);
5344     }
5345     if (nsends) {ierr = MPI_Waitall(nsends,swaits,sstatus);CHKERRQ(ierr);}
5346 
5347     /* allocate buffers for sending j and a arrays */
5348     ierr = PetscMalloc((len+1)*sizeof(PetscInt),&bufj);CHKERRQ(ierr);
5349     ierr = PetscMalloc((len+1)*sizeof(PetscScalar),&bufa);CHKERRQ(ierr);
5350 
5351     /* create i-array of B_oth */
5352     ierr = PetscMalloc((aBn+2)*sizeof(PetscInt),&b_othi);CHKERRQ(ierr);
5353 
5354     b_othi[0] = 0;
5355     len       = 0; /* total length of j or a array to be received */
5356     k         = 0;
5357     for (i=0; i<nrecvs; i++) {
5358       rowlen = (PetscInt*)rvalues + rstarts[i]*rbs;
5359       nrows  = rbs*(rstarts[i+1]-rstarts[i]); /* num of rows to be recieved */
5360       for (j=0; j<nrows; j++) {
5361         b_othi[k+1] = b_othi[k] + rowlen[j];
5362         len        += rowlen[j]; k++;
5363       }
5364       rstartsj[i+1] = len; /* starting point of (i+1)-th incoming msg in bufj and bufa */
5365     }
5366 
5367     /* allocate space for j and a arrrays of B_oth */
5368     ierr = PetscMalloc((b_othi[aBn]+1)*sizeof(PetscInt),&b_othj);CHKERRQ(ierr);
5369     ierr = PetscMalloc((b_othi[aBn]+1)*sizeof(MatScalar),&b_otha);CHKERRQ(ierr);
5370 
5371     /* j-array */
5372     /*---------*/
5373     /*  post receives of j-array */
5374     for (i=0; i<nrecvs; i++) {
5375       nrows = rstartsj[i+1]-rstartsj[i]; /* length of the msg received */
5376       ierr  = MPI_Irecv(b_othj+rstartsj[i],nrows,MPIU_INT,rprocs[i],tag,comm,rwaits+i);CHKERRQ(ierr);
5377     }
5378 
5379     /* pack the outgoing message j-array */
5380     k = 0;
5381     for (i=0; i<nsends; i++) {
5382       nrows = sstarts[i+1]-sstarts[i]; /* num of block rows */
5383       bufJ  = bufj+sstartsj[i];
5384       for (j=0; j<nrows; j++) {
5385         row = srow[k++] + B->rmap->range[rank];  /* global row idx */
5386         for (ll=0; ll<sbs; ll++) {
5387           ierr = MatGetRow_MPIAIJ(B,row+ll,&ncols,&cols,NULL);CHKERRQ(ierr);
5388           for (l=0; l<ncols; l++) {
5389             *bufJ++ = cols[l];
5390           }
5391           ierr = MatRestoreRow_MPIAIJ(B,row+ll,&ncols,&cols,NULL);CHKERRQ(ierr);
5392         }
5393       }
5394       ierr = MPI_Isend(bufj+sstartsj[i],sstartsj[i+1]-sstartsj[i],MPIU_INT,sprocs[i],tag,comm,swaits+i);CHKERRQ(ierr);
5395     }
5396 
5397     /* recvs and sends of j-array are completed */
5398     i = nrecvs;
5399     while (i--) {
5400       ierr = MPI_Waitany(nrecvs,rwaits,&jj,&rstatus);CHKERRQ(ierr);
5401     }
5402     if (nsends) {ierr = MPI_Waitall(nsends,swaits,sstatus);CHKERRQ(ierr);}
5403   } else if (scall == MAT_REUSE_MATRIX) {
5404     sstartsj = *startsj_s;
5405     rstartsj = *startsj_r;
5406     bufa     = *bufa_ptr;
5407     b_oth    = (Mat_SeqAIJ*)(*B_oth)->data;
5408     b_otha   = b_oth->a;
5409   } else SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE, "Matrix P does not posses an object container");
5410 
5411   /* a-array */
5412   /*---------*/
5413   /*  post receives of a-array */
5414   for (i=0; i<nrecvs; i++) {
5415     nrows = rstartsj[i+1]-rstartsj[i]; /* length of the msg received */
5416     ierr  = MPI_Irecv(b_otha+rstartsj[i],nrows,MPIU_SCALAR,rprocs[i],tag,comm,rwaits+i);CHKERRQ(ierr);
5417   }
5418 
5419   /* pack the outgoing message a-array */
5420   k = 0;
5421   for (i=0; i<nsends; i++) {
5422     nrows = sstarts[i+1]-sstarts[i]; /* num of block rows */
5423     bufA  = bufa+sstartsj[i];
5424     for (j=0; j<nrows; j++) {
5425       row = srow[k++] + B->rmap->range[rank];  /* global row idx */
5426       for (ll=0; ll<sbs; ll++) {
5427         ierr = MatGetRow_MPIAIJ(B,row+ll,&ncols,NULL,&vals);CHKERRQ(ierr);
5428         for (l=0; l<ncols; l++) {
5429           *bufA++ = vals[l];
5430         }
5431         ierr = MatRestoreRow_MPIAIJ(B,row+ll,&ncols,NULL,&vals);CHKERRQ(ierr);
5432       }
5433     }
5434     ierr = MPI_Isend(bufa+sstartsj[i],sstartsj[i+1]-sstartsj[i],MPIU_SCALAR,sprocs[i],tag,comm,swaits+i);CHKERRQ(ierr);
5435   }
5436   /* recvs and sends of a-array are completed */
5437   i = nrecvs;
5438   while (i--) {
5439     ierr = MPI_Waitany(nrecvs,rwaits,&jj,&rstatus);CHKERRQ(ierr);
5440   }
5441   if (nsends) {ierr = MPI_Waitall(nsends,swaits,sstatus);CHKERRQ(ierr);}
5442   ierr = PetscFree2(rwaits,swaits);CHKERRQ(ierr);
5443 
5444   if (scall == MAT_INITIAL_MATRIX) {
5445     /* put together the new matrix */
5446     ierr = MatCreateSeqAIJWithArrays(PETSC_COMM_SELF,aBn,B->cmap->N,b_othi,b_othj,b_otha,B_oth);CHKERRQ(ierr);
5447 
5448     /* MatCreateSeqAIJWithArrays flags matrix so PETSc doesn't free the user's arrays. */
5449     /* Since these are PETSc arrays, change flags to free them as necessary. */
5450     b_oth          = (Mat_SeqAIJ*)(*B_oth)->data;
5451     b_oth->free_a  = PETSC_TRUE;
5452     b_oth->free_ij = PETSC_TRUE;
5453     b_oth->nonew   = 0;
5454 
5455     ierr = PetscFree(bufj);CHKERRQ(ierr);
5456     if (!startsj_s || !bufa_ptr) {
5457       ierr = PetscFree2(sstartsj,rstartsj);CHKERRQ(ierr);
5458       ierr = PetscFree(bufa_ptr);CHKERRQ(ierr);
5459     } else {
5460       *startsj_s = sstartsj;
5461       *startsj_r = rstartsj;
5462       *bufa_ptr  = bufa;
5463     }
5464   }
5465   ierr = PetscLogEventEnd(MAT_GetBrowsOfAocols,A,B,0,0);CHKERRQ(ierr);
5466   PetscFunctionReturn(0);
5467 }
5468 
5469 #undef __FUNCT__
5470 #define __FUNCT__ "MatGetCommunicationStructs"
5471 /*@C
5472   MatGetCommunicationStructs - Provides access to the communication structures used in matrix-vector multiplication.
5473 
5474   Not Collective
5475 
5476   Input Parameters:
5477 . A - The matrix in mpiaij format
5478 
5479   Output Parameter:
5480 + lvec - The local vector holding off-process values from the argument to a matrix-vector product
5481 . colmap - A map from global column index to local index into lvec
5482 - multScatter - A scatter from the argument of a matrix-vector product to lvec
5483 
5484   Level: developer
5485 
5486 @*/
5487 #if defined(PETSC_USE_CTABLE)
5488 PetscErrorCode  MatGetCommunicationStructs(Mat A, Vec *lvec, PetscTable *colmap, VecScatter *multScatter)
5489 #else
5490 PetscErrorCode  MatGetCommunicationStructs(Mat A, Vec *lvec, PetscInt *colmap[], VecScatter *multScatter)
5491 #endif
5492 {
5493   Mat_MPIAIJ *a;
5494 
5495   PetscFunctionBegin;
5496   PetscValidHeaderSpecific(A, MAT_CLASSID, 1);
5497   PetscValidPointer(lvec, 2);
5498   PetscValidPointer(colmap, 3);
5499   PetscValidPointer(multScatter, 4);
5500   a = (Mat_MPIAIJ*) A->data;
5501   if (lvec) *lvec = a->lvec;
5502   if (colmap) *colmap = a->colmap;
5503   if (multScatter) *multScatter = a->Mvctx;
5504   PetscFunctionReturn(0);
5505 }
5506 
5507 PETSC_EXTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJCRL(Mat,MatType,MatReuse,Mat*);
5508 PETSC_EXTERN PetscErrorCode MatConvert_MPIAIJ_MPIAIJPERM(Mat,MatType,MatReuse,Mat*);
5509 PETSC_EXTERN PetscErrorCode MatConvert_MPIAIJ_MPISBAIJ(Mat,MatType,MatReuse,Mat*);
5510 
5511 #undef __FUNCT__
5512 #define __FUNCT__ "MatMatMultNumeric_MPIDense_MPIAIJ"
5513 /*
5514     Computes (B'*A')' since computing B*A directly is untenable
5515 
5516                n                       p                          p
5517         (              )       (              )         (                  )
5518       m (      A       )  *  n (       B      )   =   m (         C        )
5519         (              )       (              )         (                  )
5520 
5521 */
5522 PetscErrorCode MatMatMultNumeric_MPIDense_MPIAIJ(Mat A,Mat B,Mat C)
5523 {
5524   PetscErrorCode ierr;
5525   Mat            At,Bt,Ct;
5526 
5527   PetscFunctionBegin;
5528   ierr = MatTranspose(A,MAT_INITIAL_MATRIX,&At);CHKERRQ(ierr);
5529   ierr = MatTranspose(B,MAT_INITIAL_MATRIX,&Bt);CHKERRQ(ierr);
5530   ierr = MatMatMult(Bt,At,MAT_INITIAL_MATRIX,1.0,&Ct);CHKERRQ(ierr);
5531   ierr = MatDestroy(&At);CHKERRQ(ierr);
5532   ierr = MatDestroy(&Bt);CHKERRQ(ierr);
5533   ierr = MatTranspose(Ct,MAT_REUSE_MATRIX,&C);CHKERRQ(ierr);
5534   ierr = MatDestroy(&Ct);CHKERRQ(ierr);
5535   PetscFunctionReturn(0);
5536 }
5537 
5538 #undef __FUNCT__
5539 #define __FUNCT__ "MatMatMultSymbolic_MPIDense_MPIAIJ"
5540 PetscErrorCode MatMatMultSymbolic_MPIDense_MPIAIJ(Mat A,Mat B,PetscReal fill,Mat *C)
5541 {
5542   PetscErrorCode ierr;
5543   PetscInt       m=A->rmap->n,n=B->cmap->n;
5544   Mat            Cmat;
5545 
5546   PetscFunctionBegin;
5547   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);
5548   ierr = MatCreate(PetscObjectComm((PetscObject)A),&Cmat);CHKERRQ(ierr);
5549   ierr = MatSetSizes(Cmat,m,n,PETSC_DETERMINE,PETSC_DETERMINE);CHKERRQ(ierr);
5550   ierr = MatSetBlockSizes(Cmat,A->rmap->bs,B->cmap->bs);CHKERRQ(ierr);
5551   ierr = MatSetType(Cmat,MATMPIDENSE);CHKERRQ(ierr);
5552   ierr = MatMPIDenseSetPreallocation(Cmat,NULL);CHKERRQ(ierr);
5553   ierr = MatAssemblyBegin(Cmat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
5554   ierr = MatAssemblyEnd(Cmat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
5555 
5556   Cmat->ops->matmultnumeric = MatMatMultNumeric_MPIDense_MPIAIJ;
5557 
5558   *C = Cmat;
5559   PetscFunctionReturn(0);
5560 }
5561 
5562 /* ----------------------------------------------------------------*/
5563 #undef __FUNCT__
5564 #define __FUNCT__ "MatMatMult_MPIDense_MPIAIJ"
5565 PetscErrorCode MatMatMult_MPIDense_MPIAIJ(Mat A,Mat B,MatReuse scall,PetscReal fill,Mat *C)
5566 {
5567   PetscErrorCode ierr;
5568 
5569   PetscFunctionBegin;
5570   if (scall == MAT_INITIAL_MATRIX) {
5571     ierr = MatMatMultSymbolic_MPIDense_MPIAIJ(A,B,fill,C);CHKERRQ(ierr);
5572   }
5573   ierr = MatMatMultNumeric_MPIDense_MPIAIJ(A,B,*C);CHKERRQ(ierr);
5574   PetscFunctionReturn(0);
5575 }
5576 
5577 #if defined(PETSC_HAVE_MUMPS)
5578 PETSC_EXTERN PetscErrorCode MatGetFactor_aij_mumps(Mat,MatFactorType,Mat*);
5579 #endif
5580 #if defined(PETSC_HAVE_PASTIX)
5581 PETSC_EXTERN PetscErrorCode MatGetFactor_mpiaij_pastix(Mat,MatFactorType,Mat*);
5582 #endif
5583 #if defined(PETSC_HAVE_SUPERLU_DIST)
5584 PETSC_EXTERN PetscErrorCode MatGetFactor_mpiaij_superlu_dist(Mat,MatFactorType,Mat*);
5585 #endif
5586 #if defined(PETSC_HAVE_CLIQUE)
5587 PETSC_EXTERN PetscErrorCode MatGetFactor_aij_clique(Mat,MatFactorType,Mat*);
5588 #endif
5589 
5590 /*MC
5591    MATMPIAIJ - MATMPIAIJ = "mpiaij" - A matrix type to be used for parallel sparse matrices.
5592 
5593    Options Database Keys:
5594 . -mat_type mpiaij - sets the matrix type to "mpiaij" during a call to MatSetFromOptions()
5595 
5596   Level: beginner
5597 
5598 .seealso: MatCreateAIJ()
5599 M*/
5600 
5601 #undef __FUNCT__
5602 #define __FUNCT__ "MatCreate_MPIAIJ"
5603 PETSC_EXTERN PetscErrorCode MatCreate_MPIAIJ(Mat B)
5604 {
5605   Mat_MPIAIJ     *b;
5606   PetscErrorCode ierr;
5607   PetscMPIInt    size;
5608 
5609   PetscFunctionBegin;
5610   ierr = MPI_Comm_size(PetscObjectComm((PetscObject)B),&size);CHKERRQ(ierr);
5611 
5612   ierr          = PetscNewLog(B,Mat_MPIAIJ,&b);CHKERRQ(ierr);
5613   B->data       = (void*)b;
5614   ierr          = PetscMemcpy(B->ops,&MatOps_Values,sizeof(struct _MatOps));CHKERRQ(ierr);
5615   B->assembled  = PETSC_FALSE;
5616   B->insertmode = NOT_SET_VALUES;
5617   b->size       = size;
5618 
5619   ierr = MPI_Comm_rank(PetscObjectComm((PetscObject)B),&b->rank);CHKERRQ(ierr);
5620 
5621   /* build cache for off array entries formed */
5622   ierr = MatStashCreate_Private(PetscObjectComm((PetscObject)B),1,&B->stash);CHKERRQ(ierr);
5623 
5624   b->donotstash  = PETSC_FALSE;
5625   b->colmap      = 0;
5626   b->garray      = 0;
5627   b->roworiented = PETSC_TRUE;
5628 
5629   /* stuff used for matrix vector multiply */
5630   b->lvec  = NULL;
5631   b->Mvctx = NULL;
5632 
5633   /* stuff for MatGetRow() */
5634   b->rowindices   = 0;
5635   b->rowvalues    = 0;
5636   b->getrowactive = PETSC_FALSE;
5637 
5638   /* flexible pointer used in CUSP/CUSPARSE classes */
5639   b->spptr = NULL;
5640 
5641 #if defined(PETSC_HAVE_MUMPS)
5642   ierr = PetscObjectComposeFunction((PetscObject)B,"MatGetFactor_mumps_C","MatGetFactor_aij_mumps",MatGetFactor_aij_mumps);CHKERRQ(ierr);
5643 #endif
5644 #if defined(PETSC_HAVE_PASTIX)
5645   ierr = PetscObjectComposeFunction((PetscObject)B,"MatGetFactor_pastix_C","MatGetFactor_mpiaij_pastix",MatGetFactor_mpiaij_pastix);CHKERRQ(ierr);
5646 #endif
5647 #if defined(PETSC_HAVE_SUPERLU_DIST)
5648   ierr = PetscObjectComposeFunction((PetscObject)B,"MatGetFactor_superlu_dist_C","MatGetFactor_mpiaij_superlu_dist",MatGetFactor_mpiaij_superlu_dist);CHKERRQ(ierr);
5649 #endif
5650 #if defined(PETSC_HAVE_CLIQUE)
5651   ierr = PetscObjectComposeFunction((PetscObject)B,"MatGetFactor_clique_C","MatGetFactor_aij_clique",MatGetFactor_aij_clique);CHKERRQ(ierr);
5652 #endif
5653   ierr = PetscObjectComposeFunction((PetscObject)B,"MatStoreValues_C","MatStoreValues_MPIAIJ",MatStoreValues_MPIAIJ);CHKERRQ(ierr);
5654   ierr = PetscObjectComposeFunction((PetscObject)B,"MatRetrieveValues_C","MatRetrieveValues_MPIAIJ",MatRetrieveValues_MPIAIJ);CHKERRQ(ierr);
5655   ierr = PetscObjectComposeFunction((PetscObject)B,"MatGetDiagonalBlock_C","MatGetDiagonalBlock_MPIAIJ",MatGetDiagonalBlock_MPIAIJ);CHKERRQ(ierr);
5656   ierr = PetscObjectComposeFunction((PetscObject)B,"MatIsTranspose_C","MatIsTranspose_MPIAIJ",MatIsTranspose_MPIAIJ);CHKERRQ(ierr);
5657   ierr = PetscObjectComposeFunction((PetscObject)B,"MatMPIAIJSetPreallocation_C","MatMPIAIJSetPreallocation_MPIAIJ",MatMPIAIJSetPreallocation_MPIAIJ);CHKERRQ(ierr);
5658   ierr = PetscObjectComposeFunction((PetscObject)B,"MatMPIAIJSetPreallocationCSR_C","MatMPIAIJSetPreallocationCSR_MPIAIJ",MatMPIAIJSetPreallocationCSR_MPIAIJ);CHKERRQ(ierr);
5659   ierr = PetscObjectComposeFunction((PetscObject)B,"MatDiagonalScaleLocal_C","MatDiagonalScaleLocal_MPIAIJ",MatDiagonalScaleLocal_MPIAIJ);CHKERRQ(ierr);
5660   ierr = PetscObjectComposeFunction((PetscObject)B,"MatConvert_mpiaij_mpiaijperm_C","MatConvert_MPIAIJ_MPIAIJPERM",MatConvert_MPIAIJ_MPIAIJPERM);CHKERRQ(ierr);
5661   ierr = PetscObjectComposeFunction((PetscObject)B,"MatConvert_mpiaij_mpiaijcrl_C","MatConvert_MPIAIJ_MPIAIJCRL",MatConvert_MPIAIJ_MPIAIJCRL);CHKERRQ(ierr);
5662   ierr = PetscObjectComposeFunction((PetscObject)B,"MatConvert_mpiaij_mpisbaij_C","MatConvert_MPIAIJ_MPISBAIJ",MatConvert_MPIAIJ_MPISBAIJ);CHKERRQ(ierr);
5663   ierr = PetscObjectComposeFunction((PetscObject)B,"MatMatMult_mpidense_mpiaij_C","MatMatMult_MPIDense_MPIAIJ",MatMatMult_MPIDense_MPIAIJ);CHKERRQ(ierr);
5664   ierr = PetscObjectComposeFunction((PetscObject)B,"MatMatMultSymbolic_mpidense_mpiaij_C","MatMatMultSymbolic_MPIDense_MPIAIJ",MatMatMultSymbolic_MPIDense_MPIAIJ);CHKERRQ(ierr);
5665   ierr = PetscObjectComposeFunction((PetscObject)B,"MatMatMultNumeric_mpidense_mpiaij_C","MatMatMultNumeric_MPIDense_MPIAIJ",MatMatMultNumeric_MPIDense_MPIAIJ);CHKERRQ(ierr);
5666   ierr = PetscObjectChangeTypeName((PetscObject)B,MATMPIAIJ);CHKERRQ(ierr);
5667   PetscFunctionReturn(0);
5668 }
5669 
5670 #undef __FUNCT__
5671 #define __FUNCT__ "MatCreateMPIAIJWithSplitArrays"
5672 /*@
5673      MatCreateMPIAIJWithSplitArrays - creates a MPI AIJ matrix using arrays that contain the "diagonal"
5674          and "off-diagonal" part of the matrix in CSR format.
5675 
5676    Collective on MPI_Comm
5677 
5678    Input Parameters:
5679 +  comm - MPI communicator
5680 .  m - number of local rows (Cannot be PETSC_DECIDE)
5681 .  n - This value should be the same as the local size used in creating the
5682        x vector for the matrix-vector product y = Ax. (or PETSC_DECIDE to have
5683        calculated if N is given) For square matrices n is almost always m.
5684 .  M - number of global rows (or PETSC_DETERMINE to have calculated if m is given)
5685 .  N - number of global columns (or PETSC_DETERMINE to have calculated if n is given)
5686 .   i - row indices for "diagonal" portion of matrix
5687 .   j - column indices
5688 .   a - matrix values
5689 .   oi - row indices for "off-diagonal" portion of matrix
5690 .   oj - column indices
5691 -   oa - matrix values
5692 
5693    Output Parameter:
5694 .   mat - the matrix
5695 
5696    Level: advanced
5697 
5698    Notes:
5699        The i, j, and a arrays ARE NOT copied by this routine into the internal format used by PETSc. The user
5700        must free the arrays once the matrix has been destroyed and not before.
5701 
5702        The i and j indices are 0 based
5703 
5704        See MatCreateAIJ() for the definition of "diagonal" and "off-diagonal" portion of the matrix
5705 
5706        This sets local rows and cannot be used to set off-processor values.
5707 
5708        Use of this routine is discouraged because it is inflexible and cumbersome to use. It is extremely rare that a
5709        legacy application natively assembles into exactly this split format. The code to do so is nontrivial and does
5710        not easily support in-place reassembly. It is recommended to use MatSetValues() (or a variant thereof) because
5711        the resulting assembly is easier to implement, will work with any matrix format, and the user does not have to
5712        keep track of the underlying array. Use MatSetOption(A,MAT_IGNORE_OFF_PROC_ENTRIES,PETSC_TRUE) to disable all
5713        communication if it is known that only local entries will be set.
5714 
5715 .keywords: matrix, aij, compressed row, sparse, parallel
5716 
5717 .seealso: MatCreate(), MatCreateSeqAIJ(), MatSetValues(), MatMPIAIJSetPreallocation(), MatMPIAIJSetPreallocationCSR(),
5718           MPIAIJ, MatCreateAIJ(), MatCreateMPIAIJWithArrays()
5719 @*/
5720 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)
5721 {
5722   PetscErrorCode ierr;
5723   Mat_MPIAIJ     *maij;
5724 
5725   PetscFunctionBegin;
5726   if (m < 0) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"local number of rows (m) cannot be PETSC_DECIDE, or negative");
5727   if (i[0]) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"i (row indices) must start with 0");
5728   if (oi[0]) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"oi (row indices) must start with 0");
5729   ierr = MatCreate(comm,mat);CHKERRQ(ierr);
5730   ierr = MatSetSizes(*mat,m,n,M,N);CHKERRQ(ierr);
5731   ierr = MatSetType(*mat,MATMPIAIJ);CHKERRQ(ierr);
5732   maij = (Mat_MPIAIJ*) (*mat)->data;
5733 
5734   (*mat)->preallocated = PETSC_TRUE;
5735 
5736   ierr = PetscLayoutSetUp((*mat)->rmap);CHKERRQ(ierr);
5737   ierr = PetscLayoutSetUp((*mat)->cmap);CHKERRQ(ierr);
5738 
5739   ierr = MatCreateSeqAIJWithArrays(PETSC_COMM_SELF,m,n,i,j,a,&maij->A);CHKERRQ(ierr);
5740   ierr = MatCreateSeqAIJWithArrays(PETSC_COMM_SELF,m,(*mat)->cmap->N,oi,oj,oa,&maij->B);CHKERRQ(ierr);
5741 
5742   ierr = MatAssemblyBegin(maij->A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
5743   ierr = MatAssemblyEnd(maij->A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
5744   ierr = MatAssemblyBegin(maij->B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
5745   ierr = MatAssemblyEnd(maij->B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
5746 
5747   ierr = MatAssemblyBegin(*mat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
5748   ierr = MatAssemblyEnd(*mat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
5749   ierr = MatSetOption(*mat,MAT_NEW_NONZERO_LOCATION_ERR,PETSC_TRUE);CHKERRQ(ierr);
5750   PetscFunctionReturn(0);
5751 }
5752 
5753 /*
5754     Special version for direct calls from Fortran
5755 */
5756 #include <petsc-private/fortranimpl.h>
5757 
5758 #if defined(PETSC_HAVE_FORTRAN_CAPS)
5759 #define matsetvaluesmpiaij_ MATSETVALUESMPIAIJ
5760 #elif !defined(PETSC_HAVE_FORTRAN_UNDERSCORE)
5761 #define matsetvaluesmpiaij_ matsetvaluesmpiaij
5762 #endif
5763 
5764 /* Change these macros so can be used in void function */
5765 #undef CHKERRQ
5766 #define CHKERRQ(ierr) CHKERRABORT(PETSC_COMM_WORLD,ierr)
5767 #undef SETERRQ2
5768 #define SETERRQ2(comm,ierr,b,c,d) CHKERRABORT(comm,ierr)
5769 #undef SETERRQ3
5770 #define SETERRQ3(comm,ierr,b,c,d,e) CHKERRABORT(comm,ierr)
5771 #undef SETERRQ
5772 #define SETERRQ(c,ierr,b) CHKERRABORT(c,ierr)
5773 
5774 #undef __FUNCT__
5775 #define __FUNCT__ "matsetvaluesmpiaij_"
5776 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)
5777 {
5778   Mat            mat  = *mmat;
5779   PetscInt       m    = *mm, n = *mn;
5780   InsertMode     addv = *maddv;
5781   Mat_MPIAIJ     *aij = (Mat_MPIAIJ*)mat->data;
5782   PetscScalar    value;
5783   PetscErrorCode ierr;
5784 
5785   MatCheckPreallocated(mat,1);
5786   if (mat->insertmode == NOT_SET_VALUES) mat->insertmode = addv;
5787 
5788 #if defined(PETSC_USE_DEBUG)
5789   else if (mat->insertmode != addv) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"Cannot mix add values and insert values");
5790 #endif
5791   {
5792     PetscInt  i,j,rstart  = mat->rmap->rstart,rend = mat->rmap->rend;
5793     PetscInt  cstart      = mat->cmap->rstart,cend = mat->cmap->rend,row,col;
5794     PetscBool roworiented = aij->roworiented;
5795 
5796     /* Some Variables required in the macro */
5797     Mat        A                 = aij->A;
5798     Mat_SeqAIJ *a                = (Mat_SeqAIJ*)A->data;
5799     PetscInt   *aimax            = a->imax,*ai = a->i,*ailen = a->ilen,*aj = a->j;
5800     MatScalar  *aa               = a->a;
5801     PetscBool  ignorezeroentries = (((a->ignorezeroentries)&&(addv==ADD_VALUES)) ? PETSC_TRUE : PETSC_FALSE);
5802     Mat        B                 = aij->B;
5803     Mat_SeqAIJ *b                = (Mat_SeqAIJ*)B->data;
5804     PetscInt   *bimax            = b->imax,*bi = b->i,*bilen = b->ilen,*bj = b->j,bm = aij->B->rmap->n,am = aij->A->rmap->n;
5805     MatScalar  *ba               = b->a;
5806 
5807     PetscInt  *rp1,*rp2,ii,nrow1,nrow2,_i,rmax1,rmax2,N,low1,high1,low2,high2,t,lastcol1,lastcol2;
5808     PetscInt  nonew = a->nonew;
5809     MatScalar *ap1,*ap2;
5810 
5811     PetscFunctionBegin;
5812     for (i=0; i<m; i++) {
5813       if (im[i] < 0) continue;
5814 #if defined(PETSC_USE_DEBUG)
5815       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);
5816 #endif
5817       if (im[i] >= rstart && im[i] < rend) {
5818         row      = im[i] - rstart;
5819         lastcol1 = -1;
5820         rp1      = aj + ai[row];
5821         ap1      = aa + ai[row];
5822         rmax1    = aimax[row];
5823         nrow1    = ailen[row];
5824         low1     = 0;
5825         high1    = nrow1;
5826         lastcol2 = -1;
5827         rp2      = bj + bi[row];
5828         ap2      = ba + bi[row];
5829         rmax2    = bimax[row];
5830         nrow2    = bilen[row];
5831         low2     = 0;
5832         high2    = nrow2;
5833 
5834         for (j=0; j<n; j++) {
5835           if (roworiented) value = v[i*n+j];
5836           else value = v[i+j*m];
5837           if (ignorezeroentries && value == 0.0 && (addv == ADD_VALUES)) continue;
5838           if (in[j] >= cstart && in[j] < cend) {
5839             col = in[j] - cstart;
5840             MatSetValues_SeqAIJ_A_Private(row,col,value,addv);
5841           } else if (in[j] < 0) continue;
5842 #if defined(PETSC_USE_DEBUG)
5843           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);
5844 #endif
5845           else {
5846             if (mat->was_assembled) {
5847               if (!aij->colmap) {
5848                 ierr = MatCreateColmap_MPIAIJ_Private(mat);CHKERRQ(ierr);
5849               }
5850 #if defined(PETSC_USE_CTABLE)
5851               ierr = PetscTableFind(aij->colmap,in[j]+1,&col);CHKERRQ(ierr);
5852               col--;
5853 #else
5854               col = aij->colmap[in[j]] - 1;
5855 #endif
5856               if (col < 0 && !((Mat_SeqAIJ*)(aij->A->data))->nonew) {
5857                 ierr = MatDisAssemble_MPIAIJ(mat);CHKERRQ(ierr);
5858                 col  =  in[j];
5859                 /* Reinitialize the variables required by MatSetValues_SeqAIJ_B_Private() */
5860                 B     = aij->B;
5861                 b     = (Mat_SeqAIJ*)B->data;
5862                 bimax = b->imax; bi = b->i; bilen = b->ilen; bj = b->j;
5863                 rp2   = bj + bi[row];
5864                 ap2   = ba + bi[row];
5865                 rmax2 = bimax[row];
5866                 nrow2 = bilen[row];
5867                 low2  = 0;
5868                 high2 = nrow2;
5869                 bm    = aij->B->rmap->n;
5870                 ba    = b->a;
5871               }
5872             } else col = in[j];
5873             MatSetValues_SeqAIJ_B_Private(row,col,value,addv);
5874           }
5875         }
5876       } else if (!aij->donotstash) {
5877         if (roworiented) {
5878           ierr = MatStashValuesRow_Private(&mat->stash,im[i],n,in,v+i*n,(PetscBool)(ignorezeroentries && (addv == ADD_VALUES)));CHKERRQ(ierr);
5879         } else {
5880           ierr = MatStashValuesCol_Private(&mat->stash,im[i],n,in,v+i,m,(PetscBool)(ignorezeroentries && (addv == ADD_VALUES)));CHKERRQ(ierr);
5881         }
5882       }
5883     }
5884   }
5885   PetscFunctionReturnVoid();
5886 }
5887 
5888