xref: /petsc/src/mat/impls/sbaij/mpi/mpisbaij.c (revision dd6ea824153195eb348b944549ad76bc75662a78)
1 #define PETSCMAT_DLL
2 
3 #include "src/mat/impls/baij/mpi/mpibaij.h"    /*I "petscmat.h" I*/
4 #include "mpisbaij.h"
5 #include "src/mat/impls/sbaij/seq/sbaij.h"
6 
7 EXTERN PetscErrorCode MatSetUpMultiply_MPISBAIJ(Mat);
8 EXTERN PetscErrorCode MatSetUpMultiply_MPISBAIJ_2comm(Mat);
9 EXTERN PetscErrorCode DisAssemble_MPISBAIJ(Mat);
10 EXTERN PetscErrorCode MatIncreaseOverlap_MPISBAIJ(Mat,PetscInt,IS[],PetscInt);
11 EXTERN PetscErrorCode MatGetValues_SeqSBAIJ(Mat,PetscInt,const PetscInt[],PetscInt,const PetscInt[],PetscScalar []);
12 EXTERN PetscErrorCode MatGetValues_SeqBAIJ(Mat,PetscInt,const PetscInt[],PetscInt,const PetscInt[],PetscScalar []);
13 EXTERN PetscErrorCode MatSetValues_SeqSBAIJ(Mat,PetscInt,const PetscInt [],PetscInt,const PetscInt [],const PetscScalar [],InsertMode);
14 EXTERN PetscErrorCode MatSetValuesBlocked_SeqSBAIJ(Mat,PetscInt,const PetscInt[],PetscInt,const PetscInt[],const PetscScalar[],InsertMode);
15 EXTERN PetscErrorCode MatSetValuesBlocked_SeqBAIJ(Mat,PetscInt,const PetscInt[],PetscInt,const PetscInt[],const PetscScalar[],InsertMode);
16 EXTERN PetscErrorCode MatGetRow_SeqSBAIJ(Mat,PetscInt,PetscInt*,PetscInt**,PetscScalar**);
17 EXTERN PetscErrorCode MatRestoreRow_SeqSBAIJ(Mat,PetscInt,PetscInt*,PetscInt**,PetscScalar**);
18 EXTERN PetscErrorCode MatZeroRows_SeqSBAIJ(Mat,IS,PetscScalar*);
19 EXTERN PetscErrorCode MatZeroRows_SeqBAIJ(Mat,IS,PetscScalar *);
20 EXTERN PetscErrorCode MatGetRowMaxAbs_MPISBAIJ(Mat,Vec,PetscInt[]);
21 EXTERN PetscErrorCode MatRelax_MPISBAIJ(Mat,Vec,PetscReal,MatSORType,PetscReal,PetscInt,PetscInt,Vec);
22 
23 EXTERN_C_BEGIN
24 #undef __FUNCT__
25 #define __FUNCT__ "MatStoreValues_MPISBAIJ"
26 PetscErrorCode PETSCMAT_DLLEXPORT MatStoreValues_MPISBAIJ(Mat mat)
27 {
28   Mat_MPISBAIJ   *aij = (Mat_MPISBAIJ *)mat->data;
29   PetscErrorCode ierr;
30 
31   PetscFunctionBegin;
32   ierr = MatStoreValues(aij->A);CHKERRQ(ierr);
33   ierr = MatStoreValues(aij->B);CHKERRQ(ierr);
34   PetscFunctionReturn(0);
35 }
36 EXTERN_C_END
37 
38 EXTERN_C_BEGIN
39 #undef __FUNCT__
40 #define __FUNCT__ "MatRetrieveValues_MPISBAIJ"
41 PetscErrorCode PETSCMAT_DLLEXPORT MatRetrieveValues_MPISBAIJ(Mat mat)
42 {
43   Mat_MPISBAIJ   *aij = (Mat_MPISBAIJ *)mat->data;
44   PetscErrorCode ierr;
45 
46   PetscFunctionBegin;
47   ierr = MatRetrieveValues(aij->A);CHKERRQ(ierr);
48   ierr = MatRetrieveValues(aij->B);CHKERRQ(ierr);
49   PetscFunctionReturn(0);
50 }
51 EXTERN_C_END
52 
53 
54 #define CHUNKSIZE  10
55 
56 #define  MatSetValues_SeqSBAIJ_A_Private(row,col,value,addv) \
57 { \
58  \
59     brow = row/bs;  \
60     rp   = aj + ai[brow]; ap = aa + bs2*ai[brow]; \
61     rmax = aimax[brow]; nrow = ailen[brow]; \
62       bcol = col/bs; \
63       ridx = row % bs; cidx = col % bs; \
64       low = 0; high = nrow; \
65       while (high-low > 3) { \
66         t = (low+high)/2; \
67         if (rp[t] > bcol) high = t; \
68         else              low  = t; \
69       } \
70       for (_i=low; _i<high; _i++) { \
71         if (rp[_i] > bcol) break; \
72         if (rp[_i] == bcol) { \
73           bap  = ap +  bs2*_i + bs*cidx + ridx; \
74           if (addv == ADD_VALUES) *bap += value;  \
75           else                    *bap  = value;  \
76           goto a_noinsert; \
77         } \
78       } \
79       if (a->nonew == 1) goto a_noinsert; \
80       if (a->nonew == -1) SETERRQ2(PETSC_ERR_ARG_OUTOFRANGE,"Inserting a new nonzero (%D, %D) into matrix", row, col); \
81       MatSeqXAIJReallocateAIJ(A,a->mbs,bs2,nrow,brow,bcol,rmax,aa,ai,aj,rp,ap,aimax,a->nonew,MatScalar); \
82       N = nrow++ - 1;  \
83       /* shift up all the later entries in this row */ \
84       for (ii=N; ii>=_i; ii--) { \
85         rp[ii+1] = rp[ii]; \
86         ierr = PetscMemcpy(ap+bs2*(ii+1),ap+bs2*(ii),bs2*sizeof(MatScalar));CHKERRQ(ierr); \
87       } \
88       if (N>=_i) { ierr = PetscMemzero(ap+bs2*_i,bs2*sizeof(MatScalar));CHKERRQ(ierr); }  \
89       rp[_i]                      = bcol;  \
90       ap[bs2*_i + bs*cidx + ridx] = value;  \
91       a_noinsert:; \
92     ailen[brow] = nrow; \
93 }
94 #ifndef MatSetValues_SeqBAIJ_B_Private
95 #define  MatSetValues_SeqSBAIJ_B_Private(row,col,value,addv) \
96 { \
97     brow = row/bs;  \
98     rp   = bj + bi[brow]; ap = ba + bs2*bi[brow]; \
99     rmax = bimax[brow]; nrow = bilen[brow]; \
100       bcol = col/bs; \
101       ridx = row % bs; cidx = col % bs; \
102       low = 0; high = nrow; \
103       while (high-low > 3) { \
104         t = (low+high)/2; \
105         if (rp[t] > bcol) high = t; \
106         else              low  = t; \
107       } \
108       for (_i=low; _i<high; _i++) { \
109         if (rp[_i] > bcol) break; \
110         if (rp[_i] == bcol) { \
111           bap  = ap +  bs2*_i + bs*cidx + ridx; \
112           if (addv == ADD_VALUES) *bap += value;  \
113           else                    *bap  = value;  \
114           goto b_noinsert; \
115         } \
116       } \
117       if (b->nonew == 1) goto b_noinsert; \
118       if (b->nonew == -1) SETERRQ2(PETSC_ERR_ARG_OUTOFRANGE,"Inserting a new nonzero (%D, %D) into matrix", row, col); \
119       MatSeqXAIJReallocateAIJ(B,b->mbs,bs2,nrow,brow,bcol,rmax,ba,bi,bj,rp,ap,bimax,b->nonew,MatScalar); \
120       N = nrow++ - 1;  \
121       /* shift up all the later entries in this row */ \
122       for (ii=N; ii>=_i; ii--) { \
123         rp[ii+1] = rp[ii]; \
124         ierr = PetscMemcpy(ap+bs2*(ii+1),ap+bs2*(ii),bs2*sizeof(MatScalar));CHKERRQ(ierr); \
125       } \
126       if (N>=_i) { ierr = PetscMemzero(ap+bs2*_i,bs2*sizeof(MatScalar));CHKERRQ(ierr);}  \
127       rp[_i]                      = bcol;  \
128       ap[bs2*_i + bs*cidx + ridx] = value;  \
129       b_noinsert:; \
130     bilen[brow] = nrow; \
131 }
132 
133 /* Only add/insert a(i,j) with i<=j (blocks).
134    Any a(i,j) with i>j input by user is ingored.
135 */
136 #undef __FUNCT__
137 #define __FUNCT__ "MatSetValues_MPISBAIJ"
138 PetscErrorCode MatSetValues_MPISBAIJ(Mat mat,PetscInt m,const PetscInt im[],PetscInt n,const PetscInt in[],const PetscScalar v[],InsertMode addv)
139 {
140   Mat_MPISBAIJ   *baij = (Mat_MPISBAIJ*)mat->data;
141   MatScalar      value;
142   PetscTruth     roworiented = baij->roworiented;
143   PetscErrorCode ierr;
144   PetscInt       i,j,row,col;
145   PetscInt       rstart_orig=mat->rmap.rstart;
146   PetscInt       rend_orig=mat->rmap.rend,cstart_orig=mat->cmap.rstart;
147   PetscInt       cend_orig=mat->cmap.rend,bs=mat->rmap.bs;
148 
149   /* Some Variables required in the macro */
150   Mat            A = baij->A;
151   Mat_SeqSBAIJ   *a = (Mat_SeqSBAIJ*)(A)->data;
152   PetscInt       *aimax=a->imax,*ai=a->i,*ailen=a->ilen,*aj=a->j;
153   MatScalar      *aa=a->a;
154 
155   Mat            B = baij->B;
156   Mat_SeqBAIJ   *b = (Mat_SeqBAIJ*)(B)->data;
157   PetscInt      *bimax=b->imax,*bi=b->i,*bilen=b->ilen,*bj=b->j;
158   MatScalar     *ba=b->a;
159 
160   PetscInt      *rp,ii,nrow,_i,rmax,N,brow,bcol;
161   PetscInt      low,high,t,ridx,cidx,bs2=a->bs2;
162   MatScalar     *ap,*bap;
163 
164   /* for stash */
165   PetscInt      n_loc, *in_loc = PETSC_NULL;
166   MatScalar     *v_loc = PETSC_NULL;
167 
168   PetscFunctionBegin;
169 
170   if (!baij->donotstash){
171     if (n > baij->n_loc) {
172       ierr = PetscFree(baij->in_loc);CHKERRQ(ierr);
173       ierr = PetscFree(baij->v_loc);CHKERRQ(ierr);
174       ierr = PetscMalloc(n*sizeof(PetscInt),&baij->in_loc);CHKERRQ(ierr);
175       ierr = PetscMalloc(n*sizeof(MatScalar),&baij->v_loc);CHKERRQ(ierr);
176       baij->n_loc = n;
177     }
178     in_loc = baij->in_loc;
179     v_loc  = baij->v_loc;
180   }
181 
182   for (i=0; i<m; i++) {
183     if (im[i] < 0) continue;
184 #if defined(PETSC_USE_DEBUG)
185     if (im[i] >= mat->rmap.N) SETERRQ2(PETSC_ERR_ARG_OUTOFRANGE,"Row too large: row %D max %D",im[i],mat->rmap.N-1);
186 #endif
187     if (im[i] >= rstart_orig && im[i] < rend_orig) { /* this processor entry */
188       row = im[i] - rstart_orig;              /* local row index */
189       for (j=0; j<n; j++) {
190         if (im[i]/bs > in[j]/bs){
191           if (a->ignore_ltriangular){
192             continue;    /* ignore lower triangular blocks */
193           } else {
194             SETERRQ(PETSC_ERR_USER,"Lower triangular value cannot be set for sbaij format. Ignoring these values, run with -mat_ignore_lower_triangular or call MatSetOption(mat,MAT_IGNORE_LOWER_TRIANGULAR,PETSC_TRUE)");
195           }
196         }
197         if (in[j] >= cstart_orig && in[j] < cend_orig){  /* diag entry (A) */
198           col = in[j] - cstart_orig;          /* local col index */
199           brow = row/bs; bcol = col/bs;
200           if (brow > bcol) continue;  /* ignore lower triangular blocks of A */
201           if (roworiented) value = v[i*n+j]; else value = v[i+j*m];
202           MatSetValues_SeqSBAIJ_A_Private(row,col,value,addv);
203           /* ierr = MatSetValues_SeqBAIJ(baij->A,1,&row,1,&col,&value,addv);CHKERRQ(ierr); */
204         } else if (in[j] < 0) continue;
205 #if defined(PETSC_USE_DEBUG)
206         else if (in[j] >= mat->cmap.N) {SETERRQ2(PETSC_ERR_ARG_OUTOFRANGE,"Column too large: col %D max %D",in[j],mat->cmap.N-1);}
207 #endif
208         else {  /* off-diag entry (B) */
209           if (mat->was_assembled) {
210             if (!baij->colmap) {
211               ierr = CreateColmap_MPIBAIJ_Private(mat);CHKERRQ(ierr);
212             }
213 #if defined (PETSC_USE_CTABLE)
214             ierr = PetscTableFind(baij->colmap,in[j]/bs + 1,&col);CHKERRQ(ierr);
215             col  = col - 1;
216 #else
217             col = baij->colmap[in[j]/bs] - 1;
218 #endif
219             if (col < 0 && !((Mat_SeqSBAIJ*)(baij->A->data))->nonew) {
220               ierr = DisAssemble_MPISBAIJ(mat);CHKERRQ(ierr);
221               col =  in[j];
222               /* Reinitialize the variables required by MatSetValues_SeqBAIJ_B_Private() */
223               B = baij->B;
224               b = (Mat_SeqBAIJ*)(B)->data;
225               bimax=b->imax;bi=b->i;bilen=b->ilen;bj=b->j;
226               ba=b->a;
227             } else col += in[j]%bs;
228           } else col = in[j];
229           if (roworiented) value = v[i*n+j]; else value = v[i+j*m];
230           MatSetValues_SeqSBAIJ_B_Private(row,col,value,addv);
231           /* ierr = MatSetValues_SeqBAIJ(baij->B,1,&row,1,&col,&value,addv);CHKERRQ(ierr); */
232         }
233       }
234     } else {  /* off processor entry */
235       if (!baij->donotstash) {
236         n_loc = 0;
237         for (j=0; j<n; j++){
238           if (im[i]/bs > in[j]/bs) continue; /* ignore lower triangular blocks */
239           in_loc[n_loc] = in[j];
240           if (roworiented) {
241             v_loc[n_loc] = v[i*n+j];
242           } else {
243             v_loc[n_loc] = v[j*m+i];
244           }
245           n_loc++;
246         }
247         ierr = MatStashValuesRow_Private(&mat->stash,im[i],n_loc,in_loc,v_loc);CHKERRQ(ierr);
248       }
249     }
250   }
251   PetscFunctionReturn(0);
252 }
253 
254 #undef __FUNCT__
255 #define __FUNCT__ "MatSetValuesBlocked_MPISBAIJ"
256 PetscErrorCode MatSetValuesBlocked_MPISBAIJ(Mat mat,PetscInt m,const PetscInt im[],PetscInt n,const PetscInt in[],const MatScalar v[],InsertMode addv)
257 {
258   Mat_MPISBAIJ    *baij = (Mat_MPISBAIJ*)mat->data;
259   const MatScalar *value;
260   MatScalar       *barray=baij->barray;
261   PetscTruth      roworiented = baij->roworiented;
262   PetscErrorCode  ierr;
263   PetscInt        i,j,ii,jj,row,col,rstart=baij->rstartbs;
264   PetscInt        rend=baij->rendbs,cstart=baij->rstartbs,stepval;
265   PetscInt        cend=baij->rendbs,bs=mat->rmap.bs,bs2=baij->bs2;
266 
267   PetscFunctionBegin;
268   if(!barray) {
269     ierr         = PetscMalloc(bs2*sizeof(MatScalar),&barray);CHKERRQ(ierr);
270     baij->barray = barray;
271   }
272 
273   if (roworiented) {
274     stepval = (n-1)*bs;
275   } else {
276     stepval = (m-1)*bs;
277   }
278   for (i=0; i<m; i++) {
279     if (im[i] < 0) continue;
280 #if defined(PETSC_USE_DEBUG)
281     if (im[i] >= baij->Mbs) SETERRQ2(PETSC_ERR_ARG_OUTOFRANGE,"Row too large, row %D max %D",im[i],baij->Mbs-1);
282 #endif
283     if (im[i] >= rstart && im[i] < rend) {
284       row = im[i] - rstart;
285       for (j=0; j<n; j++) {
286         /* If NumCol = 1 then a copy is not required */
287         if ((roworiented) && (n == 1)) {
288           barray = (MatScalar*) v + i*bs2;
289         } else if((!roworiented) && (m == 1)) {
290           barray = (MatScalar*) v + j*bs2;
291         } else { /* Here a copy is required */
292           if (roworiented) {
293             value = v + i*(stepval+bs)*bs + j*bs;
294           } else {
295             value = v + j*(stepval+bs)*bs + i*bs;
296           }
297           for (ii=0; ii<bs; ii++,value+=stepval) {
298             for (jj=0; jj<bs; jj++) {
299               *barray++  = *value++;
300             }
301           }
302           barray -=bs2;
303         }
304 
305         if (in[j] >= cstart && in[j] < cend){
306           col  = in[j] - cstart;
307           ierr = MatSetValuesBlocked_SeqSBAIJ(baij->A,1,&row,1,&col,barray,addv);CHKERRQ(ierr);
308         }
309         else if (in[j] < 0) continue;
310 #if defined(PETSC_USE_DEBUG)
311         else if (in[j] >= baij->Nbs) {SETERRQ2(PETSC_ERR_ARG_OUTOFRANGE,"Column too large, col %D max %D",in[j],baij->Nbs-1);}
312 #endif
313         else {
314           if (mat->was_assembled) {
315             if (!baij->colmap) {
316               ierr = CreateColmap_MPIBAIJ_Private(mat);CHKERRQ(ierr);
317             }
318 
319 #if defined(PETSC_USE_DEBUG)
320 #if defined (PETSC_USE_CTABLE)
321             { PetscInt data;
322               ierr = PetscTableFind(baij->colmap,in[j]+1,&data);CHKERRQ(ierr);
323               if ((data - 1) % bs) SETERRQ(PETSC_ERR_PLIB,"Incorrect colmap");
324             }
325 #else
326             if ((baij->colmap[in[j]] - 1) % bs) SETERRQ(PETSC_ERR_PLIB,"Incorrect colmap");
327 #endif
328 #endif
329 #if defined (PETSC_USE_CTABLE)
330 	    ierr = PetscTableFind(baij->colmap,in[j]+1,&col);CHKERRQ(ierr);
331             col  = (col - 1)/bs;
332 #else
333             col = (baij->colmap[in[j]] - 1)/bs;
334 #endif
335             if (col < 0 && !((Mat_SeqBAIJ*)(baij->A->data))->nonew) {
336               ierr = DisAssemble_MPISBAIJ(mat);CHKERRQ(ierr);
337               col =  in[j];
338             }
339           }
340           else col = in[j];
341           ierr = MatSetValuesBlocked_SeqBAIJ(baij->B,1,&row,1,&col,barray,addv);CHKERRQ(ierr);
342         }
343       }
344     } else {
345       if (!baij->donotstash) {
346         if (roworiented) {
347           ierr = MatStashValuesRowBlocked_Private(&mat->bstash,im[i],n,in,v,m,n,i);CHKERRQ(ierr);
348         } else {
349           ierr = MatStashValuesColBlocked_Private(&mat->bstash,im[i],n,in,v,m,n,i);CHKERRQ(ierr);
350         }
351       }
352     }
353   }
354   PetscFunctionReturn(0);
355 }
356 
357 #undef __FUNCT__
358 #define __FUNCT__ "MatGetValues_MPISBAIJ"
359 PetscErrorCode MatGetValues_MPISBAIJ(Mat mat,PetscInt m,const PetscInt idxm[],PetscInt n,const PetscInt idxn[],PetscScalar v[])
360 {
361   Mat_MPISBAIJ   *baij = (Mat_MPISBAIJ*)mat->data;
362   PetscErrorCode ierr;
363   PetscInt       bs=mat->rmap.bs,i,j,bsrstart = mat->rmap.rstart,bsrend = mat->rmap.rend;
364   PetscInt       bscstart = mat->cmap.rstart,bscend = mat->cmap.rend,row,col,data;
365 
366   PetscFunctionBegin;
367   for (i=0; i<m; i++) {
368     if (idxm[i] < 0) continue; /* SETERRQ1(PETSC_ERR_ARG_OUTOFRANGE,"Negative row: %D",idxm[i]); */
369     if (idxm[i] >= mat->rmap.N) SETERRQ2(PETSC_ERR_ARG_OUTOFRANGE,"Row too large: row %D max %D",idxm[i],mat->rmap.N-1);
370     if (idxm[i] >= bsrstart && idxm[i] < bsrend) {
371       row = idxm[i] - bsrstart;
372       for (j=0; j<n; j++) {
373         if (idxn[j] < 0) continue; /* SETERRQ1(PETSC_ERR_ARG_OUTOFRANGE,"Negative column %D",idxn[j]); */
374         if (idxn[j] >= mat->cmap.N) SETERRQ2(PETSC_ERR_ARG_OUTOFRANGE,"Column too large: col %D max %D",idxn[j],mat->cmap.N-1);
375         if (idxn[j] >= bscstart && idxn[j] < bscend){
376           col = idxn[j] - bscstart;
377           ierr = MatGetValues_SeqSBAIJ(baij->A,1,&row,1,&col,v+i*n+j);CHKERRQ(ierr);
378         } else {
379           if (!baij->colmap) {
380             ierr = CreateColmap_MPIBAIJ_Private(mat);CHKERRQ(ierr);
381           }
382 #if defined (PETSC_USE_CTABLE)
383           ierr = PetscTableFind(baij->colmap,idxn[j]/bs+1,&data);CHKERRQ(ierr);
384           data --;
385 #else
386           data = baij->colmap[idxn[j]/bs]-1;
387 #endif
388           if((data < 0) || (baij->garray[data/bs] != idxn[j]/bs)) *(v+i*n+j) = 0.0;
389           else {
390             col  = data + idxn[j]%bs;
391             ierr = MatGetValues_SeqBAIJ(baij->B,1,&row,1,&col,v+i*n+j);CHKERRQ(ierr);
392           }
393         }
394       }
395     } else {
396       SETERRQ(PETSC_ERR_SUP,"Only local values currently supported");
397     }
398   }
399  PetscFunctionReturn(0);
400 }
401 
402 #undef __FUNCT__
403 #define __FUNCT__ "MatNorm_MPISBAIJ"
404 PetscErrorCode MatNorm_MPISBAIJ(Mat mat,NormType type,PetscReal *norm)
405 {
406   Mat_MPISBAIJ   *baij = (Mat_MPISBAIJ*)mat->data;
407   PetscErrorCode ierr;
408   PetscReal      sum[2],*lnorm2;
409 
410   PetscFunctionBegin;
411   if (baij->size == 1) {
412     ierr =  MatNorm(baij->A,type,norm);CHKERRQ(ierr);
413   } else {
414     if (type == NORM_FROBENIUS) {
415       ierr = PetscMalloc(2*sizeof(PetscReal),&lnorm2);CHKERRQ(ierr);
416       ierr =  MatNorm(baij->A,type,lnorm2);CHKERRQ(ierr);
417       *lnorm2 = (*lnorm2)*(*lnorm2); lnorm2++;            /* squar power of norm(A) */
418       ierr =  MatNorm(baij->B,type,lnorm2);CHKERRQ(ierr);
419       *lnorm2 = (*lnorm2)*(*lnorm2); lnorm2--;             /* squar power of norm(B) */
420       ierr = MPI_Allreduce(lnorm2,&sum,2,MPIU_REAL,MPI_SUM,((PetscObject)mat)->comm);CHKERRQ(ierr);
421       *norm = sqrt(sum[0] + 2*sum[1]);
422       ierr = PetscFree(lnorm2);CHKERRQ(ierr);
423     } else if (type == NORM_INFINITY || type == NORM_1) { /* max row/column sum */
424       Mat_SeqSBAIJ *amat=(Mat_SeqSBAIJ*)baij->A->data;
425       Mat_SeqBAIJ  *bmat=(Mat_SeqBAIJ*)baij->B->data;
426       PetscReal    *rsum,*rsum2,vabs;
427       PetscInt     *jj,*garray=baij->garray,rstart=baij->rstartbs,nz;
428       PetscInt     brow,bcol,col,bs=baij->A->rmap.bs,row,grow,gcol,mbs=amat->mbs;
429       MatScalar    *v;
430 
431       ierr  = PetscMalloc((2*mat->cmap.N+1)*sizeof(PetscReal),&rsum);CHKERRQ(ierr);
432       rsum2 = rsum + mat->cmap.N;
433       ierr  = PetscMemzero(rsum,mat->cmap.N*sizeof(PetscReal));CHKERRQ(ierr);
434       /* Amat */
435       v = amat->a; jj = amat->j;
436       for (brow=0; brow<mbs; brow++) {
437         grow = bs*(rstart + brow);
438         nz = amat->i[brow+1] - amat->i[brow];
439         for (bcol=0; bcol<nz; bcol++){
440           gcol = bs*(rstart + *jj); jj++;
441           for (col=0; col<bs; col++){
442             for (row=0; row<bs; row++){
443               vabs = PetscAbsScalar(*v); v++;
444               rsum[gcol+col] += vabs;
445               /* non-diagonal block */
446               if (bcol > 0 && vabs > 0.0) rsum[grow+row] += vabs;
447             }
448           }
449         }
450       }
451       /* Bmat */
452       v = bmat->a; jj = bmat->j;
453       for (brow=0; brow<mbs; brow++) {
454         grow = bs*(rstart + brow);
455         nz = bmat->i[brow+1] - bmat->i[brow];
456         for (bcol=0; bcol<nz; bcol++){
457           gcol = bs*garray[*jj]; jj++;
458           for (col=0; col<bs; col++){
459             for (row=0; row<bs; row++){
460               vabs = PetscAbsScalar(*v); v++;
461               rsum[gcol+col] += vabs;
462               rsum[grow+row] += vabs;
463             }
464           }
465         }
466       }
467       ierr = MPI_Allreduce(rsum,rsum2,mat->cmap.N,MPIU_REAL,MPI_SUM,((PetscObject)mat)->comm);CHKERRQ(ierr);
468       *norm = 0.0;
469       for (col=0; col<mat->cmap.N; col++) {
470         if (rsum2[col] > *norm) *norm = rsum2[col];
471       }
472       ierr = PetscFree(rsum);CHKERRQ(ierr);
473     } else {
474       SETERRQ(PETSC_ERR_SUP,"No support for this norm yet");
475     }
476   }
477   PetscFunctionReturn(0);
478 }
479 
480 #undef __FUNCT__
481 #define __FUNCT__ "MatAssemblyBegin_MPISBAIJ"
482 PetscErrorCode MatAssemblyBegin_MPISBAIJ(Mat mat,MatAssemblyType mode)
483 {
484   Mat_MPISBAIJ   *baij = (Mat_MPISBAIJ*)mat->data;
485   PetscErrorCode ierr;
486   PetscInt       nstash,reallocs;
487   InsertMode     addv;
488 
489   PetscFunctionBegin;
490   if (baij->donotstash) {
491     PetscFunctionReturn(0);
492   }
493 
494   /* make sure all processors are either in INSERTMODE or ADDMODE */
495   ierr = MPI_Allreduce(&mat->insertmode,&addv,1,MPI_INT,MPI_BOR,((PetscObject)mat)->comm);CHKERRQ(ierr);
496   if (addv == (ADD_VALUES|INSERT_VALUES)) {
497     SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Some processors inserted others added");
498   }
499   mat->insertmode = addv; /* in case this processor had no cache */
500 
501   ierr = MatStashScatterBegin_Private(mat,&mat->stash,mat->rmap.range);CHKERRQ(ierr);
502   ierr = MatStashScatterBegin_Private(mat,&mat->bstash,baij->rangebs);CHKERRQ(ierr);
503   ierr = MatStashGetInfo_Private(&mat->stash,&nstash,&reallocs);CHKERRQ(ierr);
504   ierr = PetscInfo2(mat,"Stash has %D entries,uses %D mallocs.\n",nstash,reallocs);CHKERRQ(ierr);
505   ierr = MatStashGetInfo_Private(&mat->stash,&nstash,&reallocs);CHKERRQ(ierr);
506   ierr = PetscInfo2(mat,"Block-Stash has %D entries, uses %D mallocs.\n",nstash,reallocs);CHKERRQ(ierr);
507   PetscFunctionReturn(0);
508 }
509 
510 #undef __FUNCT__
511 #define __FUNCT__ "MatAssemblyEnd_MPISBAIJ"
512 PetscErrorCode MatAssemblyEnd_MPISBAIJ(Mat mat,MatAssemblyType mode)
513 {
514   Mat_MPISBAIJ   *baij=(Mat_MPISBAIJ*)mat->data;
515   Mat_SeqSBAIJ   *a=(Mat_SeqSBAIJ*)baij->A->data;
516   PetscErrorCode ierr;
517   PetscInt       i,j,rstart,ncols,flg,bs2=baij->bs2;
518   PetscInt       *row,*col;
519   PetscTruth     other_disassembled;
520   PetscMPIInt    n;
521   PetscTruth     r1,r2,r3;
522   MatScalar      *val;
523   InsertMode     addv = mat->insertmode;
524 
525   /* do not use 'b=(Mat_SeqBAIJ*)baij->B->data' as B can be reset in disassembly */
526   PetscFunctionBegin;
527 
528   if (!baij->donotstash) {
529     while (1) {
530       ierr = MatStashScatterGetMesg_Private(&mat->stash,&n,&row,&col,&val,&flg);CHKERRQ(ierr);
531       if (!flg) break;
532 
533       for (i=0; i<n;) {
534         /* Now identify the consecutive vals belonging to the same row */
535         for (j=i,rstart=row[j]; j<n; j++) { if (row[j] != rstart) break; }
536         if (j < n) ncols = j-i;
537         else       ncols = n-i;
538         /* Now assemble all these values with a single function call */
539         ierr = MatSetValues_MPISBAIJ(mat,1,row+i,ncols,col+i,val+i,addv);CHKERRQ(ierr);
540         i = j;
541       }
542     }
543     ierr = MatStashScatterEnd_Private(&mat->stash);CHKERRQ(ierr);
544     /* Now process the block-stash. Since the values are stashed column-oriented,
545        set the roworiented flag to column oriented, and after MatSetValues()
546        restore the original flags */
547     r1 = baij->roworiented;
548     r2 = a->roworiented;
549     r3 = ((Mat_SeqBAIJ*)baij->B->data)->roworiented;
550     baij->roworiented = PETSC_FALSE;
551     a->roworiented    = PETSC_FALSE;
552     ((Mat_SeqBAIJ*)baij->B->data)->roworiented    = PETSC_FALSE; /* b->roworinted */
553     while (1) {
554       ierr = MatStashScatterGetMesg_Private(&mat->bstash,&n,&row,&col,&val,&flg);CHKERRQ(ierr);
555       if (!flg) break;
556 
557       for (i=0; i<n;) {
558         /* Now identify the consecutive vals belonging to the same row */
559         for (j=i,rstart=row[j]; j<n; j++) { if (row[j] != rstart) break; }
560         if (j < n) ncols = j-i;
561         else       ncols = n-i;
562         ierr = MatSetValuesBlocked_MPISBAIJ(mat,1,row+i,ncols,col+i,val+i*bs2,addv);CHKERRQ(ierr);
563         i = j;
564       }
565     }
566     ierr = MatStashScatterEnd_Private(&mat->bstash);CHKERRQ(ierr);
567     baij->roworiented = r1;
568     a->roworiented    = r2;
569     ((Mat_SeqBAIJ*)baij->B->data)->roworiented    = r3; /* b->roworinted */
570   }
571 
572   ierr = MatAssemblyBegin(baij->A,mode);CHKERRQ(ierr);
573   ierr = MatAssemblyEnd(baij->A,mode);CHKERRQ(ierr);
574 
575   /* determine if any processor has disassembled, if so we must
576      also disassemble ourselfs, in order that we may reassemble. */
577   /*
578      if nonzero structure of submatrix B cannot change then we know that
579      no processor disassembled thus we can skip this stuff
580   */
581   if (!((Mat_SeqBAIJ*)baij->B->data)->nonew)  {
582     ierr = MPI_Allreduce(&mat->was_assembled,&other_disassembled,1,MPI_INT,MPI_PROD,((PetscObject)mat)->comm);CHKERRQ(ierr);
583     if (mat->was_assembled && !other_disassembled) {
584       ierr = DisAssemble_MPISBAIJ(mat);CHKERRQ(ierr);
585     }
586   }
587 
588   if (!mat->was_assembled && mode == MAT_FINAL_ASSEMBLY) {
589     ierr = MatSetUpMultiply_MPISBAIJ(mat);CHKERRQ(ierr); /* setup Mvctx and sMvctx */
590   }
591   ((Mat_SeqBAIJ*)baij->B->data)->compressedrow.use = PETSC_TRUE; /* b->compressedrow.use */
592   ierr = MatAssemblyBegin(baij->B,mode);CHKERRQ(ierr);
593   ierr = MatAssemblyEnd(baij->B,mode);CHKERRQ(ierr);
594 
595   ierr = PetscFree(baij->rowvalues);CHKERRQ(ierr);
596   baij->rowvalues = 0;
597 
598   PetscFunctionReturn(0);
599 }
600 
601 extern PetscErrorCode MatSetValues_MPIBAIJ(Mat,PetscInt,const PetscInt[],PetscInt,const PetscInt[],const PetscScalar[],InsertMode);
602 #undef __FUNCT__
603 #define __FUNCT__ "MatView_MPISBAIJ_ASCIIorDraworSocket"
604 static PetscErrorCode MatView_MPISBAIJ_ASCIIorDraworSocket(Mat mat,PetscViewer viewer)
605 {
606   Mat_MPISBAIJ      *baij = (Mat_MPISBAIJ*)mat->data;
607   PetscErrorCode    ierr;
608   PetscInt          bs = mat->rmap.bs;
609   PetscMPIInt       size = baij->size,rank = baij->rank;
610   PetscTruth        iascii,isdraw;
611   PetscViewer       sviewer;
612   PetscViewerFormat format;
613 
614   PetscFunctionBegin;
615   ierr = PetscTypeCompare((PetscObject)viewer,PETSC_VIEWER_ASCII,&iascii);CHKERRQ(ierr);
616   ierr = PetscTypeCompare((PetscObject)viewer,PETSC_VIEWER_DRAW,&isdraw);CHKERRQ(ierr);
617   if (iascii) {
618     ierr = PetscViewerGetFormat(viewer,&format);CHKERRQ(ierr);
619     if (format == PETSC_VIEWER_ASCII_INFO_DETAIL) {
620       MatInfo info;
621       ierr = MPI_Comm_rank(((PetscObject)mat)->comm,&rank);CHKERRQ(ierr);
622       ierr = MatGetInfo(mat,MAT_LOCAL,&info);CHKERRQ(ierr);
623       ierr = PetscViewerASCIISynchronizedPrintf(viewer,"[%d] Local rows %D nz %D nz alloced %D bs %D mem %D\n",
624               rank,mat->rmap.N,(PetscInt)info.nz_used*bs,(PetscInt)info.nz_allocated*bs,
625               mat->rmap.bs,(PetscInt)info.memory);CHKERRQ(ierr);
626       ierr = MatGetInfo(baij->A,MAT_LOCAL,&info);CHKERRQ(ierr);
627       ierr = PetscViewerASCIISynchronizedPrintf(viewer,"[%d] on-diagonal part: nz %D \n",rank,(PetscInt)info.nz_used*bs);CHKERRQ(ierr);
628       ierr = MatGetInfo(baij->B,MAT_LOCAL,&info);CHKERRQ(ierr);
629       ierr = PetscViewerASCIISynchronizedPrintf(viewer,"[%d] off-diagonal part: nz %D \n",rank,(PetscInt)info.nz_used*bs);CHKERRQ(ierr);
630       ierr = PetscViewerFlush(viewer);CHKERRQ(ierr);
631       ierr = PetscViewerASCIIPrintf(viewer,"Information on VecScatter used in matrix-vector product: \n");CHKERRQ(ierr);
632       ierr = VecScatterView(baij->Mvctx,viewer);CHKERRQ(ierr);
633       PetscFunctionReturn(0);
634     } else if (format == PETSC_VIEWER_ASCII_INFO) {
635       ierr = PetscViewerASCIIPrintf(viewer,"  block size is %D\n",bs);CHKERRQ(ierr);
636       PetscFunctionReturn(0);
637     } else if (format == PETSC_VIEWER_ASCII_FACTOR_INFO) {
638       PetscFunctionReturn(0);
639     }
640   }
641 
642   if (isdraw) {
643     PetscDraw  draw;
644     PetscTruth isnull;
645     ierr = PetscViewerDrawGetDraw(viewer,0,&draw);CHKERRQ(ierr);
646     ierr = PetscDrawIsNull(draw,&isnull);CHKERRQ(ierr); if (isnull) PetscFunctionReturn(0);
647   }
648 
649   if (size == 1) {
650     ierr = PetscObjectSetName((PetscObject)baij->A,((PetscObject)mat)->name);CHKERRQ(ierr);
651     ierr = MatView(baij->A,viewer);CHKERRQ(ierr);
652   } else {
653     /* assemble the entire matrix onto first processor. */
654     Mat          A;
655     Mat_SeqSBAIJ *Aloc;
656     Mat_SeqBAIJ  *Bloc;
657     PetscInt     M = mat->rmap.N,N = mat->cmap.N,*ai,*aj,col,i,j,k,*rvals,mbs = baij->mbs;
658     MatScalar    *a;
659 
660     /* Should this be the same type as mat? */
661     ierr = MatCreate(((PetscObject)mat)->comm,&A);CHKERRQ(ierr);
662     if (!rank) {
663       ierr = MatSetSizes(A,M,N,M,N);CHKERRQ(ierr);
664     } else {
665       ierr = MatSetSizes(A,0,0,M,N);CHKERRQ(ierr);
666     }
667     ierr = MatSetType(A,MATMPISBAIJ);CHKERRQ(ierr);
668     ierr = MatMPISBAIJSetPreallocation(A,mat->rmap.bs,0,PETSC_NULL,0,PETSC_NULL);CHKERRQ(ierr);
669     ierr = PetscLogObjectParent(mat,A);CHKERRQ(ierr);
670 
671     /* copy over the A part */
672     Aloc  = (Mat_SeqSBAIJ*)baij->A->data;
673     ai    = Aloc->i; aj = Aloc->j; a = Aloc->a;
674     ierr  = PetscMalloc(bs*sizeof(PetscInt),&rvals);CHKERRQ(ierr);
675 
676     for (i=0; i<mbs; i++) {
677       rvals[0] = bs*(baij->rstartbs + i);
678       for (j=1; j<bs; j++) { rvals[j] = rvals[j-1] + 1; }
679       for (j=ai[i]; j<ai[i+1]; j++) {
680         col = (baij->cstartbs+aj[j])*bs;
681         for (k=0; k<bs; k++) {
682           ierr = MatSetValues_MPISBAIJ(A,bs,rvals,1,&col,a,INSERT_VALUES);CHKERRQ(ierr);
683           col++; a += bs;
684         }
685       }
686     }
687     /* copy over the B part */
688     Bloc = (Mat_SeqBAIJ*)baij->B->data;
689     ai = Bloc->i; aj = Bloc->j; a = Bloc->a;
690     for (i=0; i<mbs; i++) {
691 
692       rvals[0] = bs*(baij->rstartbs + i);
693       for (j=1; j<bs; j++) { rvals[j] = rvals[j-1] + 1; }
694       for (j=ai[i]; j<ai[i+1]; j++) {
695         col = baij->garray[aj[j]]*bs;
696         for (k=0; k<bs; k++) {
697           ierr = MatSetValues_MPIBAIJ(A,bs,rvals,1,&col,a,INSERT_VALUES);CHKERRQ(ierr);
698           col++; a += bs;
699         }
700       }
701     }
702     ierr = PetscFree(rvals);CHKERRQ(ierr);
703     ierr = MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
704     ierr = MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
705     /*
706        Everyone has to call to draw the matrix since the graphics waits are
707        synchronized across all processors that share the PetscDraw object
708     */
709     ierr = PetscViewerGetSingleton(viewer,&sviewer);CHKERRQ(ierr);
710     if (!rank) {
711       ierr = PetscObjectSetName((PetscObject)((Mat_MPISBAIJ*)(A->data))->A,((PetscObject)mat)->name);CHKERRQ(ierr);
712       ierr = MatView(((Mat_MPISBAIJ*)(A->data))->A,sviewer);CHKERRQ(ierr);
713     }
714     ierr = PetscViewerRestoreSingleton(viewer,&sviewer);CHKERRQ(ierr);
715     ierr = MatDestroy(A);CHKERRQ(ierr);
716   }
717   PetscFunctionReturn(0);
718 }
719 
720 #undef __FUNCT__
721 #define __FUNCT__ "MatView_MPISBAIJ"
722 PetscErrorCode MatView_MPISBAIJ(Mat mat,PetscViewer viewer)
723 {
724   PetscErrorCode ierr;
725   PetscTruth     iascii,isdraw,issocket,isbinary;
726 
727   PetscFunctionBegin;
728   ierr = PetscTypeCompare((PetscObject)viewer,PETSC_VIEWER_ASCII,&iascii);CHKERRQ(ierr);
729   ierr = PetscTypeCompare((PetscObject)viewer,PETSC_VIEWER_DRAW,&isdraw);CHKERRQ(ierr);
730   ierr = PetscTypeCompare((PetscObject)viewer,PETSC_VIEWER_SOCKET,&issocket);CHKERRQ(ierr);
731   ierr = PetscTypeCompare((PetscObject)viewer,PETSC_VIEWER_BINARY,&isbinary);CHKERRQ(ierr);
732   if (iascii || isdraw || issocket || isbinary) {
733     ierr = MatView_MPISBAIJ_ASCIIorDraworSocket(mat,viewer);CHKERRQ(ierr);
734   } else {
735     SETERRQ1(PETSC_ERR_SUP,"Viewer type %s not supported by MPISBAIJ matrices",((PetscObject)viewer)->type_name);
736   }
737   PetscFunctionReturn(0);
738 }
739 
740 #undef __FUNCT__
741 #define __FUNCT__ "MatDestroy_MPISBAIJ"
742 PetscErrorCode MatDestroy_MPISBAIJ(Mat mat)
743 {
744   Mat_MPISBAIJ   *baij = (Mat_MPISBAIJ*)mat->data;
745   PetscErrorCode ierr;
746 
747   PetscFunctionBegin;
748 #if defined(PETSC_USE_LOG)
749   PetscLogObjectState((PetscObject)mat,"Rows=%D,Cols=%D",mat->rmap.N,mat->cmap.N);
750 #endif
751   ierr = MatStashDestroy_Private(&mat->stash);CHKERRQ(ierr);
752   ierr = MatStashDestroy_Private(&mat->bstash);CHKERRQ(ierr);
753   ierr = MatDestroy(baij->A);CHKERRQ(ierr);
754   ierr = MatDestroy(baij->B);CHKERRQ(ierr);
755 #if defined (PETSC_USE_CTABLE)
756   if (baij->colmap) {ierr = PetscTableDestroy(baij->colmap);CHKERRQ(ierr);}
757 #else
758   ierr = PetscFree(baij->colmap);CHKERRQ(ierr);
759 #endif
760   ierr = PetscFree(baij->garray);CHKERRQ(ierr);
761   if (baij->lvec)   {ierr = VecDestroy(baij->lvec);CHKERRQ(ierr);}
762   if (baij->Mvctx)  {ierr = VecScatterDestroy(baij->Mvctx);CHKERRQ(ierr);}
763   if (baij->slvec0) {
764     ierr = VecDestroy(baij->slvec0);CHKERRQ(ierr);
765     ierr = VecDestroy(baij->slvec0b);CHKERRQ(ierr);
766   }
767   if (baij->slvec1) {
768     ierr = VecDestroy(baij->slvec1);CHKERRQ(ierr);
769     ierr = VecDestroy(baij->slvec1a);CHKERRQ(ierr);
770     ierr = VecDestroy(baij->slvec1b);CHKERRQ(ierr);
771   }
772   if (baij->sMvctx)  {ierr = VecScatterDestroy(baij->sMvctx);CHKERRQ(ierr);}
773   ierr = PetscFree(baij->rowvalues);CHKERRQ(ierr);
774   ierr = PetscFree(baij->barray);CHKERRQ(ierr);
775   ierr = PetscFree(baij->hd);CHKERRQ(ierr);
776 #if defined(PETSC_USE_MAT_SINGLE)
777   ierr = PetscFree(baij->setvaluescopy);CHKERRQ(ierr);
778 #endif
779   ierr = PetscFree(baij->in_loc);CHKERRQ(ierr);
780   ierr = PetscFree(baij->v_loc);CHKERRQ(ierr);
781   ierr = PetscFree(baij->rangebs);CHKERRQ(ierr);
782   ierr = PetscFree(baij);CHKERRQ(ierr);
783 
784   ierr = PetscObjectChangeTypeName((PetscObject)mat,0);CHKERRQ(ierr);
785   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatStoreValues_C","",PETSC_NULL);CHKERRQ(ierr);
786   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatRetrieveValues_C","",PETSC_NULL);CHKERRQ(ierr);
787   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatGetDiagonalBlock_C","",PETSC_NULL);CHKERRQ(ierr);
788   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatMPISBAIJSetPreallocation_C","",PETSC_NULL);CHKERRQ(ierr);
789   PetscFunctionReturn(0);
790 }
791 
792 #undef __FUNCT__
793 #define __FUNCT__ "MatMult_MPISBAIJ"
794 PetscErrorCode MatMult_MPISBAIJ(Mat A,Vec xx,Vec yy)
795 {
796   Mat_MPISBAIJ   *a = (Mat_MPISBAIJ*)A->data;
797   PetscErrorCode ierr;
798   PetscInt       nt,mbs=a->mbs,bs=A->rmap.bs;
799   PetscScalar    *x,*from,zero=0.0;
800 
801   PetscFunctionBegin;
802   ierr = VecGetLocalSize(xx,&nt);CHKERRQ(ierr);
803   if (nt != A->cmap.n) {
804     SETERRQ(PETSC_ERR_ARG_SIZ,"Incompatible partition of A and xx");
805   }
806 
807   /* diagonal part */
808   ierr = (*a->A->ops->mult)(a->A,xx,a->slvec1a);CHKERRQ(ierr);
809   ierr = VecSet(a->slvec1b,zero);CHKERRQ(ierr);
810 
811   /* subdiagonal part */
812   ierr = (*a->B->ops->multtranspose)(a->B,xx,a->slvec0b);CHKERRQ(ierr);
813 
814   /* copy x into the vec slvec0 */
815   ierr = VecGetArray(a->slvec0,&from);CHKERRQ(ierr);
816   ierr = VecGetArray(xx,&x);CHKERRQ(ierr);
817 
818   ierr = PetscMemcpy(from,x,bs*mbs*sizeof(MatScalar));CHKERRQ(ierr);
819   ierr = VecRestoreArray(a->slvec0,&from);CHKERRQ(ierr);
820   ierr = VecRestoreArray(xx,&x);CHKERRQ(ierr);
821 
822   ierr = VecScatterBegin(a->sMvctx,a->slvec0,a->slvec1,ADD_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
823   ierr = VecScatterEnd(a->sMvctx,a->slvec0,a->slvec1,ADD_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
824   /* supperdiagonal part */
825   ierr = (*a->B->ops->multadd)(a->B,a->slvec1b,a->slvec1a,yy);CHKERRQ(ierr);
826   PetscFunctionReturn(0);
827 }
828 
829 #undef __FUNCT__
830 #define __FUNCT__ "MatMult_MPISBAIJ_2comm"
831 PetscErrorCode MatMult_MPISBAIJ_2comm(Mat A,Vec xx,Vec yy)
832 {
833   Mat_MPISBAIJ   *a = (Mat_MPISBAIJ*)A->data;
834   PetscErrorCode ierr;
835   PetscInt       nt;
836 
837   PetscFunctionBegin;
838   ierr = VecGetLocalSize(xx,&nt);CHKERRQ(ierr);
839   if (nt != A->cmap.n) {
840     SETERRQ(PETSC_ERR_ARG_SIZ,"Incompatible partition of A and xx");
841   }
842   ierr = VecGetLocalSize(yy,&nt);CHKERRQ(ierr);
843   if (nt != A->rmap.N) {
844     SETERRQ(PETSC_ERR_ARG_SIZ,"Incompatible parition of A and yy");
845   }
846 
847   ierr = VecScatterBegin(a->Mvctx,xx,a->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
848   /* do diagonal part */
849   ierr = (*a->A->ops->mult)(a->A,xx,yy);CHKERRQ(ierr);
850   /* do supperdiagonal part */
851   ierr = VecScatterEnd(a->Mvctx,xx,a->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
852   ierr = (*a->B->ops->multadd)(a->B,a->lvec,yy,yy);CHKERRQ(ierr);
853   /* do subdiagonal part */
854   ierr = (*a->B->ops->multtranspose)(a->B,xx,a->lvec);CHKERRQ(ierr);
855   ierr = VecScatterBegin(a->Mvctx,a->lvec,yy,ADD_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
856   ierr = VecScatterEnd(a->Mvctx,a->lvec,yy,ADD_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
857 
858   PetscFunctionReturn(0);
859 }
860 
861 #undef __FUNCT__
862 #define __FUNCT__ "MatMultAdd_MPISBAIJ"
863 PetscErrorCode MatMultAdd_MPISBAIJ(Mat A,Vec xx,Vec yy,Vec zz)
864 {
865   Mat_MPISBAIJ   *a = (Mat_MPISBAIJ*)A->data;
866   PetscErrorCode ierr;
867   PetscInt       mbs=a->mbs,bs=A->rmap.bs;
868   PetscScalar    *x,*from,zero=0.0;
869 
870   PetscFunctionBegin;
871   /*
872   PetscSynchronizedPrintf(((PetscObject)A)->comm," MatMultAdd is called ...\n");
873   PetscSynchronizedFlush(((PetscObject)A)->comm);
874   */
875   /* diagonal part */
876   ierr = (*a->A->ops->multadd)(a->A,xx,yy,a->slvec1a);CHKERRQ(ierr);
877   ierr = VecSet(a->slvec1b,zero);CHKERRQ(ierr);
878 
879   /* subdiagonal part */
880   ierr = (*a->B->ops->multtranspose)(a->B,xx,a->slvec0b);CHKERRQ(ierr);
881 
882   /* copy x into the vec slvec0 */
883   ierr = VecGetArray(a->slvec0,&from);CHKERRQ(ierr);
884   ierr = VecGetArray(xx,&x);CHKERRQ(ierr);
885   ierr = PetscMemcpy(from,x,bs*mbs*sizeof(MatScalar));CHKERRQ(ierr);
886   ierr = VecRestoreArray(a->slvec0,&from);CHKERRQ(ierr);
887 
888   ierr = VecScatterBegin(a->sMvctx,a->slvec0,a->slvec1,ADD_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
889   ierr = VecRestoreArray(xx,&x);CHKERRQ(ierr);
890   ierr = VecScatterEnd(a->sMvctx,a->slvec0,a->slvec1,ADD_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
891 
892   /* supperdiagonal part */
893   ierr = (*a->B->ops->multadd)(a->B,a->slvec1b,a->slvec1a,zz);CHKERRQ(ierr);
894 
895   PetscFunctionReturn(0);
896 }
897 
898 #undef __FUNCT__
899 #define __FUNCT__ "MatMultAdd_MPISBAIJ_2comm"
900 PetscErrorCode MatMultAdd_MPISBAIJ_2comm(Mat A,Vec xx,Vec yy,Vec zz)
901 {
902   Mat_MPISBAIJ   *a = (Mat_MPISBAIJ*)A->data;
903   PetscErrorCode ierr;
904 
905   PetscFunctionBegin;
906   ierr = VecScatterBegin(a->Mvctx,xx,a->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
907   /* do diagonal part */
908   ierr = (*a->A->ops->multadd)(a->A,xx,yy,zz);CHKERRQ(ierr);
909   /* do supperdiagonal part */
910   ierr = VecScatterEnd(a->Mvctx,xx,a->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
911   ierr = (*a->B->ops->multadd)(a->B,a->lvec,zz,zz);CHKERRQ(ierr);
912 
913   /* do subdiagonal part */
914   ierr = (*a->B->ops->multtranspose)(a->B,xx,a->lvec);CHKERRQ(ierr);
915   ierr = VecScatterBegin(a->Mvctx,a->lvec,zz,ADD_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
916   ierr = VecScatterEnd(a->Mvctx,a->lvec,zz,ADD_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
917 
918   PetscFunctionReturn(0);
919 }
920 
921 /*
922   This only works correctly for square matrices where the subblock A->A is the
923    diagonal block
924 */
925 #undef __FUNCT__
926 #define __FUNCT__ "MatGetDiagonal_MPISBAIJ"
927 PetscErrorCode MatGetDiagonal_MPISBAIJ(Mat A,Vec v)
928 {
929   Mat_MPISBAIJ   *a = (Mat_MPISBAIJ*)A->data;
930   PetscErrorCode ierr;
931 
932   PetscFunctionBegin;
933   /* if (a->rmap.N != a->cmap.N) SETERRQ(PETSC_ERR_SUP,"Supports only square matrix where A->A is diag block"); */
934   ierr = MatGetDiagonal(a->A,v);CHKERRQ(ierr);
935   PetscFunctionReturn(0);
936 }
937 
938 #undef __FUNCT__
939 #define __FUNCT__ "MatScale_MPISBAIJ"
940 PetscErrorCode MatScale_MPISBAIJ(Mat A,PetscScalar aa)
941 {
942   Mat_MPISBAIJ   *a = (Mat_MPISBAIJ*)A->data;
943   PetscErrorCode ierr;
944 
945   PetscFunctionBegin;
946   ierr = MatScale(a->A,aa);CHKERRQ(ierr);
947   ierr = MatScale(a->B,aa);CHKERRQ(ierr);
948   PetscFunctionReturn(0);
949 }
950 
951 #undef __FUNCT__
952 #define __FUNCT__ "MatGetRow_MPISBAIJ"
953 PetscErrorCode MatGetRow_MPISBAIJ(Mat matin,PetscInt row,PetscInt *nz,PetscInt **idx,PetscScalar **v)
954 {
955   Mat_MPISBAIJ   *mat = (Mat_MPISBAIJ*)matin->data;
956   PetscScalar    *vworkA,*vworkB,**pvA,**pvB,*v_p;
957   PetscErrorCode ierr;
958   PetscInt       bs = matin->rmap.bs,bs2 = mat->bs2,i,*cworkA,*cworkB,**pcA,**pcB;
959   PetscInt       nztot,nzA,nzB,lrow,brstart = matin->rmap.rstart,brend = matin->rmap.rend;
960   PetscInt       *cmap,*idx_p,cstart = mat->rstartbs;
961 
962   PetscFunctionBegin;
963   if (mat->getrowactive == PETSC_TRUE) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Already active");
964   mat->getrowactive = PETSC_TRUE;
965 
966   if (!mat->rowvalues && (idx || v)) {
967     /*
968         allocate enough space to hold information from the longest row.
969     */
970     Mat_SeqSBAIJ *Aa = (Mat_SeqSBAIJ*)mat->A->data;
971     Mat_SeqBAIJ  *Ba = (Mat_SeqBAIJ*)mat->B->data;
972     PetscInt     max = 1,mbs = mat->mbs,tmp;
973     for (i=0; i<mbs; i++) {
974       tmp = Aa->i[i+1] - Aa->i[i] + Ba->i[i+1] - Ba->i[i]; /* row length */
975       if (max < tmp) { max = tmp; }
976     }
977     ierr = PetscMalloc(max*bs2*(sizeof(PetscInt)+sizeof(PetscScalar)),&mat->rowvalues);CHKERRQ(ierr);
978     mat->rowindices = (PetscInt*)(mat->rowvalues + max*bs2);
979   }
980 
981   if (row < brstart || row >= brend) SETERRQ(PETSC_ERR_SUP,"Only local rows")
982   lrow = row - brstart;  /* local row index */
983 
984   pvA = &vworkA; pcA = &cworkA; pvB = &vworkB; pcB = &cworkB;
985   if (!v)   {pvA = 0; pvB = 0;}
986   if (!idx) {pcA = 0; if (!v) pcB = 0;}
987   ierr = (*mat->A->ops->getrow)(mat->A,lrow,&nzA,pcA,pvA);CHKERRQ(ierr);
988   ierr = (*mat->B->ops->getrow)(mat->B,lrow,&nzB,pcB,pvB);CHKERRQ(ierr);
989   nztot = nzA + nzB;
990 
991   cmap  = mat->garray;
992   if (v  || idx) {
993     if (nztot) {
994       /* Sort by increasing column numbers, assuming A and B already sorted */
995       PetscInt imark = -1;
996       if (v) {
997         *v = v_p = mat->rowvalues;
998         for (i=0; i<nzB; i++) {
999           if (cmap[cworkB[i]/bs] < cstart)   v_p[i] = vworkB[i];
1000           else break;
1001         }
1002         imark = i;
1003         for (i=0; i<nzA; i++)     v_p[imark+i] = vworkA[i];
1004         for (i=imark; i<nzB; i++) v_p[nzA+i]   = vworkB[i];
1005       }
1006       if (idx) {
1007         *idx = idx_p = mat->rowindices;
1008         if (imark > -1) {
1009           for (i=0; i<imark; i++) {
1010             idx_p[i] = cmap[cworkB[i]/bs]*bs + cworkB[i]%bs;
1011           }
1012         } else {
1013           for (i=0; i<nzB; i++) {
1014             if (cmap[cworkB[i]/bs] < cstart)
1015               idx_p[i] = cmap[cworkB[i]/bs]*bs + cworkB[i]%bs ;
1016             else break;
1017           }
1018           imark = i;
1019         }
1020         for (i=0; i<nzA; i++)     idx_p[imark+i] = cstart*bs + cworkA[i];
1021         for (i=imark; i<nzB; i++) idx_p[nzA+i]   = cmap[cworkB[i]/bs]*bs + cworkB[i]%bs ;
1022       }
1023     } else {
1024       if (idx) *idx = 0;
1025       if (v)   *v   = 0;
1026     }
1027   }
1028   *nz = nztot;
1029   ierr = (*mat->A->ops->restorerow)(mat->A,lrow,&nzA,pcA,pvA);CHKERRQ(ierr);
1030   ierr = (*mat->B->ops->restorerow)(mat->B,lrow,&nzB,pcB,pvB);CHKERRQ(ierr);
1031   PetscFunctionReturn(0);
1032 }
1033 
1034 #undef __FUNCT__
1035 #define __FUNCT__ "MatRestoreRow_MPISBAIJ"
1036 PetscErrorCode MatRestoreRow_MPISBAIJ(Mat mat,PetscInt row,PetscInt *nz,PetscInt **idx,PetscScalar **v)
1037 {
1038   Mat_MPISBAIJ *baij = (Mat_MPISBAIJ*)mat->data;
1039 
1040   PetscFunctionBegin;
1041   if (!baij->getrowactive) {
1042     SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"MatGetRow() must be called first");
1043   }
1044   baij->getrowactive = PETSC_FALSE;
1045   PetscFunctionReturn(0);
1046 }
1047 
1048 #undef __FUNCT__
1049 #define __FUNCT__ "MatGetRowUpperTriangular_MPISBAIJ"
1050 PetscErrorCode MatGetRowUpperTriangular_MPISBAIJ(Mat A)
1051 {
1052   Mat_MPISBAIJ   *a = (Mat_MPISBAIJ*)A->data;
1053   Mat_SeqSBAIJ   *aA = (Mat_SeqSBAIJ*)a->A->data;
1054 
1055   PetscFunctionBegin;
1056   aA->getrow_utriangular = PETSC_TRUE;
1057   PetscFunctionReturn(0);
1058 }
1059 #undef __FUNCT__
1060 #define __FUNCT__ "MatRestoreRowUpperTriangular_MPISBAIJ"
1061 PetscErrorCode MatRestoreRowUpperTriangular_MPISBAIJ(Mat A)
1062 {
1063   Mat_MPISBAIJ   *a = (Mat_MPISBAIJ*)A->data;
1064   Mat_SeqSBAIJ   *aA = (Mat_SeqSBAIJ*)a->A->data;
1065 
1066   PetscFunctionBegin;
1067   aA->getrow_utriangular = PETSC_FALSE;
1068   PetscFunctionReturn(0);
1069 }
1070 
1071 #undef __FUNCT__
1072 #define __FUNCT__ "MatRealPart_MPISBAIJ"
1073 PetscErrorCode MatRealPart_MPISBAIJ(Mat A)
1074 {
1075   Mat_MPISBAIJ   *a = (Mat_MPISBAIJ*)A->data;
1076   PetscErrorCode ierr;
1077 
1078   PetscFunctionBegin;
1079   ierr = MatRealPart(a->A);CHKERRQ(ierr);
1080   ierr = MatRealPart(a->B);CHKERRQ(ierr);
1081   PetscFunctionReturn(0);
1082 }
1083 
1084 #undef __FUNCT__
1085 #define __FUNCT__ "MatImaginaryPart_MPISBAIJ"
1086 PetscErrorCode MatImaginaryPart_MPISBAIJ(Mat A)
1087 {
1088   Mat_MPISBAIJ   *a = (Mat_MPISBAIJ*)A->data;
1089   PetscErrorCode ierr;
1090 
1091   PetscFunctionBegin;
1092   ierr = MatImaginaryPart(a->A);CHKERRQ(ierr);
1093   ierr = MatImaginaryPart(a->B);CHKERRQ(ierr);
1094   PetscFunctionReturn(0);
1095 }
1096 
1097 #undef __FUNCT__
1098 #define __FUNCT__ "MatZeroEntries_MPISBAIJ"
1099 PetscErrorCode MatZeroEntries_MPISBAIJ(Mat A)
1100 {
1101   Mat_MPISBAIJ   *l = (Mat_MPISBAIJ*)A->data;
1102   PetscErrorCode ierr;
1103 
1104   PetscFunctionBegin;
1105   ierr = MatZeroEntries(l->A);CHKERRQ(ierr);
1106   ierr = MatZeroEntries(l->B);CHKERRQ(ierr);
1107   PetscFunctionReturn(0);
1108 }
1109 
1110 #undef __FUNCT__
1111 #define __FUNCT__ "MatGetInfo_MPISBAIJ"
1112 PetscErrorCode MatGetInfo_MPISBAIJ(Mat matin,MatInfoType flag,MatInfo *info)
1113 {
1114   Mat_MPISBAIJ   *a = (Mat_MPISBAIJ*)matin->data;
1115   Mat            A = a->A,B = a->B;
1116   PetscErrorCode ierr;
1117   PetscReal      isend[5],irecv[5];
1118 
1119   PetscFunctionBegin;
1120   info->block_size     = (PetscReal)matin->rmap.bs;
1121   ierr = MatGetInfo(A,MAT_LOCAL,info);CHKERRQ(ierr);
1122   isend[0] = info->nz_used; isend[1] = info->nz_allocated; isend[2] = info->nz_unneeded;
1123   isend[3] = info->memory;  isend[4] = info->mallocs;
1124   ierr = MatGetInfo(B,MAT_LOCAL,info);CHKERRQ(ierr);
1125   isend[0] += info->nz_used; isend[1] += info->nz_allocated; isend[2] += info->nz_unneeded;
1126   isend[3] += info->memory;  isend[4] += info->mallocs;
1127   if (flag == MAT_LOCAL) {
1128     info->nz_used      = isend[0];
1129     info->nz_allocated = isend[1];
1130     info->nz_unneeded  = isend[2];
1131     info->memory       = isend[3];
1132     info->mallocs      = isend[4];
1133   } else if (flag == MAT_GLOBAL_MAX) {
1134     ierr = MPI_Allreduce(isend,irecv,5,MPIU_REAL,MPI_MAX,((PetscObject)matin)->comm);CHKERRQ(ierr);
1135     info->nz_used      = irecv[0];
1136     info->nz_allocated = irecv[1];
1137     info->nz_unneeded  = irecv[2];
1138     info->memory       = irecv[3];
1139     info->mallocs      = irecv[4];
1140   } else if (flag == MAT_GLOBAL_SUM) {
1141     ierr = MPI_Allreduce(isend,irecv,5,MPIU_REAL,MPI_SUM,((PetscObject)matin)->comm);CHKERRQ(ierr);
1142     info->nz_used      = irecv[0];
1143     info->nz_allocated = irecv[1];
1144     info->nz_unneeded  = irecv[2];
1145     info->memory       = irecv[3];
1146     info->mallocs      = irecv[4];
1147   } else {
1148     SETERRQ1(PETSC_ERR_ARG_WRONG,"Unknown MatInfoType argument %d",(int)flag);
1149   }
1150   info->rows_global       = (PetscReal)A->rmap.N;
1151   info->columns_global    = (PetscReal)A->cmap.N;
1152   info->rows_local        = (PetscReal)A->rmap.N;
1153   info->columns_local     = (PetscReal)A->cmap.N;
1154   info->fill_ratio_given  = 0; /* no parallel LU/ILU/Cholesky */
1155   info->fill_ratio_needed = 0;
1156   info->factor_mallocs    = 0;
1157   PetscFunctionReturn(0);
1158 }
1159 
1160 #undef __FUNCT__
1161 #define __FUNCT__ "MatSetOption_MPISBAIJ"
1162 PetscErrorCode MatSetOption_MPISBAIJ(Mat A,MatOption op,PetscTruth flg)
1163 {
1164   Mat_MPISBAIJ   *a = (Mat_MPISBAIJ*)A->data;
1165   Mat_SeqSBAIJ   *aA = (Mat_SeqSBAIJ*)a->A->data;
1166   PetscErrorCode ierr;
1167 
1168   PetscFunctionBegin;
1169   switch (op) {
1170   case MAT_NEW_NONZERO_LOCATIONS:
1171   case MAT_NEW_NONZERO_ALLOCATION_ERR:
1172   case MAT_KEEP_ZEROED_ROWS:
1173   case MAT_NEW_NONZERO_LOCATION_ERR:
1174     ierr = MatSetOption(a->A,op,flg);CHKERRQ(ierr);
1175     ierr = MatSetOption(a->B,op,flg);CHKERRQ(ierr);
1176     break;
1177   case MAT_ROW_ORIENTED:
1178     a->roworiented = flg;
1179     ierr = MatSetOption(a->A,op,flg);CHKERRQ(ierr);
1180     ierr = MatSetOption(a->B,op,flg);CHKERRQ(ierr);
1181     break;
1182   case MAT_NEW_DIAGONALS:
1183     ierr = PetscInfo1(A,"Option %s ignored\n",MatOptions[op]);CHKERRQ(ierr);
1184     break;
1185   case MAT_IGNORE_OFF_PROC_ENTRIES:
1186     a->donotstash = flg;
1187     break;
1188   case MAT_USE_HASH_TABLE:
1189     a->ht_flag = flg;
1190     break;
1191   case MAT_HERMITIAN:
1192     if (flg) SETERRQ(PETSC_ERR_SUP,"Matrix must be symmetric");
1193   case MAT_SYMMETRIC:
1194   case MAT_STRUCTURALLY_SYMMETRIC:
1195   case MAT_SYMMETRY_ETERNAL:
1196     if (!flg) SETERRQ(PETSC_ERR_SUP,"Matrix must be symmetric");
1197     ierr = PetscInfo1(A,"Option %s ignored\n",MatOptions[op]);CHKERRQ(ierr);
1198     break;
1199   case MAT_IGNORE_LOWER_TRIANGULAR:
1200     aA->ignore_ltriangular = flg;
1201     break;
1202   case MAT_ERROR_LOWER_TRIANGULAR:
1203     aA->ignore_ltriangular = flg;
1204     break;
1205   case MAT_GETROW_UPPERTRIANGULAR:
1206     aA->getrow_utriangular = flg;
1207     break;
1208   default:
1209     SETERRQ1(PETSC_ERR_SUP,"unknown option %d",op);
1210   }
1211   PetscFunctionReturn(0);
1212 }
1213 
1214 #undef __FUNCT__
1215 #define __FUNCT__ "MatTranspose_MPISBAIJ"
1216 PetscErrorCode MatTranspose_MPISBAIJ(Mat A,Mat *B)
1217 {
1218   PetscErrorCode ierr;
1219   PetscFunctionBegin;
1220   ierr = MatDuplicate(A,MAT_COPY_VALUES,B);CHKERRQ(ierr);
1221   PetscFunctionReturn(0);
1222 }
1223 
1224 #undef __FUNCT__
1225 #define __FUNCT__ "MatDiagonalScale_MPISBAIJ"
1226 PetscErrorCode MatDiagonalScale_MPISBAIJ(Mat mat,Vec ll,Vec rr)
1227 {
1228   Mat_MPISBAIJ   *baij = (Mat_MPISBAIJ*)mat->data;
1229   Mat            a=baij->A, b=baij->B;
1230   PetscErrorCode ierr;
1231   PetscInt       nv,m,n;
1232   PetscTruth     flg;
1233 
1234   PetscFunctionBegin;
1235   if (ll != rr){
1236     ierr = VecEqual(ll,rr,&flg);CHKERRQ(ierr);
1237     if (!flg)
1238       SETERRQ(PETSC_ERR_ARG_OUTOFRANGE,"For symmetric format, left and right scaling vectors must be same\n");
1239   }
1240   if (!ll) PetscFunctionReturn(0);
1241 
1242   ierr = MatGetLocalSize(mat,&m,&n);CHKERRQ(ierr);
1243   if (m != n) SETERRQ2(PETSC_ERR_ARG_SIZ,"For symmetric format, local size %d %d must be same",m,n);
1244 
1245   ierr = VecGetLocalSize(rr,&nv);CHKERRQ(ierr);
1246   if (nv!=n) SETERRQ(PETSC_ERR_ARG_SIZ,"Left and right vector non-conforming local size");
1247 
1248   ierr = VecScatterBegin(baij->Mvctx,rr,baij->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1249 
1250   /* left diagonalscale the off-diagonal part */
1251   ierr = (*b->ops->diagonalscale)(b,ll,PETSC_NULL);CHKERRQ(ierr);
1252 
1253   /* scale the diagonal part */
1254   ierr = (*a->ops->diagonalscale)(a,ll,rr);CHKERRQ(ierr);
1255 
1256   /* right diagonalscale the off-diagonal part */
1257   ierr = VecScatterEnd(baij->Mvctx,rr,baij->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
1258   ierr = (*b->ops->diagonalscale)(b,PETSC_NULL,baij->lvec);CHKERRQ(ierr);
1259   PetscFunctionReturn(0);
1260 }
1261 
1262 #undef __FUNCT__
1263 #define __FUNCT__ "MatSetUnfactored_MPISBAIJ"
1264 PetscErrorCode MatSetUnfactored_MPISBAIJ(Mat A)
1265 {
1266   Mat_MPISBAIJ   *a = (Mat_MPISBAIJ*)A->data;
1267   PetscErrorCode ierr;
1268 
1269   PetscFunctionBegin;
1270   ierr = MatSetUnfactored(a->A);CHKERRQ(ierr);
1271   PetscFunctionReturn(0);
1272 }
1273 
1274 static PetscErrorCode MatDuplicate_MPISBAIJ(Mat,MatDuplicateOption,Mat *);
1275 
1276 #undef __FUNCT__
1277 #define __FUNCT__ "MatEqual_MPISBAIJ"
1278 PetscErrorCode MatEqual_MPISBAIJ(Mat A,Mat B,PetscTruth *flag)
1279 {
1280   Mat_MPISBAIJ   *matB = (Mat_MPISBAIJ*)B->data,*matA = (Mat_MPISBAIJ*)A->data;
1281   Mat            a,b,c,d;
1282   PetscTruth     flg;
1283   PetscErrorCode ierr;
1284 
1285   PetscFunctionBegin;
1286   a = matA->A; b = matA->B;
1287   c = matB->A; d = matB->B;
1288 
1289   ierr = MatEqual(a,c,&flg);CHKERRQ(ierr);
1290   if (flg) {
1291     ierr = MatEqual(b,d,&flg);CHKERRQ(ierr);
1292   }
1293   ierr = MPI_Allreduce(&flg,flag,1,MPI_INT,MPI_LAND,((PetscObject)A)->comm);CHKERRQ(ierr);
1294   PetscFunctionReturn(0);
1295 }
1296 
1297 #undef __FUNCT__
1298 #define __FUNCT__ "MatCopy_MPISBAIJ"
1299 PetscErrorCode MatCopy_MPISBAIJ(Mat A,Mat B,MatStructure str)
1300 {
1301   PetscErrorCode ierr;
1302   Mat_MPISBAIJ   *a = (Mat_MPISBAIJ *)A->data;
1303   Mat_MPISBAIJ   *b = (Mat_MPISBAIJ *)B->data;
1304 
1305   PetscFunctionBegin;
1306   /* If the two matrices don't have the same copy implementation, they aren't compatible for fast copy. */
1307   if ((str != SAME_NONZERO_PATTERN) || (A->ops->copy != B->ops->copy)) {
1308     ierr = MatGetRowUpperTriangular(A);CHKERRQ(ierr);
1309     ierr = MatCopy_Basic(A,B,str);CHKERRQ(ierr);
1310     ierr = MatRestoreRowUpperTriangular(A);CHKERRQ(ierr);
1311   } else {
1312     ierr = MatCopy(a->A,b->A,str);CHKERRQ(ierr);
1313     ierr = MatCopy(a->B,b->B,str);CHKERRQ(ierr);
1314   }
1315   PetscFunctionReturn(0);
1316 }
1317 
1318 #undef __FUNCT__
1319 #define __FUNCT__ "MatSetUpPreallocation_MPISBAIJ"
1320 PetscErrorCode MatSetUpPreallocation_MPISBAIJ(Mat A)
1321 {
1322   PetscErrorCode ierr;
1323 
1324   PetscFunctionBegin;
1325   ierr = MatMPISBAIJSetPreallocation(A,PetscMax(A->rmap.bs,1),PETSC_DEFAULT,0,PETSC_DEFAULT,0);CHKERRQ(ierr);
1326   PetscFunctionReturn(0);
1327 }
1328 
1329 #include "petscblaslapack.h"
1330 #undef __FUNCT__
1331 #define __FUNCT__ "MatAXPY_MPISBAIJ"
1332 PetscErrorCode MatAXPY_MPISBAIJ(Mat Y,PetscScalar a,Mat X,MatStructure str)
1333 {
1334   PetscErrorCode ierr;
1335   Mat_MPISBAIJ   *xx=(Mat_MPISBAIJ *)X->data,*yy=(Mat_MPISBAIJ *)Y->data;
1336   PetscBLASInt   bnz,one=1;
1337   Mat_SeqSBAIJ   *xa,*ya;
1338   Mat_SeqBAIJ    *xb,*yb;
1339 
1340   PetscFunctionBegin;
1341   if (str == SAME_NONZERO_PATTERN) {
1342     PetscScalar alpha = a;
1343     xa = (Mat_SeqSBAIJ *)xx->A->data;
1344     ya = (Mat_SeqSBAIJ *)yy->A->data;
1345     bnz = PetscBLASIntCast(xa->nz);
1346     BLASaxpy_(&bnz,&alpha,xa->a,&one,ya->a,&one);
1347     xb = (Mat_SeqBAIJ *)xx->B->data;
1348     yb = (Mat_SeqBAIJ *)yy->B->data;
1349     bnz = PetscBLASIntCast(xb->nz);
1350     BLASaxpy_(&bnz,&alpha,xb->a,&one,yb->a,&one);
1351   } else {
1352     ierr = MatGetRowUpperTriangular(X);CHKERRQ(ierr);
1353     ierr = MatAXPY_Basic(Y,a,X,str);CHKERRQ(ierr);
1354     ierr = MatRestoreRowUpperTriangular(X);CHKERRQ(ierr);
1355   }
1356   PetscFunctionReturn(0);
1357 }
1358 
1359 #undef __FUNCT__
1360 #define __FUNCT__ "MatGetSubMatrices_MPISBAIJ"
1361 PetscErrorCode MatGetSubMatrices_MPISBAIJ(Mat A,PetscInt n,const IS irow[],const IS icol[],MatReuse scall,Mat *B[])
1362 {
1363   PetscErrorCode ierr;
1364   PetscInt       i;
1365   PetscTruth     flg;
1366 
1367   PetscFunctionBegin;
1368   for (i=0; i<n; i++) {
1369     ierr = ISEqual(irow[i],icol[i],&flg);CHKERRQ(ierr);
1370     if (!flg) {
1371       SETERRQ(PETSC_ERR_SUP,"Can only get symmetric submatrix for MPISBAIJ matrices");
1372     }
1373   }
1374   ierr = MatGetSubMatrices_MPIBAIJ(A,n,irow,icol,scall,B);CHKERRQ(ierr);
1375   PetscFunctionReturn(0);
1376 }
1377 
1378 
1379 /* -------------------------------------------------------------------*/
1380 static struct _MatOps MatOps_Values = {
1381        MatSetValues_MPISBAIJ,
1382        MatGetRow_MPISBAIJ,
1383        MatRestoreRow_MPISBAIJ,
1384        MatMult_MPISBAIJ,
1385 /* 4*/ MatMultAdd_MPISBAIJ,
1386        MatMult_MPISBAIJ,       /* transpose versions are same as non-transpose */
1387        MatMultAdd_MPISBAIJ,
1388        0,
1389        0,
1390        0,
1391 /*10*/ 0,
1392        0,
1393        0,
1394        MatRelax_MPISBAIJ,
1395        MatTranspose_MPISBAIJ,
1396 /*15*/ MatGetInfo_MPISBAIJ,
1397        MatEqual_MPISBAIJ,
1398        MatGetDiagonal_MPISBAIJ,
1399        MatDiagonalScale_MPISBAIJ,
1400        MatNorm_MPISBAIJ,
1401 /*20*/ MatAssemblyBegin_MPISBAIJ,
1402        MatAssemblyEnd_MPISBAIJ,
1403        0,
1404        MatSetOption_MPISBAIJ,
1405        MatZeroEntries_MPISBAIJ,
1406 /*25*/ 0,
1407        0,
1408        0,
1409        0,
1410        0,
1411 /*30*/ MatSetUpPreallocation_MPISBAIJ,
1412        0,
1413        0,
1414        0,
1415        0,
1416 /*35*/ MatDuplicate_MPISBAIJ,
1417        0,
1418        0,
1419        0,
1420        0,
1421 /*40*/ MatAXPY_MPISBAIJ,
1422        MatGetSubMatrices_MPISBAIJ,
1423        MatIncreaseOverlap_MPISBAIJ,
1424        MatGetValues_MPISBAIJ,
1425        MatCopy_MPISBAIJ,
1426 /*45*/ 0,
1427        MatScale_MPISBAIJ,
1428        0,
1429        0,
1430        0,
1431 /*50*/ 0,
1432        0,
1433        0,
1434        0,
1435        0,
1436 /*55*/ 0,
1437        0,
1438        MatSetUnfactored_MPISBAIJ,
1439        0,
1440        MatSetValuesBlocked_MPISBAIJ,
1441 /*60*/ 0,
1442        0,
1443        0,
1444        0,
1445        0,
1446 /*65*/ 0,
1447        0,
1448        0,
1449        0,
1450        0,
1451 /*70*/ MatGetRowMaxAbs_MPISBAIJ,
1452        0,
1453        0,
1454        0,
1455        0,
1456 /*75*/ 0,
1457        0,
1458        0,
1459        0,
1460        0,
1461 /*80*/ 0,
1462        0,
1463        0,
1464        0,
1465        MatLoad_MPISBAIJ,
1466 /*85*/ 0,
1467        0,
1468        0,
1469        0,
1470        0,
1471 /*90*/ 0,
1472        0,
1473        0,
1474        0,
1475        0,
1476 /*95*/ 0,
1477        0,
1478        0,
1479        0,
1480        0,
1481 /*100*/0,
1482        0,
1483        0,
1484        0,
1485        0,
1486 /*105*/0,
1487        MatRealPart_MPISBAIJ,
1488        MatImaginaryPart_MPISBAIJ,
1489        MatGetRowUpperTriangular_MPISBAIJ,
1490        MatRestoreRowUpperTriangular_MPISBAIJ
1491 };
1492 
1493 
1494 EXTERN_C_BEGIN
1495 #undef __FUNCT__
1496 #define __FUNCT__ "MatGetDiagonalBlock_MPISBAIJ"
1497 PetscErrorCode PETSCMAT_DLLEXPORT MatGetDiagonalBlock_MPISBAIJ(Mat A,PetscTruth *iscopy,MatReuse reuse,Mat *a)
1498 {
1499   PetscFunctionBegin;
1500   *a      = ((Mat_MPISBAIJ *)A->data)->A;
1501   *iscopy = PETSC_FALSE;
1502   PetscFunctionReturn(0);
1503 }
1504 EXTERN_C_END
1505 
1506 EXTERN_C_BEGIN
1507 #undef __FUNCT__
1508 #define __FUNCT__ "MatMPISBAIJSetPreallocation_MPISBAIJ"
1509 PetscErrorCode PETSCMAT_DLLEXPORT MatMPISBAIJSetPreallocation_MPISBAIJ(Mat B,PetscInt bs,PetscInt d_nz,PetscInt *d_nnz,PetscInt o_nz,PetscInt *o_nnz)
1510 {
1511   Mat_MPISBAIJ   *b;
1512   PetscErrorCode ierr;
1513   PetscInt       i,mbs,Mbs;
1514 
1515   PetscFunctionBegin;
1516   ierr = PetscOptionsBegin(((PetscObject)B)->comm,((PetscObject)B)->prefix,"Options for MPISBAIJ matrix","Mat");CHKERRQ(ierr);
1517     ierr = PetscOptionsInt("-mat_block_size","Set the blocksize used to store the matrix","MatMPIBAIJSetPreallocation",bs,&bs,PETSC_NULL);CHKERRQ(ierr);
1518   ierr = PetscOptionsEnd();CHKERRQ(ierr);
1519 
1520   if (bs < 1) SETERRQ(PETSC_ERR_ARG_OUTOFRANGE,"Invalid block size specified, must be positive");
1521   if (d_nz == PETSC_DECIDE || d_nz == PETSC_DEFAULT) d_nz = 3;
1522   if (o_nz == PETSC_DECIDE || o_nz == PETSC_DEFAULT) o_nz = 1;
1523   if (d_nz < 0) SETERRQ1(PETSC_ERR_ARG_OUTOFRANGE,"d_nz cannot be less than 0: value %D",d_nz);
1524   if (o_nz < 0) SETERRQ1(PETSC_ERR_ARG_OUTOFRANGE,"o_nz cannot be less than 0: value %D",o_nz);
1525 
1526   B->rmap.bs = B->cmap.bs = bs;
1527   ierr = PetscMapSetUp(&B->rmap);CHKERRQ(ierr);
1528   ierr = PetscMapSetUp(&B->cmap);CHKERRQ(ierr);
1529 
1530   if (d_nnz) {
1531     for (i=0; i<B->rmap.n/bs; i++) {
1532       if (d_nnz[i] < 0) SETERRQ2(PETSC_ERR_ARG_OUTOFRANGE,"d_nnz cannot be less than -1: local row %D value %D",i,d_nnz[i]);
1533     }
1534   }
1535   if (o_nnz) {
1536     for (i=0; i<B->rmap.n/bs; i++) {
1537       if (o_nnz[i] < 0) SETERRQ2(PETSC_ERR_ARG_OUTOFRANGE,"o_nnz cannot be less than -1: local row %D value %D",i,o_nnz[i]);
1538     }
1539   }
1540   B->preallocated = PETSC_TRUE;
1541 
1542   b   = (Mat_MPISBAIJ*)B->data;
1543   mbs = B->rmap.n/bs;
1544   Mbs = B->rmap.N/bs;
1545   if (mbs*bs != B->rmap.n) {
1546     SETERRQ2(PETSC_ERR_ARG_SIZ,"No of local rows %D must be divisible by blocksize %D",B->rmap.N,bs);
1547   }
1548 
1549   B->rmap.bs  = bs;
1550   b->bs2 = bs*bs;
1551   b->mbs = mbs;
1552   b->nbs = mbs;
1553   b->Mbs = Mbs;
1554   b->Nbs = Mbs;
1555 
1556   for (i=0; i<=b->size; i++) {
1557     b->rangebs[i] = B->rmap.range[i]/bs;
1558   }
1559   b->rstartbs = B->rmap.rstart/bs;
1560   b->rendbs   = B->rmap.rend/bs;
1561 
1562   b->cstartbs = B->cmap.rstart/bs;
1563   b->cendbs   = B->cmap.rend/bs;
1564 
1565   ierr = MatCreate(PETSC_COMM_SELF,&b->A);CHKERRQ(ierr);
1566   ierr = MatSetSizes(b->A,B->rmap.n,B->cmap.n,B->rmap.n,B->cmap.n);CHKERRQ(ierr);
1567   ierr = MatSetType(b->A,MATSEQSBAIJ);CHKERRQ(ierr);
1568   ierr = MatSeqSBAIJSetPreallocation(b->A,bs,d_nz,d_nnz);CHKERRQ(ierr);
1569   ierr = PetscLogObjectParent(B,b->A);CHKERRQ(ierr);
1570 
1571   ierr = MatCreate(PETSC_COMM_SELF,&b->B);CHKERRQ(ierr);
1572   ierr = MatSetSizes(b->B,B->rmap.n,B->cmap.N,B->rmap.n,B->cmap.N);CHKERRQ(ierr);
1573   ierr = MatSetType(b->B,MATSEQBAIJ);CHKERRQ(ierr);
1574   ierr = MatSeqBAIJSetPreallocation(b->B,bs,o_nz,o_nnz);CHKERRQ(ierr);
1575   ierr = PetscLogObjectParent(B,b->B);CHKERRQ(ierr);
1576 
1577   /* build cache for off array entries formed */
1578   ierr = MatStashCreate_Private(((PetscObject)B)->comm,bs,&B->bstash);CHKERRQ(ierr);
1579 
1580   PetscFunctionReturn(0);
1581 }
1582 EXTERN_C_END
1583 
1584 /*MC
1585    MATMPISBAIJ - MATMPISBAIJ = "mpisbaij" - A matrix type to be used for distributed symmetric sparse block matrices,
1586    based on block compressed sparse row format.  Only the upper triangular portion of the matrix is stored.
1587 
1588    Options Database Keys:
1589 . -mat_type mpisbaij - sets the matrix type to "mpisbaij" during a call to MatSetFromOptions()
1590 
1591   Level: beginner
1592 
1593 .seealso: MatCreateMPISBAIJ
1594 M*/
1595 
1596 EXTERN_C_BEGIN
1597 #undef __FUNCT__
1598 #define __FUNCT__ "MatCreate_MPISBAIJ"
1599 PetscErrorCode PETSCMAT_DLLEXPORT MatCreate_MPISBAIJ(Mat B)
1600 {
1601   Mat_MPISBAIJ   *b;
1602   PetscErrorCode ierr;
1603   PetscTruth     flg;
1604 
1605   PetscFunctionBegin;
1606 
1607   ierr    = PetscNewLog(B,Mat_MPISBAIJ,&b);CHKERRQ(ierr);
1608   B->data = (void*)b;
1609   ierr    = PetscMemcpy(B->ops,&MatOps_Values,sizeof(struct _MatOps));CHKERRQ(ierr);
1610 
1611   B->ops->destroy    = MatDestroy_MPISBAIJ;
1612   B->ops->view       = MatView_MPISBAIJ;
1613   B->mapping    = 0;
1614   B->factor     = 0;
1615   B->assembled  = PETSC_FALSE;
1616 
1617   B->insertmode = NOT_SET_VALUES;
1618   ierr = MPI_Comm_rank(((PetscObject)B)->comm,&b->rank);CHKERRQ(ierr);
1619   ierr = MPI_Comm_size(((PetscObject)B)->comm,&b->size);CHKERRQ(ierr);
1620 
1621   /* build local table of row and column ownerships */
1622   ierr  = PetscMalloc((b->size+2)*sizeof(PetscInt),&b->rangebs);CHKERRQ(ierr);
1623 
1624   /* build cache for off array entries formed */
1625   ierr = MatStashCreate_Private(((PetscObject)B)->comm,1,&B->stash);CHKERRQ(ierr);
1626   b->donotstash  = PETSC_FALSE;
1627   b->colmap      = PETSC_NULL;
1628   b->garray      = PETSC_NULL;
1629   b->roworiented = PETSC_TRUE;
1630 
1631 #if defined(PETSC_USE_MAT_SINGLE)
1632   /* stuff for MatSetValues_XXX in single precision */
1633   b->setvalueslen     = 0;
1634   b->setvaluescopy    = PETSC_NULL;
1635 #endif
1636 
1637   /* stuff used in block assembly */
1638   b->barray       = 0;
1639 
1640   /* stuff used for matrix vector multiply */
1641   b->lvec         = 0;
1642   b->Mvctx        = 0;
1643   b->slvec0       = 0;
1644   b->slvec0b      = 0;
1645   b->slvec1       = 0;
1646   b->slvec1a      = 0;
1647   b->slvec1b      = 0;
1648   b->sMvctx       = 0;
1649 
1650   /* stuff for MatGetRow() */
1651   b->rowindices   = 0;
1652   b->rowvalues    = 0;
1653   b->getrowactive = PETSC_FALSE;
1654 
1655   /* hash table stuff */
1656   b->ht           = 0;
1657   b->hd           = 0;
1658   b->ht_size      = 0;
1659   b->ht_flag      = PETSC_FALSE;
1660   b->ht_fact      = 0;
1661   b->ht_total_ct  = 0;
1662   b->ht_insert_ct = 0;
1663 
1664   b->in_loc       = 0;
1665   b->v_loc        = 0;
1666   b->n_loc        = 0;
1667   ierr = PetscOptionsBegin(((PetscObject)B)->comm,PETSC_NULL,"Options for loading MPISBAIJ matrix 1","Mat");CHKERRQ(ierr);
1668     ierr = PetscOptionsTruth("-mat_use_hash_table","Use hash table to save memory in constructing matrix","MatSetOption",PETSC_FALSE,&flg,PETSC_NULL);CHKERRQ(ierr);
1669     if (flg) {
1670       PetscReal fact = 1.39;
1671       ierr = MatSetOption(B,MAT_USE_HASH_TABLE,PETSC_TRUE);CHKERRQ(ierr);
1672       ierr = PetscOptionsReal("-mat_use_hash_table","Use hash table factor","MatMPIBAIJSetHashTableFactor",fact,&fact,PETSC_NULL);CHKERRQ(ierr);
1673       if (fact <= 1.0) fact = 1.39;
1674       ierr = MatMPIBAIJSetHashTableFactor(B,fact);CHKERRQ(ierr);
1675       ierr = PetscInfo1(B,"Hash table Factor used %5.2f\n",fact);CHKERRQ(ierr);
1676     }
1677   ierr = PetscOptionsEnd();CHKERRQ(ierr);
1678 
1679   ierr = PetscObjectComposeFunctionDynamic((PetscObject)B,"MatStoreValues_C",
1680                                      "MatStoreValues_MPISBAIJ",
1681                                      MatStoreValues_MPISBAIJ);CHKERRQ(ierr);
1682   ierr = PetscObjectComposeFunctionDynamic((PetscObject)B,"MatRetrieveValues_C",
1683                                      "MatRetrieveValues_MPISBAIJ",
1684                                      MatRetrieveValues_MPISBAIJ);CHKERRQ(ierr);
1685   ierr = PetscObjectComposeFunctionDynamic((PetscObject)B,"MatGetDiagonalBlock_C",
1686                                      "MatGetDiagonalBlock_MPISBAIJ",
1687                                      MatGetDiagonalBlock_MPISBAIJ);CHKERRQ(ierr);
1688   ierr = PetscObjectComposeFunctionDynamic((PetscObject)B,"MatMPISBAIJSetPreallocation_C",
1689                                      "MatMPISBAIJSetPreallocation_MPISBAIJ",
1690                                      MatMPISBAIJSetPreallocation_MPISBAIJ);CHKERRQ(ierr);
1691   B->symmetric                  = PETSC_TRUE;
1692   B->structurally_symmetric     = PETSC_TRUE;
1693   B->symmetric_set              = PETSC_TRUE;
1694   B->structurally_symmetric_set = PETSC_TRUE;
1695   ierr = PetscObjectChangeTypeName((PetscObject)B,MATMPISBAIJ);CHKERRQ(ierr);
1696   PetscFunctionReturn(0);
1697 }
1698 EXTERN_C_END
1699 
1700 /*MC
1701    MATSBAIJ - MATSBAIJ = "sbaij" - A matrix type to be used for symmetric block sparse matrices.
1702 
1703    This matrix type is identical to MATSEQSBAIJ when constructed with a single process communicator,
1704    and MATMPISBAIJ otherwise.
1705 
1706    Options Database Keys:
1707 . -mat_type sbaij - sets the matrix type to "sbaij" during a call to MatSetFromOptions()
1708 
1709   Level: beginner
1710 
1711 .seealso: MatCreateMPISBAIJ,MATSEQSBAIJ,MATMPISBAIJ
1712 M*/
1713 
1714 EXTERN_C_BEGIN
1715 #undef __FUNCT__
1716 #define __FUNCT__ "MatCreate_SBAIJ"
1717 PetscErrorCode PETSCMAT_DLLEXPORT MatCreate_SBAIJ(Mat A)
1718 {
1719   PetscErrorCode ierr;
1720   PetscMPIInt    size;
1721 
1722   PetscFunctionBegin;
1723   ierr = MPI_Comm_size(((PetscObject)A)->comm,&size);CHKERRQ(ierr);
1724   if (size == 1) {
1725     ierr = MatSetType(A,MATSEQSBAIJ);CHKERRQ(ierr);
1726   } else {
1727     ierr = MatSetType(A,MATMPISBAIJ);CHKERRQ(ierr);
1728   }
1729   PetscFunctionReturn(0);
1730 }
1731 EXTERN_C_END
1732 
1733 #undef __FUNCT__
1734 #define __FUNCT__ "MatMPISBAIJSetPreallocation"
1735 /*@C
1736    MatMPISBAIJSetPreallocation - For good matrix assembly performance
1737    the user should preallocate the matrix storage by setting the parameters
1738    d_nz (or d_nnz) and o_nz (or o_nnz).  By setting these parameters accurately,
1739    performance can be increased by more than a factor of 50.
1740 
1741    Collective on Mat
1742 
1743    Input Parameters:
1744 +  A - the matrix
1745 .  bs   - size of blockk
1746 .  d_nz  - number of block nonzeros per block row in diagonal portion of local
1747            submatrix  (same for all local rows)
1748 .  d_nnz - array containing the number of block nonzeros in the various block rows
1749            in the upper triangular and diagonal part of the in diagonal portion of the local
1750            (possibly different for each block row) or PETSC_NULL.  You must leave room
1751            for the diagonal entry even if it is zero.
1752 .  o_nz  - number of block nonzeros per block row in the off-diagonal portion of local
1753            submatrix (same for all local rows).
1754 -  o_nnz - array containing the number of nonzeros in the various block rows of the
1755            off-diagonal portion of the local submatrix (possibly different for
1756            each block row) or PETSC_NULL.
1757 
1758 
1759    Options Database Keys:
1760 .   -mat_no_unroll - uses code that does not unroll the loops in the
1761                      block calculations (much slower)
1762 .   -mat_block_size - size of the blocks to use
1763 
1764    Notes:
1765 
1766    If PETSC_DECIDE or  PETSC_DETERMINE is used for a particular argument on one processor
1767    than it must be used on all processors that share the object for that argument.
1768 
1769    If the *_nnz parameter is given then the *_nz parameter is ignored
1770 
1771    Storage Information:
1772    For a square global matrix we define each processor's diagonal portion
1773    to be its local rows and the corresponding columns (a square submatrix);
1774    each processor's off-diagonal portion encompasses the remainder of the
1775    local matrix (a rectangular submatrix).
1776 
1777    The user can specify preallocated storage for the diagonal part of
1778    the local submatrix with either d_nz or d_nnz (not both).  Set
1779    d_nz=PETSC_DEFAULT and d_nnz=PETSC_NULL for PETSc to control dynamic
1780    memory allocation.  Likewise, specify preallocated storage for the
1781    off-diagonal part of the local submatrix with o_nz or o_nnz (not both).
1782 
1783    You can call MatGetInfo() to get information on how effective the preallocation was;
1784    for example the fields mallocs,nz_allocated,nz_used,nz_unneeded;
1785    You can also run with the option -info and look for messages with the string
1786    malloc in them to see if additional memory allocation was needed.
1787 
1788    Consider a processor that owns rows 3, 4 and 5 of a parallel matrix. In
1789    the figure below we depict these three local rows and all columns (0-11).
1790 
1791 .vb
1792            0 1 2 3 4 5 6 7 8 9 10 11
1793           -------------------
1794    row 3  |  o o o d d d o o o o o o
1795    row 4  |  o o o d d d o o o o o o
1796    row 5  |  o o o d d d o o o o o o
1797           -------------------
1798 .ve
1799 
1800    Thus, any entries in the d locations are stored in the d (diagonal)
1801    submatrix, and any entries in the o locations are stored in the
1802    o (off-diagonal) submatrix.  Note that the d matrix is stored in
1803    MatSeqSBAIJ format and the o submatrix in MATSEQBAIJ format.
1804 
1805    Now d_nz should indicate the number of block nonzeros per row in the upper triangular
1806    plus the diagonal part of the d matrix,
1807    and o_nz should indicate the number of block nonzeros per row in the o matrix.
1808    In general, for PDE problems in which most nonzeros are near the diagonal,
1809    one expects d_nz >> o_nz.   For large problems you MUST preallocate memory
1810    or you will get TERRIBLE performance; see the users' manual chapter on
1811    matrices.
1812 
1813    Level: intermediate
1814 
1815 .keywords: matrix, block, aij, compressed row, sparse, parallel
1816 
1817 .seealso: MatCreate(), MatCreateSeqSBAIJ(), MatSetValues(), MatCreateMPIBAIJ()
1818 @*/
1819 PetscErrorCode PETSCMAT_DLLEXPORT MatMPISBAIJSetPreallocation(Mat B,PetscInt bs,PetscInt d_nz,const PetscInt d_nnz[],PetscInt o_nz,const PetscInt o_nnz[])
1820 {
1821   PetscErrorCode ierr,(*f)(Mat,PetscInt,PetscInt,const PetscInt[],PetscInt,const PetscInt[]);
1822 
1823   PetscFunctionBegin;
1824   ierr = PetscObjectQueryFunction((PetscObject)B,"MatMPISBAIJSetPreallocation_C",(void (**)(void))&f);CHKERRQ(ierr);
1825   if (f) {
1826     ierr = (*f)(B,bs,d_nz,d_nnz,o_nz,o_nnz);CHKERRQ(ierr);
1827   }
1828   PetscFunctionReturn(0);
1829 }
1830 
1831 #undef __FUNCT__
1832 #define __FUNCT__ "MatCreateMPISBAIJ"
1833 /*@C
1834    MatCreateMPISBAIJ - Creates a sparse parallel matrix in symmetric block AIJ format
1835    (block compressed row).  For good matrix assembly performance
1836    the user should preallocate the matrix storage by setting the parameters
1837    d_nz (or d_nnz) and o_nz (or o_nnz).  By setting these parameters accurately,
1838    performance can be increased by more than a factor of 50.
1839 
1840    Collective on MPI_Comm
1841 
1842    Input Parameters:
1843 +  comm - MPI communicator
1844 .  bs   - size of blockk
1845 .  m - number of local rows (or PETSC_DECIDE to have calculated if M is given)
1846            This value should be the same as the local size used in creating the
1847            y vector for the matrix-vector product y = Ax.
1848 .  n - number of local columns (or PETSC_DECIDE to have calculated if N is given)
1849            This value should be the same as the local size used in creating the
1850            x vector for the matrix-vector product y = Ax.
1851 .  M - number of global rows (or PETSC_DETERMINE to have calculated if m is given)
1852 .  N - number of global columns (or PETSC_DETERMINE to have calculated if n is given)
1853 .  d_nz  - number of block nonzeros per block row in diagonal portion of local
1854            submatrix  (same for all local rows)
1855 .  d_nnz - array containing the number of block nonzeros in the various block rows
1856            in the upper triangular portion of the in diagonal portion of the local
1857            (possibly different for each block block row) or PETSC_NULL.
1858            You must leave room for the diagonal entry even if it is zero.
1859 .  o_nz  - number of block nonzeros per block row in the off-diagonal portion of local
1860            submatrix (same for all local rows).
1861 -  o_nnz - array containing the number of nonzeros in the various block rows of the
1862            off-diagonal portion of the local submatrix (possibly different for
1863            each block row) or PETSC_NULL.
1864 
1865    Output Parameter:
1866 .  A - the matrix
1867 
1868    Options Database Keys:
1869 .   -mat_no_unroll - uses code that does not unroll the loops in the
1870                      block calculations (much slower)
1871 .   -mat_block_size - size of the blocks to use
1872 .   -mat_mpi - use the parallel matrix data structures even on one processor
1873                (defaults to using SeqBAIJ format on one processor)
1874 
1875    It is recommended that one use the MatCreate(), MatSetType() and/or MatSetFromOptions(),
1876    MatXXXXSetPreallocation() paradgm instead of this routine directly. This is definitely
1877    true if you plan to use the external direct solvers such as SuperLU, MUMPS or Spooles.
1878    [MatXXXXSetPreallocation() is, for example, MatSeqAIJSetPreallocation]
1879 
1880    Notes:
1881    The number of rows and columns must be divisible by blocksize.
1882    This matrix type does not support complex Hermitian operation.
1883 
1884    The user MUST specify either the local or global matrix dimensions
1885    (possibly both).
1886 
1887    If PETSC_DECIDE or  PETSC_DETERMINE is used for a particular argument on one processor
1888    than it must be used on all processors that share the object for that argument.
1889 
1890    If the *_nnz parameter is given then the *_nz parameter is ignored
1891 
1892    Storage Information:
1893    For a square global matrix we define each processor's diagonal portion
1894    to be its local rows and the corresponding columns (a square submatrix);
1895    each processor's off-diagonal portion encompasses the remainder of the
1896    local matrix (a rectangular submatrix).
1897 
1898    The user can specify preallocated storage for the diagonal part of
1899    the local submatrix with either d_nz or d_nnz (not both).  Set
1900    d_nz=PETSC_DEFAULT and d_nnz=PETSC_NULL for PETSc to control dynamic
1901    memory allocation.  Likewise, specify preallocated storage for the
1902    off-diagonal part of the local submatrix with o_nz or o_nnz (not both).
1903 
1904    Consider a processor that owns rows 3, 4 and 5 of a parallel matrix. In
1905    the figure below we depict these three local rows and all columns (0-11).
1906 
1907 .vb
1908            0 1 2 3 4 5 6 7 8 9 10 11
1909           -------------------
1910    row 3  |  o o o d d d o o o o o o
1911    row 4  |  o o o d d d o o o o o o
1912    row 5  |  o o o d d d o o o o o o
1913           -------------------
1914 .ve
1915 
1916    Thus, any entries in the d locations are stored in the d (diagonal)
1917    submatrix, and any entries in the o locations are stored in the
1918    o (off-diagonal) submatrix.  Note that the d matrix is stored in
1919    MatSeqSBAIJ format and the o submatrix in MATSEQBAIJ format.
1920 
1921    Now d_nz should indicate the number of block nonzeros per row in the upper triangular
1922    plus the diagonal part of the d matrix,
1923    and o_nz should indicate the number of block nonzeros per row in the o matrix.
1924    In general, for PDE problems in which most nonzeros are near the diagonal,
1925    one expects d_nz >> o_nz.   For large problems you MUST preallocate memory
1926    or you will get TERRIBLE performance; see the users' manual chapter on
1927    matrices.
1928 
1929    Level: intermediate
1930 
1931 .keywords: matrix, block, aij, compressed row, sparse, parallel
1932 
1933 .seealso: MatCreate(), MatCreateSeqSBAIJ(), MatSetValues(), MatCreateMPIBAIJ()
1934 @*/
1935 
1936 PetscErrorCode PETSCMAT_DLLEXPORT MatCreateMPISBAIJ(MPI_Comm comm,PetscInt bs,PetscInt m,PetscInt n,PetscInt M,PetscInt N,PetscInt d_nz,const PetscInt d_nnz[],PetscInt o_nz,const PetscInt o_nnz[],Mat *A)
1937 {
1938   PetscErrorCode ierr;
1939   PetscMPIInt    size;
1940 
1941   PetscFunctionBegin;
1942   ierr = MatCreate(comm,A);CHKERRQ(ierr);
1943   ierr = MatSetSizes(*A,m,n,M,N);CHKERRQ(ierr);
1944   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
1945   if (size > 1) {
1946     ierr = MatSetType(*A,MATMPISBAIJ);CHKERRQ(ierr);
1947     ierr = MatMPISBAIJSetPreallocation(*A,bs,d_nz,d_nnz,o_nz,o_nnz);CHKERRQ(ierr);
1948   } else {
1949     ierr = MatSetType(*A,MATSEQSBAIJ);CHKERRQ(ierr);
1950     ierr = MatSeqSBAIJSetPreallocation(*A,bs,d_nz,d_nnz);CHKERRQ(ierr);
1951   }
1952   PetscFunctionReturn(0);
1953 }
1954 
1955 
1956 #undef __FUNCT__
1957 #define __FUNCT__ "MatDuplicate_MPISBAIJ"
1958 static PetscErrorCode MatDuplicate_MPISBAIJ(Mat matin,MatDuplicateOption cpvalues,Mat *newmat)
1959 {
1960   Mat            mat;
1961   Mat_MPISBAIJ   *a,*oldmat = (Mat_MPISBAIJ*)matin->data;
1962   PetscErrorCode ierr;
1963   PetscInt       len=0,nt,bs=matin->rmap.bs,mbs=oldmat->mbs;
1964   PetscScalar    *array;
1965 
1966   PetscFunctionBegin;
1967   *newmat       = 0;
1968   ierr = MatCreate(((PetscObject)matin)->comm,&mat);CHKERRQ(ierr);
1969   ierr = MatSetSizes(mat,matin->rmap.n,matin->cmap.n,matin->rmap.N,matin->cmap.N);CHKERRQ(ierr);
1970   ierr = MatSetType(mat,((PetscObject)matin)->type_name);CHKERRQ(ierr);
1971   ierr = PetscMemcpy(mat->ops,matin->ops,sizeof(struct _MatOps));CHKERRQ(ierr);
1972   ierr = PetscMapCopy(((PetscObject)matin)->comm,&matin->rmap,&mat->rmap);CHKERRQ(ierr);
1973   ierr = PetscMapCopy(((PetscObject)matin)->comm,&matin->cmap,&mat->cmap);CHKERRQ(ierr);
1974 
1975   mat->factor       = matin->factor;
1976   mat->preallocated = PETSC_TRUE;
1977   mat->assembled    = PETSC_TRUE;
1978   mat->insertmode   = NOT_SET_VALUES;
1979 
1980   a = (Mat_MPISBAIJ*)mat->data;
1981   a->bs2   = oldmat->bs2;
1982   a->mbs   = oldmat->mbs;
1983   a->nbs   = oldmat->nbs;
1984   a->Mbs   = oldmat->Mbs;
1985   a->Nbs   = oldmat->Nbs;
1986 
1987 
1988   a->size         = oldmat->size;
1989   a->rank         = oldmat->rank;
1990   a->donotstash   = oldmat->donotstash;
1991   a->roworiented  = oldmat->roworiented;
1992   a->rowindices   = 0;
1993   a->rowvalues    = 0;
1994   a->getrowactive = PETSC_FALSE;
1995   a->barray       = 0;
1996   a->rstartbs    = oldmat->rstartbs;
1997   a->rendbs      = oldmat->rendbs;
1998   a->cstartbs    = oldmat->cstartbs;
1999   a->cendbs      = oldmat->cendbs;
2000 
2001   /* hash table stuff */
2002   a->ht           = 0;
2003   a->hd           = 0;
2004   a->ht_size      = 0;
2005   a->ht_flag      = oldmat->ht_flag;
2006   a->ht_fact      = oldmat->ht_fact;
2007   a->ht_total_ct  = 0;
2008   a->ht_insert_ct = 0;
2009 
2010   ierr = PetscMemcpy(a->rangebs,oldmat->rangebs,(a->size+2)*sizeof(PetscInt));CHKERRQ(ierr);
2011   ierr = MatStashCreate_Private(((PetscObject)matin)->comm,1,&mat->stash);CHKERRQ(ierr);
2012   ierr = MatStashCreate_Private(((PetscObject)matin)->comm,matin->rmap.bs,&mat->bstash);CHKERRQ(ierr);
2013   if (oldmat->colmap) {
2014 #if defined (PETSC_USE_CTABLE)
2015     ierr = PetscTableCreateCopy(oldmat->colmap,&a->colmap);CHKERRQ(ierr);
2016 #else
2017     ierr = PetscMalloc((a->Nbs)*sizeof(PetscInt),&a->colmap);CHKERRQ(ierr);
2018     ierr = PetscLogObjectMemory(mat,(a->Nbs)*sizeof(PetscInt));CHKERRQ(ierr);
2019     ierr = PetscMemcpy(a->colmap,oldmat->colmap,(a->Nbs)*sizeof(PetscInt));CHKERRQ(ierr);
2020 #endif
2021   } else a->colmap = 0;
2022 
2023   if (oldmat->garray && (len = ((Mat_SeqBAIJ*)(oldmat->B->data))->nbs)) {
2024     ierr = PetscMalloc(len*sizeof(PetscInt),&a->garray);CHKERRQ(ierr);
2025     ierr = PetscLogObjectMemory(mat,len*sizeof(PetscInt));CHKERRQ(ierr);
2026     ierr = PetscMemcpy(a->garray,oldmat->garray,len*sizeof(PetscInt));CHKERRQ(ierr);
2027   } else a->garray = 0;
2028 
2029   ierr =  VecDuplicate(oldmat->lvec,&a->lvec);CHKERRQ(ierr);
2030   ierr = PetscLogObjectParent(mat,a->lvec);CHKERRQ(ierr);
2031   ierr =  VecScatterCopy(oldmat->Mvctx,&a->Mvctx);CHKERRQ(ierr);
2032   ierr = PetscLogObjectParent(mat,a->Mvctx);CHKERRQ(ierr);
2033 
2034   ierr =  VecDuplicate(oldmat->slvec0,&a->slvec0);CHKERRQ(ierr);
2035   ierr = PetscLogObjectParent(mat,a->slvec0);CHKERRQ(ierr);
2036   ierr =  VecDuplicate(oldmat->slvec1,&a->slvec1);CHKERRQ(ierr);
2037   ierr = PetscLogObjectParent(mat,a->slvec1);CHKERRQ(ierr);
2038 
2039   ierr = VecGetLocalSize(a->slvec1,&nt);CHKERRQ(ierr);
2040   ierr = VecGetArray(a->slvec1,&array);CHKERRQ(ierr);
2041   ierr = VecCreateSeqWithArray(PETSC_COMM_SELF,bs*mbs,array,&a->slvec1a);CHKERRQ(ierr);
2042   ierr = VecCreateSeqWithArray(PETSC_COMM_SELF,nt-bs*mbs,array+bs*mbs,&a->slvec1b);CHKERRQ(ierr);
2043   ierr = VecRestoreArray(a->slvec1,&array);CHKERRQ(ierr);
2044   ierr = VecGetArray(a->slvec0,&array);CHKERRQ(ierr);
2045   ierr = VecCreateSeqWithArray(PETSC_COMM_SELF,nt-bs*mbs,array+bs*mbs,&a->slvec0b);CHKERRQ(ierr);
2046   ierr = VecRestoreArray(a->slvec0,&array);CHKERRQ(ierr);
2047   ierr = PetscLogObjectParent(mat,a->slvec0);CHKERRQ(ierr);
2048   ierr = PetscLogObjectParent(mat,a->slvec1);CHKERRQ(ierr);
2049   ierr = PetscLogObjectParent(mat,a->slvec0b);CHKERRQ(ierr);
2050   ierr = PetscLogObjectParent(mat,a->slvec1a);CHKERRQ(ierr);
2051   ierr = PetscLogObjectParent(mat,a->slvec1b);CHKERRQ(ierr);
2052 
2053   /* ierr =  VecScatterCopy(oldmat->sMvctx,&a->sMvctx); - not written yet, replaced by the lazy trick: */
2054   ierr = PetscObjectReference((PetscObject)oldmat->sMvctx);CHKERRQ(ierr);
2055   a->sMvctx = oldmat->sMvctx;
2056   ierr = PetscLogObjectParent(mat,a->sMvctx);CHKERRQ(ierr);
2057 
2058   ierr =  MatDuplicate(oldmat->A,cpvalues,&a->A);CHKERRQ(ierr);
2059   ierr = PetscLogObjectParent(mat,a->A);CHKERRQ(ierr);
2060   ierr =  MatDuplicate(oldmat->B,cpvalues,&a->B);CHKERRQ(ierr);
2061   ierr = PetscLogObjectParent(mat,a->B);CHKERRQ(ierr);
2062   ierr = PetscFListDuplicate(((PetscObject)matin)->qlist,&((PetscObject)mat)->qlist);CHKERRQ(ierr);
2063   *newmat = mat;
2064   PetscFunctionReturn(0);
2065 }
2066 
2067 #include "petscsys.h"
2068 
2069 #undef __FUNCT__
2070 #define __FUNCT__ "MatLoad_MPISBAIJ"
2071 PetscErrorCode MatLoad_MPISBAIJ(PetscViewer viewer, MatType type,Mat *newmat)
2072 {
2073   Mat            A;
2074   PetscErrorCode ierr;
2075   PetscInt       i,nz,j,rstart,rend;
2076   PetscScalar    *vals,*buf;
2077   MPI_Comm       comm = ((PetscObject)viewer)->comm;
2078   MPI_Status     status;
2079   PetscMPIInt    rank,size,tag = ((PetscObject)viewer)->tag,*sndcounts = 0,*browners,maxnz,*rowners,*locrowlens,mmbs;
2080   PetscInt       header[4],*rowlengths = 0,M,N,m,*cols;
2081   PetscInt       *procsnz = 0,jj,*mycols,*ibuf;
2082   PetscInt       bs=1,Mbs,mbs,extra_rows;
2083   PetscInt       *dlens,*odlens,*mask,*masked1,*masked2,rowcount,odcount;
2084   PetscInt       dcount,kmax,k,nzcount,tmp;
2085   int            fd;
2086 
2087   PetscFunctionBegin;
2088   ierr = PetscOptionsBegin(comm,PETSC_NULL,"Options for loading MPISBAIJ matrix 2","Mat");CHKERRQ(ierr);
2089     ierr = PetscOptionsInt("-matload_block_size","Set the blocksize used to store the matrix","MatLoad",bs,&bs,PETSC_NULL);CHKERRQ(ierr);
2090   ierr = PetscOptionsEnd();CHKERRQ(ierr);
2091 
2092   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
2093   ierr = MPI_Comm_rank(comm,&rank);CHKERRQ(ierr);
2094   if (!rank) {
2095     ierr = PetscViewerBinaryGetDescriptor(viewer,&fd);CHKERRQ(ierr);
2096     ierr = PetscBinaryRead(fd,(char *)header,4,PETSC_INT);CHKERRQ(ierr);
2097     if (header[0] != MAT_FILE_COOKIE) SETERRQ(PETSC_ERR_FILE_UNEXPECTED,"not matrix object");
2098     if (header[3] < 0) {
2099       SETERRQ(PETSC_ERR_FILE_UNEXPECTED,"Matrix stored in special format, cannot load as MPISBAIJ");
2100     }
2101   }
2102 
2103   ierr = MPI_Bcast(header+1,3,MPIU_INT,0,comm);CHKERRQ(ierr);
2104   M = header[1]; N = header[2];
2105 
2106   if (M != N) SETERRQ(PETSC_ERR_SUP,"Can only do square matrices");
2107 
2108   /*
2109      This code adds extra rows to make sure the number of rows is
2110      divisible by the blocksize
2111   */
2112   Mbs        = M/bs;
2113   extra_rows = bs - M + bs*(Mbs);
2114   if (extra_rows == bs) extra_rows = 0;
2115   else                  Mbs++;
2116   if (extra_rows &&!rank) {
2117     ierr = PetscInfo(viewer,"Padding loaded matrix to match blocksize\n");CHKERRQ(ierr);
2118   }
2119 
2120   /* determine ownership of all rows */
2121   mbs        = Mbs/size + ((Mbs % size) > rank);
2122   m          = mbs*bs;
2123   ierr       = PetscMalloc(2*(size+2)*sizeof(PetscMPIInt),&rowners);CHKERRQ(ierr);
2124   browners   = rowners + size + 1;
2125   mmbs       = PetscMPIIntCast(mbs);
2126   ierr       = MPI_Allgather(&mmbs,1,MPI_INT,rowners+1,1,MPI_INT,comm);CHKERRQ(ierr);
2127   rowners[0] = 0;
2128   for (i=2; i<=size; i++) rowners[i] += rowners[i-1];
2129   for (i=0; i<=size;  i++) browners[i] = rowners[i]*bs;
2130   rstart = rowners[rank];
2131   rend   = rowners[rank+1];
2132 
2133   /* distribute row lengths to all processors */
2134   ierr = PetscMalloc((rend-rstart)*bs*sizeof(PetscMPIInt),&locrowlens);CHKERRQ(ierr);
2135   if (!rank) {
2136     ierr = PetscMalloc((M+extra_rows)*sizeof(PetscInt),&rowlengths);CHKERRQ(ierr);
2137     ierr = PetscBinaryRead(fd,rowlengths,M,PETSC_INT);CHKERRQ(ierr);
2138     for (i=0; i<extra_rows; i++) rowlengths[M+i] = 1;
2139     ierr = PetscMalloc(size*sizeof(PetscMPIInt),&sndcounts);CHKERRQ(ierr);
2140     for (i=0; i<size; i++) sndcounts[i] = browners[i+1] - browners[i];
2141     ierr = MPI_Scatterv(rowlengths,sndcounts,browners,MPIU_INT,locrowlens,(rend-rstart)*bs,MPIU_INT,0,comm);CHKERRQ(ierr);
2142     ierr = PetscFree(sndcounts);CHKERRQ(ierr);
2143   } else {
2144     ierr = MPI_Scatterv(0,0,0,MPIU_INT,locrowlens,(rend-rstart)*bs,MPIU_INT,0,comm);CHKERRQ(ierr);
2145   }
2146 
2147   if (!rank) {   /* procs[0] */
2148     /* calculate the number of nonzeros on each processor */
2149     ierr = PetscMalloc(size*sizeof(PetscInt),&procsnz);CHKERRQ(ierr);
2150     ierr = PetscMemzero(procsnz,size*sizeof(PetscInt));CHKERRQ(ierr);
2151     for (i=0; i<size; i++) {
2152       for (j=rowners[i]*bs; j< rowners[i+1]*bs; j++) {
2153         procsnz[i] += rowlengths[j];
2154       }
2155     }
2156     ierr = PetscFree(rowlengths);CHKERRQ(ierr);
2157 
2158     /* determine max buffer needed and allocate it */
2159     maxnz = 0;
2160     for (i=0; i<size; i++) {
2161       maxnz = PetscMax(maxnz,procsnz[i]);
2162     }
2163     ierr = PetscMalloc(maxnz*sizeof(PetscInt),&cols);CHKERRQ(ierr);
2164 
2165     /* read in my part of the matrix column indices  */
2166     nz     = procsnz[0];
2167     ierr   = PetscMalloc(nz*sizeof(PetscInt),&ibuf);CHKERRQ(ierr);
2168     mycols = ibuf;
2169     if (size == 1)  nz -= extra_rows;
2170     ierr = PetscBinaryRead(fd,mycols,nz,PETSC_INT);CHKERRQ(ierr);
2171     if (size == 1)  for (i=0; i< extra_rows; i++) { mycols[nz+i] = M+i; }
2172 
2173     /* read in every ones (except the last) and ship off */
2174     for (i=1; i<size-1; i++) {
2175       nz   = procsnz[i];
2176       ierr = PetscBinaryRead(fd,cols,nz,PETSC_INT);CHKERRQ(ierr);
2177       ierr = MPI_Send(cols,nz,MPIU_INT,i,tag,comm);CHKERRQ(ierr);
2178     }
2179     /* read in the stuff for the last proc */
2180     if (size != 1) {
2181       nz   = procsnz[size-1] - extra_rows;  /* the extra rows are not on the disk */
2182       ierr = PetscBinaryRead(fd,cols,nz,PETSC_INT);CHKERRQ(ierr);
2183       for (i=0; i<extra_rows; i++) cols[nz+i] = M+i;
2184       ierr = MPI_Send(cols,nz+extra_rows,MPIU_INT,size-1,tag,comm);CHKERRQ(ierr);
2185     }
2186     ierr = PetscFree(cols);CHKERRQ(ierr);
2187   } else {  /* procs[i], i>0 */
2188     /* determine buffer space needed for message */
2189     nz = 0;
2190     for (i=0; i<m; i++) {
2191       nz += locrowlens[i];
2192     }
2193     ierr   = PetscMalloc(nz*sizeof(PetscInt),&ibuf);CHKERRQ(ierr);
2194     mycols = ibuf;
2195     /* receive message of column indices*/
2196     ierr = MPI_Recv(mycols,nz,MPIU_INT,0,tag,comm,&status);CHKERRQ(ierr);
2197     ierr = MPI_Get_count(&status,MPIU_INT,&maxnz);CHKERRQ(ierr);
2198     if (maxnz != nz) SETERRQ(PETSC_ERR_FILE_UNEXPECTED,"something is wrong with file");
2199   }
2200 
2201   /* loop over local rows, determining number of off diagonal entries */
2202   ierr     = PetscMalloc(2*(rend-rstart+1)*sizeof(PetscInt),&dlens);CHKERRQ(ierr);
2203   odlens   = dlens + (rend-rstart);
2204   ierr     = PetscMalloc(3*Mbs*sizeof(PetscInt),&mask);CHKERRQ(ierr);
2205   ierr     = PetscMemzero(mask,3*Mbs*sizeof(PetscInt));CHKERRQ(ierr);
2206   masked1  = mask    + Mbs;
2207   masked2  = masked1 + Mbs;
2208   rowcount = 0; nzcount = 0;
2209   for (i=0; i<mbs; i++) {
2210     dcount  = 0;
2211     odcount = 0;
2212     for (j=0; j<bs; j++) {
2213       kmax = locrowlens[rowcount];
2214       for (k=0; k<kmax; k++) {
2215         tmp = mycols[nzcount++]/bs; /* block col. index */
2216         if (!mask[tmp]) {
2217           mask[tmp] = 1;
2218           if (tmp < rstart || tmp >= rend) masked2[odcount++] = tmp; /* entry in off-diag portion */
2219           else masked1[dcount++] = tmp; /* entry in diag portion */
2220         }
2221       }
2222       rowcount++;
2223     }
2224 
2225     dlens[i]  = dcount;  /* d_nzz[i] */
2226     odlens[i] = odcount; /* o_nzz[i] */
2227 
2228     /* zero out the mask elements we set */
2229     for (j=0; j<dcount; j++) mask[masked1[j]] = 0;
2230     for (j=0; j<odcount; j++) mask[masked2[j]] = 0;
2231   }
2232 
2233   /* create our matrix */
2234   ierr = MatCreate(comm,&A);CHKERRQ(ierr);
2235   ierr = MatSetSizes(A,m,m,PETSC_DETERMINE,PETSC_DETERMINE);CHKERRQ(ierr);
2236   ierr = MatSetType(A,type);CHKERRQ(ierr);
2237   ierr = MatMPISBAIJSetPreallocation(A,bs,0,dlens,0,odlens);CHKERRQ(ierr);
2238 
2239   if (!rank) {
2240     ierr = PetscMalloc(maxnz*sizeof(PetscScalar),&buf);CHKERRQ(ierr);
2241     /* read in my part of the matrix numerical values  */
2242     nz = procsnz[0];
2243     vals = buf;
2244     mycols = ibuf;
2245     if (size == 1)  nz -= extra_rows;
2246     ierr = PetscBinaryRead(fd,vals,nz,PETSC_SCALAR);CHKERRQ(ierr);
2247     if (size == 1)  for (i=0; i< extra_rows; i++) { vals[nz+i] = 1.0; }
2248 
2249     /* insert into matrix */
2250     jj      = rstart*bs;
2251     for (i=0; i<m; i++) {
2252       ierr = MatSetValues(A,1,&jj,locrowlens[i],mycols,vals,INSERT_VALUES);CHKERRQ(ierr);
2253       mycols += locrowlens[i];
2254       vals   += locrowlens[i];
2255       jj++;
2256     }
2257 
2258     /* read in other processors (except the last one) and ship out */
2259     for (i=1; i<size-1; i++) {
2260       nz   = procsnz[i];
2261       vals = buf;
2262       ierr = PetscBinaryRead(fd,vals,nz,PETSC_SCALAR);CHKERRQ(ierr);
2263       ierr = MPI_Send(vals,nz,MPIU_SCALAR,i,((PetscObject)A)->tag,comm);CHKERRQ(ierr);
2264     }
2265     /* the last proc */
2266     if (size != 1){
2267       nz   = procsnz[i] - extra_rows;
2268       vals = buf;
2269       ierr = PetscBinaryRead(fd,vals,nz,PETSC_SCALAR);CHKERRQ(ierr);
2270       for (i=0; i<extra_rows; i++) vals[nz+i] = 1.0;
2271       ierr = MPI_Send(vals,nz+extra_rows,MPIU_SCALAR,size-1,((PetscObject)A)->tag,comm);CHKERRQ(ierr);
2272     }
2273     ierr = PetscFree(procsnz);CHKERRQ(ierr);
2274 
2275   } else {
2276     /* receive numeric values */
2277     ierr = PetscMalloc(nz*sizeof(PetscScalar),&buf);CHKERRQ(ierr);
2278 
2279     /* receive message of values*/
2280     vals   = buf;
2281     mycols = ibuf;
2282     ierr   = MPI_Recv(vals,nz,MPIU_SCALAR,0,((PetscObject)A)->tag,comm,&status);CHKERRQ(ierr);
2283     ierr   = MPI_Get_count(&status,MPIU_SCALAR,&maxnz);CHKERRQ(ierr);
2284     if (maxnz != nz) SETERRQ(PETSC_ERR_FILE_UNEXPECTED,"something is wrong with file");
2285 
2286     /* insert into matrix */
2287     jj      = rstart*bs;
2288     for (i=0; i<m; i++) {
2289       ierr    = MatSetValues_MPISBAIJ(A,1,&jj,locrowlens[i],mycols,vals,INSERT_VALUES);CHKERRQ(ierr);
2290       mycols += locrowlens[i];
2291       vals   += locrowlens[i];
2292       jj++;
2293     }
2294   }
2295 
2296   ierr = PetscFree(locrowlens);CHKERRQ(ierr);
2297   ierr = PetscFree(buf);CHKERRQ(ierr);
2298   ierr = PetscFree(ibuf);CHKERRQ(ierr);
2299   ierr = PetscFree(rowners);CHKERRQ(ierr);
2300   ierr = PetscFree(dlens);CHKERRQ(ierr);
2301   ierr = PetscFree(mask);CHKERRQ(ierr);
2302   ierr = MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
2303   ierr = MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
2304   *newmat = A;
2305   PetscFunctionReturn(0);
2306 }
2307 
2308 #undef __FUNCT__
2309 #define __FUNCT__ "MatMPISBAIJSetHashTableFactor"
2310 /*XXXXX@
2311    MatMPISBAIJSetHashTableFactor - Sets the factor required to compute the size of the HashTable.
2312 
2313    Input Parameters:
2314 .  mat  - the matrix
2315 .  fact - factor
2316 
2317    Collective on Mat
2318 
2319    Level: advanced
2320 
2321   Notes:
2322    This can also be set by the command line option: -mat_use_hash_table fact
2323 
2324 .keywords: matrix, hashtable, factor, HT
2325 
2326 .seealso: MatSetOption()
2327 @XXXXX*/
2328 
2329 
2330 #undef __FUNCT__
2331 #define __FUNCT__ "MatGetRowMaxAbs_MPISBAIJ"
2332 PetscErrorCode MatGetRowMaxAbs_MPISBAIJ(Mat A,Vec v,PetscInt idx[])
2333 {
2334   Mat_MPISBAIJ   *a = (Mat_MPISBAIJ*)A->data;
2335   Mat_SeqBAIJ    *b = (Mat_SeqBAIJ*)(a->B)->data;
2336   PetscReal      atmp;
2337   PetscReal      *work,*svalues,*rvalues;
2338   PetscErrorCode ierr;
2339   PetscInt       i,bs,mbs,*bi,*bj,brow,j,ncols,krow,kcol,col,row,Mbs,bcol;
2340   PetscMPIInt    rank,size;
2341   PetscInt       *rowners_bs,dest,count,source;
2342   PetscScalar    *va;
2343   MatScalar      *ba;
2344   MPI_Status     stat;
2345 
2346   PetscFunctionBegin;
2347   if (idx) SETERRQ(PETSC_ERR_SUP,"Send email to petsc-maint@mcs.anl.gov");
2348   ierr = MatGetRowMaxAbs(a->A,v,PETSC_NULL);CHKERRQ(ierr);
2349   ierr = VecGetArray(v,&va);CHKERRQ(ierr);
2350 
2351   ierr = MPI_Comm_size(((PetscObject)A)->comm,&size);CHKERRQ(ierr);
2352   ierr = MPI_Comm_rank(((PetscObject)A)->comm,&rank);CHKERRQ(ierr);
2353 
2354   bs   = A->rmap.bs;
2355   mbs  = a->mbs;
2356   Mbs  = a->Mbs;
2357   ba   = b->a;
2358   bi   = b->i;
2359   bj   = b->j;
2360 
2361   /* find ownerships */
2362   rowners_bs = A->rmap.range;
2363 
2364   /* each proc creates an array to be distributed */
2365   ierr = PetscMalloc(bs*Mbs*sizeof(PetscReal),&work);CHKERRQ(ierr);
2366   ierr = PetscMemzero(work,bs*Mbs*sizeof(PetscReal));CHKERRQ(ierr);
2367 
2368   /* row_max for B */
2369   if (rank != size-1){
2370     for (i=0; i<mbs; i++) {
2371       ncols = bi[1] - bi[0]; bi++;
2372       brow  = bs*i;
2373       for (j=0; j<ncols; j++){
2374         bcol = bs*(*bj);
2375         for (kcol=0; kcol<bs; kcol++){
2376           col = bcol + kcol;                 /* local col index */
2377           col += rowners_bs[rank+1];      /* global col index */
2378           for (krow=0; krow<bs; krow++){
2379             atmp = PetscAbsScalar(*ba); ba++;
2380             row = brow + krow;    /* local row index */
2381             if (PetscRealPart(va[row]) < atmp) va[row] = atmp;
2382             if (work[col] < atmp) work[col] = atmp;
2383           }
2384         }
2385         bj++;
2386       }
2387     }
2388 
2389     /* send values to its owners */
2390     for (dest=rank+1; dest<size; dest++){
2391       svalues = work + rowners_bs[dest];
2392       count   = rowners_bs[dest+1]-rowners_bs[dest];
2393       ierr    = MPI_Send(svalues,count,MPIU_REAL,dest,rank,((PetscObject)A)->comm);CHKERRQ(ierr);
2394     }
2395   }
2396 
2397   /* receive values */
2398   if (rank){
2399     rvalues = work;
2400     count   = rowners_bs[rank+1]-rowners_bs[rank];
2401     for (source=0; source<rank; source++){
2402       ierr = MPI_Recv(rvalues,count,MPIU_REAL,MPI_ANY_SOURCE,MPI_ANY_TAG,((PetscObject)A)->comm,&stat);CHKERRQ(ierr);
2403       /* process values */
2404       for (i=0; i<count; i++){
2405         if (PetscRealPart(va[i]) < rvalues[i]) va[i] = rvalues[i];
2406       }
2407     }
2408   }
2409 
2410   ierr = VecRestoreArray(v,&va);CHKERRQ(ierr);
2411   ierr = PetscFree(work);CHKERRQ(ierr);
2412   PetscFunctionReturn(0);
2413 }
2414 
2415 #undef __FUNCT__
2416 #define __FUNCT__ "MatRelax_MPISBAIJ"
2417 PetscErrorCode MatRelax_MPISBAIJ(Mat matin,Vec bb,PetscReal omega,MatSORType flag,PetscReal fshift,PetscInt its,PetscInt lits,Vec xx)
2418 {
2419   Mat_MPISBAIJ   *mat = (Mat_MPISBAIJ*)matin->data;
2420   PetscErrorCode ierr;
2421   PetscInt       mbs=mat->mbs,bs=matin->rmap.bs;
2422   PetscScalar    *x,*b,*ptr,zero=0.0;
2423   Vec            bb1;
2424 
2425   PetscFunctionBegin;
2426   if (its <= 0 || lits <= 0) SETERRQ2(PETSC_ERR_ARG_WRONG,"Relaxation requires global its %D and local its %D both positive",its,lits);
2427   if (bs > 1)
2428     SETERRQ(PETSC_ERR_SUP,"SSOR for block size > 1 is not yet implemented");
2429 
2430   if ((flag & SOR_LOCAL_SYMMETRIC_SWEEP) == SOR_LOCAL_SYMMETRIC_SWEEP){
2431     if ( flag & SOR_ZERO_INITIAL_GUESS ) {
2432       ierr = (*mat->A->ops->relax)(mat->A,bb,omega,flag,fshift,lits,lits,xx);CHKERRQ(ierr);
2433       its--;
2434     }
2435 
2436     ierr = VecDuplicate(bb,&bb1);CHKERRQ(ierr);
2437     while (its--){
2438 
2439       /* lower triangular part: slvec0b = - B^T*xx */
2440       ierr = (*mat->B->ops->multtranspose)(mat->B,xx,mat->slvec0b);CHKERRQ(ierr);
2441 
2442       /* copy xx into slvec0a */
2443       ierr = VecGetArray(mat->slvec0,&ptr);CHKERRQ(ierr);
2444       ierr = VecGetArray(xx,&x);CHKERRQ(ierr);
2445       ierr = PetscMemcpy(ptr,x,bs*mbs*sizeof(MatScalar));CHKERRQ(ierr);
2446       ierr = VecRestoreArray(mat->slvec0,&ptr);CHKERRQ(ierr);
2447 
2448       ierr = VecScale(mat->slvec0,-1.0);CHKERRQ(ierr);
2449 
2450       /* copy bb into slvec1a */
2451       ierr = VecGetArray(mat->slvec1,&ptr);CHKERRQ(ierr);
2452       ierr = VecGetArray(bb,&b);CHKERRQ(ierr);
2453       ierr = PetscMemcpy(ptr,b,bs*mbs*sizeof(MatScalar));CHKERRQ(ierr);
2454       ierr = VecRestoreArray(mat->slvec1,&ptr);CHKERRQ(ierr);
2455 
2456       /* set slvec1b = 0 */
2457       ierr = VecSet(mat->slvec1b,zero);CHKERRQ(ierr);
2458 
2459       ierr = VecScatterBegin(mat->sMvctx,mat->slvec0,mat->slvec1,ADD_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
2460       ierr = VecRestoreArray(xx,&x);CHKERRQ(ierr);
2461       ierr = VecRestoreArray(bb,&b);CHKERRQ(ierr);
2462       ierr = VecScatterEnd(mat->sMvctx,mat->slvec0,mat->slvec1,ADD_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
2463 
2464       /* upper triangular part: bb1 = bb1 - B*x */
2465       ierr = (*mat->B->ops->multadd)(mat->B,mat->slvec1b,mat->slvec1a,bb1);CHKERRQ(ierr);
2466 
2467       /* local diagonal sweep */
2468       ierr = (*mat->A->ops->relax)(mat->A,bb1,omega,SOR_SYMMETRIC_SWEEP,fshift,lits,lits,xx);CHKERRQ(ierr);
2469     }
2470     ierr = VecDestroy(bb1);CHKERRQ(ierr);
2471   } else {
2472     SETERRQ(PETSC_ERR_SUP,"MatSORType is not supported for SBAIJ matrix format");
2473   }
2474   PetscFunctionReturn(0);
2475 }
2476 
2477 #undef __FUNCT__
2478 #define __FUNCT__ "MatRelax_MPISBAIJ_2comm"
2479 PetscErrorCode MatRelax_MPISBAIJ_2comm(Mat matin,Vec bb,PetscReal omega,MatSORType flag,PetscReal fshift,PetscInt its,PetscInt lits,Vec xx)
2480 {
2481   Mat_MPISBAIJ   *mat = (Mat_MPISBAIJ*)matin->data;
2482   PetscErrorCode ierr;
2483   Vec            lvec1,bb1;
2484 
2485   PetscFunctionBegin;
2486   if (its <= 0 || lits <= 0) SETERRQ2(PETSC_ERR_ARG_WRONG,"Relaxation requires global its %D and local its %D both positive",its,lits);
2487   if (matin->rmap.bs > 1)
2488     SETERRQ(PETSC_ERR_SUP,"SSOR for block size > 1 is not yet implemented");
2489 
2490   if ((flag & SOR_LOCAL_SYMMETRIC_SWEEP) == SOR_LOCAL_SYMMETRIC_SWEEP){
2491     if ( flag & SOR_ZERO_INITIAL_GUESS ) {
2492       ierr = (*mat->A->ops->relax)(mat->A,bb,omega,flag,fshift,lits,lits,xx);CHKERRQ(ierr);
2493       its--;
2494     }
2495 
2496     ierr = VecDuplicate(mat->lvec,&lvec1);CHKERRQ(ierr);
2497     ierr = VecDuplicate(bb,&bb1);CHKERRQ(ierr);
2498     while (its--){
2499       ierr = VecScatterBegin(mat->Mvctx,xx,mat->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
2500 
2501       /* lower diagonal part: bb1 = bb - B^T*xx */
2502       ierr = (*mat->B->ops->multtranspose)(mat->B,xx,lvec1);CHKERRQ(ierr);
2503       ierr = VecScale(lvec1,-1.0);CHKERRQ(ierr);
2504 
2505       ierr = VecScatterEnd(mat->Mvctx,xx,mat->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
2506       ierr = VecCopy(bb,bb1);CHKERRQ(ierr);
2507       ierr = VecScatterBegin(mat->Mvctx,lvec1,bb1,ADD_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
2508 
2509       /* upper diagonal part: bb1 = bb1 - B*x */
2510       ierr = VecScale(mat->lvec,-1.0);CHKERRQ(ierr);
2511       ierr = (*mat->B->ops->multadd)(mat->B,mat->lvec,bb1,bb1);CHKERRQ(ierr);
2512 
2513       ierr = VecScatterEnd(mat->Mvctx,lvec1,bb1,ADD_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
2514 
2515       /* diagonal sweep */
2516       ierr = (*mat->A->ops->relax)(mat->A,bb1,omega,SOR_SYMMETRIC_SWEEP,fshift,lits,lits,xx);CHKERRQ(ierr);
2517     }
2518     ierr = VecDestroy(lvec1);CHKERRQ(ierr);
2519     ierr = VecDestroy(bb1);CHKERRQ(ierr);
2520   } else {
2521     SETERRQ(PETSC_ERR_SUP,"MatSORType is not supported for SBAIJ matrix format");
2522   }
2523   PetscFunctionReturn(0);
2524 }
2525 
2526