xref: /petsc/src/mat/impls/sbaij/mpi/mpisbaij.c (revision 7843d17afa8c1ec0c9a03b3c2ea6d3e3db42e252)
1 /*$Id: mpisbaij.c,v 1.26 2000/10/10 20:46:03 hzhang Exp hzhang $*/
2 
3 #include "src/mat/impls/baij/mpi/mpibaij.h"    /*I "petscmat.h" I*/
4 #include "src/vec/vecimpl.h"
5 #include "mpisbaij.h"
6 #include "src/mat/impls/sbaij/seq/sbaij.h"
7 
8 extern int MatSetUpMultiply_MPISBAIJ(Mat);
9 extern int DisAssemble_MPISBAIJ(Mat);
10 extern int MatIncreaseOverlap_MPISBAIJ(Mat,int,IS *,int);
11 extern int MatGetSubMatrices_MPISBAIJ(Mat,int,IS *,IS *,MatReuse,Mat **);
12 extern int MatGetValues_SeqSBAIJ(Mat,int,int *,int,int *,Scalar *);
13 extern int MatSetValues_SeqSBAIJ(Mat,int,int *,int,int *,Scalar *,InsertMode);
14 extern int MatSetValuesBlocked_SeqSBAIJ(Mat,int,int*,int,int*,Scalar*,InsertMode);
15 extern int MatGetRow_SeqSBAIJ(Mat,int,int*,int**,Scalar**);
16 extern int MatRestoreRow_SeqSBAIJ(Mat,int,int*,int**,Scalar**);
17 extern int MatPrintHelp_SeqSBAIJ(Mat);
18 extern int MatZeroRows_SeqSBAIJ(Mat,IS,Scalar*);
19 extern int MatZeroRows_SeqBAIJ(Mat,IS,Scalar *);
20 extern int MatGetRowMax_MPISBAIJ(Mat,Vec);
21 
22 /*  UGLY, ugly, ugly
23    When MatScalar == Scalar the function MatSetValuesBlocked_MPIBAIJ_MatScalar() does
24    not exist. Otherwise ..._MatScalar() takes matrix elements in single precision and
25    inserts them into the single precision data structure. The function MatSetValuesBlocked_MPIBAIJ()
26    converts the entries into single precision and then calls ..._MatScalar() to put them
27    into the single precision data structures.
28 */
29 #if defined(PETSC_USE_MAT_SINGLE)
30 extern int MatSetValuesBlocked_SeqSBAIJ_MatScalar(Mat,int,int*,int,int*,MatScalar*,InsertMode);
31 extern int MatSetValues_MPISBAIJ_MatScalar(Mat,int,int*,int,int*,MatScalar*,InsertMode);
32 extern int MatSetValuesBlocked_MPISBAIJ_MatScalar(Mat,int,int*,int,int*,MatScalar*,InsertMode);
33 extern int MatSetValues_MPISBAIJ_HT_MatScalar(Mat,int,int*,int,int*,MatScalar*,InsertMode);
34 extern int MatSetValuesBlocked_MPISBAIJ_HT_MatScalar(Mat,int,int*,int,int*,MatScalar*,InsertMode);
35 #else
36 #define MatSetValuesBlocked_SeqSBAIJ_MatScalar      MatSetValuesBlocked_SeqSBAIJ
37 #define MatSetValues_MPISBAIJ_MatScalar             MatSetValues_MPISBAIJ
38 #define MatSetValuesBlocked_MPISBAIJ_MatScalar      MatSetValuesBlocked_MPISBAIJ
39 #define MatSetValues_MPISBAIJ_HT_MatScalar          MatSetValues_MPISBAIJ_HT
40 #define MatSetValuesBlocked_MPISBAIJ_HT_MatScalar   MatSetValuesBlocked_MPISBAIJ_HT
41 #endif
42 
43 EXTERN_C_BEGIN
44 #undef __FUNC__
45 #define __FUNC__ /*<a name="MatStoreValues_MPISBAIJ"></a>*/"MatStoreValues_MPISBAIJ"
46 int MatStoreValues_MPISBAIJ(Mat mat)
47 {
48   Mat_MPISBAIJ *aij = (Mat_MPISBAIJ *)mat->data;
49   int         ierr;
50 
51   PetscFunctionBegin;
52   ierr = MatStoreValues(aij->A);CHKERRQ(ierr);
53   ierr = MatStoreValues(aij->B);CHKERRQ(ierr);
54   PetscFunctionReturn(0);
55 }
56 EXTERN_C_END
57 
58 EXTERN_C_BEGIN
59 #undef __FUNC__
60 #define __FUNC__ /*<a name="MatRetrieveValues_MPISBAIJ"></a>*/"MatRetrieveValues_MPISBAIJ"
61 int MatRetrieveValues_MPISBAIJ(Mat mat)
62 {
63   Mat_MPISBAIJ *aij = (Mat_MPISBAIJ *)mat->data;
64   int         ierr;
65 
66   PetscFunctionBegin;
67   ierr = MatRetrieveValues(aij->A);CHKERRQ(ierr);
68   ierr = MatRetrieveValues(aij->B);CHKERRQ(ierr);
69   PetscFunctionReturn(0);
70 }
71 EXTERN_C_END
72 
73 /*
74      Local utility routine that creates a mapping from the global column
75    number to the local number in the off-diagonal part of the local
76    storage of the matrix.  This is done in a non scable way since the
77    length of colmap equals the global matrix length.
78 */
79 #undef __FUNC__
80 #define __FUNC__ /*<a name="CreateColmap_MPISBAIJ_Private"></a>*/"CreateColmap_MPISBAIJ_Private"
81 static int CreateColmap_MPISBAIJ_Private(Mat mat)
82 {
83   PetscFunctionBegin;
84   SETERRQ(1,"Function not yet written for SBAIJ format");
85   /* PetscFunctionReturn(0); */
86 }
87 
88 #define CHUNKSIZE  10
89 
90 #define  MatSetValues_SeqSBAIJ_A_Private(row,col,value,addv) \
91 { \
92  \
93     brow = row/bs;  \
94     rp   = aj + ai[brow]; ap = aa + bs2*ai[brow]; \
95     rmax = aimax[brow]; nrow = ailen[brow]; \
96       bcol = col/bs; \
97       ridx = row % bs; cidx = col % bs; \
98       low = 0; high = nrow; \
99       while (high-low > 3) { \
100         t = (low+high)/2; \
101         if (rp[t] > bcol) high = t; \
102         else              low  = t; \
103       } \
104       for (_i=low; _i<high; _i++) { \
105         if (rp[_i] > bcol) break; \
106         if (rp[_i] == bcol) { \
107           bap  = ap +  bs2*_i + bs*cidx + ridx; \
108           if (addv == ADD_VALUES) *bap += value;  \
109           else                    *bap  = value;  \
110           goto a_noinsert; \
111         } \
112       } \
113       if (a->nonew == 1) goto a_noinsert; \
114       else if (a->nonew == -1) SETERRQ(PETSC_ERR_ARG_OUTOFRANGE,"Inserting a new nonzero into matrix"); \
115       if (nrow >= rmax) { \
116         /* there is no extra room in row, therefore enlarge */ \
117         int       new_nz = ai[a->mbs] + CHUNKSIZE,len,*new_i,*new_j; \
118         MatScalar *new_a; \
119  \
120         if (a->nonew == -2) SETERRQ(PETSC_ERR_ARG_OUTOFRANGE,"Inserting a new nonzero in the matrix"); \
121  \
122         /* malloc new storage space */ \
123         len     = new_nz*(sizeof(int)+bs2*sizeof(MatScalar))+(a->mbs+1)*sizeof(int); \
124         new_a   = (MatScalar*)PetscMalloc(len);CHKPTRQ(new_a); \
125         new_j   = (int*)(new_a + bs2*new_nz); \
126         new_i   = new_j + new_nz; \
127  \
128         /* copy over old data into new slots */ \
129         for (ii=0; ii<brow+1; ii++) {new_i[ii] = ai[ii];} \
130         for (ii=brow+1; ii<a->mbs+1; ii++) {new_i[ii] = ai[ii]+CHUNKSIZE;} \
131         ierr = PetscMemcpy(new_j,aj,(ai[brow]+nrow)*sizeof(int));CHKERRQ(ierr); \
132         len = (new_nz - CHUNKSIZE - ai[brow] - nrow); \
133         ierr = PetscMemcpy(new_j+ai[brow]+nrow+CHUNKSIZE,aj+ai[brow]+nrow,len*sizeof(int));CHKERRQ(ierr); \
134         ierr = PetscMemcpy(new_a,aa,(ai[brow]+nrow)*bs2*sizeof(MatScalar));CHKERRQ(ierr); \
135         ierr = PetscMemzero(new_a+bs2*(ai[brow]+nrow),bs2*CHUNKSIZE*sizeof(Scalar));CHKERRQ(ierr); \
136         ierr = PetscMemcpy(new_a+bs2*(ai[brow]+nrow+CHUNKSIZE), \
137                     aa+bs2*(ai[brow]+nrow),bs2*len*sizeof(MatScalar));CHKERRQ(ierr);  \
138         /* free up old matrix storage */ \
139         ierr = PetscFree(a->a);CHKERRQ(ierr);  \
140         if (!a->singlemalloc) { \
141           ierr = PetscFree(a->i);CHKERRQ(ierr); \
142           ierr = PetscFree(a->j);CHKERRQ(ierr);\
143         } \
144         aa = a->a = new_a; ai = a->i = new_i; aj = a->j = new_j;  \
145         a->singlemalloc = PETSC_TRUE; \
146  \
147         rp   = aj + ai[brow]; ap = aa + bs2*ai[brow]; \
148         rmax = aimax[brow] = aimax[brow] + CHUNKSIZE; \
149         PLogObjectMemory(A,CHUNKSIZE*(sizeof(int) + bs2*sizeof(MatScalar))); \
150         a->s_maxnz += bs2*CHUNKSIZE; \
151         a->reallocs++; \
152         a->s_nz++; \
153       } \
154       N = nrow++ - 1;  \
155       /* shift up all the later entries in this row */ \
156       for (ii=N; ii>=_i; ii--) { \
157         rp[ii+1] = rp[ii]; \
158         ierr = PetscMemcpy(ap+bs2*(ii+1),ap+bs2*(ii),bs2*sizeof(MatScalar));CHKERRQ(ierr); \
159       } \
160       if (N>=_i) { ierr = PetscMemzero(ap+bs2*_i,bs2*sizeof(MatScalar));CHKERRQ(ierr); }  \
161       rp[_i]                      = bcol;  \
162       ap[bs2*_i + bs*cidx + ridx] = value;  \
163       a_noinsert:; \
164     ailen[brow] = nrow; \
165 }
166 #ifndef MatSetValues_SeqBAIJ_B_Private
167 #define  MatSetValues_SeqSBAIJ_B_Private(row,col,value,addv) \
168 { \
169     brow = row/bs;  \
170     rp   = bj + bi[brow]; ap = ba + bs2*bi[brow]; \
171     rmax = bimax[brow]; nrow = bilen[brow]; \
172       bcol = col/bs; \
173       ridx = row % bs; cidx = col % bs; \
174       low = 0; high = nrow; \
175       while (high-low > 3) { \
176         t = (low+high)/2; \
177         if (rp[t] > bcol) high = t; \
178         else              low  = t; \
179       } \
180       for (_i=low; _i<high; _i++) { \
181         if (rp[_i] > bcol) break; \
182         if (rp[_i] == bcol) { \
183           bap  = ap +  bs2*_i + bs*cidx + ridx; \
184           if (addv == ADD_VALUES) *bap += value;  \
185           else                    *bap  = value;  \
186           goto b_noinsert; \
187         } \
188       } \
189       if (b->nonew == 1) goto b_noinsert; \
190       else if (b->nonew == -1) SETERRQ(PETSC_ERR_ARG_OUTOFRANGE,"Inserting a new nonzero into matrix"); \
191       if (nrow >= rmax) { \
192         /* there is no extra room in row, therefore enlarge */ \
193         int       new_nz = bi[b->mbs] + CHUNKSIZE,len,*new_i,*new_j; \
194         MatScalar *new_a; \
195  \
196         if (b->nonew == -2) SETERRQ(PETSC_ERR_ARG_OUTOFRANGE,"Inserting a new nonzero in the matrix"); \
197  \
198         /* malloc new storage space */ \
199         len     = new_nz*(sizeof(int)+bs2*sizeof(MatScalar))+(b->mbs+1)*sizeof(int); \
200         new_a   = (MatScalar*)PetscMalloc(len);CHKPTRQ(new_a); \
201         new_j   = (int*)(new_a + bs2*new_nz); \
202         new_i   = new_j + new_nz; \
203  \
204         /* copy over old data into new slots */ \
205         for (ii=0; ii<brow+1; ii++) {new_i[ii] = bi[ii];} \
206         for (ii=brow+1; ii<b->mbs+1; ii++) {new_i[ii] = bi[ii]+CHUNKSIZE;} \
207         ierr = PetscMemcpy(new_j,bj,(bi[brow]+nrow)*sizeof(int));CHKERRQ(ierr); \
208         len  = (new_nz - CHUNKSIZE - bi[brow] - nrow); \
209         ierr = PetscMemcpy(new_j+bi[brow]+nrow+CHUNKSIZE,bj+bi[brow]+nrow,len*sizeof(int));CHKERRQ(ierr); \
210         ierr = PetscMemcpy(new_a,ba,(bi[brow]+nrow)*bs2*sizeof(MatScalar));CHKERRQ(ierr); \
211         ierr = PetscMemzero(new_a+bs2*(bi[brow]+nrow),bs2*CHUNKSIZE*sizeof(MatScalar));CHKERRQ(ierr); \
212         ierr = PetscMemcpy(new_a+bs2*(bi[brow]+nrow+CHUNKSIZE), \
213                     ba+bs2*(bi[brow]+nrow),bs2*len*sizeof(MatScalar));CHKERRQ(ierr);  \
214         /* free up old matrix storage */ \
215         ierr = PetscFree(b->a);CHKERRQ(ierr);  \
216         if (!b->singlemalloc) { \
217           ierr = PetscFree(b->i);CHKERRQ(ierr); \
218           ierr = PetscFree(b->j);CHKERRQ(ierr); \
219         } \
220         ba = b->a = new_a; bi = b->i = new_i; bj = b->j = new_j;  \
221         b->singlemalloc = PETSC_TRUE; \
222  \
223         rp   = bj + bi[brow]; ap = ba + bs2*bi[brow]; \
224         rmax = bimax[brow] = bimax[brow] + CHUNKSIZE; \
225         PLogObjectMemory(B,CHUNKSIZE*(sizeof(int) + bs2*sizeof(MatScalar))); \
226         b->maxnz += bs2*CHUNKSIZE; \
227         b->reallocs++; \
228         b->nz++; \
229       } \
230       N = nrow++ - 1;  \
231       /* shift up all the later entries in this row */ \
232       for (ii=N; ii>=_i; ii--) { \
233         rp[ii+1] = rp[ii]; \
234         ierr = PetscMemcpy(ap+bs2*(ii+1),ap+bs2*(ii),bs2*sizeof(MatScalar));CHKERRQ(ierr); \
235       } \
236       if (N>=_i) { ierr = PetscMemzero(ap+bs2*_i,bs2*sizeof(MatScalar));CHKERRQ(ierr);}  \
237       rp[_i]                      = bcol;  \
238       ap[bs2*_i + bs*cidx + ridx] = value;  \
239       b_noinsert:; \
240     bilen[brow] = nrow; \
241 }
242 #endif
243 
244 #if defined(PETSC_USE_MAT_SINGLE)
245 #undef __FUNC__
246 #define __FUNC__ /*<a name="MatSetValues_MPISBAIJ"></a>*/"MatSetValues_MPISBAIJ"
247 int MatSetValues_MPISBAIJ(Mat mat,int m,int *im,int n,int *in,Scalar *v,InsertMode addv)
248 {
249   Mat_MPISBAIJ *b = (Mat_MPISBAIJ*)mat->data;
250   int         ierr,i,N = m*n;
251   MatScalar   *vsingle;
252 
253   PetscFunctionBegin;
254   if (N > b->setvalueslen) {
255     if (b->setvaluescopy) {ierr = PetscFree(b->setvaluescopy);CHKERRQ(ierr);}
256     b->setvaluescopy = (MatScalar*)PetscMalloc(N*sizeof(MatScalar));CHKPTRQ(b->setvaluescopy);
257     b->setvalueslen  = N;
258   }
259   vsingle = b->setvaluescopy;
260 
261   for (i=0; i<N; i++) {
262     vsingle[i] = v[i];
263   }
264   ierr = MatSetValues_MPISBAIJ_MatScalar(mat,m,im,n,in,vsingle,addv);CHKERRQ(ierr);
265   PetscFunctionReturn(0);
266 }
267 
268 #undef __FUNC__
269 #define __FUNC__ /*<a name="MatSetValuesBlocked_MPISBAIJ"></a>*/"MatSetValuesBlocked_MPISBAIJ"
270 int MatSetValuesBlocked_MPISBAIJ(Mat mat,int m,int *im,int n,int *in,Scalar *v,InsertMode addv)
271 {
272   Mat_MPIBAIJ *b = (Mat_MPIBAIJ*)mat->data;
273   int         ierr,i,N = m*n*b->bs2;
274   MatScalar   *vsingle;
275 
276   PetscFunctionBegin;
277   if (N > b->setvalueslen) {
278     if (b->setvaluescopy) {ierr = PetscFree(b->setvaluescopy);CHKERRQ(ierr);}
279     b->setvaluescopy = (MatScalar*)PetscMalloc(N*sizeof(MatScalar));CHKPTRQ(b->setvaluescopy);
280     b->setvalueslen  = N;
281   }
282   vsingle = b->setvaluescopy;
283   for (i=0; i<N; i++) {
284     vsingle[i] = v[i];
285   }
286   ierr = MatSetValuesBlocked_MPISBAIJ_MatScalar(mat,m,im,n,in,vsingle,addv);CHKERRQ(ierr);
287   PetscFunctionReturn(0);
288 }
289 
290 #undef __FUNC__
291 #define __FUNC__ /*<a name="MatSetValues_MPISBAIJ_HT"></a>*/"MatSetValues_MPISBAIJ_HT"
292 int MatSetValues_MPISBAIJ_HT(Mat mat,int m,int *im,int n,int *in,Scalar *v,InsertMode addv)
293 {
294   Mat_MPIBAIJ *b = (Mat_MPIBAIJ*)mat->data;
295   int         ierr,i,N = m*n;
296   MatScalar   *vsingle;
297 
298   PetscFunctionBegin;
299   SETERRQ(1,"Function not yet written for SBAIJ format");
300   /* PetscFunctionReturn(0); */
301 }
302 
303 #undef __FUNC__
304 #define __FUNC__ /*<a name="MatSetValuesBlocked_MPISBAIJ_HT"></a>*/"MatSetValuesBlocked_MPISBAIJ_HT"
305 int MatSetValuesBlocked_MPISBAIJ_HT(Mat mat,int m,int *im,int n,int *in,Scalar *v,InsertMode addv)
306 {
307   Mat_MPIBAIJ *b = (Mat_MPIBAIJ*)mat->data;
308   int         ierr,i,N = m*n*b->bs2;
309   MatScalar   *vsingle;
310 
311   PetscFunctionBegin;
312   SETERRQ(1,"Function not yet written for SBAIJ format");
313   /* PetscFunctionReturn(0); */
314 }
315 #endif
316 
317 /* Only add/insert a(i,j) with i<=j (blocks).
318    Any a(i,j) with i>j input by user is ingored.
319 */
320 #undef __FUNC__
321 #define __FUNC__ /*<a name="MatSetValues_MPIBAIJ"></a>*/"MatSetValues_MPIBAIJ"
322 int MatSetValues_MPISBAIJ_MatScalar(Mat mat,int m,int *im,int n,int *in,MatScalar *v,InsertMode addv)
323 {
324   Mat_MPISBAIJ *baij = (Mat_MPISBAIJ*)mat->data;
325   MatScalar   value;
326   int         ierr,i,j,row,col;
327   int         roworiented = baij->roworiented,rstart_orig=baij->rstart_bs ;
328   int         rend_orig=baij->rend_bs,cstart_orig=baij->cstart_bs;
329   int         cend_orig=baij->cend_bs,bs=baij->bs;
330 
331   /* Some Variables required in the macro */
332   Mat         A = baij->A;
333   Mat_SeqSBAIJ *a = (Mat_SeqSBAIJ*)(A)->data;
334   int         *aimax=a->imax,*ai=a->i,*ailen=a->ilen,*aj=a->j;
335   MatScalar   *aa=a->a;
336 
337   Mat         B = baij->B;
338   Mat_SeqBAIJ *b = (Mat_SeqBAIJ*)(B)->data;
339   int         *bimax=b->imax,*bi=b->i,*bilen=b->ilen,*bj=b->j;
340   MatScalar   *ba=b->a;
341 
342   int         *rp,ii,nrow,_i,rmax,N,brow,bcol;
343   int         low,high,t,ridx,cidx,bs2=a->bs2;
344   MatScalar   *ap,*bap;
345 
346   /* for stash */
347   int         n_loc, *in_loc=0;
348   MatScalar   *v_loc=0;
349 
350   PetscFunctionBegin;
351 
352   if(!baij->donotstash){
353     in_loc = (int*)PetscMalloc(n*sizeof(int));CHKPTRQ(in_loc);
354     v_loc  = (MatScalar*)PetscMalloc(n*sizeof(MatScalar));CHKPTRQ(v_loc);
355   }
356 
357   for (i=0; i<m; i++) {
358     if (im[i] < 0) continue;
359 #if defined(PETSC_USE_BOPT_g)
360     if (im[i] >= baij->M) SETERRQ(PETSC_ERR_ARG_OUTOFRANGE,"Row too large");
361 #endif
362     if (im[i] >= rstart_orig && im[i] < rend_orig) { /* this processor entry */
363       row = im[i] - rstart_orig;              /* local row index */
364       for (j=0; j<n; j++) {
365         if (im[i]/bs > in[j]/bs) continue;    /* ignore lower triangular blocks */
366         if (in[j] >= cstart_orig && in[j] < cend_orig){  /* diag entry (A) */
367           col = in[j] - cstart_orig;          /* local col index */
368           brow = row/bs; bcol = col/bs;
369           if (brow > bcol) continue;  /* ignore lower triangular blocks of A */
370           if (roworiented) value = v[i*n+j]; else value = v[i+j*m];
371           MatSetValues_SeqSBAIJ_A_Private(row,col,value,addv);
372           /* ierr = MatSetValues_SeqBAIJ(baij->A,1,&row,1,&col,&value,addv);CHKERRQ(ierr); */
373         } else if (in[j] < 0) continue;
374 #if defined(PETSC_USE_BOPT_g)
375         else if (in[j] >= baij->N) {SETERRQ(PETSC_ERR_ARG_OUTOFRANGE,"Col too large");}
376 #endif
377         else {  /* off-diag entry (B) */
378           if (mat->was_assembled) {
379             if (!baij->colmap) {
380               ierr = CreateColmap_MPISBAIJ_Private(mat);CHKERRQ(ierr);
381             }
382 #if defined (PETSC_USE_CTABLE)
383             ierr = PetscTableFind(baij->colmap,in[j]/bs + 1,&col);CHKERRQ(ierr);
384             col  = col - 1 + in[j]%bs;
385 #else
386             col = baij->colmap[in[j]/bs] - 1 + in[j]%bs;
387 #endif
388             if (col < 0 && !((Mat_SeqSBAIJ*)(baij->A->data))->nonew) {
389               ierr = DisAssemble_MPISBAIJ(mat);CHKERRQ(ierr);
390               col =  in[j];
391               /* Reinitialize the variables required by MatSetValues_SeqBAIJ_B_Private() */
392               B = baij->B;
393               b = (Mat_SeqBAIJ*)(B)->data;
394               bimax=b->imax;bi=b->i;bilen=b->ilen;bj=b->j;
395               ba=b->a;
396             }
397           } else col = in[j];
398           if (roworiented) value = v[i*n+j]; else value = v[i+j*m];
399           MatSetValues_SeqSBAIJ_B_Private(row,col,value,addv);
400           /* ierr = MatSetValues_SeqBAIJ(baij->B,1,&row,1,&col,&value,addv);CHKERRQ(ierr); */
401         }
402       }
403     } else {  /* off processor entry */
404       if (!baij->donotstash) {
405         n_loc = 0;
406         for (j=0; j<n; j++){
407           if (im[i]/bs > in[j]/bs) continue; /* ignore lower triangular blocks */
408           in_loc[n_loc] = in[j];
409           if (roworiented) {
410             v_loc[n_loc] = v[i*n+j];
411           } else {
412             v_loc[n_loc] = v[j*m+i];
413           }
414           n_loc++;
415         }
416         ierr = MatStashValuesRow_Private(&mat->stash,im[i],n_loc,in_loc,v_loc);CHKERRQ(ierr);
417       }
418     }
419   }
420 
421   if(!baij->donotstash){
422     ierr = PetscFree(in_loc);CHKERRQ(ierr);
423     ierr = PetscFree(v_loc);CHKERRQ(ierr);
424   }
425   PetscFunctionReturn(0);
426 }
427 
428 #undef __FUNC__
429 #define __FUNC__ /*<a name="MatSetValuesBlocked_MPISBAIJ"></a>*/"MatSetValuesBlocked_MPISBAIJ"
430 int MatSetValuesBlocked_MPISBAIJ_MatScalar(Mat mat,int m,int *im,int n,int *in,MatScalar *v,InsertMode addv)
431 {
432   PetscFunctionBegin;
433   SETERRQ(1,"Function not yet written for SBAIJ format");
434   /* PetscFunctionReturn(0); */
435 }
436 
437 #define HASH_KEY 0.6180339887
438 #define HASH(size,key,tmp) (tmp = (key)*HASH_KEY,(int)((size)*(tmp-(int)tmp)))
439 /* #define HASH(size,key) ((int)((size)*fmod(((key)*HASH_KEY),1))) */
440 /* #define HASH(size,key,tmp) ((int)((size)*fmod(((key)*HASH_KEY),1))) */
441 #undef __FUNC__
442 #define __FUNC__ /*<a name="MatSetValues_MPISBAIJ_HT_MatScalar"></a>*/"MatSetValues_MPISBAIJ_HT_MatScalar"
443 int MatSetValues_MPISBAIJ_HT_MatScalar(Mat mat,int m,int *im,int n,int *in,MatScalar *v,InsertMode addv)
444 {
445   PetscFunctionBegin;
446   SETERRQ(1,"Function not yet written for SBAIJ format");
447   /* PetscFunctionReturn(0); */
448 }
449 
450 #undef __FUNC__
451 #define __FUNC__ /*<a name=""></a>*/"MatSetValuesBlocked_MPISBAIJ_HT_MatScalar"
452 int MatSetValuesBlocked_MPISBAIJ_HT_MatScalar(Mat mat,int m,int *im,int n,int *in,MatScalar *v,InsertMode addv)
453 {
454   PetscFunctionBegin;
455   SETERRQ(1,"Function not yet written for SBAIJ format");
456   /* PetscFunctionReturn(0); */
457 }
458 
459 #undef __FUNC__
460 #define __FUNC__ /*<a name=""></a>*/"MatGetValues_MPISBAIJ"
461 int MatGetValues_MPISBAIJ(Mat mat,int m,int *idxm,int n,int *idxn,Scalar *v)
462 {
463   Mat_MPISBAIJ *baij = (Mat_MPISBAIJ*)mat->data;
464   int        bs=baij->bs,ierr,i,j,bsrstart = baij->rstart*bs,bsrend = baij->rend*bs;
465   int        bscstart = baij->cstart*bs,bscend = baij->cend*bs,row,col,data;
466 
467   PetscFunctionBegin;
468   for (i=0; i<m; i++) {
469     if (idxm[i] < 0) SETERRQ(PETSC_ERR_ARG_OUTOFRANGE,"Negative row");
470     if (idxm[i] >= baij->M) SETERRQ(PETSC_ERR_ARG_OUTOFRANGE,"Row too large");
471     if (idxm[i] >= bsrstart && idxm[i] < bsrend) {
472       row = idxm[i] - bsrstart;
473       for (j=0; j<n; j++) {
474         if (idxn[j] < 0) SETERRQ(PETSC_ERR_ARG_OUTOFRANGE,"Negative column");
475         if (idxn[j] >= baij->N) SETERRQ(PETSC_ERR_ARG_OUTOFRANGE,"Column too large");
476         if (idxn[j] >= bscstart && idxn[j] < bscend){
477           col = idxn[j] - bscstart;
478           ierr = MatGetValues_SeqSBAIJ(baij->A,1,&row,1,&col,v+i*n+j);CHKERRQ(ierr);
479         } else {
480           if (!baij->colmap) {
481             ierr = CreateColmap_MPISBAIJ_Private(mat);CHKERRQ(ierr);
482           }
483 #if defined (PETSC_USE_CTABLE)
484           ierr = PetscTableFind(baij->colmap,idxn[j]/bs+1,&data);CHKERRQ(ierr);
485           data --;
486 #else
487           data = baij->colmap[idxn[j]/bs]-1;
488 #endif
489           if((data < 0) || (baij->garray[data/bs] != idxn[j]/bs)) *(v+i*n+j) = 0.0;
490           else {
491             col  = data + idxn[j]%bs;
492             ierr = MatGetValues_SeqSBAIJ(baij->B,1,&row,1,&col,v+i*n+j);CHKERRQ(ierr);
493           }
494         }
495       }
496     } else {
497       SETERRQ(PETSC_ERR_SUP,"Only local values currently supported");
498     }
499   }
500  PetscFunctionReturn(0);
501 }
502 
503 #undef __FUNC__
504 #define __FUNC__ /*<a name=""></a>*/"MatNorm_MPISBAIJ"
505 int MatNorm_MPISBAIJ(Mat mat,NormType type,PetscReal *norm)
506 {
507   Mat_MPISBAIJ *baij = (Mat_MPISBAIJ*)mat->data;
508   /* Mat_SeqSBAIJ *amat = (Mat_SeqSBAIJ*)baij->A->data; */
509   /* Mat_SeqBAIJ  *bmat = (Mat_SeqBAIJ*)baij->B->data; */
510   int        ierr;
511   PetscReal  sum[2],*lnorm2;
512 
513   PetscFunctionBegin;
514   if (baij->size == 1) {
515     ierr =  MatNorm(baij->A,type,norm);CHKERRQ(ierr);
516   } else {
517     if (type == NORM_FROBENIUS) {
518       lnorm2 = (double*)PetscMalloc(2*sizeof(double));CHKPTRQ(lnorm2);
519       ierr =  MatNorm(baij->A,type,lnorm2);CHKERRQ(ierr);
520       *lnorm2 = (*lnorm2)*(*lnorm2); lnorm2++;            /* squar power of norm(A) */
521       ierr =  MatNorm(baij->B,type,lnorm2);CHKERRQ(ierr);
522       *lnorm2 = (*lnorm2)*(*lnorm2); lnorm2--;             /* squar power of norm(B) */
523       /*
524       ierr = MPI_Comm_rank(PETSC_COMM_WORLD,&rank);CHKERRQ(ierr);
525       PetscSynchronizedPrintf(PETSC_COMM_WORLD,"[%d], lnorm2=%g, %g\n",rank,lnorm2[0],lnorm2[1]);
526       */
527       ierr = MPI_Allreduce(lnorm2,&sum,2,MPI_DOUBLE,MPI_SUM,mat->comm);CHKERRQ(ierr);
528       /*
529       PetscSynchronizedPrintf(PETSC_COMM_WORLD,"[%d], sum=%g, %g\n",rank,sum[0],sum[1]);
530       PetscSynchronizedFlush(PETSC_COMM_WORLD); */
531 
532       *norm = sqrt(sum[0] + 2*sum[1]);
533       ierr = PetscFree(lnorm2);CHKERRQ(ierr);
534     } else {
535       SETERRQ(PETSC_ERR_SUP,"No support for this norm yet");
536     }
537   }
538   PetscFunctionReturn(0);
539 }
540 
541 /*
542   Creates the hash table, and sets the table
543   This table is created only once.
544   If new entried need to be added to the matrix
545   then the hash table has to be destroyed and
546   recreated.
547 */
548 #undef __FUNC__
549 #define __FUNC__ /*<a name=""></a>*/"MatCreateHashTable_MPISBAIJ_Private"
550 int MatCreateHashTable_MPISBAIJ_Private(Mat mat,PetscReal factor)
551 {
552   PetscFunctionBegin;
553   SETERRQ(1,"Function not yet written for SBAIJ format");
554   /* PetscFunctionReturn(0); */
555 }
556 
557 #undef __FUNC__
558 #define __FUNC__ /*<a name=""></a>*/"MatAssemblyBegin_MPISBAIJ"
559 int MatAssemblyBegin_MPISBAIJ(Mat mat,MatAssemblyType mode)
560 {
561   Mat_MPISBAIJ *baij = (Mat_MPISBAIJ*)mat->data;
562   int         ierr,nstash,reallocs;
563   InsertMode  addv;
564 
565   PetscFunctionBegin;
566   if (baij->donotstash) {
567     PetscFunctionReturn(0);
568   }
569 
570   /* make sure all processors are either in INSERTMODE or ADDMODE */
571   ierr = MPI_Allreduce(&mat->insertmode,&addv,1,MPI_INT,MPI_BOR,mat->comm);CHKERRQ(ierr);
572   if (addv == (ADD_VALUES|INSERT_VALUES)) {
573     SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Some processors inserted others added");
574   }
575   mat->insertmode = addv; /* in case this processor had no cache */
576 
577   ierr = MatStashScatterBegin_Private(&mat->stash,baij->rowners_bs);CHKERRQ(ierr);
578   ierr = MatStashScatterBegin_Private(&mat->bstash,baij->rowners);CHKERRQ(ierr);
579   ierr = MatStashGetInfo_Private(&mat->stash,&nstash,&reallocs);CHKERRQ(ierr);
580   PLogInfo(0,"MatAssemblyBegin_MPISBAIJ:Stash has %d entries,uses %d mallocs.\n",nstash,reallocs);
581   ierr = MatStashGetInfo_Private(&mat->stash,&nstash,&reallocs);CHKERRQ(ierr);
582   PLogInfo(0,"MatAssemblyBegin_MPISBAIJ:Block-Stash has %d entries, uses %d mallocs.\n",nstash,reallocs);
583   PetscFunctionReturn(0);
584 }
585 
586 #undef __FUNC__
587 #define __FUNC__ /*<a name=""></a>*/"MatAssemblyEnd_MPISBAIJ"
588 int MatAssemblyEnd_MPISBAIJ(Mat mat,MatAssemblyType mode)
589 {
590   Mat_MPISBAIJ *baij=(Mat_MPISBAIJ*)mat->data;
591   Mat_SeqSBAIJ  *a=(Mat_SeqSBAIJ*)baij->A->data;
592   Mat_SeqBAIJ  *b=(Mat_SeqBAIJ*)baij->B->data;
593   int         i,j,rstart,ncols,n,ierr,flg,bs2=baij->bs2;
594   int         *row,*col,other_disassembled;
595   PetscTruth  r1,r2,r3;
596   MatScalar   *val;
597   InsertMode  addv = mat->insertmode;
598   int         rank;
599 
600   PetscFunctionBegin;
601   /* remove 2 line below later */
602   ierr = MPI_Comm_rank(PETSC_COMM_WORLD, &rank);CHKERRQ(ierr);
603 
604   if (!baij->donotstash) {
605     while (1) {
606       ierr = MatStashScatterGetMesg_Private(&mat->stash,&n,&row,&col,&val,&flg);CHKERRQ(ierr);
607       /*
608       PetscSynchronizedPrintf(PETSC_COMM_WORLD,"[%d]: in AssemblyEnd, stash, flg=%d\n",rank,flg);
609       PetscSynchronizedFlush(PETSC_COMM_WORLD);
610       */
611       if (!flg) break;
612 
613       for (i=0; i<n;) {
614         /* Now identify the consecutive vals belonging to the same row */
615         for (j=i,rstart=row[j]; j<n; j++) { if (row[j] != rstart) break; }
616         if (j < n) ncols = j-i;
617         else       ncols = n-i;
618         /* Now assemble all these values with a single function call */
619         ierr = MatSetValues_MPISBAIJ_MatScalar(mat,1,row+i,ncols,col+i,val+i,addv);CHKERRQ(ierr);
620         i = j;
621       }
622     }
623     ierr = MatStashScatterEnd_Private(&mat->stash);CHKERRQ(ierr);
624     /* Now process the block-stash. Since the values are stashed column-oriented,
625        set the roworiented flag to column oriented, and after MatSetValues()
626        restore the original flags */
627     r1 = baij->roworiented;
628     r2 = a->roworiented;
629     r3 = b->roworiented;
630     baij->roworiented = PETSC_FALSE;
631     a->roworiented    = PETSC_FALSE;
632     b->roworiented    = PETSC_FALSE;
633     while (1) {
634       ierr = MatStashScatterGetMesg_Private(&mat->bstash,&n,&row,&col,&val,&flg);CHKERRQ(ierr);
635       if (!flg) break;
636 
637       for (i=0; i<n;) {
638         /* Now identify the consecutive vals belonging to the same row */
639         for (j=i,rstart=row[j]; j<n; j++) { if (row[j] != rstart) break; }
640         if (j < n) ncols = j-i;
641         else       ncols = n-i;
642         ierr = MatSetValuesBlocked_MPISBAIJ_MatScalar(mat,1,row+i,ncols,col+i,val+i*bs2,addv);CHKERRQ(ierr);
643         i = j;
644       }
645     }
646     ierr = MatStashScatterEnd_Private(&mat->bstash);CHKERRQ(ierr);
647     baij->roworiented = r1;
648     a->roworiented    = r2;
649     b->roworiented    = r3;
650   }
651 
652   ierr = MatAssemblyBegin(baij->A,mode);CHKERRQ(ierr);
653   ierr = MatAssemblyEnd(baij->A,mode);CHKERRQ(ierr);
654 
655   /* determine if any processor has disassembled, if so we must
656      also disassemble ourselfs, in order that we may reassemble. */
657   /*
658      if nonzero structure of submatrix B cannot change then we know that
659      no processor disassembled thus we can skip this stuff
660   */
661   if (!((Mat_SeqBAIJ*)baij->B->data)->nonew)  {
662     ierr = MPI_Allreduce(&mat->was_assembled,&other_disassembled,1,MPI_INT,MPI_PROD,mat->comm);CHKERRQ(ierr);
663     if (mat->was_assembled && !other_disassembled) {
664       ierr = DisAssemble_MPISBAIJ(mat);CHKERRQ(ierr);
665     }
666   }
667 
668   if (!mat->was_assembled && mode == MAT_FINAL_ASSEMBLY) {
669     ierr = MatSetUpMultiply_MPISBAIJ(mat);CHKERRQ(ierr);
670   }
671   ierr = MatAssemblyBegin(baij->B,mode);CHKERRQ(ierr);
672   ierr = MatAssemblyEnd(baij->B,mode);CHKERRQ(ierr);
673 
674 #if defined(PETSC_USE_BOPT_g)
675   if (baij->ht && mode== MAT_FINAL_ASSEMBLY) {
676     PLogInfo(0,"MatAssemblyEnd_MPISBAIJ:Average Hash Table Search in MatSetValues = %5.2f\n",((double)baij->ht_total_ct)/baij->ht_insert_ct);
677     baij->ht_total_ct  = 0;
678     baij->ht_insert_ct = 0;
679   }
680 #endif
681   if (baij->ht_flag && !baij->ht && mode == MAT_FINAL_ASSEMBLY) {
682     ierr = MatCreateHashTable_MPISBAIJ_Private(mat,baij->ht_fact);CHKERRQ(ierr);
683     mat->ops->setvalues        = MatSetValues_MPISBAIJ_HT;
684     mat->ops->setvaluesblocked = MatSetValuesBlocked_MPISBAIJ_HT;
685   }
686 
687   if (baij->rowvalues) {
688     ierr = PetscFree(baij->rowvalues);CHKERRQ(ierr);
689     baij->rowvalues = 0;
690   }
691   PetscFunctionReturn(0);
692 }
693 
694 #undef __FUNC__
695 #define __FUNC__ /*<a name=""></a>*/"MatView_MPISBAIJ_ASCIIorDraworSocket"
696 static int MatView_MPISBAIJ_ASCIIorDraworSocket(Mat mat,Viewer viewer)
697 {
698   Mat_MPISBAIJ  *baij = (Mat_MPISBAIJ*)mat->data;
699   int          ierr,format,bs = baij->bs,size = baij->size,rank = baij->rank;
700   PetscTruth   isascii,isdraw;
701   Viewer       sviewer;
702 
703   PetscFunctionBegin;
704   ierr = PetscTypeCompare((PetscObject)viewer,ASCII_VIEWER,&isascii);CHKERRQ(ierr);
705   ierr = PetscTypeCompare((PetscObject)viewer,DRAW_VIEWER,&isdraw);CHKERRQ(ierr);
706   if (isascii) {
707     ierr = ViewerGetFormat(viewer,&format);CHKERRQ(ierr);
708     if (format == VIEWER_FORMAT_ASCII_INFO_LONG) {
709       MatInfo info;
710       ierr = MPI_Comm_rank(mat->comm,&rank);CHKERRQ(ierr);
711       ierr = MatGetInfo(mat,MAT_LOCAL,&info);CHKERRQ(ierr);
712       ierr = ViewerASCIISynchronizedPrintf(viewer,"[%d] Local rows %d nz %d nz alloced %d bs %d mem %d\n",
713               rank,baij->m,(int)info.nz_used*bs,(int)info.nz_allocated*bs,
714               baij->bs,(int)info.memory);CHKERRQ(ierr);
715       ierr = MatGetInfo(baij->A,MAT_LOCAL,&info);CHKERRQ(ierr);
716       ierr = ViewerASCIISynchronizedPrintf(viewer,"[%d] on-diagonal part: nz %d \n",rank,(int)info.nz_used*bs);CHKERRQ(ierr);
717       ierr = MatGetInfo(baij->B,MAT_LOCAL,&info);CHKERRQ(ierr);
718       ierr = ViewerASCIISynchronizedPrintf(viewer,"[%d] off-diagonal part: nz %d \n",rank,(int)info.nz_used*bs);CHKERRQ(ierr);
719       ierr = ViewerFlush(viewer);CHKERRQ(ierr);
720       ierr = VecScatterView(baij->Mvctx,viewer);CHKERRQ(ierr);
721       PetscFunctionReturn(0);
722     } else if (format == VIEWER_FORMAT_ASCII_INFO) {
723       ierr = ViewerASCIIPrintf(viewer,"  block size is %d\n",bs);CHKERRQ(ierr);
724       PetscFunctionReturn(0);
725     }
726   }
727 
728   if (isdraw) {
729     Draw       draw;
730     PetscTruth isnull;
731     ierr = ViewerDrawGetDraw(viewer,0,&draw);CHKERRQ(ierr);
732     ierr = DrawIsNull(draw,&isnull);CHKERRQ(ierr); if (isnull) PetscFunctionReturn(0);
733   }
734 
735   if (size == 1) {
736     ierr = MatView(baij->A,viewer);CHKERRQ(ierr);
737   } else {
738     /* assemble the entire matrix onto first processor. */
739     Mat         A;
740     Mat_SeqSBAIJ *Aloc;
741     Mat_SeqBAIJ *Bloc;
742     int         M = baij->M,N = baij->N,*ai,*aj,col,i,j,k,*rvals,mbs = baij->mbs;
743     MatScalar   *a;
744 
745     if (!rank) {
746       ierr = MatCreateMPISBAIJ(mat->comm,baij->bs,M,N,M,N,0,PETSC_NULL,0,PETSC_NULL,&A);CHKERRQ(ierr);
747     } else {
748       ierr = MatCreateMPISBAIJ(mat->comm,baij->bs,0,0,M,N,0,PETSC_NULL,0,PETSC_NULL,&A);CHKERRQ(ierr);
749     }
750     PLogObjectParent(mat,A);
751 
752     /* copy over the A part */
753     Aloc  = (Mat_SeqSBAIJ*)baij->A->data;
754     ai    = Aloc->i; aj = Aloc->j; a = Aloc->a;
755     rvals = (int*)PetscMalloc(bs*sizeof(int));CHKPTRQ(rvals);
756 
757     for (i=0; i<mbs; i++) {
758       rvals[0] = bs*(baij->rstart + i);
759       for (j=1; j<bs; j++) { rvals[j] = rvals[j-1] + 1; }
760       for (j=ai[i]; j<ai[i+1]; j++) {
761         col = (baij->cstart+aj[j])*bs;
762         for (k=0; k<bs; k++) {
763           ierr = MatSetValues_MPISBAIJ_MatScalar(A,bs,rvals,1,&col,a,INSERT_VALUES);CHKERRQ(ierr);
764           col++; a += bs;
765         }
766       }
767     }
768     /* copy over the B part */
769     Bloc = (Mat_SeqBAIJ*)baij->B->data;
770     ai = Bloc->i; aj = Bloc->j; a = Bloc->a;
771     for (i=0; i<mbs; i++) {
772       rvals[0] = bs*(baij->rstart + i);
773       for (j=1; j<bs; j++) { rvals[j] = rvals[j-1] + 1; }
774       for (j=ai[i]; j<ai[i+1]; j++) {
775         col = baij->garray[aj[j]]*bs;
776         for (k=0; k<bs; k++) {
777           ierr = MatSetValues_MPISBAIJ_MatScalar(A,bs,rvals,1,&col,a,INSERT_VALUES);CHKERRQ(ierr);
778           col++; a += bs;
779         }
780       }
781     }
782     ierr = PetscFree(rvals);CHKERRQ(ierr);
783     ierr = MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
784     ierr = MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
785     /*
786        Everyone has to call to draw the matrix since the graphics waits are
787        synchronized across all processors that share the Draw object
788     */
789     ierr = ViewerGetSingleton(viewer,&sviewer);CHKERRQ(ierr);
790     if (!rank) {
791       ierr = MatView(((Mat_MPISBAIJ*)(A->data))->A,sviewer);CHKERRQ(ierr);
792     }
793     ierr = ViewerRestoreSingleton(viewer,&sviewer);CHKERRQ(ierr);
794     ierr = MatDestroy(A);CHKERRQ(ierr);
795   }
796   PetscFunctionReturn(0);
797 }
798 
799 #undef __FUNC__
800 #define __FUNC__ /*<a name=""></a>*/"MatView_MPISBAIJ"
801 int MatView_MPISBAIJ(Mat mat,Viewer viewer)
802 {
803   int        ierr;
804   PetscTruth isascii,isdraw,issocket,isbinary;
805 
806   PetscFunctionBegin;
807   ierr = PetscTypeCompare((PetscObject)viewer,ASCII_VIEWER,&isascii);CHKERRQ(ierr);
808   ierr = PetscTypeCompare((PetscObject)viewer,DRAW_VIEWER,&isdraw);CHKERRQ(ierr);
809   ierr = PetscTypeCompare((PetscObject)viewer,SOCKET_VIEWER,&issocket);CHKERRQ(ierr);
810   ierr = PetscTypeCompare((PetscObject)viewer,BINARY_VIEWER,&isbinary);CHKERRQ(ierr);
811   if (isascii || isdraw || issocket || isbinary) {
812     ierr = MatView_MPISBAIJ_ASCIIorDraworSocket(mat,viewer);CHKERRQ(ierr);
813   } else {
814     SETERRQ1(1,"Viewer type %s not supported by MPISBAIJ matrices",((PetscObject)viewer)->type_name);
815   }
816   PetscFunctionReturn(0);
817 }
818 
819 #undef __FUNC__
820 #define __FUNC__ /*<a name=""></a>*/"MatDestroy_MPISBAIJ"
821 int MatDestroy_MPISBAIJ(Mat mat)
822 {
823   Mat_MPISBAIJ *baij = (Mat_MPISBAIJ*)mat->data;
824   int         ierr;
825 
826   PetscFunctionBegin;
827 
828   if (mat->mapping) {
829     ierr = ISLocalToGlobalMappingDestroy(mat->mapping);CHKERRQ(ierr);
830   }
831   if (mat->bmapping) {
832     ierr = ISLocalToGlobalMappingDestroy(mat->bmapping);CHKERRQ(ierr);
833   }
834   if (mat->rmap) {
835     ierr = MapDestroy(mat->rmap);CHKERRQ(ierr);
836   }
837   if (mat->cmap) {
838     ierr = MapDestroy(mat->cmap);CHKERRQ(ierr);
839   }
840 #if defined(PETSC_USE_LOG)
841   PLogObjectState((PetscObject)mat,"Rows=%d,Cols=%d",baij->M,baij->N);
842 #endif
843 
844   ierr = MatStashDestroy_Private(&mat->stash);CHKERRQ(ierr);
845   ierr = MatStashDestroy_Private(&mat->bstash);CHKERRQ(ierr);
846 
847   ierr = PetscFree(baij->rowners);CHKERRQ(ierr);
848   ierr = MatDestroy(baij->A);CHKERRQ(ierr);
849   ierr = MatDestroy(baij->B);CHKERRQ(ierr);
850 #if defined (PETSC_USE_CTABLE)
851   if (baij->colmap) {ierr = PetscTableDelete(baij->colmap);CHKERRQ(ierr);}
852 #else
853   if (baij->colmap) {ierr = PetscFree(baij->colmap);CHKERRQ(ierr);}
854 #endif
855   if (baij->garray) {ierr = PetscFree(baij->garray);CHKERRQ(ierr);}
856   if (baij->lvec)   {ierr = VecDestroy(baij->lvec);CHKERRQ(ierr);}
857   if (baij->Mvctx)  {ierr = VecScatterDestroy(baij->Mvctx);CHKERRQ(ierr);}
858   if (baij->rowvalues) {ierr = PetscFree(baij->rowvalues);CHKERRQ(ierr);}
859   if (baij->barray) {ierr = PetscFree(baij->barray);CHKERRQ(ierr);}
860   if (baij->hd) {ierr = PetscFree(baij->hd);CHKERRQ(ierr);}
861 #if defined(PETSC_USE_MAT_SINGLE)
862   if (baij->setvaluescopy) {ierr = PetscFree(baij->setvaluescopy);CHKERRQ(ierr);}
863 #endif
864   ierr = PetscFree(baij);CHKERRQ(ierr);
865   PLogObjectDestroy(mat);
866   PetscHeaderDestroy(mat);
867   PetscFunctionReturn(0);
868 }
869 
870 #undef __FUNC__
871 #define __FUNC__ /*<a name=""></a>*/"MatMult_MPISBAIJ"
872 int MatMult_MPISBAIJ(Mat A,Vec xx,Vec yy)
873 {
874   Mat_MPISBAIJ *a = (Mat_MPISBAIJ*)A->data;
875   int         ierr,nt;
876 
877   PetscFunctionBegin;
878   ierr = VecGetLocalSize(xx,&nt);CHKERRQ(ierr);
879   if (nt != a->n) {
880     SETERRQ(PETSC_ERR_ARG_SIZ,"Incompatible partition of A and xx");
881   }
882   ierr = VecGetLocalSize(yy,&nt);CHKERRQ(ierr);
883   if (nt != a->m) {
884     SETERRQ(PETSC_ERR_ARG_SIZ,"Incompatible parition of A and yy");
885   }
886 
887   ierr = VecScatterBegin(xx,a->lvec,INSERT_VALUES,SCATTER_FORWARD,a->Mvctx);CHKERRQ(ierr);
888   /* do diagonal part */
889   ierr = (*a->A->ops->mult)(a->A,xx,yy);CHKERRQ(ierr);
890   /* do supperdiagonal part */
891   ierr = VecScatterEnd(xx,a->lvec,INSERT_VALUES,SCATTER_FORWARD,a->Mvctx);CHKERRQ(ierr);
892   ierr = (*a->B->ops->multadd)(a->B,a->lvec,yy,yy);CHKERRQ(ierr);
893   /* do subdiagonal part */
894   ierr = (*a->B->ops->multtranspose)(a->B,xx,a->lvec);CHKERRQ(ierr);
895   ierr = VecScatterBegin(a->lvec,yy,ADD_VALUES,SCATTER_REVERSE,a->Mvctx);CHKERRQ(ierr);
896   ierr = VecScatterEnd(a->lvec,yy,ADD_VALUES,SCATTER_REVERSE,a->Mvctx);CHKERRQ(ierr);
897 
898   PetscFunctionReturn(0);
899 }
900 
901 #undef __FUNC__
902 #define __FUNC__ /*<a name=""></a>*/"MatMultAdd_MPISBAIJ"
903 int MatMultAdd_MPISBAIJ(Mat A,Vec xx,Vec yy,Vec zz)
904 {
905   Mat_MPISBAIJ *a = (Mat_MPISBAIJ*)A->data;
906   int        ierr;
907 
908   PetscFunctionBegin;
909   ierr = VecScatterBegin(xx,a->lvec,INSERT_VALUES,SCATTER_FORWARD,a->Mvctx);CHKERRQ(ierr);
910   /* do diagonal part */
911   ierr = (*a->A->ops->multadd)(a->A,xx,yy,zz);CHKERRQ(ierr);
912   /* do supperdiagonal part */
913   ierr = VecScatterEnd(xx,a->lvec,INSERT_VALUES,SCATTER_FORWARD,a->Mvctx);CHKERRQ(ierr);
914   ierr = (*a->B->ops->multadd)(a->B,a->lvec,zz,zz);CHKERRQ(ierr);
915 
916   /* do subdiagonal part */
917   ierr = (*a->B->ops->multtranspose)(a->B,xx,a->lvec);CHKERRQ(ierr);
918   ierr = VecScatterBegin(a->lvec,zz,ADD_VALUES,SCATTER_REVERSE,a->Mvctx);CHKERRQ(ierr);
919   ierr = VecScatterEnd(a->lvec,zz,ADD_VALUES,SCATTER_REVERSE,a->Mvctx);CHKERRQ(ierr);
920 
921   PetscFunctionReturn(0);
922 }
923 
924 #undef __FUNC__
925 #define __FUNC__ /*<a name=""></a>*/"MatMultTranspose_MPISBAIJ"
926 int MatMultTranspose_MPISBAIJ(Mat A,Vec xx,Vec yy)
927 {
928   PetscFunctionBegin;
929   SETERRQ(1,"Matrix is symmetric. Call MatMult().");
930   /* PetscFunctionReturn(0); */
931 }
932 
933 #undef __FUNC__
934 #define __FUNC__ /*<a name=""></a>*/"MatMultTransposeAdd_MPISBAIJ"
935 int MatMultTransposeAdd_MPISBAIJ(Mat A,Vec xx,Vec yy,Vec zz)
936 {
937   PetscFunctionBegin;
938   SETERRQ(1,"Matrix is symmetric. Call MatMultAdd().");
939   /* PetscFunctionReturn(0); */
940 }
941 
942 /*
943   This only works correctly for square matrices where the subblock A->A is the
944    diagonal block
945 */
946 #undef __FUNC__
947 #define __FUNC__ /*<a name=""></a>*/"MatGetDiagonal_MPISBAIJ"
948 int MatGetDiagonal_MPISBAIJ(Mat A,Vec v)
949 {
950   Mat_MPISBAIJ *a = (Mat_MPISBAIJ*)A->data;
951   int         ierr;
952 
953   PetscFunctionBegin;
954   /* if (a->M != a->N) SETERRQ(PETSC_ERR_SUP,"Supports only square matrix where A->A is diag block"); */
955   ierr = MatGetDiagonal(a->A,v);CHKERRQ(ierr);
956   PetscFunctionReturn(0);
957 }
958 
959 #undef __FUNC__
960 #define __FUNC__ /*<a name=""></a>*/"MatScale_MPISBAIJ"
961 int MatScale_MPISBAIJ(Scalar *aa,Mat A)
962 {
963   Mat_MPISBAIJ *a = (Mat_MPISBAIJ*)A->data;
964   int         ierr;
965 
966   PetscFunctionBegin;
967   ierr = MatScale(aa,a->A);CHKERRQ(ierr);
968   ierr = MatScale(aa,a->B);CHKERRQ(ierr);
969   PetscFunctionReturn(0);
970 }
971 
972 #undef __FUNC__
973 #define __FUNC__ /*<a name=""></a>*/"MatGetSize_MPISBAIJ"
974 int MatGetSize_MPISBAIJ(Mat matin,int *m,int *n)
975 {
976   Mat_MPISBAIJ *mat = (Mat_MPISBAIJ*)matin->data;
977 
978   PetscFunctionBegin;
979   if (m) *m = mat->M;
980   if (n) *n = mat->N;
981   PetscFunctionReturn(0);
982 }
983 
984 #undef __FUNC__
985 #define __FUNC__ /*<a name=""></a>*/"MatGetLocalSize_MPISBAIJ"
986 int MatGetLocalSize_MPISBAIJ(Mat matin,int *m,int *n)
987 {
988   Mat_MPISBAIJ *mat = (Mat_MPISBAIJ*)matin->data;
989 
990   PetscFunctionBegin;
991   *m = mat->m; *n = mat->n;
992   PetscFunctionReturn(0);
993 }
994 
995 #undef __FUNC__
996 #define __FUNC__ /*<a name=""></a>*/"MatGetOwnershipRange_MPISBAIJ"
997 int MatGetOwnershipRange_MPISBAIJ(Mat matin,int *m,int *n)
998 {
999   Mat_MPISBAIJ *mat = (Mat_MPISBAIJ*)matin->data;
1000 
1001   PetscFunctionBegin;
1002   if (m) *m = mat->rstart*mat->bs;
1003   if (n) *n = mat->rend*mat->bs;
1004   PetscFunctionReturn(0);
1005 }
1006 
1007 #undef __FUNC__
1008 #define __FUNC__ /*<a name=""></a>*/"MatGetRow_MPISBAIJ"
1009 int MatGetRow_MPISBAIJ(Mat matin,int row,int *nz,int **idx,Scalar **v)
1010 {
1011   Mat_MPISBAIJ *mat = (Mat_MPISBAIJ*)matin->data;
1012   Scalar     *vworkA,*vworkB,**pvA,**pvB,*v_p;
1013   int        bs = mat->bs,bs2 = mat->bs2,i,ierr,*cworkA,*cworkB,**pcA,**pcB;
1014   int        nztot,nzA,nzB,lrow,brstart = mat->rstart*bs,brend = mat->rend*bs;
1015   int        *cmap,*idx_p,cstart = mat->cstart;
1016 
1017   PetscFunctionBegin;
1018   if (mat->getrowactive == PETSC_TRUE) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Already active");
1019   mat->getrowactive = PETSC_TRUE;
1020 
1021   if (!mat->rowvalues && (idx || v)) {
1022     /*
1023         allocate enough space to hold information from the longest row.
1024     */
1025     Mat_SeqSBAIJ *Aa = (Mat_SeqSBAIJ*)mat->A->data;
1026     Mat_SeqBAIJ  *Ba = (Mat_SeqBAIJ*)mat->B->data;
1027     int     max = 1,mbs = mat->mbs,tmp;
1028     for (i=0; i<mbs; i++) {
1029       tmp = Aa->i[i+1] - Aa->i[i] + Ba->i[i+1] - Ba->i[i]; /* row length */
1030       if (max < tmp) { max = tmp; }
1031     }
1032     mat->rowvalues = (Scalar*)PetscMalloc(max*bs2*(sizeof(int)+sizeof(Scalar)));CHKPTRQ(mat->rowvalues);
1033     mat->rowindices = (int*)(mat->rowvalues + max*bs2);
1034   }
1035 
1036   if (row < brstart || row >= brend) SETERRQ(PETSC_ERR_SUP,"Only local rows")
1037   lrow = row - brstart;  /* local row index */
1038 
1039   pvA = &vworkA; pcA = &cworkA; pvB = &vworkB; pcB = &cworkB;
1040   if (!v)   {pvA = 0; pvB = 0;}
1041   if (!idx) {pcA = 0; if (!v) pcB = 0;}
1042   ierr = (*mat->A->ops->getrow)(mat->A,lrow,&nzA,pcA,pvA);CHKERRQ(ierr);
1043   ierr = (*mat->B->ops->getrow)(mat->B,lrow,&nzB,pcB,pvB);CHKERRQ(ierr);
1044   nztot = nzA + nzB;
1045 
1046   cmap  = mat->garray;
1047   if (v  || idx) {
1048     if (nztot) {
1049       /* Sort by increasing column numbers, assuming A and B already sorted */
1050       int imark = -1;
1051       if (v) {
1052         *v = v_p = mat->rowvalues;
1053         for (i=0; i<nzB; i++) {
1054           if (cmap[cworkB[i]/bs] < cstart)   v_p[i] = vworkB[i];
1055           else break;
1056         }
1057         imark = i;
1058         for (i=0; i<nzA; i++)     v_p[imark+i] = vworkA[i];
1059         for (i=imark; i<nzB; i++) v_p[nzA+i]   = vworkB[i];
1060       }
1061       if (idx) {
1062         *idx = idx_p = mat->rowindices;
1063         if (imark > -1) {
1064           for (i=0; i<imark; i++) {
1065             idx_p[i] = cmap[cworkB[i]/bs]*bs + cworkB[i]%bs;
1066           }
1067         } else {
1068           for (i=0; i<nzB; i++) {
1069             if (cmap[cworkB[i]/bs] < cstart)
1070               idx_p[i] = cmap[cworkB[i]/bs]*bs + cworkB[i]%bs ;
1071             else break;
1072           }
1073           imark = i;
1074         }
1075         for (i=0; i<nzA; i++)     idx_p[imark+i] = cstart*bs + cworkA[i];
1076         for (i=imark; i<nzB; i++) idx_p[nzA+i]   = cmap[cworkB[i]/bs]*bs + cworkB[i]%bs ;
1077       }
1078     } else {
1079       if (idx) *idx = 0;
1080       if (v)   *v   = 0;
1081     }
1082   }
1083   *nz = nztot;
1084   ierr = (*mat->A->ops->restorerow)(mat->A,lrow,&nzA,pcA,pvA);CHKERRQ(ierr);
1085   ierr = (*mat->B->ops->restorerow)(mat->B,lrow,&nzB,pcB,pvB);CHKERRQ(ierr);
1086   PetscFunctionReturn(0);
1087 }
1088 
1089 #undef __FUNC__
1090 #define __FUNC__ /*<a name=""></a>*/"MatRestoreRow_MPISBAIJ"
1091 int MatRestoreRow_MPISBAIJ(Mat mat,int row,int *nz,int **idx,Scalar **v)
1092 {
1093   Mat_MPISBAIJ *baij = (Mat_MPISBAIJ*)mat->data;
1094 
1095   PetscFunctionBegin;
1096   if (baij->getrowactive == PETSC_FALSE) {
1097     SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"MatGetRow not called");
1098   }
1099   baij->getrowactive = PETSC_FALSE;
1100   PetscFunctionReturn(0);
1101 }
1102 
1103 #undef __FUNC__
1104 #define __FUNC__ /*<a name=""></a>*/"MatGetBlockSize_MPISBAIJ"
1105 int MatGetBlockSize_MPISBAIJ(Mat mat,int *bs)
1106 {
1107   Mat_MPISBAIJ *baij = (Mat_MPISBAIJ*)mat->data;
1108 
1109   PetscFunctionBegin;
1110   *bs = baij->bs;
1111   PetscFunctionReturn(0);
1112 }
1113 
1114 #undef __FUNC__
1115 #define __FUNC__ /*<a name=""></a>*/"MatZeroEntries_MPISBAIJ"
1116 int MatZeroEntries_MPISBAIJ(Mat A)
1117 {
1118   Mat_MPISBAIJ *l = (Mat_MPISBAIJ*)A->data;
1119   int         ierr;
1120 
1121   PetscFunctionBegin;
1122   ierr = MatZeroEntries(l->A);CHKERRQ(ierr);
1123   ierr = MatZeroEntries(l->B);CHKERRQ(ierr);
1124   PetscFunctionReturn(0);
1125 }
1126 
1127 #undef __FUNC__
1128 #define __FUNC__ /*<a name=""></a>*/"MatGetInfo_MPISBAIJ"
1129 int MatGetInfo_MPISBAIJ(Mat matin,MatInfoType flag,MatInfo *info)
1130 {
1131   Mat_MPISBAIJ *a = (Mat_MPISBAIJ*)matin->data;
1132   Mat         A = a->A,B = a->B;
1133   int         ierr;
1134   PetscReal   isend[5],irecv[5];
1135 
1136   PetscFunctionBegin;
1137   info->block_size     = (double)a->bs;
1138   ierr = MatGetInfo(A,MAT_LOCAL,info);CHKERRQ(ierr);
1139   isend[0] = info->nz_used; isend[1] = info->nz_allocated; isend[2] = info->nz_unneeded;
1140   isend[3] = info->memory;  isend[4] = info->mallocs;
1141   ierr = MatGetInfo(B,MAT_LOCAL,info);CHKERRQ(ierr);
1142   isend[0] += info->nz_used; isend[1] += info->nz_allocated; isend[2] += info->nz_unneeded;
1143   isend[3] += info->memory;  isend[4] += info->mallocs;
1144   if (flag == MAT_LOCAL) {
1145     info->nz_used      = isend[0];
1146     info->nz_allocated = isend[1];
1147     info->nz_unneeded  = isend[2];
1148     info->memory       = isend[3];
1149     info->mallocs      = isend[4];
1150   } else if (flag == MAT_GLOBAL_MAX) {
1151     ierr = MPI_Allreduce(isend,irecv,5,MPI_DOUBLE,MPI_MAX,matin->comm);CHKERRQ(ierr);
1152     info->nz_used      = irecv[0];
1153     info->nz_allocated = irecv[1];
1154     info->nz_unneeded  = irecv[2];
1155     info->memory       = irecv[3];
1156     info->mallocs      = irecv[4];
1157   } else if (flag == MAT_GLOBAL_SUM) {
1158     ierr = MPI_Allreduce(isend,irecv,5,MPI_DOUBLE,MPI_SUM,matin->comm);CHKERRQ(ierr);
1159     info->nz_used      = irecv[0];
1160     info->nz_allocated = irecv[1];
1161     info->nz_unneeded  = irecv[2];
1162     info->memory       = irecv[3];
1163     info->mallocs      = irecv[4];
1164   } else {
1165     SETERRQ1(1,"Unknown MatInfoType argument %d",flag);
1166   }
1167   info->rows_global       = (double)a->M;
1168   info->columns_global    = (double)a->N;
1169   info->rows_local        = (double)a->m;
1170   info->columns_local     = (double)a->N;
1171   info->fill_ratio_given  = 0; /* no parallel LU/ILU/Cholesky */
1172   info->fill_ratio_needed = 0;
1173   info->factor_mallocs    = 0;
1174   PetscFunctionReturn(0);
1175 }
1176 
1177 #undef __FUNC__
1178 #define __FUNC__ /*<a name=""></a>*/"MatSetOption_MPISBAIJ"
1179 int MatSetOption_MPISBAIJ(Mat A,MatOption op)
1180 {
1181   Mat_MPISBAIJ *a = (Mat_MPISBAIJ*)A->data;
1182   int         ierr;
1183 
1184   PetscFunctionBegin;
1185   if (op == MAT_NO_NEW_NONZERO_LOCATIONS ||
1186       op == MAT_YES_NEW_NONZERO_LOCATIONS ||
1187       op == MAT_COLUMNS_UNSORTED ||
1188       op == MAT_COLUMNS_SORTED ||
1189       op == MAT_NEW_NONZERO_ALLOCATION_ERR ||
1190       op == MAT_KEEP_ZEROED_ROWS ||
1191       op == MAT_NEW_NONZERO_LOCATION_ERR) {
1192         ierr = MatSetOption(a->A,op);CHKERRQ(ierr);
1193         ierr = MatSetOption(a->B,op);CHKERRQ(ierr);
1194   } else if (op == MAT_ROW_ORIENTED) {
1195         a->roworiented = PETSC_TRUE;
1196         ierr = MatSetOption(a->A,op);CHKERRQ(ierr);
1197         ierr = MatSetOption(a->B,op);CHKERRQ(ierr);
1198   } else if (op == MAT_ROWS_SORTED ||
1199              op == MAT_ROWS_UNSORTED ||
1200              op == MAT_SYMMETRIC ||
1201              op == MAT_STRUCTURALLY_SYMMETRIC ||
1202              op == MAT_YES_NEW_DIAGONALS ||
1203              op == MAT_USE_HASH_TABLE) {
1204     PLogInfo(A,"Info:MatSetOption_MPIBAIJ:Option ignored\n");
1205   } else if (op == MAT_COLUMN_ORIENTED) {
1206     a->roworiented = PETSC_FALSE;
1207     ierr = MatSetOption(a->A,op);CHKERRQ(ierr);
1208     ierr = MatSetOption(a->B,op);CHKERRQ(ierr);
1209   } else if (op == MAT_IGNORE_OFF_PROC_ENTRIES) {
1210     a->donotstash = PETSC_TRUE;
1211   } else if (op == MAT_NO_NEW_DIAGONALS) {
1212     SETERRQ(PETSC_ERR_SUP,"MAT_NO_NEW_DIAGONALS");
1213   } else if (op == MAT_USE_HASH_TABLE) {
1214     a->ht_flag = PETSC_TRUE;
1215   } else {
1216     SETERRQ(PETSC_ERR_SUP,"unknown option");
1217   }
1218   PetscFunctionReturn(0);
1219 }
1220 
1221 #undef __FUNC__
1222 #define __FUNC__ /*<a name=""></a>*/"MatTranspose_MPISBAIJ("
1223 int MatTranspose_MPISBAIJ(Mat A,Mat *matout)
1224 {
1225   PetscFunctionBegin;
1226   SETERRQ(1,"Matrix is symmetric. MatTranspose() should not be called");
1227   /* PetscFunctionReturn(0); */
1228 }
1229 
1230 #undef __FUNC__
1231 #define __FUNC__ /*<a name=""></a>*/"MatDiagonalScale_MPISBAIJ"
1232 int MatDiagonalScale_MPISBAIJ(Mat mat,Vec ll,Vec rr)
1233 {
1234   Mat_MPISBAIJ *baij = (Mat_MPISBAIJ*)mat->data;
1235   Mat         a = baij->A,b = baij->B;
1236   int         ierr,s1,s2,s3;
1237 
1238   PetscFunctionBegin;
1239   if (ll != rr) {
1240     SETERRQ(PETSC_ERR_ARG_OUTOFRANGE,"For symmetric format, left and right scaling vectors must be same\n");
1241   }
1242   ierr = MatGetLocalSize(mat,&s2,&s3);CHKERRQ(ierr);
1243   if (rr) {
1244     ierr = VecGetLocalSize(rr,&s1);CHKERRQ(ierr);
1245     if (s1!=s3) SETERRQ(PETSC_ERR_ARG_SIZ,"right vector non-conforming local size");
1246     /* Overlap communication with computation. */
1247     ierr = VecScatterBegin(rr,baij->lvec,INSERT_VALUES,SCATTER_FORWARD,baij->Mvctx);CHKERRQ(ierr);
1248     /*} if (ll) { */
1249     ierr = VecGetLocalSize(ll,&s1);CHKERRQ(ierr);
1250     if (s1!=s2) SETERRQ(PETSC_ERR_ARG_SIZ,"left vector non-conforming local size");
1251     ierr = (*b->ops->diagonalscale)(b,ll,PETSC_NULL);CHKERRQ(ierr);
1252     /* } */
1253   /* scale  the diagonal block */
1254   ierr = (*a->ops->diagonalscale)(a,ll,rr);CHKERRQ(ierr);
1255 
1256   /* if (rr) { */
1257     /* Do a scatter end and then right scale the off-diagonal block */
1258     ierr = VecScatterEnd(rr,baij->lvec,INSERT_VALUES,SCATTER_FORWARD,baij->Mvctx);CHKERRQ(ierr);
1259     ierr = (*b->ops->diagonalscale)(b,PETSC_NULL,baij->lvec);CHKERRQ(ierr);
1260   }
1261 
1262   PetscFunctionReturn(0);
1263 }
1264 
1265 #undef __FUNC__
1266 #define __FUNC__ /*<a name=""></a>*/"MatZeroRows_MPISBAIJ"
1267 int MatZeroRows_MPISBAIJ(Mat A,IS is,Scalar *diag)
1268 {
1269   Mat_MPISBAIJ   *l = (Mat_MPISBAIJ*)A->data;
1270   int            i,ierr,N,*rows,*owners = l->rowners,size = l->size;
1271   int            *procs,*nprocs,j,found,idx,nsends,*work,row;
1272   int            nmax,*svalues,*starts,*owner,nrecvs,rank = l->rank;
1273   int            *rvalues,tag = A->tag,count,base,slen,n,*source;
1274   int            *lens,imdex,*lrows,*values,bs=l->bs,rstart_bs=l->rstart_bs;
1275   MPI_Comm       comm = A->comm;
1276   MPI_Request    *send_waits,*recv_waits;
1277   MPI_Status     recv_status,*send_status;
1278   IS             istmp;
1279 
1280   PetscFunctionBegin;
1281   ierr = ISGetSize(is,&N);CHKERRQ(ierr);
1282   ierr = ISGetIndices(is,&rows);CHKERRQ(ierr);
1283 
1284   /*  first count number of contributors to each processor */
1285   nprocs = (int*)PetscMalloc(2*size*sizeof(int));CHKPTRQ(nprocs);
1286   ierr   = PetscMemzero(nprocs,2*size*sizeof(int));CHKERRQ(ierr);
1287   procs  = nprocs + size;
1288   owner  = (int*)PetscMalloc((N+1)*sizeof(int));CHKPTRQ(owner); /* see note*/
1289   for (i=0; i<N; i++) {
1290     idx   = rows[i];
1291     found = 0;
1292     for (j=0; j<size; j++) {
1293       if (idx >= owners[j]*bs && idx < owners[j+1]*bs) {
1294         nprocs[j]++; procs[j] = 1; owner[i] = j; found = 1; break;
1295       }
1296     }
1297     if (!found) SETERRQ(PETSC_ERR_ARG_OUTOFRANGE,"Index out of range");
1298   }
1299   nsends = 0;  for (i=0; i<size; i++) { nsends += procs[i];}
1300 
1301   /* inform other processors of number of messages and max length*/
1302   work   = (int*)PetscMalloc(2*size*sizeof(int));CHKPTRQ(work);
1303   ierr   = MPI_Allreduce(nprocs,work,2*size,MPI_INT,PetscMaxSum_Op,comm);CHKERRQ(ierr);
1304   nmax   = work[rank];
1305   nrecvs = work[size+rank];
1306   ierr = PetscFree(work);CHKERRQ(ierr);
1307 
1308   /* post receives:   */
1309   rvalues = (int*)PetscMalloc((nrecvs+1)*(nmax+1)*sizeof(int));CHKPTRQ(rvalues);
1310   recv_waits = (MPI_Request*)PetscMalloc((nrecvs+1)*sizeof(MPI_Request));CHKPTRQ(recv_waits);
1311   for (i=0; i<nrecvs; i++) {
1312     ierr = MPI_Irecv(rvalues+nmax*i,nmax,MPI_INT,MPI_ANY_SOURCE,tag,comm,recv_waits+i);CHKERRQ(ierr);
1313   }
1314 
1315   /* do sends:
1316      1) starts[i] gives the starting index in svalues for stuff going to
1317      the ith processor
1318   */
1319   svalues    = (int*)PetscMalloc((N+1)*sizeof(int));CHKPTRQ(svalues);
1320   send_waits = (MPI_Request*)PetscMalloc((nsends+1)*sizeof(MPI_Request));CHKPTRQ(send_waits);
1321   starts     = (int*)PetscMalloc((size+1)*sizeof(int));CHKPTRQ(starts);
1322   starts[0]  = 0;
1323   for (i=1; i<size; i++) { starts[i] = starts[i-1] + nprocs[i-1];}
1324   for (i=0; i<N; i++) {
1325     svalues[starts[owner[i]]++] = rows[i];
1326   }
1327   ierr = ISRestoreIndices(is,&rows);CHKERRQ(ierr);
1328 
1329   starts[0] = 0;
1330   for (i=1; i<size+1; i++) { starts[i] = starts[i-1] + nprocs[i-1];}
1331   count = 0;
1332   for (i=0; i<size; i++) {
1333     if (procs[i]) {
1334       ierr = MPI_Isend(svalues+starts[i],nprocs[i],MPI_INT,i,tag,comm,send_waits+count++);CHKERRQ(ierr);
1335     }
1336   }
1337   ierr = PetscFree(starts);CHKERRQ(ierr);
1338 
1339   base = owners[rank]*bs;
1340 
1341   /*  wait on receives */
1342   lens   = (int*)PetscMalloc(2*(nrecvs+1)*sizeof(int));CHKPTRQ(lens);
1343   source = lens + nrecvs;
1344   count  = nrecvs; slen = 0;
1345   while (count) {
1346     ierr = MPI_Waitany(nrecvs,recv_waits,&imdex,&recv_status);CHKERRQ(ierr);
1347     /* unpack receives into our local space */
1348     ierr = MPI_Get_count(&recv_status,MPI_INT,&n);CHKERRQ(ierr);
1349     source[imdex]  = recv_status.MPI_SOURCE;
1350     lens[imdex]    = n;
1351     slen          += n;
1352     count--;
1353   }
1354   ierr = PetscFree(recv_waits);CHKERRQ(ierr);
1355 
1356   /* move the data into the send scatter */
1357   lrows = (int*)PetscMalloc((slen+1)*sizeof(int));CHKPTRQ(lrows);
1358   count = 0;
1359   for (i=0; i<nrecvs; i++) {
1360     values = rvalues + i*nmax;
1361     for (j=0; j<lens[i]; j++) {
1362       lrows[count++] = values[j] - base;
1363     }
1364   }
1365   ierr = PetscFree(rvalues);CHKERRQ(ierr);
1366   ierr = PetscFree(lens);CHKERRQ(ierr);
1367   ierr = PetscFree(owner);CHKERRQ(ierr);
1368   ierr = PetscFree(nprocs);CHKERRQ(ierr);
1369 
1370   /* actually zap the local rows */
1371   ierr = ISCreateGeneral(PETSC_COMM_SELF,slen,lrows,&istmp);CHKERRQ(ierr);
1372   PLogObjectParent(A,istmp);
1373 
1374   /*
1375         Zero the required rows. If the "diagonal block" of the matrix
1376      is square and the user wishes to set the diagonal we use seperate
1377      code so that MatSetValues() is not called for each diagonal allocating
1378      new memory, thus calling lots of mallocs and slowing things down.
1379 
1380        Contributed by: Mathew Knepley
1381   */
1382   /* must zero l->B before l->A because the (diag) case below may put values into l->B*/
1383   ierr = MatZeroRows_SeqBAIJ(l->B,istmp,0);CHKERRQ(ierr);
1384   if (diag && (l->A->M == l->A->N)) {
1385     ierr = MatZeroRows_SeqSBAIJ(l->A,istmp,diag);CHKERRQ(ierr);
1386   } else if (diag) {
1387     ierr = MatZeroRows_SeqSBAIJ(l->A,istmp,0);CHKERRQ(ierr);
1388     if (((Mat_SeqSBAIJ*)l->A->data)->nonew) {
1389       SETERRQ(PETSC_ERR_SUP,"MatZeroRows() on rectangular matrices cannot be used with the Mat options \n\
1390 MAT_NO_NEW_NONZERO_LOCATIONS,MAT_NEW_NONZERO_LOCATION_ERR,MAT_NEW_NONZERO_ALLOCATION_ERR");
1391     }
1392     for (i=0; i<slen; i++) {
1393       row  = lrows[i] + rstart_bs;
1394       ierr = MatSetValues(A,1,&row,1,&row,diag,INSERT_VALUES);CHKERRQ(ierr);
1395     }
1396     ierr = MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
1397     ierr = MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
1398   } else {
1399     ierr = MatZeroRows_SeqSBAIJ(l->A,istmp,0);CHKERRQ(ierr);
1400   }
1401 
1402   ierr = ISDestroy(istmp);CHKERRQ(ierr);
1403   ierr = PetscFree(lrows);CHKERRQ(ierr);
1404 
1405   /* wait on sends */
1406   if (nsends) {
1407     send_status = (MPI_Status*)PetscMalloc(nsends*sizeof(MPI_Status));CHKPTRQ(send_status);
1408     ierr        = MPI_Waitall(nsends,send_waits,send_status);CHKERRQ(ierr);
1409     ierr        = PetscFree(send_status);CHKERRQ(ierr);
1410   }
1411   ierr = PetscFree(send_waits);CHKERRQ(ierr);
1412   ierr = PetscFree(svalues);CHKERRQ(ierr);
1413 
1414   PetscFunctionReturn(0);
1415 }
1416 
1417 #undef __FUNC__
1418 #define __FUNC__ /*<a name=""></a>*/"MatPrintHelp_MPISBAIJ"
1419 int MatPrintHelp_MPISBAIJ(Mat A)
1420 {
1421   Mat_MPISBAIJ *a   = (Mat_MPISBAIJ*)A->data;
1422   MPI_Comm    comm = A->comm;
1423   static int  called = 0;
1424   int         ierr;
1425 
1426   PetscFunctionBegin;
1427   if (!a->rank) {
1428     ierr = MatPrintHelp_SeqSBAIJ(a->A);CHKERRQ(ierr);
1429   }
1430   if (called) {PetscFunctionReturn(0);} else called = 1;
1431   ierr = (*PetscHelpPrintf)(comm," Options for MATMPISBAIJ matrix format (the defaults):\n");CHKERRQ(ierr);
1432   ierr = (*PetscHelpPrintf)(comm,"  -mat_use_hash_table <factor>: Use hashtable for efficient matrix assembly\n");CHKERRQ(ierr);
1433   PetscFunctionReturn(0);
1434 }
1435 
1436 #undef __FUNC__
1437 #define __FUNC__ /*<a name=""></a>*/"MatSetUnfactored_MPISBAIJ"
1438 int MatSetUnfactored_MPISBAIJ(Mat A)
1439 {
1440   Mat_MPISBAIJ *a   = (Mat_MPISBAIJ*)A->data;
1441   int         ierr;
1442 
1443   PetscFunctionBegin;
1444   ierr = MatSetUnfactored(a->A);CHKERRQ(ierr);
1445   PetscFunctionReturn(0);
1446 }
1447 
1448 static int MatDuplicate_MPISBAIJ(Mat,MatDuplicateOption,Mat *);
1449 
1450 #undef __FUNC__
1451 #define __FUNC__ /*<a name=""></a>*/"MatEqual_MPISBAIJ"
1452 int MatEqual_MPISBAIJ(Mat A,Mat B,PetscTruth *flag)
1453 {
1454   Mat_MPISBAIJ *matB = (Mat_MPISBAIJ*)B->data,*matA = (Mat_MPISBAIJ*)A->data;
1455   Mat         a,b,c,d;
1456   PetscTruth  flg;
1457   int         ierr;
1458 
1459   PetscFunctionBegin;
1460   if (B->type != MATMPISBAIJ) SETERRQ(PETSC_ERR_ARG_INCOMP,"Matrices must be same type");
1461   a = matA->A; b = matA->B;
1462   c = matB->A; d = matB->B;
1463 
1464   ierr = MatEqual(a,c,&flg);CHKERRQ(ierr);
1465   if (flg == PETSC_TRUE) {
1466     ierr = MatEqual(b,d,&flg);CHKERRQ(ierr);
1467   }
1468   ierr = MPI_Allreduce(&flg,flag,1,MPI_INT,MPI_LAND,A->comm);CHKERRQ(ierr);
1469   PetscFunctionReturn(0);
1470 }
1471 
1472 /* -------------------------------------------------------------------*/
1473 static struct _MatOps MatOps_Values = {
1474   MatSetValues_MPISBAIJ,
1475   MatGetRow_MPISBAIJ,
1476   MatRestoreRow_MPISBAIJ,
1477   MatMult_MPISBAIJ,
1478   MatMultAdd_MPISBAIJ,
1479   MatMultTranspose_MPISBAIJ,
1480   MatMultTransposeAdd_MPISBAIJ,
1481   0,
1482   0,
1483   0,
1484   0,
1485   0,
1486   0,
1487   0,
1488   MatTranspose_MPISBAIJ,
1489   MatGetInfo_MPISBAIJ,
1490   MatEqual_MPISBAIJ,
1491   MatGetDiagonal_MPISBAIJ,
1492   MatDiagonalScale_MPISBAIJ,
1493   MatNorm_MPISBAIJ,
1494   MatAssemblyBegin_MPISBAIJ,
1495   MatAssemblyEnd_MPISBAIJ,
1496   0,
1497   MatSetOption_MPISBAIJ,
1498   MatZeroEntries_MPISBAIJ,
1499   MatZeroRows_MPISBAIJ,
1500   0,
1501   0,
1502   0,
1503   0,
1504   MatGetSize_MPISBAIJ,
1505   MatGetLocalSize_MPISBAIJ,
1506   MatGetOwnershipRange_MPISBAIJ,
1507   0,
1508   0,
1509   0,
1510   0,
1511   MatDuplicate_MPISBAIJ,
1512   0,
1513   0,
1514   0,
1515   0,
1516   0,
1517   MatGetSubMatrices_MPISBAIJ,
1518   MatIncreaseOverlap_MPISBAIJ,
1519   MatGetValues_MPISBAIJ,
1520   0,
1521   MatPrintHelp_MPISBAIJ,
1522   MatScale_MPISBAIJ,
1523   0,
1524   0,
1525   0,
1526   MatGetBlockSize_MPISBAIJ,
1527   0,
1528   0,
1529   0,
1530   0,
1531   0,
1532   0,
1533   MatSetUnfactored_MPISBAIJ,
1534   0,
1535   MatSetValuesBlocked_MPISBAIJ,
1536   0,
1537   0,
1538   0,
1539   MatGetMaps_Petsc,
1540   0,
1541   0,
1542   0,
1543   0,
1544   0,
1545   0,
1546   MatGetRowMax_MPISBAIJ};
1547 
1548 
1549 EXTERN_C_BEGIN
1550 #undef __FUNC__
1551 #define __FUNC__ /*<a name=""></a>*/"MatGetDiagonalBlock_MPISBAIJ"
1552 int MatGetDiagonalBlock_MPISBAIJ(Mat A,PetscTruth *iscopy,MatReuse reuse,Mat *a)
1553 {
1554   PetscFunctionBegin;
1555   *a      = ((Mat_MPISBAIJ *)A->data)->A;
1556   *iscopy = PETSC_FALSE;
1557   PetscFunctionReturn(0);
1558 }
1559 EXTERN_C_END
1560 
1561 #undef __FUNC__
1562 #define __FUNC__ /*<a name=""></a>*/"MatCreateMPISBAIJ"
1563 /*@C
1564    MatCreateMPISBAIJ - Creates a sparse parallel matrix in symmetric block AIJ format
1565    (block compressed row).  For good matrix assembly performance
1566    the user should preallocate the matrix storage by setting the parameters
1567    d_nz (or d_nnz) and o_nz (or o_nnz).  By setting these parameters accurately,
1568    performance can be increased by more than a factor of 50.
1569 
1570    Collective on MPI_Comm
1571 
1572    Input Parameters:
1573 +  comm - MPI communicator
1574 .  bs   - size of blockk
1575 .  m - number of local rows (or PETSC_DECIDE to have calculated if M is given)
1576            This value should be the same as the local size used in creating the
1577            y vector for the matrix-vector product y = Ax.
1578 .  n - number of local columns (or PETSC_DECIDE to have calculated if N is given)
1579            This value should be the same as the local size used in creating the
1580            x vector for the matrix-vector product y = Ax.
1581 .  M - number of global rows (or PETSC_DETERMINE to have calculated if m is given)
1582 .  N - number of global columns (or PETSC_DETERMINE to have calculated if n is given)
1583 .  d_nz  - number of block nonzeros per block row in diagonal portion of local
1584            submatrix  (same for all local rows)
1585 .  d_nnz - array containing the number of block nonzeros in the various block rows
1586            of the in diagonal portion of the local (possibly different for each block
1587            row) or PETSC_NULL.  You must leave room for the diagonal entry even if it is zero.
1588 .  o_nz  - number of block nonzeros per block row in the off-diagonal portion of local
1589            submatrix (same for all local rows).
1590 -  o_nnz - array containing the number of nonzeros in the various block rows of the
1591            off-diagonal portion of the local submatrix (possibly different for
1592            each block row) or PETSC_NULL.
1593 
1594    Output Parameter:
1595 .  A - the matrix
1596 
1597    Options Database Keys:
1598 .   -mat_no_unroll - uses code that does not unroll the loops in the
1599                      block calculations (much slower)
1600 .   -mat_block_size - size of the blocks to use
1601 .   -mat_mpi - use the parallel matrix data structures even on one processor
1602                (defaults to using SeqBAIJ format on one processor)
1603 
1604    Notes:
1605    The user MUST specify either the local or global matrix dimensions
1606    (possibly both).
1607 
1608    If PETSC_DECIDE or  PETSC_DETERMINE is used for a particular argument on one processor
1609    than it must be used on all processors that share the object for that argument.
1610 
1611    Storage Information:
1612    For a square global matrix we define each processor's diagonal portion
1613    to be its local rows and the corresponding columns (a square submatrix);
1614    each processor's off-diagonal portion encompasses the remainder of the
1615    local matrix (a rectangular submatrix).
1616 
1617    The user can specify preallocated storage for the diagonal part of
1618    the local submatrix with either d_nz or d_nnz (not both).  Set
1619    d_nz=PETSC_DEFAULT and d_nnz=PETSC_NULL for PETSc to control dynamic
1620    memory allocation.  Likewise, specify preallocated storage for the
1621    off-diagonal part of the local submatrix with o_nz or o_nnz (not both).
1622 
1623    Consider a processor that owns rows 3, 4 and 5 of a parallel matrix. In
1624    the figure below we depict these three local rows and all columns (0-11).
1625 
1626 .vb
1627            0 1 2 3 4 5 6 7 8 9 10 11
1628           -------------------
1629    row 3  |  o o o d d d o o o o o o
1630    row 4  |  o o o d d d o o o o o o
1631    row 5  |  o o o d d d o o o o o o
1632           -------------------
1633 .ve
1634 
1635    Thus, any entries in the d locations are stored in the d (diagonal)
1636    submatrix, and any entries in the o locations are stored in the
1637    o (off-diagonal) submatrix.  Note that the d and the o submatrices are
1638    stored simply in the MATSEQBAIJ format for compressed row storage.
1639 
1640    Now d_nz should indicate the number of block nonzeros per row in the d matrix,
1641    and o_nz should indicate the number of block nonzeros per row in the o matrix.
1642    In general, for PDE problems in which most nonzeros are near the diagonal,
1643    one expects d_nz >> o_nz.   For large problems you MUST preallocate memory
1644    or you will get TERRIBLE performance; see the users' manual chapter on
1645    matrices.
1646 
1647    Level: intermediate
1648 
1649 .keywords: matrix, block, aij, compressed row, sparse, parallel
1650 
1651 .seealso: MatCreate(), MatCreateSeqSBAIJ(), MatSetValues(), MatCreateMPIBAIJ()
1652 @*/
1653 
1654 int MatCreateMPISBAIJ(MPI_Comm comm,int bs,int m,int n,int M,int N,int d_nz,int *d_nnz,int o_nz,int *o_nnz,Mat *A)
1655 {
1656   Mat          B;
1657   Mat_MPISBAIJ  *b;
1658   int          ierr,i,sum[1],work[1],mbs,Mbs=PETSC_DECIDE,size;
1659   PetscTruth   flag1,flag2,flg;
1660 
1661   PetscFunctionBegin;
1662   if (M != N || m != n){ /* N and n are not used after this */
1663     SETERRQ(PETSC_ERR_ARG_OUTOFRANGE,"For symmetric format, set M=N and m=n");
1664   }
1665   ierr = OptionsGetInt(PETSC_NULL,"-mat_block_size",&bs,PETSC_NULL);CHKERRQ(ierr);
1666 
1667   if (bs < 1) SETERRQ(PETSC_ERR_ARG_OUTOFRANGE,"Invalid block size specified, must be positive");
1668   if (d_nz < -2) SETERRQ1(PETSC_ERR_ARG_OUTOFRANGE,"d_nz cannot be less than -2: value %d",d_nz);
1669   if (o_nz < -2) SETERRQ1(PETSC_ERR_ARG_OUTOFRANGE,"o_nz cannot be less than -2: value %d",o_nz);
1670   if (d_nnz) {
1671     for (i=0; i<m/bs; i++) {
1672       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]);
1673     }
1674   }
1675   if (o_nnz) {
1676     for (i=0; i<m/bs; i++) {
1677       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]);
1678     }
1679   }
1680 
1681   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
1682   ierr = OptionsHasName(PETSC_NULL,"-mat_mpisbaij",&flag1);CHKERRQ(ierr);
1683   ierr = OptionsHasName(PETSC_NULL,"-mat_mpi",&flag2);CHKERRQ(ierr);
1684   if (!flag1 && !flag2 && size == 1) {
1685     if (M == PETSC_DECIDE) M = m;
1686     ierr = MatCreateSeqSBAIJ(comm,bs,M,M,d_nz,d_nnz,A);CHKERRQ(ierr);
1687     PetscFunctionReturn(0);
1688   }
1689 
1690   *A = 0;
1691   PetscHeaderCreate(B,_p_Mat,struct _MatOps,MAT_COOKIE,MATMPISBAIJ,"Mat",comm,MatDestroy,MatView);
1692   PLogObjectCreate(B);
1693   B->data = (void*)(b = PetscNew(Mat_MPISBAIJ));CHKPTRQ(b);
1694   ierr    = PetscMemzero(b,sizeof(Mat_MPISBAIJ));CHKERRQ(ierr);
1695   ierr    = PetscMemcpy(B->ops,&MatOps_Values,sizeof(struct _MatOps));CHKERRQ(ierr);
1696 
1697   B->ops->destroy    = MatDestroy_MPISBAIJ;
1698   B->ops->view       = MatView_MPISBAIJ;
1699   B->mapping    = 0;
1700   B->factor     = 0;
1701   B->assembled  = PETSC_FALSE;
1702 
1703   B->insertmode = NOT_SET_VALUES;
1704   ierr = MPI_Comm_rank(comm,&b->rank);CHKERRQ(ierr);
1705   ierr = MPI_Comm_size(comm,&b->size);CHKERRQ(ierr);
1706 
1707   if (m == PETSC_DECIDE && (d_nnz || o_nnz)) {
1708     SETERRQ(PETSC_ERR_ARG_OUTOFRANGE,"Cannot have PETSC_DECIDE rows but set d_nnz or o_nnz");
1709   }
1710   if (M == PETSC_DECIDE && m == PETSC_DECIDE) {
1711     SETERRQ(PETSC_ERR_ARG_OUTOFRANGE,"either M or m should be specified");
1712   }
1713   if (M != PETSC_DECIDE && m != PETSC_DECIDE) M = PETSC_DECIDE;
1714 
1715   if (M == PETSC_DECIDE) {
1716     work[0] = m; mbs = m/bs;
1717     ierr = MPI_Allreduce(work,sum,1,MPI_INT,MPI_SUM,comm);CHKERRQ(ierr);
1718     M = sum[0]; Mbs = M/bs;
1719   } else { /* M is specified */
1720     Mbs = M/bs;
1721     if (Mbs*bs != M) SETERRQ(PETSC_ERR_ARG_SIZ,"No of global rows must be divisible by blocksize");
1722     mbs = Mbs/b->size + ((Mbs % b->size) > b->rank);
1723     m   = mbs*bs;
1724   }
1725 
1726   if (mbs*bs != m) {
1727     SETERRQ(PETSC_ERR_ARG_SIZ,"No of local rows/cols must be divisible by blocksize");
1728   }
1729 
1730   b->m = m; B->m = m;
1731   b->n = m; B->n = m;
1732   b->N = M; B->N = M;
1733   b->M = M;
1734   B->M = M;
1735   b->bs  = bs;
1736   b->bs2 = bs*bs;
1737   b->mbs = mbs;
1738   b->nbs = mbs;
1739   b->Mbs = Mbs;
1740   b->Nbs = Mbs;
1741 
1742   /* the information in the maps duplicates the information computed below, eventually
1743      we should remove the duplicate information that is not contained in the maps */
1744   ierr = MapCreateMPI(B->comm,m,M,&B->rmap);CHKERRQ(ierr);
1745   ierr = MapCreateMPI(B->comm,m,M,&B->cmap);CHKERRQ(ierr);
1746 
1747   /* build local table of row and column ownerships */
1748   b->rowners = (int*)PetscMalloc(3*(b->size+2)*sizeof(int));CHKPTRQ(b->rowners);
1749   PLogObjectMemory(B,3*(b->size+2)*sizeof(int)+sizeof(struct _p_Mat)+sizeof(Mat_MPISBAIJ));
1750   b->cowners    = b->rowners + b->size + 2;
1751   b->rowners_bs = b->cowners + b->size + 2;
1752   ierr = MPI_Allgather(&mbs,1,MPI_INT,b->rowners+1,1,MPI_INT,comm);CHKERRQ(ierr);
1753   b->rowners[0]    = 0;
1754   for (i=2; i<=b->size; i++) {
1755     b->rowners[i] += b->rowners[i-1];
1756   }
1757   for (i=0; i<=b->size; i++) {
1758     b->rowners_bs[i] = b->rowners[i]*bs;
1759   }
1760   b->rstart    = b->rowners[b->rank];
1761   b->rend      = b->rowners[b->rank+1];
1762   b->rstart_bs = b->rstart * bs;
1763   b->rend_bs   = b->rend * bs;
1764 
1765   b->cstart    = b->rstart;
1766   b->cend      = b->rend;
1767   b->cstart_bs = b->cstart * bs;
1768   b->cend_bs   = b->cend * bs;
1769 
1770 
1771   if (d_nz == PETSC_DEFAULT) d_nz = 5;
1772   ierr = MatCreateSeqSBAIJ(PETSC_COMM_SELF,bs,m,m,d_nz,d_nnz,&b->A);CHKERRQ(ierr);
1773   PLogObjectParent(B,b->A);
1774   if (o_nz == PETSC_DEFAULT) o_nz = 0;
1775   ierr = MatCreateSeqBAIJ(PETSC_COMM_SELF,bs,m,M,o_nz,o_nnz,&b->B);CHKERRQ(ierr);
1776   PLogObjectParent(B,b->B);
1777 
1778   /* build cache for off array entries formed */
1779   ierr = MatStashCreate_Private(B->comm,1,&B->stash);CHKERRQ(ierr);
1780   ierr = MatStashCreate_Private(B->comm,bs,&B->bstash);CHKERRQ(ierr);
1781   b->donotstash  = PETSC_FALSE;
1782   b->colmap      = PETSC_NULL;
1783   b->garray      = PETSC_NULL;
1784   b->roworiented = PETSC_TRUE;
1785 
1786 #if defined(PEYSC_USE_MAT_SINGLE)
1787   /* stuff for MatSetValues_XXX in single precision */
1788   b->lensetvalues     = 0;
1789   b->setvaluescopy    = PETSC_NULL;
1790 #endif
1791 
1792   /* stuff used in block assembly */
1793   b->barray       = 0;
1794 
1795   /* stuff used for matrix vector multiply */
1796   b->lvec         = 0;
1797   b->Mvctx        = 0;
1798 
1799   /* stuff for MatGetRow() */
1800   b->rowindices   = 0;
1801   b->rowvalues    = 0;
1802   b->getrowactive = PETSC_FALSE;
1803 
1804   /* hash table stuff */
1805   b->ht           = 0;
1806   b->hd           = 0;
1807   b->ht_size      = 0;
1808   b->ht_flag      = PETSC_FALSE;
1809   b->ht_fact      = 0;
1810   b->ht_total_ct  = 0;
1811   b->ht_insert_ct = 0;
1812 
1813   *A = B;
1814   ierr = OptionsHasName(PETSC_NULL,"-mat_use_hash_table",&flg);CHKERRQ(ierr);
1815   if (flg) {
1816     double fact = 1.39;
1817     ierr = MatSetOption(B,MAT_USE_HASH_TABLE);CHKERRQ(ierr);
1818     ierr = OptionsGetDouble(PETSC_NULL,"-mat_use_hash_table",&fact,PETSC_NULL);CHKERRQ(ierr);
1819     if (fact <= 1.0) fact = 1.39;
1820     ierr = MatMPIBAIJSetHashTableFactor(B,fact);CHKERRQ(ierr);
1821     PLogInfo(0,"MatCreateMPISBAIJ:Hash table Factor used %5.2f\n",fact);
1822   }
1823   ierr = PetscObjectComposeFunctionDynamic((PetscObject)B,"MatStoreValues_C",
1824                                      "MatStoreValues_MPISBAIJ",
1825                                      MatStoreValues_MPISBAIJ);CHKERRQ(ierr);
1826   ierr = PetscObjectComposeFunctionDynamic((PetscObject)B,"MatRetrieveValues_C",
1827                                      "MatRetrieveValues_MPISBAIJ",
1828                                      MatRetrieveValues_MPISBAIJ);CHKERRQ(ierr);
1829   ierr = PetscObjectComposeFunctionDynamic((PetscObject)B,"MatGetDiagonalBlock_C",
1830                                      "MatGetDiagonalBlock_MPISBAIJ",
1831                                      MatGetDiagonalBlock_MPISBAIJ);CHKERRQ(ierr);
1832   PetscFunctionReturn(0);
1833 }
1834 
1835 
1836 #undef __FUNC__
1837 #define __FUNC__ /*<a name=""></a>*/"MatDuplicate_MPISBAIJ"
1838 static int MatDuplicate_MPISBAIJ(Mat matin,MatDuplicateOption cpvalues,Mat *newmat)
1839 {
1840   Mat         mat;
1841   Mat_MPISBAIJ *a,*oldmat = (Mat_MPISBAIJ*)matin->data;
1842   int         ierr,len=0;
1843   PetscTruth  flg;
1844 
1845   PetscFunctionBegin;
1846   *newmat       = 0;
1847   PetscHeaderCreate(mat,_p_Mat,struct _MatOps,MAT_COOKIE,MATMPISBAIJ,"Mat",matin->comm,MatDestroy,MatView);
1848   PLogObjectCreate(mat);
1849   mat->data         = (void*)(a = PetscNew(Mat_MPISBAIJ));CHKPTRQ(a);
1850   ierr              = PetscMemcpy(mat->ops,&MatOps_Values,sizeof(struct _MatOps));CHKERRQ(ierr);
1851   mat->ops->destroy = MatDestroy_MPISBAIJ;
1852   mat->ops->view    = MatView_MPISBAIJ;
1853   mat->factor       = matin->factor;
1854   mat->assembled    = PETSC_TRUE;
1855   mat->insertmode   = NOT_SET_VALUES;
1856 
1857   a->m = mat->m   = oldmat->m;
1858   a->n = mat->n   = oldmat->n;
1859   a->M = mat->M   = oldmat->M;
1860   a->N = mat->N   = oldmat->N;
1861 
1862   a->bs  = oldmat->bs;
1863   a->bs2 = oldmat->bs2;
1864   a->mbs = oldmat->mbs;
1865   a->nbs = oldmat->nbs;
1866   a->Mbs = oldmat->Mbs;
1867   a->Nbs = oldmat->Nbs;
1868 
1869   a->rstart       = oldmat->rstart;
1870   a->rend         = oldmat->rend;
1871   a->cstart       = oldmat->cstart;
1872   a->cend         = oldmat->cend;
1873   a->size         = oldmat->size;
1874   a->rank         = oldmat->rank;
1875   a->donotstash   = oldmat->donotstash;
1876   a->roworiented  = oldmat->roworiented;
1877   a->rowindices   = 0;
1878   a->rowvalues    = 0;
1879   a->getrowactive = PETSC_FALSE;
1880   a->barray       = 0;
1881   a->rstart_bs    = oldmat->rstart_bs;
1882   a->rend_bs      = oldmat->rend_bs;
1883   a->cstart_bs    = oldmat->cstart_bs;
1884   a->cend_bs      = oldmat->cend_bs;
1885 
1886   /* hash table stuff */
1887   a->ht           = 0;
1888   a->hd           = 0;
1889   a->ht_size      = 0;
1890   a->ht_flag      = oldmat->ht_flag;
1891   a->ht_fact      = oldmat->ht_fact;
1892   a->ht_total_ct  = 0;
1893   a->ht_insert_ct = 0;
1894 
1895 
1896   a->rowners = (int*)PetscMalloc(3*(a->size+2)*sizeof(int));CHKPTRQ(a->rowners);
1897   PLogObjectMemory(mat,3*(a->size+2)*sizeof(int)+sizeof(struct _p_Mat)+sizeof(Mat_MPISBAIJ));
1898   a->cowners    = a->rowners + a->size + 2;
1899   a->rowners_bs = a->cowners + a->size + 2;
1900   ierr = PetscMemcpy(a->rowners,oldmat->rowners,3*(a->size+2)*sizeof(int));CHKERRQ(ierr);
1901   ierr = MatStashCreate_Private(matin->comm,1,&mat->stash);CHKERRQ(ierr);
1902   ierr = MatStashCreate_Private(matin->comm,oldmat->bs,&mat->bstash);CHKERRQ(ierr);
1903   if (oldmat->colmap) {
1904 #if defined (PETSC_USE_CTABLE)
1905   ierr = PetscTableCreateCopy(oldmat->colmap,&a->colmap);CHKERRQ(ierr);
1906 #else
1907     a->colmap = (int*)PetscMalloc((a->Nbs)*sizeof(int));CHKPTRQ(a->colmap);
1908     PLogObjectMemory(mat,(a->Nbs)*sizeof(int));
1909     ierr      = PetscMemcpy(a->colmap,oldmat->colmap,(a->Nbs)*sizeof(int));CHKERRQ(ierr);
1910 #endif
1911   } else a->colmap = 0;
1912   if (oldmat->garray && (len = ((Mat_SeqBAIJ*)(oldmat->B->data))->nbs)) {
1913     a->garray = (int*)PetscMalloc(len*sizeof(int));CHKPTRQ(a->garray);
1914     PLogObjectMemory(mat,len*sizeof(int));
1915     ierr = PetscMemcpy(a->garray,oldmat->garray,len*sizeof(int));CHKERRQ(ierr);
1916   } else a->garray = 0;
1917 
1918   ierr =  VecDuplicate(oldmat->lvec,&a->lvec);CHKERRQ(ierr);
1919   PLogObjectParent(mat,a->lvec);
1920   ierr =  VecScatterCopy(oldmat->Mvctx,&a->Mvctx);CHKERRQ(ierr);
1921 
1922   PLogObjectParent(mat,a->Mvctx);
1923   ierr =  MatDuplicate(oldmat->A,cpvalues,&a->A);CHKERRQ(ierr);
1924   PLogObjectParent(mat,a->A);
1925   ierr =  MatDuplicate(oldmat->B,cpvalues,&a->B);CHKERRQ(ierr);
1926   PLogObjectParent(mat,a->B);
1927   ierr = OptionsHasName(PETSC_NULL,"-help",&flg);CHKERRQ(ierr);
1928   ierr = FListDuplicate(mat->qlist,&matin->qlist);CHKERRQ(ierr);
1929   if (flg) {
1930     ierr = MatPrintHelp(mat);CHKERRQ(ierr);
1931   }
1932   *newmat = mat;
1933   PetscFunctionReturn(0);
1934 }
1935 
1936 #include "petscsys.h"
1937 
1938 #undef __FUNC__
1939 #define __FUNC__ /*<a name=""></a>*/"MatLoad_MPISBAIJ"
1940 int MatLoad_MPISBAIJ(Viewer viewer,MatType type,Mat *newmat)
1941 {
1942   Mat          A;
1943   int          i,nz,ierr,j,rstart,rend,fd;
1944   Scalar       *vals,*buf;
1945   MPI_Comm     comm = ((PetscObject)viewer)->comm;
1946   MPI_Status   status;
1947   int          header[4],rank,size,*rowlengths = 0,M,N,m,*rowners,*browners,maxnz,*cols;
1948   int          *locrowlens,*sndcounts = 0,*procsnz = 0,jj,*mycols,*ibuf;
1949   int          tag = ((PetscObject)viewer)->tag,bs=1,Mbs,mbs,extra_rows;
1950   int          *dlens,*odlens,*mask,*masked1,*masked2,rowcount,odcount;
1951   int          dcount,kmax,k,nzcount,tmp;
1952 
1953   PetscFunctionBegin;
1954   ierr = OptionsGetInt(PETSC_NULL,"-matload_block_size",&bs,PETSC_NULL);CHKERRQ(ierr);
1955 
1956   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
1957   ierr = MPI_Comm_rank(comm,&rank);CHKERRQ(ierr);
1958   if (!rank) {
1959     ierr = ViewerBinaryGetDescriptor(viewer,&fd);CHKERRQ(ierr);
1960     ierr = PetscBinaryRead(fd,(char *)header,4,PETSC_INT);CHKERRQ(ierr);
1961     if (header[0] != MAT_COOKIE) SETERRQ(PETSC_ERR_FILE_UNEXPECTED,"not matrix object");
1962     if (header[3] < 0) {
1963       SETERRQ(PETSC_ERR_FILE_UNEXPECTED,"Matrix stored in special format, cannot load as MPISBAIJ");
1964     }
1965   }
1966 
1967   ierr = MPI_Bcast(header+1,3,MPI_INT,0,comm);CHKERRQ(ierr);
1968   M = header[1]; N = header[2];
1969 
1970   if (M != N) SETERRQ(PETSC_ERR_SUP,"Can only do square matrices");
1971 
1972   /*
1973      This code adds extra rows to make sure the number of rows is
1974      divisible by the blocksize
1975   */
1976   Mbs        = M/bs;
1977   extra_rows = bs - M + bs*(Mbs);
1978   if (extra_rows == bs) extra_rows = 0;
1979   else                  Mbs++;
1980   if (extra_rows &&!rank) {
1981     PLogInfo(0,"MatLoad_MPISBAIJ:Padding loaded matrix to match blocksize\n");
1982   }
1983 
1984   /* determine ownership of all rows */
1985   mbs = Mbs/size + ((Mbs % size) > rank);
1986   m   = mbs * bs;
1987   rowners = (int*)PetscMalloc(2*(size+2)*sizeof(int));CHKPTRQ(rowners);
1988   browners = rowners + size + 1;
1989   ierr = MPI_Allgather(&mbs,1,MPI_INT,rowners+1,1,MPI_INT,comm);CHKERRQ(ierr);
1990   rowners[0] = 0;
1991   for (i=2; i<=size; i++) rowners[i] += rowners[i-1];
1992   for (i=0; i<=size;  i++) browners[i] = rowners[i]*bs;
1993   rstart = rowners[rank];
1994   rend   = rowners[rank+1];
1995 
1996   /* distribute row lengths to all processors */
1997   locrowlens = (int*)PetscMalloc((rend-rstart)*bs*sizeof(int));CHKPTRQ(locrowlens);
1998   if (!rank) {
1999     rowlengths = (int*)PetscMalloc((M+extra_rows)*sizeof(int));CHKPTRQ(rowlengths);
2000     ierr = PetscBinaryRead(fd,rowlengths,M,PETSC_INT);CHKERRQ(ierr);
2001     for (i=0; i<extra_rows; i++) rowlengths[M+i] = 1;
2002     sndcounts = (int*)PetscMalloc(size*sizeof(int));CHKPTRQ(sndcounts);
2003     for (i=0; i<size; i++) sndcounts[i] = browners[i+1] - browners[i];
2004     ierr = MPI_Scatterv(rowlengths,sndcounts,browners,MPI_INT,locrowlens,(rend-rstart)*bs,MPI_INT,0,comm);CHKERRQ(ierr);
2005     ierr = PetscFree(sndcounts);CHKERRQ(ierr);
2006   } else {
2007     ierr = MPI_Scatterv(0,0,0,MPI_INT,locrowlens,(rend-rstart)*bs,MPI_INT,0,comm);CHKERRQ(ierr);
2008   }
2009 
2010   if (!rank) {   /* procs[0] */
2011     /* calculate the number of nonzeros on each processor */
2012     procsnz = (int*)PetscMalloc(size*sizeof(int));CHKPTRQ(procsnz);
2013     ierr    = PetscMemzero(procsnz,size*sizeof(int));CHKERRQ(ierr);
2014     for (i=0; i<size; i++) {
2015       for (j=rowners[i]*bs; j< rowners[i+1]*bs; j++) {
2016         procsnz[i] += rowlengths[j];
2017       }
2018     }
2019     ierr = PetscFree(rowlengths);CHKERRQ(ierr);
2020 
2021     /* determine max buffer needed and allocate it */
2022     maxnz = 0;
2023     for (i=0; i<size; i++) {
2024       maxnz = PetscMax(maxnz,procsnz[i]);
2025     }
2026     cols = (int*)PetscMalloc(maxnz*sizeof(int));CHKPTRQ(cols);
2027 
2028     /* read in my part of the matrix column indices  */
2029     nz = procsnz[0];
2030     ibuf = (int*)PetscMalloc(nz*sizeof(int));CHKPTRQ(ibuf);
2031     mycols = ibuf;
2032     if (size == 1)  nz -= extra_rows;
2033     ierr = PetscBinaryRead(fd,mycols,nz,PETSC_INT);CHKERRQ(ierr);
2034     if (size == 1)  for (i=0; i< extra_rows; i++) { mycols[nz+i] = M+i; }
2035 
2036     /* read in every ones (except the last) and ship off */
2037     for (i=1; i<size-1; i++) {
2038       nz   = procsnz[i];
2039       ierr = PetscBinaryRead(fd,cols,nz,PETSC_INT);CHKERRQ(ierr);
2040       ierr = MPI_Send(cols,nz,MPI_INT,i,tag,comm);CHKERRQ(ierr);
2041     }
2042     /* read in the stuff for the last proc */
2043     if (size != 1) {
2044       nz   = procsnz[size-1] - extra_rows;  /* the extra rows are not on the disk */
2045       ierr = PetscBinaryRead(fd,cols,nz,PETSC_INT);CHKERRQ(ierr);
2046       for (i=0; i<extra_rows; i++) cols[nz+i] = M+i;
2047       ierr = MPI_Send(cols,nz+extra_rows,MPI_INT,size-1,tag,comm);CHKERRQ(ierr);
2048     }
2049     ierr = PetscFree(cols);CHKERRQ(ierr);
2050   } else {  /* procs[i], i>0 */
2051     /* determine buffer space needed for message */
2052     nz = 0;
2053     for (i=0; i<m; i++) {
2054       nz += locrowlens[i];
2055     }
2056     ibuf   = (int*)PetscMalloc(nz*sizeof(int));CHKPTRQ(ibuf);
2057     mycols = ibuf;
2058     /* receive message of column indices*/
2059     ierr = MPI_Recv(mycols,nz,MPI_INT,0,tag,comm,&status);CHKERRQ(ierr);
2060     ierr = MPI_Get_count(&status,MPI_INT,&maxnz);CHKERRQ(ierr);
2061     if (maxnz != nz) SETERRQ(PETSC_ERR_FILE_UNEXPECTED,"something is wrong with file");
2062   }
2063 
2064   /* loop over local rows, determining number of off diagonal entries */
2065   dlens  = (int*)PetscMalloc(2*(rend-rstart+1)*sizeof(int));CHKPTRQ(dlens);
2066   odlens = dlens + (rend-rstart);
2067   mask   = (int*)PetscMalloc(3*Mbs*sizeof(int));CHKPTRQ(mask);
2068   ierr   = PetscMemzero(mask,3*Mbs*sizeof(int));CHKERRQ(ierr);
2069   masked1 = mask    + Mbs;
2070   masked2 = masked1 + Mbs;
2071   rowcount = 0; nzcount = 0;
2072   for (i=0; i<mbs; i++) {
2073     dcount  = 0;
2074     odcount = 0;
2075     for (j=0; j<bs; j++) {
2076       kmax = locrowlens[rowcount];
2077       for (k=0; k<kmax; k++) {
2078         tmp = mycols[nzcount++]/bs; /* block col. index */
2079         if (!mask[tmp]) {
2080           mask[tmp] = 1;
2081           if (tmp < rstart || tmp >= rend) masked2[odcount++] = tmp; /* entry in off-diag portion */
2082           else masked1[dcount++] = tmp; /* entry in diag portion */
2083         }
2084       }
2085       rowcount++;
2086     }
2087 
2088     dlens[i]  = dcount;  /* d_nzz[i] */
2089     odlens[i] = odcount; /* o_nzz[i] */
2090 
2091     /* zero out the mask elements we set */
2092     for (j=0; j<dcount; j++) mask[masked1[j]] = 0;
2093     for (j=0; j<odcount; j++) mask[masked2[j]] = 0;
2094   }
2095 
2096   /* create our matrix */
2097   ierr = MatCreateMPISBAIJ(comm,bs,m,m,PETSC_DETERMINE,PETSC_DETERMINE,0,dlens,0,odlens,newmat);
2098   CHKERRQ(ierr);
2099   A = *newmat;
2100   MatSetOption(A,MAT_COLUMNS_SORTED);
2101 
2102   if (!rank) {
2103     buf = (Scalar*)PetscMalloc(maxnz*sizeof(Scalar));CHKPTRQ(buf);
2104     /* read in my part of the matrix numerical values  */
2105     nz = procsnz[0];
2106     vals = buf;
2107     mycols = ibuf;
2108     if (size == 1)  nz -= extra_rows;
2109     ierr = PetscBinaryRead(fd,vals,nz,PETSC_SCALAR);CHKERRQ(ierr);
2110     if (size == 1)  for (i=0; i< extra_rows; i++) { vals[nz+i] = 1.0; }
2111 
2112     /* insert into matrix */
2113     jj      = rstart*bs;
2114     for (i=0; i<m; i++) {
2115       ierr = MatSetValues(A,1,&jj,locrowlens[i],mycols,vals,INSERT_VALUES);CHKERRQ(ierr);
2116       mycols += locrowlens[i];
2117       vals   += locrowlens[i];
2118       jj++;
2119     }
2120 
2121     /* read in other processors (except the last one) and ship out */
2122     for (i=1; i<size-1; i++) {
2123       nz   = procsnz[i];
2124       vals = buf;
2125       ierr = PetscBinaryRead(fd,vals,nz,PETSC_SCALAR);CHKERRQ(ierr);
2126       ierr = MPI_Send(vals,nz,MPIU_SCALAR,i,A->tag,comm);CHKERRQ(ierr);
2127     }
2128     /* the last proc */
2129     if (size != 1){
2130       nz   = procsnz[i] - extra_rows;
2131       vals = buf;
2132       ierr = PetscBinaryRead(fd,vals,nz,PETSC_SCALAR);CHKERRQ(ierr);
2133       for (i=0; i<extra_rows; i++) vals[nz+i] = 1.0;
2134       ierr = MPI_Send(vals,nz+extra_rows,MPIU_SCALAR,size-1,A->tag,comm);CHKERRQ(ierr);
2135     }
2136     ierr = PetscFree(procsnz);CHKERRQ(ierr);
2137 
2138   } else {
2139     /* receive numeric values */
2140     buf = (Scalar*)PetscMalloc(nz*sizeof(Scalar));CHKPTRQ(buf);
2141 
2142     /* receive message of values*/
2143     vals   = buf;
2144     mycols = ibuf;
2145     ierr   = MPI_Recv(vals,nz,MPIU_SCALAR,0,A->tag,comm,&status);CHKERRQ(ierr);
2146     ierr   = MPI_Get_count(&status,MPIU_SCALAR,&maxnz);CHKERRQ(ierr);
2147     if (maxnz != nz) SETERRQ(PETSC_ERR_FILE_UNEXPECTED,"something is wrong with file");
2148 
2149     /* insert into matrix */
2150     jj      = rstart*bs;
2151     for (i=0; i<m; i++) {
2152       ierr    = MatSetValues_MPISBAIJ(A,1,&jj,locrowlens[i],mycols,vals,INSERT_VALUES);CHKERRQ(ierr);
2153       mycols += locrowlens[i];
2154       vals   += locrowlens[i];
2155       jj++;
2156     }
2157   }
2158 
2159   ierr = PetscFree(locrowlens);CHKERRQ(ierr);
2160   ierr = PetscFree(buf);CHKERRQ(ierr);
2161   ierr = PetscFree(ibuf);CHKERRQ(ierr);
2162   ierr = PetscFree(rowners);CHKERRQ(ierr);
2163   ierr = PetscFree(dlens);CHKERRQ(ierr);
2164   ierr = PetscFree(mask);CHKERRQ(ierr);
2165   ierr = MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
2166   ierr = MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
2167   PetscFunctionReturn(0);
2168 }
2169 
2170 #undef __FUNC__
2171 #define __FUNC__ /*<a name=""></a>*/"MatMPISBAIJSetHashTableFactor"
2172 /*@
2173    MatMPISBAIJSetHashTableFactor - Sets the factor required to compute the size of the HashTable.
2174 
2175    Input Parameters:
2176 .  mat  - the matrix
2177 .  fact - factor
2178 
2179    Collective on Mat
2180 
2181    Level: advanced
2182 
2183   Notes:
2184    This can also be set by the command line option: -mat_use_hash_table fact
2185 
2186 .keywords: matrix, hashtable, factor, HT
2187 
2188 .seealso: MatSetOption()
2189 @*/
2190 int MatMPISBAIJSetHashTableFactor(Mat mat,PetscReal fact)
2191 {
2192   PetscFunctionBegin;
2193   SETERRQ(1,"Function not yet written for SBAIJ format");
2194   /* PetscFunctionReturn(0); */
2195 }
2196 
2197 #undef __FUNC__
2198 #define __FUNC__ /*<a name=""></a>*/"MatGetRowMax_MPISBAIJ"
2199 int MatGetRowMax_MPISBAIJ(Mat A,Vec v)
2200 {
2201   Mat_MPISBAIJ *a = (Mat_MPISBAIJ*)A->data;
2202   int          ierr;
2203 
2204   PetscFunctionBegin;
2205   /* if (a->M != a->N) SETERRQ(PETSC_ERR_SUP,"Supports only square matrix where A->A is diag block"); */
2206   ierr = MatGetRowMax(a->A,v);CHKERRQ(ierr);
2207   /* printf("GetRowMax is called\n"); */
2208   PetscFunctionReturn(0);
2209 }
2210