xref: /petsc/src/mat/impls/baij/seq/baijfact3.c (revision f3fe499b4cc4d64bf04aa4f5e4963dcc4eb56541)
1 #define PETSCMAT_DLL
2 
3 /*
4     Factorization code for BAIJ format.
5 */
6 #include "../src/mat/impls/baij/seq/baij.h"
7 #include "../src/mat/blockinvert.h"
8 
9 #undef __FUNCT__
10 #define __FUNCT__ "MatSeqBAIJSetNumericFactorization"
11 /*
12    This is used to set the numeric factorization for both LU and ILU symbolic factorization
13 */
14 PetscErrorCode MatSeqBAIJSetNumericFactorization(Mat fact,PetscTruth natural)
15 {
16   PetscFunctionBegin;
17   if(natural){
18     switch (fact->rmap->bs){
19     case 1:
20       fact->ops->lufactornumeric = MatLUFactorNumeric_SeqBAIJ_1;
21       break;
22     case 2:
23       fact->ops->lufactornumeric = MatLUFactorNumeric_SeqBAIJ_2_NaturalOrdering;
24       break;
25     case 3:
26       fact->ops->lufactornumeric = MatLUFactorNumeric_SeqBAIJ_3_NaturalOrdering;
27       break;
28     case 4:
29       fact->ops->lufactornumeric = MatLUFactorNumeric_SeqBAIJ_4_NaturalOrdering;
30       break;
31     case 5:
32        fact->ops->lufactornumeric = MatLUFactorNumeric_SeqBAIJ_5_NaturalOrdering;
33        break;
34     case 6:
35       fact->ops->lufactornumeric = MatLUFactorNumeric_SeqBAIJ_6_NaturalOrdering;
36       break;
37     case 7:
38       fact->ops->lufactornumeric = MatLUFactorNumeric_SeqBAIJ_7_NaturalOrdering;
39       break;
40     case 15:
41       fact->ops->lufactornumeric = MatLUFactorNumeric_SeqBAIJ_15_NaturalOrdering;
42       break;
43     default:
44       fact->ops->lufactornumeric = MatLUFactorNumeric_SeqBAIJ_N;
45       break;
46     }
47   } else {
48     switch (fact->rmap->bs){
49     case 1:
50       fact->ops->lufactornumeric = MatLUFactorNumeric_SeqBAIJ_1;
51       break;
52     case 2:
53       fact->ops->lufactornumeric = MatLUFactorNumeric_SeqBAIJ_2;
54       break;
55     case 3:
56       fact->ops->lufactornumeric = MatLUFactorNumeric_SeqBAIJ_3;
57       break;
58     case 4:
59       fact->ops->lufactornumeric = MatLUFactorNumeric_SeqBAIJ_4;
60       break;
61     case 5:
62       fact->ops->lufactornumeric = MatLUFactorNumeric_SeqBAIJ_5;
63       break;
64     case 6:
65       fact->ops->lufactornumeric = MatLUFactorNumeric_SeqBAIJ_6;
66       break;
67     case 7:
68       fact->ops->lufactornumeric = MatLUFactorNumeric_SeqBAIJ_7;
69       break;
70     default:
71       fact->ops->lufactornumeric = MatLUFactorNumeric_SeqBAIJ_N;
72       break;
73     }
74   }
75   PetscFunctionReturn(0);
76 }
77 
78 PetscErrorCode MatSeqBAIJSetNumericFactorization_inplace(Mat inA,PetscTruth natural)
79 {
80   PetscFunctionBegin;
81   if (natural) {
82     switch (inA->rmap->bs) {
83     case 1:
84       inA->ops->lufactornumeric = MatLUFactorNumeric_SeqBAIJ_1_inplace;
85       break;
86     case 2:
87       inA->ops->lufactornumeric = MatLUFactorNumeric_SeqBAIJ_2_NaturalOrdering_inplace;
88       break;
89     case 3:
90       inA->ops->lufactornumeric = MatLUFactorNumeric_SeqBAIJ_3_NaturalOrdering_inplace;
91       break;
92     case 4:
93 #if defined(PETSC_USE_SCALAR_MAT_SINGLE)
94       {
95         PetscTruth  sse_enabled_local;
96         PetscErrorCode ierr;
97         ierr = PetscSSEIsEnabled(inA->comm,&sse_enabled_local,PETSC_NULL);CHKERRQ(ierr);
98         if (sse_enabled_local) {
99 #  if defined(PETSC_HAVE_SSE)
100           int i,*AJ=a->j,nz=a->nz,n=a->mbs;
101           if (n==(unsigned short)n) {
102             unsigned short *aj=(unsigned short *)AJ;
103             for (i=0;i<nz;i++) {
104               aj[i] = (unsigned short)AJ[i];
105             }
106             inA->ops->setunfactored   = MatSetUnfactored_SeqBAIJ_4_NaturalOrdering_SSE_usj;
107             inA->ops->lufactornumeric = MatLUFactorNumeric_SeqBAIJ_4_NaturalOrdering_SSE_usj;
108             ierr = PetscInfo(inA,"Using special SSE, in-place natural ordering, ushort j index factor BS=4\n");CHKERRQ(ierr);
109           } else {
110         /* Scale the column indices for easier indexing in MatSolve. */
111 /*            for (i=0;i<nz;i++) { */
112 /*              AJ[i] = AJ[i]*4; */
113 /*            } */
114             inA->ops->setunfactored   = MatSetUnfactored_SeqBAIJ_4_NaturalOrdering_SSE;
115             inA->ops->lufactornumeric = MatLUFactorNumeric_SeqBAIJ_4_NaturalOrdering_SSE;
116             ierr = PetscInfo(inA,"Using special SSE, in-place natural ordering, int j index factor BS=4\n");CHKERRQ(ierr);
117           }
118 #  else
119         /* This should never be reached.  If so, problem in PetscSSEIsEnabled. */
120           SETERRQ(PETSC_COMM_SELF,PETSC_ERR_SUP,"SSE Hardware unavailable");
121 #  endif
122         } else {
123           inA->ops->lufactornumeric = MatLUFactorNumeric_SeqBAIJ_4_NaturalOrdering_inplace;
124         }
125       }
126 #else
127       inA->ops->lufactornumeric = MatLUFactorNumeric_SeqBAIJ_4_NaturalOrdering_inplace;
128 #endif
129       break;
130     case 5:
131       inA->ops->lufactornumeric = MatLUFactorNumeric_SeqBAIJ_5_NaturalOrdering_inplace;
132       break;
133     case 6:
134       inA->ops->lufactornumeric = MatLUFactorNumeric_SeqBAIJ_6_NaturalOrdering_inplace;
135       break;
136     case 7:
137       inA->ops->lufactornumeric = MatLUFactorNumeric_SeqBAIJ_7_NaturalOrdering_inplace;
138       break;
139     default:
140       inA->ops->lufactornumeric = MatLUFactorNumeric_SeqBAIJ_N_inplace;
141       break;
142     }
143   } else {
144     switch (inA->rmap->bs) {
145     case 1:
146       inA->ops->lufactornumeric = MatLUFactorNumeric_SeqBAIJ_1_inplace;
147       break;
148     case 2:
149       inA->ops->lufactornumeric = MatLUFactorNumeric_SeqBAIJ_2_inplace;
150       break;
151     case 3:
152       inA->ops->lufactornumeric = MatLUFactorNumeric_SeqBAIJ_3_inplace;
153       break;
154     case 4:
155       inA->ops->lufactornumeric = MatLUFactorNumeric_SeqBAIJ_4_inplace;
156       break;
157     case 5:
158       inA->ops->lufactornumeric = MatLUFactorNumeric_SeqBAIJ_5_inplace;
159       break;
160     case 6:
161       inA->ops->lufactornumeric = MatLUFactorNumeric_SeqBAIJ_6_inplace;
162       break;
163     case 7:
164       inA->ops->lufactornumeric = MatLUFactorNumeric_SeqBAIJ_7_inplace;
165       break;
166     default:
167       inA->ops->lufactornumeric = MatLUFactorNumeric_SeqBAIJ_N_inplace;
168       break;
169     }
170   }
171   PetscFunctionReturn(0);
172 }
173 
174 /*
175     The symbolic factorization code is identical to that for AIJ format,
176   except for very small changes since this is now a SeqBAIJ datastructure.
177   NOT good code reuse.
178 */
179 #include "petscbt.h"
180 #include "../src/mat/utils/freespace.h"
181 
182 #undef __FUNCT__
183 #define __FUNCT__ "MatLUFactorSymbolic_SeqBAIJ"
184 PetscErrorCode MatLUFactorSymbolic_SeqBAIJ(Mat B,Mat A,IS isrow,IS iscol,const MatFactorInfo *info)
185 {
186   Mat_SeqBAIJ        *a = (Mat_SeqBAIJ*)A->data,*b;
187   PetscInt           n=a->mbs,bs = A->rmap->bs,bs2=a->bs2;
188   PetscTruth         row_identity,col_identity,both_identity;
189   IS                 isicol;
190   PetscErrorCode     ierr;
191   const PetscInt     *r,*ic;
192   PetscInt           i,*ai=a->i,*aj=a->j;
193   PetscInt           *bi,*bj,*ajtmp;
194   PetscInt           *bdiag,row,nnz,nzi,reallocs=0,nzbd,*im;
195   PetscReal          f;
196   PetscInt           nlnk,*lnk,k,**bi_ptr;
197   PetscFreeSpaceList free_space=PETSC_NULL,current_space=PETSC_NULL;
198   PetscBT            lnkbt;
199 
200   PetscFunctionBegin;
201   if (A->rmap->N != A->cmap->N) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONG,"matrix must be square");
202   if (bs>1){  /* check shifttype */
203     if (info->shifttype == MAT_SHIFT_NONZERO || info->shifttype == MAT_SHIFT_POSITIVE_DEFINITE)
204       SETERRQ(PETSC_COMM_SELF,PETSC_ERR_SUP,"Only MAT_SHIFT_NONE and MAT_SHIFT_INBLOCKS are supported for BAIJ matrix");
205   }
206 
207   ierr = ISInvertPermutation(iscol,PETSC_DECIDE,&isicol);CHKERRQ(ierr);
208   ierr = ISGetIndices(isrow,&r);CHKERRQ(ierr);
209   ierr = ISGetIndices(isicol,&ic);CHKERRQ(ierr);
210 
211   /* get new row and diagonal pointers, must be allocated separately because they will be given to the Mat_SeqAIJ and freed separately */
212   ierr = PetscMalloc((n+1)*sizeof(PetscInt),&bi);CHKERRQ(ierr);
213   ierr = PetscMalloc((n+1)*sizeof(PetscInt),&bdiag);CHKERRQ(ierr);
214   bi[0] = bdiag[0] = 0;
215 
216   /* linked list for storing column indices of the active row */
217   nlnk = n + 1;
218   ierr = PetscLLCreate(n,n,nlnk,lnk,lnkbt);CHKERRQ(ierr);
219 
220   ierr = PetscMalloc2(n+1,PetscInt**,&bi_ptr,n+1,PetscInt,&im);CHKERRQ(ierr);
221 
222   /* initial FreeSpace size is f*(ai[n]+1) */
223   f = info->fill;
224   ierr = PetscFreeSpaceGet((PetscInt)(f*(ai[n]+1)),&free_space);CHKERRQ(ierr);
225   current_space = free_space;
226 
227   for (i=0; i<n; i++) {
228     /* copy previous fill into linked list */
229     nzi = 0;
230     nnz = ai[r[i]+1] - ai[r[i]];
231     if (!nnz) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_MAT_LU_ZRPVT,"Empty row in matrix: row in original ordering %D in permuted ordering %D",r[i],i);
232     ajtmp = aj + ai[r[i]];
233     ierr = PetscLLAddPerm(nnz,ajtmp,ic,n,nlnk,lnk,lnkbt);CHKERRQ(ierr);
234     nzi += nlnk;
235 
236     /* add pivot rows into linked list */
237     row = lnk[n];
238     while (row < i) {
239       nzbd    = bdiag[row] + 1; /* num of entries in the row with column index <= row */
240       ajtmp   = bi_ptr[row] + nzbd; /* points to the entry next to the diagonal */
241       ierr = PetscLLAddSortedLU(ajtmp,row,nlnk,lnk,lnkbt,i,nzbd,im);CHKERRQ(ierr);
242       nzi += nlnk;
243       row  = lnk[row];
244     }
245     bi[i+1] = bi[i] + nzi;
246     im[i]   = nzi;
247 
248     /* mark bdiag */
249     nzbd = 0;
250     nnz  = nzi;
251     k    = lnk[n];
252     while (nnz-- && k < i){
253       nzbd++;
254       k = lnk[k];
255     }
256     bdiag[i] = nzbd; /* note : bdaig[i] = nnzL as input for PetscFreeSpaceContiguous_LU() */
257 
258     /* if free space is not available, make more free space */
259     if (current_space->local_remaining<nzi) {
260       nnz = 2*(n - i)*nzi; /* estimated and max additional space needed */
261       ierr = PetscFreeSpaceGet(nnz,&current_space);CHKERRQ(ierr);
262       reallocs++;
263     }
264 
265     /* copy data into free space, then initialize lnk */
266     ierr = PetscLLClean(n,n,nzi,lnk,current_space->array,lnkbt);CHKERRQ(ierr);
267     bi_ptr[i] = current_space->array;
268     current_space->array           += nzi;
269     current_space->local_used      += nzi;
270     current_space->local_remaining -= nzi;
271   }
272 #if defined(PETSC_USE_INFO)
273   if (ai[n] != 0) {
274     PetscReal af = ((PetscReal)(bdiag[0]+1))/((PetscReal)ai[n]);
275     ierr = PetscInfo3(A,"Reallocs %D Fill ratio:given %G needed %G\n",reallocs,f,af);CHKERRQ(ierr);
276     ierr = PetscInfo1(A,"Run with -pc_factor_fill %G or use \n",af);CHKERRQ(ierr);
277     ierr = PetscInfo1(A,"PCFactorSetFill(pc,%G);\n",af);CHKERRQ(ierr);
278     ierr = PetscInfo(A,"for best performance.\n");CHKERRQ(ierr);
279   } else {
280     ierr = PetscInfo(A,"Empty matrix\n");CHKERRQ(ierr);
281   }
282 #endif
283 
284   ierr = ISRestoreIndices(isrow,&r);CHKERRQ(ierr);
285   ierr = ISRestoreIndices(isicol,&ic);CHKERRQ(ierr);
286 
287   /* destroy list of free space and other temporary array(s) */
288   ierr = PetscMalloc((bi[n]+1)*sizeof(PetscInt),&bj);CHKERRQ(ierr);
289   ierr = PetscFreeSpaceContiguous_LU(&free_space,bj,n,bi,bdiag);CHKERRQ(ierr);
290   ierr = PetscLLDestroy(lnk,lnkbt);CHKERRQ(ierr);
291   ierr = PetscFree2(bi_ptr,im);CHKERRQ(ierr);
292 
293   /* put together the new matrix */
294   ierr = MatSeqBAIJSetPreallocation_SeqBAIJ(B,bs,MAT_SKIP_ALLOCATION,PETSC_NULL);CHKERRQ(ierr);
295   ierr = PetscLogObjectParent(B,isicol);CHKERRQ(ierr);
296   b    = (Mat_SeqBAIJ*)(B)->data;
297   b->free_a       = PETSC_TRUE;
298   b->free_ij      = PETSC_TRUE;
299   b->singlemalloc = PETSC_FALSE;
300   ierr          = PetscMalloc((bdiag[0]+1)*sizeof(MatScalar)*bs2,&b->a);CHKERRQ(ierr);
301   b->j          = bj;
302   b->i          = bi;
303   b->diag       = bdiag;
304   b->free_diag  = PETSC_TRUE;
305   b->ilen       = 0;
306   b->imax       = 0;
307   b->row        = isrow;
308   b->col        = iscol;
309   b->pivotinblocks = (info->pivotinblocks) ? PETSC_TRUE : PETSC_FALSE;
310   ierr          = PetscObjectReference((PetscObject)isrow);CHKERRQ(ierr);
311   ierr          = PetscObjectReference((PetscObject)iscol);CHKERRQ(ierr);
312   b->icol       = isicol;
313   ierr = PetscMalloc((bs*n+bs)*sizeof(PetscScalar),&b->solve_work);CHKERRQ(ierr);
314   ierr = PetscLogObjectMemory(B,(bdiag[0]+1)*(sizeof(PetscInt)+sizeof(PetscScalar)*bs2));CHKERRQ(ierr);
315 
316   b->maxnz = b->nz = bdiag[0]+1;
317   B->factortype            =  MAT_FACTOR_LU;
318   B->info.factor_mallocs   = reallocs;
319   B->info.fill_ratio_given = f;
320 
321   if (ai[n] != 0) {
322     B->info.fill_ratio_needed = ((PetscReal)(bdiag[0]+1))/((PetscReal)ai[n]);
323   } else {
324     B->info.fill_ratio_needed = 0.0;
325   }
326 
327   ierr = ISIdentity(isrow,&row_identity);CHKERRQ(ierr);
328   ierr = ISIdentity(iscol,&col_identity);CHKERRQ(ierr);
329   both_identity = (PetscTruth) (row_identity && col_identity);
330   ierr = MatSeqBAIJSetNumericFactorization(B,both_identity);CHKERRQ(ierr);
331   PetscFunctionReturn(0);
332  }
333 
334 #undef __FUNCT__
335 #define __FUNCT__ "MatLUFactorSymbolic_SeqBAIJ_inplace"
336 PetscErrorCode MatLUFactorSymbolic_SeqBAIJ_inplace(Mat B,Mat A,IS isrow,IS iscol,const MatFactorInfo *info)
337 {
338   Mat_SeqBAIJ        *a = (Mat_SeqBAIJ*)A->data,*b;
339   PetscInt           n=a->mbs,bs = A->rmap->bs,bs2=a->bs2;
340   PetscTruth         row_identity,col_identity,both_identity;
341   IS                 isicol;
342   PetscErrorCode     ierr;
343   const PetscInt     *r,*ic;
344   PetscInt           i,*ai=a->i,*aj=a->j;
345   PetscInt           *bi,*bj,*ajtmp;
346   PetscInt           *bdiag,row,nnz,nzi,reallocs=0,nzbd,*im;
347   PetscReal          f;
348   PetscInt           nlnk,*lnk,k,**bi_ptr;
349   PetscFreeSpaceList free_space=PETSC_NULL,current_space=PETSC_NULL;
350   PetscBT            lnkbt;
351 
352   PetscFunctionBegin;
353   if (A->rmap->N != A->cmap->N) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONG,"matrix must be square");
354   ierr = ISInvertPermutation(iscol,PETSC_DECIDE,&isicol);CHKERRQ(ierr);
355   ierr = ISGetIndices(isrow,&r);CHKERRQ(ierr);
356   ierr = ISGetIndices(isicol,&ic);CHKERRQ(ierr);
357 
358   /* get new row and diagonal pointers, must be allocated separately because they will be given to the Mat_SeqAIJ and freed separately */
359   ierr = PetscMalloc((n+1)*sizeof(PetscInt),&bi);CHKERRQ(ierr);
360   ierr = PetscMalloc((n+1)*sizeof(PetscInt),&bdiag);CHKERRQ(ierr);
361 
362   bi[0] = bdiag[0] = 0;
363 
364   /* linked list for storing column indices of the active row */
365   nlnk = n + 1;
366   ierr = PetscLLCreate(n,n,nlnk,lnk,lnkbt);CHKERRQ(ierr);
367 
368   ierr = PetscMalloc2(n+1,PetscInt**,&bi_ptr,n+1,PetscInt,&im);CHKERRQ(ierr);
369 
370   /* initial FreeSpace size is f*(ai[n]+1) */
371   f = info->fill;
372   ierr = PetscFreeSpaceGet((PetscInt)(f*(ai[n]+1)),&free_space);CHKERRQ(ierr);
373   current_space = free_space;
374 
375   for (i=0; i<n; i++) {
376     /* copy previous fill into linked list */
377     nzi = 0;
378     nnz = ai[r[i]+1] - ai[r[i]];
379     if (!nnz) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_MAT_LU_ZRPVT,"Empty row in matrix: row in original ordering %D in permuted ordering %D",r[i],i);
380     ajtmp = aj + ai[r[i]];
381     ierr = PetscLLAddPerm(nnz,ajtmp,ic,n,nlnk,lnk,lnkbt);CHKERRQ(ierr);
382     nzi += nlnk;
383 
384     /* add pivot rows into linked list */
385     row = lnk[n];
386     while (row < i) {
387       nzbd    = bdiag[row] - bi[row] + 1; /* num of entries in the row with column index <= row */
388       ajtmp   = bi_ptr[row] + nzbd; /* points to the entry next to the diagonal */
389       ierr = PetscLLAddSortedLU(ajtmp,row,nlnk,lnk,lnkbt,i,nzbd,im);CHKERRQ(ierr);
390       nzi += nlnk;
391       row  = lnk[row];
392     }
393     bi[i+1] = bi[i] + nzi;
394     im[i]   = nzi;
395 
396     /* mark bdiag */
397     nzbd = 0;
398     nnz  = nzi;
399     k    = lnk[n];
400     while (nnz-- && k < i){
401       nzbd++;
402       k = lnk[k];
403     }
404     bdiag[i] = bi[i] + nzbd;
405 
406     /* if free space is not available, make more free space */
407     if (current_space->local_remaining<nzi) {
408       nnz = (n - i)*nzi; /* estimated and max additional space needed */
409       ierr = PetscFreeSpaceGet(nnz,&current_space);CHKERRQ(ierr);
410       reallocs++;
411     }
412 
413     /* copy data into free space, then initialize lnk */
414     ierr = PetscLLClean(n,n,nzi,lnk,current_space->array,lnkbt);CHKERRQ(ierr);
415     bi_ptr[i] = current_space->array;
416     current_space->array           += nzi;
417     current_space->local_used      += nzi;
418     current_space->local_remaining -= nzi;
419   }
420 #if defined(PETSC_USE_INFO)
421   if (ai[n] != 0) {
422     PetscReal af = ((PetscReal)bi[n])/((PetscReal)ai[n]);
423     ierr = PetscInfo3(A,"Reallocs %D Fill ratio:given %G needed %G\n",reallocs,f,af);CHKERRQ(ierr);
424     ierr = PetscInfo1(A,"Run with -pc_factor_fill %G or use \n",af);CHKERRQ(ierr);
425     ierr = PetscInfo1(A,"PCFactorSetFill(pc,%G);\n",af);CHKERRQ(ierr);
426     ierr = PetscInfo(A,"for best performance.\n");CHKERRQ(ierr);
427   } else {
428     ierr = PetscInfo(A,"Empty matrix\n");CHKERRQ(ierr);
429   }
430 #endif
431 
432   ierr = ISRestoreIndices(isrow,&r);CHKERRQ(ierr);
433   ierr = ISRestoreIndices(isicol,&ic);CHKERRQ(ierr);
434 
435   /* destroy list of free space and other temporary array(s) */
436   ierr = PetscMalloc((bi[n]+1)*sizeof(PetscInt),&bj);CHKERRQ(ierr);
437   ierr = PetscFreeSpaceContiguous(&free_space,bj);CHKERRQ(ierr);
438   ierr = PetscLLDestroy(lnk,lnkbt);CHKERRQ(ierr);
439   ierr = PetscFree2(bi_ptr,im);CHKERRQ(ierr);
440 
441   /* put together the new matrix */
442   ierr = MatSeqBAIJSetPreallocation_SeqBAIJ(B,bs,MAT_SKIP_ALLOCATION,PETSC_NULL);CHKERRQ(ierr);
443   ierr = PetscLogObjectParent(B,isicol);CHKERRQ(ierr);
444   b    = (Mat_SeqBAIJ*)(B)->data;
445   b->free_a       = PETSC_TRUE;
446   b->free_ij      = PETSC_TRUE;
447   b->singlemalloc = PETSC_FALSE;
448   ierr          = PetscMalloc((bi[n]+1)*sizeof(MatScalar)*bs2,&b->a);CHKERRQ(ierr);
449   b->j          = bj;
450   b->i          = bi;
451   b->diag       = bdiag;
452   b->free_diag  = PETSC_TRUE;
453   b->ilen       = 0;
454   b->imax       = 0;
455   b->row        = isrow;
456   b->col        = iscol;
457   b->pivotinblocks = (info->pivotinblocks) ? PETSC_TRUE : PETSC_FALSE;
458   ierr          = PetscObjectReference((PetscObject)isrow);CHKERRQ(ierr);
459   ierr          = PetscObjectReference((PetscObject)iscol);CHKERRQ(ierr);
460   b->icol       = isicol;
461   ierr = PetscMalloc((bs*n+bs)*sizeof(PetscScalar),&b->solve_work);CHKERRQ(ierr);
462   ierr = PetscLogObjectMemory(B,(bi[n]-n)*(sizeof(PetscInt)+sizeof(PetscScalar)*bs2));CHKERRQ(ierr);
463 
464   b->maxnz = b->nz = bi[n] ;
465   (B)->factortype            =  MAT_FACTOR_LU;
466   (B)->info.factor_mallocs   = reallocs;
467   (B)->info.fill_ratio_given = f;
468 
469   if (ai[n] != 0) {
470     (B)->info.fill_ratio_needed = ((PetscReal)bi[n])/((PetscReal)ai[n]);
471   } else {
472     (B)->info.fill_ratio_needed = 0.0;
473   }
474 
475   ierr = ISIdentity(isrow,&row_identity);CHKERRQ(ierr);
476   ierr = ISIdentity(iscol,&col_identity);CHKERRQ(ierr);
477   both_identity = (PetscTruth) (row_identity && col_identity);
478   ierr = MatSeqBAIJSetNumericFactorization_inplace(B,both_identity);CHKERRQ(ierr);
479   PetscFunctionReturn(0);
480  }
481 
482