Actual source code: bdiag.c

  1: #define PETSCMAT_DLL

  3: /* Block diagonal matrix format */

 5:  #include src/mat/impls/bdiag/seq/bdiag.h
 6:  #include src/inline/ilu.h

 10: PetscErrorCode MatDestroy_SeqBDiag(Mat A)
 11: {
 12:   Mat_SeqBDiag   *a = (Mat_SeqBDiag*)A->data;
 14:   PetscInt       i,bs = A->rmap.bs;

 17: #if defined(PETSC_USE_LOG)
 18:   PetscLogObjectState((PetscObject)A,"Rows=%D, Cols=%D, NZ=%D, BSize=%D, NDiag=%D",A->rmap.N,A->cmap.n,a->nz,A->rmap.bs,a->nd);
 19: #endif
 20:   if (!a->user_alloc) { /* Free the actual diagonals */
 21:     for (i=0; i<a->nd; i++) {
 22:       if (a->diag[i] > 0) {
 23:         PetscScalar *dummy = a->diagv[i] + bs*bs*a->diag[i];
 24:         PetscFree(dummy);
 25:       } else {
 26:         PetscFree(a->diagv[i]);
 27:       }
 28:     }
 29:   }
 30:   PetscFree(a->pivot);
 31:   PetscFree(a->diagv);
 32:   PetscFree(a->diag);
 33:   PetscFree(a->colloc);
 34:   PetscFree(a->dvalue);
 35:   PetscFree(a->solvework);
 36:   PetscFree(a);

 38:   PetscObjectChangeTypeName((PetscObject)A,0);
 39:   PetscObjectComposeFunction((PetscObject)A,"MatSeqBDiagSetPreallocation_C","",PETSC_NULL);
 40:   return(0);
 41: }

 45: PetscErrorCode MatAssemblyEnd_SeqBDiag(Mat A,MatAssemblyType mode)
 46: {
 47:   Mat_SeqBDiag   *a = (Mat_SeqBDiag*)A->data;
 48:   PetscInt       i,k,temp,*diag = a->diag,*bdlen = a->bdlen;
 49:   PetscScalar    *dtemp,**dv = a->diagv;

 53:   if (mode == MAT_FLUSH_ASSEMBLY) return(0);

 55:   /* Sort diagonals */
 56:   for (i=0; i<a->nd; i++) {
 57:     for (k=i+1; k<a->nd; k++) {
 58:       if (diag[i] < diag[k]) {
 59:         temp     = diag[i];
 60:         diag[i]  = diag[k];
 61:         diag[k]  = temp;
 62:         temp     = bdlen[i];
 63:         bdlen[i] = bdlen[k];
 64:         bdlen[k] = temp;
 65:         dtemp    = dv[i];
 66:         dv[i]    = dv[k];
 67:         dv[k]    = dtemp;
 68:       }
 69:     }
 70:   }

 72:   /* Set location of main diagonal */
 73:   for (i=0; i<a->nd; i++) {
 74:     if (!a->diag[i]) {a->mainbd = i; break;}
 75:   }
 76:   PetscInfo3(A,"Number diagonals %D,memory used %D, block size %D\n",a->nd,a->maxnz,A->rmap.bs);
 77:   return(0);
 78: }

 82: PetscErrorCode MatSetOption_SeqBDiag(Mat A,MatOption op)
 83: {
 84:   Mat_SeqBDiag   *a = (Mat_SeqBDiag*)A->data;

 88:   switch (op) {
 89:   case MAT_NO_NEW_NONZERO_LOCATIONS:
 90:     a->nonew       = 1;
 91:     break;
 92:   case MAT_YES_NEW_NONZERO_LOCATIONS:
 93:     a->nonew       = 0;
 94:     break;
 95:   case MAT_NO_NEW_DIAGONALS:
 96:     a->nonew_diag  = 1;
 97:     break;
 98:   case MAT_YES_NEW_DIAGONALS:
 99:     a->nonew_diag  = 0;
100:     break;
101:   case MAT_COLUMN_ORIENTED:
102:     a->roworiented = PETSC_FALSE;
103:     break;
104:   case MAT_ROW_ORIENTED:
105:     a->roworiented = PETSC_TRUE;
106:     break;
107:   case MAT_ROWS_SORTED:
108:   case MAT_ROWS_UNSORTED:
109:   case MAT_COLUMNS_SORTED:
110:   case MAT_COLUMNS_UNSORTED:
111:   case MAT_IGNORE_OFF_PROC_ENTRIES:
112:   case MAT_NEW_NONZERO_LOCATION_ERR:
113:   case MAT_NEW_NONZERO_ALLOCATION_ERR:
114:   case MAT_USE_HASH_TABLE:
115:     PetscInfo1(A,"Option %d ignored\n",op);
116:     break;
117:   case MAT_SYMMETRIC:
118:   case MAT_STRUCTURALLY_SYMMETRIC:
119:   case MAT_NOT_SYMMETRIC:
120:   case MAT_NOT_STRUCTURALLY_SYMMETRIC:
121:   case MAT_HERMITIAN:
122:   case MAT_NOT_HERMITIAN:
123:   case MAT_SYMMETRY_ETERNAL:
124:   case MAT_NOT_SYMMETRY_ETERNAL:
125:     break;
126:   default:
127:     SETERRQ1(PETSC_ERR_SUP,"unknown option %d",op);
128:   }
129:   return(0);
130: }

134: static PetscErrorCode MatGetDiagonal_SeqBDiag_N(Mat A,Vec v)
135: {
136:   Mat_SeqBDiag   *a = (Mat_SeqBDiag*)A->data;
138:   PetscInt       i,j,n,len,ibase,bs = A->rmap.bs,iloc;
139:   PetscScalar    *x,*dd,zero = 0.0;

142:   if (A->factor) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Not for factored matrix");
143:   VecSet(v,zero);
144:   VecGetLocalSize(v,&n);
145:   if (n != A->rmap.N) SETERRQ(PETSC_ERR_ARG_SIZ,"Nonconforming mat and vec");
146:   if (a->mainbd == -1) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Main diagonal not set");
147:   len = PetscMin(a->mblock,a->nblock);
148:   dd = a->diagv[a->mainbd];
149:   VecGetArray(v,&x);
150:   for (i=0; i<len; i++) {
151:     ibase = i*bs*bs;  iloc = i*bs;
152:     for (j=0; j<bs; j++) x[j + iloc] = dd[ibase + j*(bs+1)];
153:   }
154:   VecRestoreArray(v,&x);
155:   return(0);
156: }

160: static PetscErrorCode MatGetDiagonal_SeqBDiag_1(Mat A,Vec v)
161: {
162:   Mat_SeqBDiag   *a = (Mat_SeqBDiag*)A->data;
164:   PetscInt       i,n,len;
165:   PetscScalar    *x,*dd,zero = 0.0;

168:   VecSet(v,zero);
169:   VecGetLocalSize(v,&n);
170:   if (n != A->rmap.N) SETERRQ(PETSC_ERR_ARG_SIZ,"Nonconforming mat and vec");
171:   if (a->mainbd == -1) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Main diagonal not set");
172:   dd = a->diagv[a->mainbd];
173:   len = PetscMin(A->rmap.n,A->cmap.n);
174:   VecGetArray(v,&x);
175:   for (i=0; i<len; i++) x[i] = dd[i];
176:   VecRestoreArray(v,&x);
177:   return(0);
178: }

182: PetscErrorCode MatZeroEntries_SeqBDiag(Mat A)
183: {
184:   Mat_SeqBDiag *a = (Mat_SeqBDiag*)A->data;
185:   PetscInt     d,i,len,bs = A->rmap.bs;
186:   PetscScalar  *dv;

189:   for (d=0; d<a->nd; d++) {
190:     dv  = a->diagv[d];
191:     if (a->diag[d] > 0) {
192:       dv += bs*bs*a->diag[d];
193:     }
194:     len = a->bdlen[d]*bs*bs;
195:     for (i=0; i<len; i++) dv[i] = 0.0;
196:   }
197:   return(0);
198: }

202: PetscErrorCode MatZeroRows_SeqBDiag(Mat A,PetscInt N,const PetscInt rows[],PetscScalar diag)
203: {
204:   Mat_SeqBDiag   *a = (Mat_SeqBDiag*)A->data;
206:   PetscInt       i,m = A->rmap.N - 1,nz;
207:   PetscScalar    *dd;
208:   PetscScalar    *val;

211:   for (i=0; i<N; i++) {
212:     if (rows[i]<0 || rows[i]>m) SETERRQ(PETSC_ERR_ARG_OUTOFRANGE,"row out of range");
213:     MatGetRow_SeqBDiag(A,rows[i],&nz,PETSC_NULL,&val);
214:     PetscMemzero((void*)val,nz*sizeof(PetscScalar));
215:     MatRestoreRow_SeqBDiag(A,rows[i],&nz,PETSC_NULL,&val);
216:   }
217:   if (diag != 0.0) {
218:     if (a->mainbd == -1) SETERRQ(PETSC_ERR_ARG_WRONGSTATE,"Main diagonal does not exist");
219:     dd = a->diagv[a->mainbd];
220:     for (i=0; i<N; i++) dd[rows[i]] = diag;
221:   }
222:   MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);
223:   MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);
224:   return(0);
225: }

229: PetscErrorCode MatGetSubMatrix_SeqBDiag(Mat A,IS isrow,IS iscol,MatReuse scall,Mat *submat)
230: {
232:   PetscInt       nznew,*smap,i,j,oldcols = A->cmap.n;
233:   PetscInt       *irow,*icol,newr,newc,*cwork,nz,bs;
234:   PetscInt       *col;
235:   PetscScalar    *vwork;
236:   PetscScalar    *val;
237:   Mat            newmat;

240:   if (scall == MAT_REUSE_MATRIX) { /* no support for reuse so simply destroy all */
241:     MatDestroy(*submat);
242:   }

244:   ISGetIndices(isrow,&irow);
245:   ISGetIndices(iscol,&icol);
246:   ISGetLocalSize(isrow,&newr);
247:   ISGetLocalSize(iscol,&newc);

249:   PetscMalloc((oldcols+1)*sizeof(PetscInt),&smap);
250:   PetscMalloc((newc+1)*sizeof(PetscInt),&cwork);
251:   PetscMalloc((newc+1)*sizeof(PetscScalar),&vwork);
252:   PetscMemzero((char*)smap,oldcols*sizeof(PetscInt));
253:   for (i=0; i<newc; i++) smap[icol[i]] = i+1;

255:   /* Determine diagonals; then create submatrix */
256:   bs = A->rmap.bs; /* Default block size remains the same */
257:   MatCreate(A->comm,&newmat);
258:   MatSetSizes(newmat,newr,newc,newr,newc);
259:   MatSetType(newmat,A->type_name);
260:   MatSeqBDiagSetPreallocation(newmat,0,bs,PETSC_NULL,PETSC_NULL);

262:   /* Fill new matrix */
263:   for (i=0; i<newr; i++) {
264:     MatGetRow_SeqBDiag(A,irow[i],&nz,&col,&val);
265:     nznew = 0;
266:     for (j=0; j<nz; j++) {
267:       if (smap[col[j]]) {
268:         cwork[nznew]   = smap[col[j]] - 1;
269:         vwork[nznew++] = val[j];
270:       }
271:     }
272:     MatSetValues(newmat,1,&i,nznew,cwork,vwork,INSERT_VALUES);
273:     MatRestoreRow_SeqBDiag(A,i,&nz,&col,&val);
274:   }
275:   MatAssemblyBegin(newmat,MAT_FINAL_ASSEMBLY);
276:   MatAssemblyEnd(newmat,MAT_FINAL_ASSEMBLY);

278:   /* Free work space */
279:   PetscFree(smap);
280:   PetscFree(cwork);
281:   PetscFree(vwork);
282:   ISRestoreIndices(isrow,&irow);
283:   ISRestoreIndices(iscol,&icol);
284:   *submat = newmat;
285:   return(0);
286: }

290: PetscErrorCode MatGetSubMatrices_SeqBDiag(Mat A,PetscInt n,const IS irow[],const IS icol[],MatReuse scall,Mat *B[])
291: {
293:   PetscInt       i;

296:   if (scall == MAT_INITIAL_MATRIX) {
297:     PetscMalloc((n+1)*sizeof(Mat),B);
298:   }

300:   for (i=0; i<n; i++) {
301:     MatGetSubMatrix_SeqBDiag(A,irow[i],icol[i],scall,&(*B)[i]);
302:   }
303:   return(0);
304: }

308: PetscErrorCode MatScale_SeqBDiag(Mat inA,PetscScalar alpha)
309: {
310:   Mat_SeqBDiag *a = (Mat_SeqBDiag*)inA->data;
311:   PetscInt          i,bs = inA->rmap.bs;
312:   PetscScalar  oalpha = alpha;
313:   PetscBLASInt one = 1,len;

317:   for (i=0; i<a->nd; i++) {
318:     len = (PetscBLASInt)bs*bs*a->bdlen[i];
319:     if (a->diag[i] > 0) {
320:       BLASscal_(&len,&oalpha,a->diagv[i] + bs*bs*a->diag[i],&one);
321:     } else {
322:       BLASscal_(&len,&oalpha,a->diagv[i],&one);
323:     }
324:   }
325:   PetscLogFlops(a->nz);
326:   return(0);
327: }

331: PetscErrorCode MatDiagonalScale_SeqBDiag(Mat A,Vec ll,Vec rr)
332: {
333:   Mat_SeqBDiag   *a = (Mat_SeqBDiag*)A->data;
334:   PetscScalar    *l,*r,*dv;
336:   PetscInt       d,j,len;
337:   PetscInt       nd = a->nd,bs = A->rmap.bs,diag,m,n;

340:   if (ll) {
341:     VecGetSize(ll,&m);
342:     if (m != A->rmap.N) SETERRQ(PETSC_ERR_ARG_SIZ,"Left scaling vector wrong length");
343:     if (bs == 1) {
344:       VecGetArray(ll,&l);
345:       for (d=0; d<nd; d++) {
346:         dv   = a->diagv[d];
347:         diag = a->diag[d];
348:         len  = a->bdlen[d];
349:         if (diag > 0) for (j=0; j<len; j++) dv[j+diag] *= l[j+diag];
350:         else          for (j=0; j<len; j++) dv[j]      *= l[j];
351:       }
352:       VecRestoreArray(ll,&l);
353:       PetscLogFlops(a->nz);
354:     } else SETERRQ(PETSC_ERR_SUP,"Not yet done for bs>1");
355:   }
356:   if (rr) {
357:     VecGetSize(rr,&n);
358:     if (n != A->cmap.n) SETERRQ(PETSC_ERR_ARG_SIZ,"Right scaling vector wrong length");
359:     if (bs == 1) {
360:       VecGetArray(rr,&r);
361:       for (d=0; d<nd; d++) {
362:         dv   = a->diagv[d];
363:         diag = a->diag[d];
364:         len  = a->bdlen[d];
365:         if (diag > 0) for (j=0; j<len; j++) dv[j+diag] *= r[j];
366:         else          for (j=0; j<len; j++) dv[j]      *= r[j-diag];
367:       }
368:       VecRestoreArray(rr,&r);
369:       PetscLogFlops(a->nz);
370:     } else SETERRQ(PETSC_ERR_SUP,"Not yet done for bs>1");
371:   }
372:   return(0);
373: }

375: static PetscErrorCode MatDuplicate_SeqBDiag(Mat,MatDuplicateOption,Mat *);

379: PetscErrorCode MatSetUpPreallocation_SeqBDiag(Mat A)
380: {

384:    MatSeqBDiagSetPreallocation(A,PETSC_DEFAULT,PETSC_DEFAULT,0,0);
385:   return(0);
386: }

388: /* -------------------------------------------------------------------*/
389: static struct _MatOps MatOps_Values = {MatSetValues_SeqBDiag_N,
390:        MatGetRow_SeqBDiag,
391:        MatRestoreRow_SeqBDiag,
392:        MatMult_SeqBDiag_N,
393: /* 4*/ MatMultAdd_SeqBDiag_N,
394:        MatMultTranspose_SeqBDiag_N,
395:        MatMultTransposeAdd_SeqBDiag_N,
396:        MatSolve_SeqBDiag_N,
397:        0,
398:        0,
399: /*10*/ 0,
400:        0,
401:        0,
402:        MatRelax_SeqBDiag_N,
403:        MatTranspose_SeqBDiag,
404: /*15*/ MatGetInfo_SeqBDiag,
405:        0,
406:        MatGetDiagonal_SeqBDiag_N,
407:        MatDiagonalScale_SeqBDiag,
408:        MatNorm_SeqBDiag,
409: /*20*/ 0,
410:        MatAssemblyEnd_SeqBDiag,
411:        0,
412:        MatSetOption_SeqBDiag,
413:        MatZeroEntries_SeqBDiag,
414: /*25*/ MatZeroRows_SeqBDiag,
415:        0,
416:        MatLUFactorNumeric_SeqBDiag_N,
417:        0,
418:        0,
419: /*30*/ MatSetUpPreallocation_SeqBDiag,
420:        MatILUFactorSymbolic_SeqBDiag,
421:        0,
422:        0,
423:        0,
424: /*35*/ MatDuplicate_SeqBDiag,
425:        0,
426:        0,
427:        MatILUFactor_SeqBDiag,
428:        0,
429: /*40*/ 0,
430:        MatGetSubMatrices_SeqBDiag,
431:        0,
432:        MatGetValues_SeqBDiag_N,
433:        0,
434: /*45*/ 0,
435:        MatScale_SeqBDiag,
436:        0,
437:        0,
438:        0,
439: /*50*/ 0,
440:        0,
441:        0,
442:        0,
443:        0,
444: /*55*/ 0,
445:        0,
446:        0,
447:        0,
448:        0,
449: /*60*/ 0,
450:        MatDestroy_SeqBDiag,
451:        MatView_SeqBDiag,
452:        0,
453:        0,
454: /*65*/ 0,
455:        0,
456:        0,
457:        0,
458:        0,
459: /*70*/ 0,
460:        0,
461:        0,
462:        0,
463:        0,
464: /*75*/ 0,
465:        0,
466:        0,
467:        0,
468:        0,
469: /*80*/ 0,
470:        0,
471:        0,
472:        0,
473:        MatLoad_SeqBDiag,
474: /*85*/ 0,
475:        0,
476:        0,
477:        0,
478:        0,
479: /*90*/ 0,
480:        0,
481:        0,
482:        0,
483:        0,
484: /*95*/ 0,
485:        0,
486:        0,
487:        0};

491: /*@C
492:    MatSeqBDiagSetPreallocation - Sets the nonzero structure and (optionally) arrays.

494:    Collective on MPI_Comm

496:    Input Parameters:
497: +  B - the matrix
498: .  nd - number of block diagonals (optional)
499: .  bs - each element of a diagonal is an bs x bs dense matrix
500: .  diag - optional array of block diagonal numbers (length nd).
501:    For a matrix element A[i,j], where i=row and j=column, the
502:    diagonal number is
503: $     diag = i/bs - j/bs  (integer division)
504:    Set diag=PETSC_NULL on input for PETSc to dynamically allocate memory as 
505:    needed (expensive).
506: -  diagv - pointer to actual diagonals (in same order as diag array), 
507:    if allocated by user.  Otherwise, set diagv=PETSC_NULL on input for PETSc
508:    to control memory allocation.

510:    Options Database Keys:
511: .  -mat_block_size <bs> - Sets blocksize
512: .  -mat_bdiag_diags <s1,s2,s3,...> - Sets diagonal numbers

514:    Notes:
515:    See the users manual for further details regarding this storage format.

517:    Fortran Note:
518:    Fortran programmers cannot set diagv; this value is ignored.

520:    Level: intermediate

522: .keywords: matrix, block, diagonal, sparse

524: .seealso: MatCreate(), MatCreateMPIBDiag(), MatSetValues()
525: @*/
526: PetscErrorCode  MatSeqBDiagSetPreallocation(Mat B,PetscInt nd,PetscInt bs,const PetscInt diag[],PetscScalar *diagv[])
527: {
528:   PetscErrorCode ierr,(*f)(Mat,PetscInt,PetscInt,const PetscInt[],PetscScalar*[]);

531:   PetscObjectQueryFunction((PetscObject)B,"MatSeqBDiagSetPreallocation_C",(void (**)(void))&f);
532:   if (f) {
533:     (*f)(B,nd,bs,diag,diagv);
534:   }
535:   return(0);
536: }

541: PetscErrorCode  MatSeqBDiagSetPreallocation_SeqBDiag(Mat B,PetscInt nd,PetscInt bs,PetscInt *diag,PetscScalar **diagv)
542: {
543:   Mat_SeqBDiag   *b;
545:   PetscInt       i,nda,sizetot, nd2 = 128,idiag[128];
546:   PetscTruth     flg1;


550:   B->preallocated = PETSC_TRUE;
551:   if (bs == PETSC_DEFAULT) bs = 1;
552:   if (!bs) SETERRQ(PETSC_ERR_ARG_OUTOFRANGE,"Blocksize cannot be zero");
553:   if (nd == PETSC_DEFAULT) nd = 0;
554:   PetscOptionsGetInt(PETSC_NULL,"-mat_block_size",&bs,PETSC_NULL);
555:   PetscOptionsGetIntArray(PETSC_NULL,"-mat_bdiag_diags",idiag,&nd2,&flg1);
556:   if (flg1) {
557:     diag = idiag;
558:     nd   = nd2;
559:   }

561:   B->rmap.bs = B->cmap.bs = bs;
562:   PetscMapInitialize(B->comm,&B->rmap);
563:   PetscMapInitialize(B->comm,&B->cmap);

565:   if ((B->cmap.n%bs) || (B->rmap.N%bs)) SETERRQ(PETSC_ERR_ARG_SIZ,"Invalid block size");
566:   if (!nd) nda = nd + 1;
567:   else     nda = nd;
568:   b            = (Mat_SeqBDiag*)B->data;

570:   PetscOptionsHasName(PETSC_NULL,"-mat_no_unroll",&flg1);
571:   if (!flg1) {
572:     switch (bs) {
573:       case 1:
574:         B->ops->setvalues       = MatSetValues_SeqBDiag_1;
575:         B->ops->getvalues       = MatGetValues_SeqBDiag_1;
576:         B->ops->getdiagonal     = MatGetDiagonal_SeqBDiag_1;
577:         B->ops->mult            = MatMult_SeqBDiag_1;
578:         B->ops->multadd         = MatMultAdd_SeqBDiag_1;
579:         B->ops->multtranspose   = MatMultTranspose_SeqBDiag_1;
580:         B->ops->multtransposeadd= MatMultTransposeAdd_SeqBDiag_1;
581:         B->ops->relax           = MatRelax_SeqBDiag_1;
582:         B->ops->solve           = MatSolve_SeqBDiag_1;
583:         B->ops->lufactornumeric = MatLUFactorNumeric_SeqBDiag_1;
584:         break;
585:       case 2:
586:         B->ops->mult            = MatMult_SeqBDiag_2;
587:         B->ops->multadd         = MatMultAdd_SeqBDiag_2;
588:         B->ops->solve           = MatSolve_SeqBDiag_2;
589:         break;
590:       case 3:
591:         B->ops->mult            = MatMult_SeqBDiag_3;
592:         B->ops->multadd         = MatMultAdd_SeqBDiag_3;
593:         B->ops->solve           = MatSolve_SeqBDiag_3;
594:         break;
595:       case 4:
596:         B->ops->mult            = MatMult_SeqBDiag_4;
597:         B->ops->multadd         = MatMultAdd_SeqBDiag_4;
598:         B->ops->solve           = MatSolve_SeqBDiag_4;
599:         break;
600:       case 5:
601:         B->ops->mult            = MatMult_SeqBDiag_5;
602:         B->ops->multadd         = MatMultAdd_SeqBDiag_5;
603:         B->ops->solve           = MatSolve_SeqBDiag_5;
604:         break;
605:    }
606:   }

608:   b->mblock = B->rmap.N/bs;
609:   b->nblock = B->cmap.n/bs;
610:   b->nd     = nd;
611:   B->rmap.bs     = bs;
612:   b->ndim   = 0;
613:   b->mainbd = -1;
614:   b->pivot  = 0;

616:   PetscMalloc(2*nda*sizeof(PetscInt),&b->diag);
617:   b->bdlen  = b->diag + nda;
618:   PetscMalloc((B->cmap.n+1)*sizeof(PetscInt),&b->colloc);
619:   PetscMalloc(nda*sizeof(PetscScalar*),&b->diagv);
620:   sizetot   = 0;

622:   if (diagv) { /* user allocated space */
623:     b->user_alloc = PETSC_TRUE;
624:     for (i=0; i<nd; i++) b->diagv[i] = diagv[i];
625:   } else b->user_alloc = PETSC_FALSE;

627:   for (i=0; i<nd; i++) {
628:     b->diag[i] = diag[i];
629:     if (diag[i] > 0) { /* lower triangular */
630:       b->bdlen[i] = PetscMin(b->nblock,b->mblock - diag[i]);
631:     } else {           /* upper triangular */
632:       b->bdlen[i] = PetscMin(b->mblock,b->nblock + diag[i]);
633:     }
634:     sizetot += b->bdlen[i];
635:   }
636:   sizetot   *= bs*bs;
637:   b->maxnz  =  sizetot;
638:   PetscMalloc((B->cmap.n+1)*sizeof(PetscScalar),&b->dvalue);
639:   PetscLogObjectMemory(B,(nda*(bs+2))*sizeof(PetscInt) + bs*nda*sizeof(PetscScalar)
640:                     + nda*sizeof(PetscScalar*) + sizeof(Mat_SeqBDiag)
641:                     + sizeof(struct _p_Mat) + sizetot*sizeof(PetscScalar));

643:   if (!b->user_alloc) {
644:     for (i=0; i<nd; i++) {
645:       PetscMalloc(bs*bs*b->bdlen[i]*sizeof(PetscScalar),&b->diagv[i]);
646:       PetscMemzero(b->diagv[i],bs*bs*b->bdlen[i]*sizeof(PetscScalar));
647:     }
648:     b->nonew = 0; b->nonew_diag = 0;
649:   } else { /* diagonals are set on input; don't allow dynamic allocation */
650:     b->nonew = 1; b->nonew_diag = 1;
651:   }

653:   /* adjust diagv so one may access rows with diagv[diag][row] for all rows */
654:   for (i=0; i<nd; i++) {
655:     if (diag[i] > 0) {
656:       b->diagv[i] -= bs*bs*diag[i];
657:     }
658:   }

660:   b->nz          = b->maxnz; /* Currently not keeping track of exact count */
661:   b->roworiented = PETSC_TRUE;
662:   B->info.nz_unneeded = (double)b->maxnz;
663:   return(0);
664: }

669: static PetscErrorCode MatDuplicate_SeqBDiag(Mat A,MatDuplicateOption cpvalues,Mat *matout)
670: {
671:   Mat_SeqBDiag   *newmat,*a = (Mat_SeqBDiag*)A->data;
673:   PetscInt       i,len,diag,bs = A->rmap.bs;
674:   Mat            mat;

677:   MatCreate(A->comm,matout);
678:   MatSetSizes(*matout,A->rmap.N,A->cmap.n,A->rmap.N,A->cmap.n);
679:   MatSetType(*matout,A->type_name);
680:   MatSeqBDiagSetPreallocation(*matout,a->nd,bs,a->diag,PETSC_NULL);

682:   /* Copy contents of diagonals */
683:   mat = *matout;
684:   newmat = (Mat_SeqBDiag*)mat->data;
685:   if (cpvalues == MAT_COPY_VALUES) {
686:     for (i=0; i<a->nd; i++) {
687:       len = a->bdlen[i] * bs * bs * sizeof(PetscScalar);
688:       diag = a->diag[i];
689:       if (diag > 0) {
690:         PetscMemcpy(newmat->diagv[i]+bs*bs*diag,a->diagv[i]+bs*bs*diag,len);
691:       } else {
692:         PetscMemcpy(newmat->diagv[i],a->diagv[i],len);
693:       }
694:     }
695:   }
696:   MatAssemblyBegin(mat,MAT_FINAL_ASSEMBLY);
697:   MatAssemblyEnd(mat,MAT_FINAL_ASSEMBLY);
698:   return(0);
699: }

703: PetscErrorCode MatLoad_SeqBDiag(PetscViewer viewer, MatType type,Mat *A)
704: {
705:   Mat            B;
707:   PetscMPIInt    size;
708:   int            fd;
709:   PetscInt       *scols,i,nz,header[4],nd = 128;
710:   PetscInt       bs,*rowlengths = 0,M,N,*cols,extra_rows,*diag = 0;
711:   PetscInt       idiag[128];
712:   PetscScalar    *vals,*svals;
713:   MPI_Comm       comm;
714:   PetscTruth     flg;
715: 
717:   PetscObjectGetComm((PetscObject)viewer,&comm);
718:   MPI_Comm_size(comm,&size);
719:   if (size > 1) SETERRQ(PETSC_ERR_ARG_SIZ,"view must have one processor");
720:   PetscViewerBinaryGetDescriptor(viewer,&fd);
721:   PetscBinaryRead(fd,header,4,PETSC_INT);
722:   if (header[0] != MAT_FILE_COOKIE) SETERRQ(PETSC_ERR_FILE_UNEXPECTED,"Not matrix object");
723:   M = header[1]; N = header[2]; nz = header[3];
724:   if (M != N) SETERRQ(PETSC_ERR_SUP,"Can only load square matrices");
725:   if (header[3] < 0) {
726:     SETERRQ(PETSC_ERR_FILE_UNEXPECTED,"Matrix stored in special format, cannot load as SeqBDiag");
727:   }

729:   /* 
730:      This code adds extra rows to make sure the number of rows is 
731:     divisible by the blocksize
732:   */
733:   bs = 1;
734:   PetscOptionsGetInt(PETSC_NULL,"-matload_block_size",&bs,PETSC_NULL);
735:   extra_rows = bs - M + bs*(M/bs);
736:   if (extra_rows == bs) extra_rows = 0;
737:   if (extra_rows) {
738:     PetscInfo(0,"Padding loaded matrix to match blocksize\n");
739:   }

741:   /* read row lengths */
742:   PetscMalloc((M+extra_rows)*sizeof(PetscInt),&rowlengths);
743:   PetscBinaryRead(fd,rowlengths,M,PETSC_INT);
744:   for (i=0; i<extra_rows; i++) rowlengths[M+i] = 1;

746:   /* load information about diagonals */
747:   PetscOptionsGetIntArray(PETSC_NULL,"-matload_bdiag_diags",idiag,&nd,&flg);
748:   if (flg) {
749:     diag = idiag;
750:   }

752:   /* create our matrix */
753:   MatCreate(comm,A);
754:   MatSetSizes(*A,M+extra_rows,M+extra_rows,M+extra_rows,M+extra_rows);
755:   MatSetType(*A,type);
756:   MatSeqBDiagSetPreallocation(*A,nd,bs,diag,PETSC_NULL);
757:   B = *A;

759:   /* read column indices and nonzeros */
760:   PetscMalloc(nz*sizeof(PetscInt),&scols);
761:   cols = scols;
762:   PetscBinaryRead(fd,cols,nz,PETSC_INT);
763:   PetscMalloc(nz*sizeof(PetscScalar),&svals);
764:   vals = svals;
765:   PetscBinaryRead(fd,vals,nz,PETSC_SCALAR);
766:   /* insert into matrix */

768:   for (i=0; i<M; i++) {
769:     MatSetValues(B,1,&i,rowlengths[i],scols,svals,INSERT_VALUES);
770:     scols += rowlengths[i]; svals += rowlengths[i];
771:   }
772:   vals[0] = 1.0;
773:   for (i=M; i<M+extra_rows; i++) {
774:     MatSetValues(B,1,&i,1,&i,vals,INSERT_VALUES);
775:   }

777:   PetscFree(cols);
778:   PetscFree(vals);
779:   PetscFree(rowlengths);

781:   MatAssemblyBegin(B,MAT_FINAL_ASSEMBLY);
782:   MatAssemblyEnd(B,MAT_FINAL_ASSEMBLY);
783:   return(0);
784: }

786: /*MC
787:    MATSEQBDIAG - MATSEQBDIAG = "seqbdiag" - A matrix type to be used for sequential block diagonal matrices.

789:    Options Database Keys:
790: . -mat_type seqbdiag - sets the matrix type to "seqbdiag" during a call to MatSetFromOptions()

792:   Level: beginner

794: .seealso: MatCreateSeqBDiag
795: M*/

800: PetscErrorCode  MatCreate_SeqBDiag(Mat B)
801: {
802:   Mat_SeqBDiag   *b;
804:   PetscMPIInt    size;

807:   MPI_Comm_size(B->comm,&size);
808:   if (size > 1) SETERRQ(PETSC_ERR_ARG_WRONG,"Comm must be of size 1");


811:   PetscNew(Mat_SeqBDiag,&b);
812:   B->data         = (void*)b;
813:   PetscMemcpy(B->ops,&MatOps_Values,sizeof(struct _MatOps));
814:   B->factor       = 0;
815:   B->mapping      = 0;

817:   b->ndim   = 0;
818:   b->mainbd = -1;
819:   b->pivot  = 0;

821:   b->roworiented = PETSC_TRUE;
822:   PetscObjectComposeFunctionDynamic((PetscObject)B,"MatSeqBDiagSetPreallocation_C",
823:                                     "MatSeqBDiagSetPreallocation_SeqBDiag",
824:                                      MatSeqBDiagSetPreallocation_SeqBDiag);

826:   PetscObjectChangeTypeName((PetscObject)B,MATSEQBDIAG);
827:   return(0);
828: }

833: /*@C
834:    MatCreateSeqBDiag - Creates a sequential block diagonal matrix.

836:    Collective on MPI_Comm

838:    Input Parameters:
839: +  comm - MPI communicator, set to PETSC_COMM_SELF
840: .  m - number of rows
841: .  n - number of columns
842: .  nd - number of block diagonals (optional)
843: .  bs - each element of a diagonal is an bs x bs dense matrix
844: .  diag - optional array of block diagonal numbers (length nd).
845:    For a matrix element A[i,j], where i=row and j=column, the
846:    diagonal number is
847: $     diag = i/bs - j/bs  (integer division)
848:    Set diag=PETSC_NULL on input for PETSc to dynamically allocate memory as 
849:    needed (expensive).
850: -  diagv - pointer to actual diagonals (in same order as diag array), 
851:    if allocated by user.  Otherwise, set diagv=PETSC_NULL on input for PETSc
852:    to control memory allocation.

854:    Output Parameters:
855: .  A - the matrix

857:    Options Database Keys:
858: .  -mat_block_size <bs> - Sets blocksize
859: .  -mat_bdiag_diags <s1,s2,s3,...> - Sets diagonal numbers

861:    Notes:
862:    See the users manual for further details regarding this storage format.

864:    Fortran Note:
865:    Fortran programmers cannot set diagv; this value is ignored.

867:    Level: intermediate

869: .keywords: matrix, block, diagonal, sparse

871: .seealso: MatCreate(), MatCreateMPIBDiag(), MatSetValues()
872: @*/
873: PetscErrorCode  MatCreateSeqBDiag(MPI_Comm comm,PetscInt m,PetscInt n,PetscInt nd,PetscInt bs,const PetscInt diag[],PetscScalar *diagv[],Mat *A)
874: {

878:   MatCreate(comm,A);
879:   MatSetSizes(*A,m,n,m,n);
880:   MatSetType(*A,MATSEQBDIAG);
881:   MatSeqBDiagSetPreallocation(*A,nd,bs,diag,diagv);
882:   return(0);
883: }