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:   case MAT_SYMMETRIC:
116:   case MAT_STRUCTURALLY_SYMMETRIC:
117:   case MAT_NOT_SYMMETRIC:
118:   case MAT_NOT_STRUCTURALLY_SYMMETRIC:
119:   case MAT_HERMITIAN:
120:   case MAT_NOT_HERMITIAN:
121:   case MAT_SYMMETRY_ETERNAL:
122:   case MAT_NOT_SYMMETRY_ETERNAL:
123:     PetscInfo1(A,"Option %s ignored\n",MatOptions[op]);
124:     break;
125:   default:
126:     SETERRQ1(PETSC_ERR_SUP,"unknown option %d",op);
127:   }
128:   return(0);
129: }

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

378: PetscErrorCode MatSetUpPreallocation_SeqBDiag(Mat A)
379: {

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

387: /* -------------------------------------------------------------------*/
388: static struct _MatOps MatOps_Values = {MatSetValues_SeqBDiag_N,
389:        MatGetRow_SeqBDiag,
390:        MatRestoreRow_SeqBDiag,
391:        MatMult_SeqBDiag_N,
392: /* 4*/ MatMultAdd_SeqBDiag_N,
393:        MatMultTranspose_SeqBDiag_N,
394:        MatMultTransposeAdd_SeqBDiag_N,
395:        MatSolve_SeqBDiag_N,
396:        0,
397:        0,
398: /*10*/ 0,
399:        0,
400:        0,
401:        MatRelax_SeqBDiag_N,
402:        MatTranspose_SeqBDiag,
403: /*15*/ MatGetInfo_SeqBDiag,
404:        0,
405:        MatGetDiagonal_SeqBDiag_N,
406:        MatDiagonalScale_SeqBDiag,
407:        MatNorm_SeqBDiag,
408: /*20*/ 0,
409:        MatAssemblyEnd_SeqBDiag,
410:        0,
411:        MatSetOption_SeqBDiag,
412:        MatZeroEntries_SeqBDiag,
413: /*25*/ MatZeroRows_SeqBDiag,
414:        0,
415:        MatLUFactorNumeric_SeqBDiag_N,
416:        0,
417:        0,
418: /*30*/ MatSetUpPreallocation_SeqBDiag,
419:        MatILUFactorSymbolic_SeqBDiag,
420:        0,
421:        0,
422:        0,
423: /*35*/ MatDuplicate_SeqBDiag,
424:        0,
425:        0,
426:        MatILUFactor_SeqBDiag,
427:        0,
428: /*40*/ 0,
429:        MatGetSubMatrices_SeqBDiag,
430:        0,
431:        MatGetValues_SeqBDiag_N,
432:        0,
433: /*45*/ 0,
434:        MatScale_SeqBDiag,
435:        0,
436:        0,
437:        0,
438: /*50*/ 0,
439:        0,
440:        0,
441:        0,
442:        0,
443: /*55*/ 0,
444:        0,
445:        0,
446:        0,
447:        0,
448: /*60*/ 0,
449:        MatDestroy_SeqBDiag,
450:        MatView_SeqBDiag,
451:        0,
452:        0,
453: /*65*/ 0,
454:        0,
455:        0,
456:        0,
457:        0,
458: /*70*/ 0,
459:        0,
460:        0,
461:        0,
462:        0,
463: /*75*/ 0,
464:        0,
465:        0,
466:        0,
467:        0,
468: /*80*/ 0,
469:        0,
470:        0,
471:        0,
472:        MatLoad_SeqBDiag,
473: /*85*/ 0,
474:        0,
475:        0,
476:        0,
477:        0,
478: /*90*/ 0,
479:        0,
480:        0,
481:        0,
482:        0,
483: /*95*/ 0,
484:        0,
485:        0,
486:        0};

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

493:    Collective on MPI_Comm

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

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

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

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

519:    Level: intermediate

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

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

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

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


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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

728:   /* 
729:      This code adds extra rows to make sure the number of rows is 
730:     divisible by the blocksize
731:   */
732:   bs = 1;
733:   PetscOptionsGetInt(PETSC_NULL,"-matload_block_size",&bs,PETSC_NULL);
734:   extra_rows = bs - M + bs*(M/bs);
735:   if (extra_rows == bs) extra_rows = 0;
736:   if (extra_rows) {
737:     PetscInfo(0,"Padding loaded matrix to match blocksize\n");
738:   }

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

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

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

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

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

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

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

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

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

791:   Level: beginner

793: .seealso: MatCreateSeqBDiag
794: M*/

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

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


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

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

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

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

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

835:    Collective on MPI_Comm

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

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

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

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

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

866:    Level: intermediate

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

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

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