Actual source code: mmaij.c

  1: /*$Id: mmaij.c,v 1.59 2001/08/07 03:02:49 balay Exp $*/

  3: /*
  4:    Support for the parallel AIJ matrix vector multiply
  5: */
 6:  #include src/mat/impls/aij/mpi/mpiaij.h
 7:  #include src/vec/vecimpl.h

 11: int MatSetUpMultiply_MPIAIJ(Mat mat)
 12: {
 13:   Mat_MPIAIJ         *aij = (Mat_MPIAIJ*)mat->data;
 14:   Mat_SeqAIJ         *B = (Mat_SeqAIJ*)(aij->B->data);
 15:   int                N = mat->N,i,j,*indices,*aj = B->j,ierr,ec = 0,*garray;
 16:   IS                 from,to;
 17:   Vec                gvec;
 18: #if defined (PETSC_USE_CTABLE)
 19:   PetscTable         gid1_lid1;
 20:   PetscTablePosition tpos;
 21:   int                gid,lid;
 22: #endif


 26: #if defined (PETSC_USE_CTABLE)
 27:   /* use a table - Mark Adams (this has not been tested with "shift") */
 28:   PetscTableCreate(aij->B->m,&gid1_lid1);
 29:   for (i=0; i<aij->B->m; i++) {
 30:     for (j=0; j<B->ilen[i]; j++) {
 31:       int data,gid1 = aj[B->i[i] + j] + 1;
 32:       PetscTableFind(gid1_lid1,gid1,&data);
 33:       if (!data) {
 34:         /* one based table */
 35:         PetscTableAdd(gid1_lid1,gid1,++ec);
 36:       }
 37:     }
 38:   }
 39:   /* form array of columns we need */
 40:   PetscMalloc((ec+1)*sizeof(int),&garray);
 41:   PetscTableGetHeadPosition(gid1_lid1,&tpos);
 42:   while (tpos) {
 43:     PetscTableGetNext(gid1_lid1,&tpos,&gid,&lid);
 44:     gid--;
 45:     lid--;
 46:     garray[lid] = gid;
 47:   }
 48:   PetscSortInt(ec,garray); /* sort, and rebuild */
 49:   PetscTableRemoveAll(gid1_lid1);
 50:   for (i=0; i<ec; i++) {
 51:     PetscTableAdd(gid1_lid1,garray[i]+1,i+1);
 52:   }
 53:   /* compact out the extra columns in B */
 54:   for (i=0; i<aij->B->m; i++) {
 55:     for (j=0; j<B->ilen[i]; j++) {
 56:       int gid1 = aj[B->i[i] + j] + 1;
 57:       PetscTableFind(gid1_lid1,gid1,&lid);
 58:       lid --;
 59:       aj[B->i[i] + j]  = lid;
 60:     }
 61:   }
 62:   aij->B->n = aij->B->N = ec;
 63:   PetscTableDelete(gid1_lid1);
 64:   /* Mark Adams */
 65: #else
 66:   /* For the first stab we make an array as long as the number of columns */
 67:   /* mark those columns that are in aij->B */
 68:   PetscMalloc((N+1)*sizeof(int),&indices);
 69:   PetscMemzero(indices,N*sizeof(int));
 70:   for (i=0; i<aij->B->m; i++) {
 71:     for (j=0; j<B->ilen[i]; j++) {
 72:       if (!indices[aj[B->i[i] + j] ]) ec++;
 73:       indices[aj[B->i[i] + j] ] = 1;
 74:     }
 75:   }

 77:   /* form array of columns we need */
 78:   PetscMalloc((ec+1)*sizeof(int),&garray);
 79:   ec = 0;
 80:   for (i=0; i<N; i++) {
 81:     if (indices[i]) garray[ec++] = i;
 82:   }

 84:   /* make indices now point into garray */
 85:   for (i=0; i<ec; i++) {
 86:     indices[garray[i]] = i;
 87:   }

 89:   /* compact out the extra columns in B */
 90:   for (i=0; i<aij->B->m; i++) {
 91:     for (j=0; j<B->ilen[i]; j++) {
 92:       aj[B->i[i] + j] = indices[aj[B->i[i] + j]];
 93:     }
 94:   }
 95:   aij->B->n = aij->B->N = ec;
 96:   PetscFree(indices);
 97: #endif  
 98:   /* create local vector that is used to scatter into */
 99:   VecCreateSeq(PETSC_COMM_SELF,ec,&aij->lvec);

101:   /* create two temporary Index sets for build scatter gather */
102:   ISCreateGeneral(mat->comm,ec,garray,&from);
103:   ISCreateStride(PETSC_COMM_SELF,ec,0,1,&to);

105:   /* create temporary global vector to generate scatter context */
106:   /* this is inefficient, but otherwise we must do either 
107:      1) save garray until the first actual scatter when the vector is known or
108:      2) have another way of generating a scatter context without a vector.*/
109:   VecCreateMPI(mat->comm,mat->n,mat->N,&gvec);

111:   /* generate the scatter context */
112:   VecScatterCreate(gvec,from,aij->lvec,to,&aij->Mvctx);
113:   PetscLogObjectParent(mat,aij->Mvctx);
114:   PetscLogObjectParent(mat,aij->lvec);
115:   PetscLogObjectParent(mat,from);
116:   PetscLogObjectParent(mat,to);
117:   aij->garray = garray;
118:   PetscLogObjectMemory(mat,(ec+1)*sizeof(int));
119:   ISDestroy(from);
120:   ISDestroy(to);
121:   VecDestroy(gvec);
122:   return(0);
123: }


128: /*
129:      Takes the local part of an already assembled MPIAIJ matrix
130:    and disassembles it. This is to allow new nonzeros into the matrix
131:    that require more communication in the matrix vector multiply. 
132:    Thus certain data-structures must be rebuilt.

134:    Kind of slow! But that's what application programmers get when 
135:    they are sloppy.
136: */
137: int DisAssemble_MPIAIJ(Mat A)
138: {
139:   Mat_MPIAIJ   *aij = (Mat_MPIAIJ*)A->data;
140:   Mat          B = aij->B,Bnew;
141:   Mat_SeqAIJ   *Baij = (Mat_SeqAIJ*)B->data;
142:   int          ierr,i,j,m = B->m,n = A->N,col,ct = 0,*garray = aij->garray;
143:   int          *nz,ec;
144:   PetscScalar  v;

147:   /* free stuff related to matrix-vec multiply */
148:   VecGetSize(aij->lvec,&ec); /* needed for PetscLogObjectMemory below */
149:   VecDestroy(aij->lvec); aij->lvec = 0;
150:   VecScatterDestroy(aij->Mvctx); aij->Mvctx = 0;
151:   if (aij->colmap) {
152: #if defined (PETSC_USE_CTABLE)
153:     PetscTableDelete(aij->colmap);
154:     aij->colmap = 0;
155: #else
156:     PetscFree(aij->colmap);
157:     aij->colmap = 0;
158:     PetscLogObjectMemory(A,-aij->B->n*sizeof(int));
159: #endif
160:   }

162:   /* make sure that B is assembled so we can access its values */
163:   MatAssemblyBegin(B,MAT_FINAL_ASSEMBLY);
164:   MatAssemblyEnd(B,MAT_FINAL_ASSEMBLY);

166:   /* invent new B and copy stuff over */
167:   PetscMalloc((m+1)*sizeof(int),&nz);
168:   for (i=0; i<m; i++) {
169:     nz[i] = Baij->i[i+1] - Baij->i[i];
170:   }
171:   MatCreateSeqAIJ(PETSC_COMM_SELF,m,n,0,nz,&Bnew);
172:   PetscFree(nz);
173:   for (i=0; i<m; i++) {
174:     for (j=Baij->i[i]; j<Baij->i[i+1]; j++) {
175:       col  = garray[Baij->j[ct]];
176:       v    = Baij->a[ct++];
177:       MatSetValues(Bnew,1,&i,1,&col,&v,B->insertmode);
178:     }
179:   }
180:   PetscFree(aij->garray);
181:   aij->garray = 0;
182:   PetscLogObjectMemory(A,-ec*sizeof(int));
183:   MatDestroy(B);
184:   PetscLogObjectParent(A,Bnew);
185:   aij->B = Bnew;
186:   A->was_assembled = PETSC_FALSE;
187:   return(0);
188: }

190: /*      ugly stuff added for Glenn someday we should fix this up */

192: static int *auglyrmapd = 0,*auglyrmapo = 0;  /* mapping from the local ordering to the "diagonal" and "off-diagonal"
193:                                       parts of the local matrix */
194: static Vec auglydd = 0,auglyoo = 0;   /* work vectors used to scale the two parts of the local matrix */


199: int MatMPIAIJDiagonalScaleLocalSetUp(Mat inA,Vec scale)
200: {
201:   Mat_MPIAIJ  *ina = (Mat_MPIAIJ*) inA->data; /*access private part of matrix */
202:   int          ierr,i,n,nt,cstart,cend,no,*garray = ina->garray,*lindices;
203:   int          *r_rmapd,*r_rmapo;
204: 
206:   MatGetOwnershipRange(inA,&cstart,&cend);
207:   MatGetSize(ina->A,PETSC_NULL,&n);
208:   PetscMalloc((inA->mapping->n+1)*sizeof(int),&r_rmapd);
209:   PetscMemzero(r_rmapd,inA->mapping->n*sizeof(int));
210:   nt   = 0;
211:   for (i=0; i<inA->mapping->n; i++) {
212:     if (inA->mapping->indices[i] >= cstart && inA->mapping->indices[i] < cend) {
213:       nt++;
214:       r_rmapd[i] = inA->mapping->indices[i] + 1;
215:     }
216:   }
217:   if (nt != n) SETERRQ2(1,"Hmm nt %d n %d",nt,n);
218:   PetscMalloc((n+1)*sizeof(int),&auglyrmapd);
219:   for (i=0; i<inA->mapping->n; i++) {
220:     if (r_rmapd[i]){
221:       auglyrmapd[(r_rmapd[i]-1)-cstart] = i;
222:     }
223:   }
224:   PetscFree(r_rmapd);
225:   VecCreateSeq(PETSC_COMM_SELF,n,&auglydd);

227:   PetscMalloc((inA->N+1)*sizeof(int),&lindices);
228:   PetscMemzero(lindices,inA->N*sizeof(int));
229:   for (i=0; i<ina->B->n; i++) {
230:     lindices[garray[i]] = i+1;
231:   }
232:   no   = inA->mapping->n - nt;
233:   PetscMalloc((inA->mapping->n+1)*sizeof(int),&r_rmapo);
234:   PetscMemzero(r_rmapo,inA->mapping->n*sizeof(int));
235:   nt   = 0;
236:   for (i=0; i<inA->mapping->n; i++) {
237:     if (lindices[inA->mapping->indices[i]]) {
238:       nt++;
239:       r_rmapo[i] = lindices[inA->mapping->indices[i]];
240:     }
241:   }
242:   if (nt > no) SETERRQ2(1,"Hmm nt %d no %d",nt,n);
243:   PetscFree(lindices);
244:   PetscMalloc((nt+1)*sizeof(int),&auglyrmapo);
245:   for (i=0; i<inA->mapping->n; i++) {
246:     if (r_rmapo[i]){
247:       auglyrmapo[(r_rmapo[i]-1)] = i;
248:     }
249:   }
250:   PetscFree(r_rmapo);
251:   VecCreateSeq(PETSC_COMM_SELF,nt,&auglyoo);

253:   return(0);
254: }

258: int MatMPIAIJDiagonalScaleLocal(Mat A,Vec scale)
259: {
260:   /* This routine should really be abandoned as it duplicates MatDiagonalScaleLocal */
261:   int ierr,(*f)(Mat,Vec);

264:   PetscObjectQueryFunction((PetscObject)A,"MatDiagonalScaleLocal_C",(void (**)(void))&f);
265:   if (f) {
266:     (*f)(A,scale);
267:   }
268:   return(0);
269: }

271: EXTERN_C_BEGIN
274: int MatDiagonalScaleLocal_MPIAIJ(Mat A,Vec scale)
275: {
276:   Mat_MPIAIJ  *a = (Mat_MPIAIJ*) A->data; /*access private part of matrix */
277:   int         ierr,n,i;
278:   PetscScalar *d,*o,*s;
279: 
281:   if (!auglyrmapd) {
282:     MatMPIAIJDiagonalScaleLocalSetUp(A,scale);
283:   }

285:   VecGetArray(scale,&s);
286: 
287:   VecGetLocalSize(auglydd,&n);
288:   VecGetArray(auglydd,&d);
289:   for (i=0; i<n; i++) {
290:     d[i] = s[auglyrmapd[i]]; /* copy "diagonal" (true local) portion of scale into dd vector */
291:   }
292:   VecRestoreArray(auglydd,&d);
293:   /* column scale "diagonal" portion of local matrix */
294:   MatDiagonalScale(a->A,PETSC_NULL,auglydd);

296:   VecGetLocalSize(auglyoo,&n);
297:   VecGetArray(auglyoo,&o);
298:   for (i=0; i<n; i++) {
299:     o[i] = s[auglyrmapo[i]]; /* copy "off-diagonal" portion of scale into oo vector */
300:   }
301:   VecRestoreArray(scale,&s);
302:   VecRestoreArray(auglyoo,&o);
303:   /* column scale "off-diagonal" portion of local matrix */
304:   MatDiagonalScale(a->B,PETSC_NULL,auglyoo);

306:   return(0);
307: }
308: EXTERN_C_END