xref: /petsc/src/mat/impls/dense/mpi/mpidense.c (revision bb1d7374b64f295b2ed5ff23b89435d65e905a54)
1 
2 /*
3    Basic functions for basic parallel dense matrices.
4 */
5 
6 
7 #include <../src/mat/impls/dense/mpi/mpidense.h>    /*I   "petscmat.h"  I*/
8 #include <../src/mat/impls/aij/mpi/mpiaij.h>
9 
10 #undef __FUNCT__
11 #define __FUNCT__ "MatDenseGetLocalMatrix"
12 /*@
13 
14       MatDenseGetLocalMatrix - For a MATMPIDENSE or MATSEQDENSE matrix returns the sequential
15               matrix that represents the operator. For sequential matrices it returns itself.
16 
17     Input Parameter:
18 .      A - the Seq or MPI dense matrix
19 
20     Output Parameter:
21 .      B - the inner matrix
22 
23     Level: intermediate
24 
25 @*/
26 PetscErrorCode MatDenseGetLocalMatrix(Mat A,Mat *B)
27 {
28   Mat_MPIDense   *mat = (Mat_MPIDense*)A->data;
29   PetscErrorCode ierr;
30   PetscBool      flg;
31 
32   PetscFunctionBegin;
33   ierr = PetscObjectTypeCompare((PetscObject)A,MATMPIDENSE,&flg);CHKERRQ(ierr);
34   if (flg) *B = mat->A;
35   else *B = A;
36   PetscFunctionReturn(0);
37 }
38 
39 #undef __FUNCT__
40 #define __FUNCT__ "MatGetRow_MPIDense"
41 PetscErrorCode MatGetRow_MPIDense(Mat A,PetscInt row,PetscInt *nz,PetscInt **idx,PetscScalar **v)
42 {
43   Mat_MPIDense   *mat = (Mat_MPIDense*)A->data;
44   PetscErrorCode ierr;
45   PetscInt       lrow,rstart = A->rmap->rstart,rend = A->rmap->rend;
46 
47   PetscFunctionBegin;
48   if (row < rstart || row >= rend) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_SUP,"only local rows");
49   lrow = row - rstart;
50   ierr = MatGetRow(mat->A,lrow,nz,(const PetscInt**)idx,(const PetscScalar**)v);CHKERRQ(ierr);
51   PetscFunctionReturn(0);
52 }
53 
54 #undef __FUNCT__
55 #define __FUNCT__ "MatRestoreRow_MPIDense"
56 PetscErrorCode MatRestoreRow_MPIDense(Mat mat,PetscInt row,PetscInt *nz,PetscInt **idx,PetscScalar **v)
57 {
58   PetscErrorCode ierr;
59 
60   PetscFunctionBegin;
61   if (idx) {ierr = PetscFree(*idx);CHKERRQ(ierr);}
62   if (v) {ierr = PetscFree(*v);CHKERRQ(ierr);}
63   PetscFunctionReturn(0);
64 }
65 
66 #undef __FUNCT__
67 #define __FUNCT__ "MatGetDiagonalBlock_MPIDense"
68 PetscErrorCode  MatGetDiagonalBlock_MPIDense(Mat A,Mat *a)
69 {
70   Mat_MPIDense   *mdn = (Mat_MPIDense*)A->data;
71   PetscErrorCode ierr;
72   PetscInt       m = A->rmap->n,rstart = A->rmap->rstart;
73   PetscScalar    *array;
74   MPI_Comm       comm;
75   Mat            B;
76 
77   PetscFunctionBegin;
78   if (A->rmap->N != A->cmap->N) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_SUP,"Only square matrices supported.");
79 
80   ierr = PetscObjectQuery((PetscObject)A,"DiagonalBlock",(PetscObject*)&B);CHKERRQ(ierr);
81   if (!B) {
82     ierr = PetscObjectGetComm((PetscObject)(mdn->A),&comm);CHKERRQ(ierr);
83     ierr = MatCreate(comm,&B);CHKERRQ(ierr);
84     ierr = MatSetSizes(B,m,m,m,m);CHKERRQ(ierr);
85     ierr = MatSetType(B,((PetscObject)mdn->A)->type_name);CHKERRQ(ierr);
86     ierr = MatDenseGetArray(mdn->A,&array);CHKERRQ(ierr);
87     ierr = MatSeqDenseSetPreallocation(B,array+m*rstart);CHKERRQ(ierr);
88     ierr = MatDenseRestoreArray(mdn->A,&array);CHKERRQ(ierr);
89     ierr = MatAssemblyBegin(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
90     ierr = MatAssemblyEnd(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
91     ierr = PetscObjectCompose((PetscObject)A,"DiagonalBlock",(PetscObject)B);CHKERRQ(ierr);
92     *a   = B;
93     ierr = MatDestroy(&B);CHKERRQ(ierr);
94   } else *a = B;
95   PetscFunctionReturn(0);
96 }
97 
98 #undef __FUNCT__
99 #define __FUNCT__ "MatSetValues_MPIDense"
100 PetscErrorCode MatSetValues_MPIDense(Mat mat,PetscInt m,const PetscInt idxm[],PetscInt n,const PetscInt idxn[],const PetscScalar v[],InsertMode addv)
101 {
102   Mat_MPIDense   *A = (Mat_MPIDense*)mat->data;
103   PetscErrorCode ierr;
104   PetscInt       i,j,rstart = mat->rmap->rstart,rend = mat->rmap->rend,row;
105   PetscBool      roworiented = A->roworiented;
106 
107   PetscFunctionBegin;
108   for (i=0; i<m; i++) {
109     if (idxm[i] < 0) continue;
110     if (idxm[i] >= mat->rmap->N) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Row too large");
111     if (idxm[i] >= rstart && idxm[i] < rend) {
112       row = idxm[i] - rstart;
113       if (roworiented) {
114         ierr = MatSetValues(A->A,1,&row,n,idxn,v+i*n,addv);CHKERRQ(ierr);
115       } else {
116         for (j=0; j<n; j++) {
117           if (idxn[j] < 0) continue;
118           if (idxn[j] >= mat->cmap->N) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Column too large");
119           ierr = MatSetValues(A->A,1,&row,1,&idxn[j],v+i+j*m,addv);CHKERRQ(ierr);
120         }
121       }
122     } else if (!A->donotstash) {
123       mat->assembled = PETSC_FALSE;
124       if (roworiented) {
125         ierr = MatStashValuesRow_Private(&mat->stash,idxm[i],n,idxn,v+i*n,PETSC_FALSE);CHKERRQ(ierr);
126       } else {
127         ierr = MatStashValuesCol_Private(&mat->stash,idxm[i],n,idxn,v+i,m,PETSC_FALSE);CHKERRQ(ierr);
128       }
129     }
130   }
131   PetscFunctionReturn(0);
132 }
133 
134 #undef __FUNCT__
135 #define __FUNCT__ "MatGetValues_MPIDense"
136 PetscErrorCode MatGetValues_MPIDense(Mat mat,PetscInt m,const PetscInt idxm[],PetscInt n,const PetscInt idxn[],PetscScalar v[])
137 {
138   Mat_MPIDense   *mdn = (Mat_MPIDense*)mat->data;
139   PetscErrorCode ierr;
140   PetscInt       i,j,rstart = mat->rmap->rstart,rend = mat->rmap->rend,row;
141 
142   PetscFunctionBegin;
143   for (i=0; i<m; i++) {
144     if (idxm[i] < 0) continue; /* SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Negative row"); */
145     if (idxm[i] >= mat->rmap->N) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Row too large");
146     if (idxm[i] >= rstart && idxm[i] < rend) {
147       row = idxm[i] - rstart;
148       for (j=0; j<n; j++) {
149         if (idxn[j] < 0) continue; /* SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Negative column"); */
150         if (idxn[j] >= mat->cmap->N) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Column too large");
151         ierr = MatGetValues(mdn->A,1,&row,1,&idxn[j],v+i*n+j);CHKERRQ(ierr);
152       }
153     } else SETERRQ(PETSC_COMM_SELF,PETSC_ERR_SUP,"Only local values currently supported");
154   }
155   PetscFunctionReturn(0);
156 }
157 
158 #undef __FUNCT__
159 #define __FUNCT__ "MatDenseGetArray_MPIDense"
160 PetscErrorCode MatDenseGetArray_MPIDense(Mat A,PetscScalar *array[])
161 {
162   Mat_MPIDense   *a = (Mat_MPIDense*)A->data;
163   PetscErrorCode ierr;
164 
165   PetscFunctionBegin;
166   ierr = MatDenseGetArray(a->A,array);CHKERRQ(ierr);
167   PetscFunctionReturn(0);
168 }
169 
170 #undef __FUNCT__
171 #define __FUNCT__ "MatGetSubMatrix_MPIDense"
172 static PetscErrorCode MatGetSubMatrix_MPIDense(Mat A,IS isrow,IS iscol,MatReuse scall,Mat *B)
173 {
174   Mat_MPIDense   *mat  = (Mat_MPIDense*)A->data,*newmatd;
175   Mat_SeqDense   *lmat = (Mat_SeqDense*)mat->A->data;
176   PetscErrorCode ierr;
177   PetscInt       i,j,rstart,rend,nrows,ncols,Ncols,nlrows,nlcols;
178   const PetscInt *irow,*icol;
179   PetscScalar    *av,*bv,*v = lmat->v;
180   Mat            newmat;
181   IS             iscol_local;
182 
183   PetscFunctionBegin;
184   ierr = ISAllGather(iscol,&iscol_local);CHKERRQ(ierr);
185   ierr = ISGetIndices(isrow,&irow);CHKERRQ(ierr);
186   ierr = ISGetIndices(iscol_local,&icol);CHKERRQ(ierr);
187   ierr = ISGetLocalSize(isrow,&nrows);CHKERRQ(ierr);
188   ierr = ISGetLocalSize(iscol,&ncols);CHKERRQ(ierr);
189   ierr = ISGetSize(iscol,&Ncols);CHKERRQ(ierr); /* global number of columns, size of iscol_local */
190 
191   /* No parallel redistribution currently supported! Should really check each index set
192      to comfirm that it is OK.  ... Currently supports only submatrix same partitioning as
193      original matrix! */
194 
195   ierr = MatGetLocalSize(A,&nlrows,&nlcols);CHKERRQ(ierr);
196   ierr = MatGetOwnershipRange(A,&rstart,&rend);CHKERRQ(ierr);
197 
198   /* Check submatrix call */
199   if (scall == MAT_REUSE_MATRIX) {
200     /* SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_SIZ,"Reused submatrix wrong size"); */
201     /* Really need to test rows and column sizes! */
202     newmat = *B;
203   } else {
204     /* Create and fill new matrix */
205     ierr = MatCreate(PetscObjectComm((PetscObject)A),&newmat);CHKERRQ(ierr);
206     ierr = MatSetSizes(newmat,nrows,ncols,PETSC_DECIDE,Ncols);CHKERRQ(ierr);
207     ierr = MatSetType(newmat,((PetscObject)A)->type_name);CHKERRQ(ierr);
208     ierr = MatMPIDenseSetPreallocation(newmat,NULL);CHKERRQ(ierr);
209   }
210 
211   /* Now extract the data pointers and do the copy, column at a time */
212   newmatd = (Mat_MPIDense*)newmat->data;
213   bv      = ((Mat_SeqDense*)newmatd->A->data)->v;
214 
215   for (i=0; i<Ncols; i++) {
216     av = v + ((Mat_SeqDense*)mat->A->data)->lda*icol[i];
217     for (j=0; j<nrows; j++) {
218       *bv++ = av[irow[j] - rstart];
219     }
220   }
221 
222   /* Assemble the matrices so that the correct flags are set */
223   ierr = MatAssemblyBegin(newmat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
224   ierr = MatAssemblyEnd(newmat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
225 
226   /* Free work space */
227   ierr = ISRestoreIndices(isrow,&irow);CHKERRQ(ierr);
228   ierr = ISRestoreIndices(iscol_local,&icol);CHKERRQ(ierr);
229   ierr = ISDestroy(&iscol_local);CHKERRQ(ierr);
230   *B   = newmat;
231   PetscFunctionReturn(0);
232 }
233 
234 #undef __FUNCT__
235 #define __FUNCT__ "MatDenseRestoreArray_MPIDense"
236 PetscErrorCode MatDenseRestoreArray_MPIDense(Mat A,PetscScalar *array[])
237 {
238   Mat_MPIDense   *a = (Mat_MPIDense*)A->data;
239   PetscErrorCode ierr;
240 
241   PetscFunctionBegin;
242   ierr = MatDenseRestoreArray(a->A,array);CHKERRQ(ierr);
243   PetscFunctionReturn(0);
244 }
245 
246 #undef __FUNCT__
247 #define __FUNCT__ "MatAssemblyBegin_MPIDense"
248 PetscErrorCode MatAssemblyBegin_MPIDense(Mat mat,MatAssemblyType mode)
249 {
250   Mat_MPIDense   *mdn = (Mat_MPIDense*)mat->data;
251   MPI_Comm       comm;
252   PetscErrorCode ierr;
253   PetscInt       nstash,reallocs;
254   InsertMode     addv;
255 
256   PetscFunctionBegin;
257   ierr = PetscObjectGetComm((PetscObject)mat,&comm);CHKERRQ(ierr);
258   /* make sure all processors are either in INSERTMODE or ADDMODE */
259   ierr = MPI_Allreduce((PetscEnum*)&mat->insertmode,(PetscEnum*)&addv,1,MPIU_ENUM,MPI_BOR,comm);CHKERRQ(ierr);
260   if (addv == (ADD_VALUES|INSERT_VALUES)) SETERRQ(PetscObjectComm((PetscObject)mat),PETSC_ERR_ARG_WRONGSTATE,"Cannot mix adds/inserts on different procs");
261   mat->insertmode = addv; /* in case this processor had no cache */
262 
263   ierr = MatStashScatterBegin_Private(mat,&mat->stash,mat->rmap->range);CHKERRQ(ierr);
264   ierr = MatStashGetInfo_Private(&mat->stash,&nstash,&reallocs);CHKERRQ(ierr);
265   ierr = PetscInfo2(mdn->A,"Stash has %D entries, uses %D mallocs.\n",nstash,reallocs);CHKERRQ(ierr);
266   PetscFunctionReturn(0);
267 }
268 
269 #undef __FUNCT__
270 #define __FUNCT__ "MatAssemblyEnd_MPIDense"
271 PetscErrorCode MatAssemblyEnd_MPIDense(Mat mat,MatAssemblyType mode)
272 {
273   Mat_MPIDense   *mdn=(Mat_MPIDense*)mat->data;
274   PetscErrorCode ierr;
275   PetscInt       i,*row,*col,flg,j,rstart,ncols;
276   PetscMPIInt    n;
277   PetscScalar    *val;
278 
279   PetscFunctionBegin;
280   /*  wait on receives */
281   while (1) {
282     ierr = MatStashScatterGetMesg_Private(&mat->stash,&n,&row,&col,&val,&flg);CHKERRQ(ierr);
283     if (!flg) break;
284 
285     for (i=0; i<n;) {
286       /* Now identify the consecutive vals belonging to the same row */
287       for (j=i,rstart=row[j]; j<n; j++) {
288         if (row[j] != rstart) break;
289       }
290       if (j < n) ncols = j-i;
291       else       ncols = n-i;
292       /* Now assemble all these values with a single function call */
293       ierr = MatSetValues_MPIDense(mat,1,row+i,ncols,col+i,val+i,mat->insertmode);CHKERRQ(ierr);
294       i    = j;
295     }
296   }
297   ierr = MatStashScatterEnd_Private(&mat->stash);CHKERRQ(ierr);
298 
299   ierr = MatAssemblyBegin(mdn->A,mode);CHKERRQ(ierr);
300   ierr = MatAssemblyEnd(mdn->A,mode);CHKERRQ(ierr);
301 
302   if (!mat->was_assembled && mode == MAT_FINAL_ASSEMBLY) {
303     ierr = MatSetUpMultiply_MPIDense(mat);CHKERRQ(ierr);
304   }
305   PetscFunctionReturn(0);
306 }
307 
308 #undef __FUNCT__
309 #define __FUNCT__ "MatZeroEntries_MPIDense"
310 PetscErrorCode MatZeroEntries_MPIDense(Mat A)
311 {
312   PetscErrorCode ierr;
313   Mat_MPIDense   *l = (Mat_MPIDense*)A->data;
314 
315   PetscFunctionBegin;
316   ierr = MatZeroEntries(l->A);CHKERRQ(ierr);
317   PetscFunctionReturn(0);
318 }
319 
320 /* the code does not do the diagonal entries correctly unless the
321    matrix is square and the column and row owerships are identical.
322    This is a BUG. The only way to fix it seems to be to access
323    mdn->A and mdn->B directly and not through the MatZeroRows()
324    routine.
325 */
326 #undef __FUNCT__
327 #define __FUNCT__ "MatZeroRows_MPIDense"
328 PetscErrorCode MatZeroRows_MPIDense(Mat A,PetscInt N,const PetscInt rows[],PetscScalar diag,Vec x,Vec b)
329 {
330   Mat_MPIDense      *l = (Mat_MPIDense*)A->data;
331   PetscErrorCode    ierr;
332   PetscInt          i,*owners = A->rmap->range;
333   PetscInt          *sizes,j,idx,nsends;
334   PetscInt          nmax,*svalues,*starts,*owner,nrecvs;
335   PetscInt          *rvalues,tag = ((PetscObject)A)->tag,count,base,slen,*source;
336   PetscInt          *lens,*lrows,*values;
337   PetscMPIInt       n,imdex,rank = l->rank,size = l->size;
338   MPI_Comm          comm;
339   MPI_Request       *send_waits,*recv_waits;
340   MPI_Status        recv_status,*send_status;
341   PetscBool         found;
342   const PetscScalar *xx;
343   PetscScalar       *bb;
344 
345   PetscFunctionBegin;
346   ierr = PetscObjectGetComm((PetscObject)A,&comm);CHKERRQ(ierr);
347   if (A->rmap->N != A->cmap->N) SETERRQ(comm,PETSC_ERR_SUP,"Only handles square matrices");
348   if (A->rmap->n != A->cmap->n) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_SUP,"Only handles matrices with identical column and row ownership");
349   /*  first count number of contributors to each processor */
350   ierr = PetscCalloc1(2*size,&sizes);CHKERRQ(ierr);
351   ierr = PetscMalloc1(N+1,&owner);CHKERRQ(ierr);  /* see note*/
352   for (i=0; i<N; i++) {
353     idx   = rows[i];
354     found = PETSC_FALSE;
355     for (j=0; j<size; j++) {
356       if (idx >= owners[j] && idx < owners[j+1]) {
357         sizes[2*j]++; sizes[2*j+1] = 1; owner[i] = j; found = PETSC_TRUE; break;
358       }
359     }
360     if (!found) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Index out of range");
361   }
362   nsends = 0;
363   for (i=0; i<size; i++) nsends += sizes[2*i+1];
364 
365   /* inform other processors of number of messages and max length*/
366   ierr = PetscMaxSum(comm,sizes,&nmax,&nrecvs);CHKERRQ(ierr);
367 
368   /* post receives:   */
369   ierr = PetscMalloc1((nrecvs+1)*(nmax+1),&rvalues);CHKERRQ(ierr);
370   ierr = PetscMalloc1(nrecvs+1,&recv_waits);CHKERRQ(ierr);
371   for (i=0; i<nrecvs; i++) {
372     ierr = MPI_Irecv(rvalues+nmax*i,nmax,MPIU_INT,MPI_ANY_SOURCE,tag,comm,recv_waits+i);CHKERRQ(ierr);
373   }
374 
375   /* do sends:
376       1) starts[i] gives the starting index in svalues for stuff going to
377          the ith processor
378   */
379   ierr = PetscMalloc1(N+1,&svalues);CHKERRQ(ierr);
380   ierr = PetscMalloc1(nsends+1,&send_waits);CHKERRQ(ierr);
381   ierr = PetscMalloc1(size+1,&starts);CHKERRQ(ierr);
382 
383   starts[0] = 0;
384   for (i=1; i<size; i++) starts[i] = starts[i-1] + sizes[2*i-2];
385   for (i=0; i<N; i++) svalues[starts[owner[i]]++] = rows[i];
386 
387   starts[0] = 0;
388   for (i=1; i<size+1; i++) starts[i] = starts[i-1] + sizes[2*i-2];
389   count = 0;
390   for (i=0; i<size; i++) {
391     if (sizes[2*i+1]) {
392       ierr = MPI_Isend(svalues+starts[i],sizes[2*i],MPIU_INT,i,tag,comm,send_waits+count++);CHKERRQ(ierr);
393     }
394   }
395   ierr = PetscFree(starts);CHKERRQ(ierr);
396 
397   base = owners[rank];
398 
399   /*  wait on receives */
400   ierr  = PetscMalloc2(nrecvs,&lens,nrecvs,&source);CHKERRQ(ierr);
401   count = nrecvs;
402   slen  = 0;
403   while (count) {
404     ierr = MPI_Waitany(nrecvs,recv_waits,&imdex,&recv_status);CHKERRQ(ierr);
405     /* unpack receives into our local space */
406     ierr = MPI_Get_count(&recv_status,MPIU_INT,&n);CHKERRQ(ierr);
407 
408     source[imdex] = recv_status.MPI_SOURCE;
409     lens[imdex]   = n;
410     slen += n;
411     count--;
412   }
413   ierr = PetscFree(recv_waits);CHKERRQ(ierr);
414 
415   /* move the data into the send scatter */
416   ierr  = PetscMalloc1(slen+1,&lrows);CHKERRQ(ierr);
417   count = 0;
418   for (i=0; i<nrecvs; i++) {
419     values = rvalues + i*nmax;
420     for (j=0; j<lens[i]; j++) {
421       lrows[count++] = values[j] - base;
422     }
423   }
424   ierr = PetscFree(rvalues);CHKERRQ(ierr);
425   ierr = PetscFree2(lens,source);CHKERRQ(ierr);
426   ierr = PetscFree(owner);CHKERRQ(ierr);
427   ierr = PetscFree(sizes);CHKERRQ(ierr);
428 
429   /* fix right hand side if needed */
430   if (x && b) {
431     ierr = VecGetArrayRead(x,&xx);CHKERRQ(ierr);
432     ierr = VecGetArray(b,&bb);CHKERRQ(ierr);
433     for (i=0; i<slen; i++) {
434       bb[lrows[i]] = diag*xx[lrows[i]];
435     }
436     ierr = VecRestoreArrayRead(x,&xx);CHKERRQ(ierr);
437     ierr = VecRestoreArray(b,&bb);CHKERRQ(ierr);
438   }
439 
440   /* actually zap the local rows */
441   ierr = MatZeroRows(l->A,slen,lrows,0.0,0,0);CHKERRQ(ierr);
442   if (diag != 0.0) {
443     Mat_SeqDense *ll = (Mat_SeqDense*)l->A->data;
444     PetscInt     m   = ll->lda, i;
445 
446     for (i=0; i<slen; i++) {
447       ll->v[lrows[i] + m*(A->cmap->rstart + lrows[i])] = diag;
448     }
449   }
450   ierr = PetscFree(lrows);CHKERRQ(ierr);
451 
452   /* wait on sends */
453   if (nsends) {
454     ierr = PetscMalloc1(nsends,&send_status);CHKERRQ(ierr);
455     ierr = MPI_Waitall(nsends,send_waits,send_status);CHKERRQ(ierr);
456     ierr = PetscFree(send_status);CHKERRQ(ierr);
457   }
458   ierr = PetscFree(send_waits);CHKERRQ(ierr);
459   ierr = PetscFree(svalues);CHKERRQ(ierr);
460   PetscFunctionReturn(0);
461 }
462 
463 #undef __FUNCT__
464 #define __FUNCT__ "MatMult_MPIDense"
465 PetscErrorCode MatMult_MPIDense(Mat mat,Vec xx,Vec yy)
466 {
467   Mat_MPIDense   *mdn = (Mat_MPIDense*)mat->data;
468   PetscErrorCode ierr;
469 
470   PetscFunctionBegin;
471   ierr = VecScatterBegin(mdn->Mvctx,xx,mdn->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
472   ierr = VecScatterEnd(mdn->Mvctx,xx,mdn->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
473   ierr = MatMult_SeqDense(mdn->A,mdn->lvec,yy);CHKERRQ(ierr);
474   PetscFunctionReturn(0);
475 }
476 
477 #undef __FUNCT__
478 #define __FUNCT__ "MatMultAdd_MPIDense"
479 PetscErrorCode MatMultAdd_MPIDense(Mat mat,Vec xx,Vec yy,Vec zz)
480 {
481   Mat_MPIDense   *mdn = (Mat_MPIDense*)mat->data;
482   PetscErrorCode ierr;
483 
484   PetscFunctionBegin;
485   ierr = VecScatterBegin(mdn->Mvctx,xx,mdn->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
486   ierr = VecScatterEnd(mdn->Mvctx,xx,mdn->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
487   ierr = MatMultAdd_SeqDense(mdn->A,mdn->lvec,yy,zz);CHKERRQ(ierr);
488   PetscFunctionReturn(0);
489 }
490 
491 #undef __FUNCT__
492 #define __FUNCT__ "MatMultTranspose_MPIDense"
493 PetscErrorCode MatMultTranspose_MPIDense(Mat A,Vec xx,Vec yy)
494 {
495   Mat_MPIDense   *a = (Mat_MPIDense*)A->data;
496   PetscErrorCode ierr;
497   PetscScalar    zero = 0.0;
498 
499   PetscFunctionBegin;
500   ierr = VecSet(yy,zero);CHKERRQ(ierr);
501   ierr = MatMultTranspose_SeqDense(a->A,xx,a->lvec);CHKERRQ(ierr);
502   ierr = VecScatterBegin(a->Mvctx,a->lvec,yy,ADD_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
503   ierr = VecScatterEnd(a->Mvctx,a->lvec,yy,ADD_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
504   PetscFunctionReturn(0);
505 }
506 
507 #undef __FUNCT__
508 #define __FUNCT__ "MatMultTransposeAdd_MPIDense"
509 PetscErrorCode MatMultTransposeAdd_MPIDense(Mat A,Vec xx,Vec yy,Vec zz)
510 {
511   Mat_MPIDense   *a = (Mat_MPIDense*)A->data;
512   PetscErrorCode ierr;
513 
514   PetscFunctionBegin;
515   ierr = VecCopy(yy,zz);CHKERRQ(ierr);
516   ierr = MatMultTranspose_SeqDense(a->A,xx,a->lvec);CHKERRQ(ierr);
517   ierr = VecScatterBegin(a->Mvctx,a->lvec,zz,ADD_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
518   ierr = VecScatterEnd(a->Mvctx,a->lvec,zz,ADD_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
519   PetscFunctionReturn(0);
520 }
521 
522 #undef __FUNCT__
523 #define __FUNCT__ "MatGetDiagonal_MPIDense"
524 PetscErrorCode MatGetDiagonal_MPIDense(Mat A,Vec v)
525 {
526   Mat_MPIDense   *a    = (Mat_MPIDense*)A->data;
527   Mat_SeqDense   *aloc = (Mat_SeqDense*)a->A->data;
528   PetscErrorCode ierr;
529   PetscInt       len,i,n,m = A->rmap->n,radd;
530   PetscScalar    *x,zero = 0.0;
531 
532   PetscFunctionBegin;
533   ierr = VecSet(v,zero);CHKERRQ(ierr);
534   ierr = VecGetArray(v,&x);CHKERRQ(ierr);
535   ierr = VecGetSize(v,&n);CHKERRQ(ierr);
536   if (n != A->rmap->N) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_SIZ,"Nonconforming mat and vec");
537   len  = PetscMin(a->A->rmap->n,a->A->cmap->n);
538   radd = A->rmap->rstart*m;
539   for (i=0; i<len; i++) {
540     x[i] = aloc->v[radd + i*m + i];
541   }
542   ierr = VecRestoreArray(v,&x);CHKERRQ(ierr);
543   PetscFunctionReturn(0);
544 }
545 
546 #undef __FUNCT__
547 #define __FUNCT__ "MatDestroy_MPIDense"
548 PetscErrorCode MatDestroy_MPIDense(Mat mat)
549 {
550   Mat_MPIDense   *mdn = (Mat_MPIDense*)mat->data;
551   PetscErrorCode ierr;
552 
553   PetscFunctionBegin;
554 #if defined(PETSC_USE_LOG)
555   PetscLogObjectState((PetscObject)mat,"Rows=%D, Cols=%D",mat->rmap->N,mat->cmap->N);
556 #endif
557   ierr = MatStashDestroy_Private(&mat->stash);CHKERRQ(ierr);
558   ierr = MatDestroy(&mdn->A);CHKERRQ(ierr);
559   ierr = VecDestroy(&mdn->lvec);CHKERRQ(ierr);
560   ierr = VecScatterDestroy(&mdn->Mvctx);CHKERRQ(ierr);
561 
562   ierr = PetscFree(mat->data);CHKERRQ(ierr);
563   ierr = PetscObjectChangeTypeName((PetscObject)mat,0);CHKERRQ(ierr);
564 
565   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatDenseGetArray_C",NULL);CHKERRQ(ierr);
566   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatDenseRestoreArray_C",NULL);CHKERRQ(ierr);
567 #if defined(PETSC_HAVE_ELEMENTAL)
568   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatConvert_mpidense_elemental_C",NULL);CHKERRQ(ierr);
569 #endif
570   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatGetDiagonalBlock_C",NULL);CHKERRQ(ierr);
571   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatMPIDenseSetPreallocation_C",NULL);CHKERRQ(ierr);
572   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatMatMult_mpiaij_mpidense_C",NULL);CHKERRQ(ierr);
573   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatMatMultSymbolic_mpiaij_mpidense_C",NULL);CHKERRQ(ierr);
574   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatMatMultNumeric_mpiaij_mpidense_C",NULL);CHKERRQ(ierr);
575   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatTransposeMatMult_mpiaij_mpidense_C",NULL);CHKERRQ(ierr);
576   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatTransposeMatMultSymbolic_mpiaij_mpidense_C",NULL);CHKERRQ(ierr);
577   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatTransposeMatMultNumeric_mpiaij_mpidense_C",NULL);CHKERRQ(ierr);
578   PetscFunctionReturn(0);
579 }
580 
581 #undef __FUNCT__
582 #define __FUNCT__ "MatView_MPIDense_Binary"
583 static PetscErrorCode MatView_MPIDense_Binary(Mat mat,PetscViewer viewer)
584 {
585   Mat_MPIDense      *mdn = (Mat_MPIDense*)mat->data;
586   PetscErrorCode    ierr;
587   PetscViewerFormat format;
588   int               fd;
589   PetscInt          header[4],mmax,N = mat->cmap->N,i,j,m,k;
590   PetscMPIInt       rank,tag  = ((PetscObject)viewer)->tag,size;
591   PetscScalar       *work,*v,*vv;
592   Mat_SeqDense      *a = (Mat_SeqDense*)mdn->A->data;
593 
594   PetscFunctionBegin;
595   if (mdn->size == 1) {
596     ierr = MatView(mdn->A,viewer);CHKERRQ(ierr);
597   } else {
598     ierr = PetscViewerBinaryGetDescriptor(viewer,&fd);CHKERRQ(ierr);
599     ierr = MPI_Comm_rank(PetscObjectComm((PetscObject)mat),&rank);CHKERRQ(ierr);
600     ierr = MPI_Comm_size(PetscObjectComm((PetscObject)mat),&size);CHKERRQ(ierr);
601 
602     ierr = PetscViewerGetFormat(viewer,&format);CHKERRQ(ierr);
603     if (format == PETSC_VIEWER_NATIVE) {
604 
605       if (!rank) {
606         /* store the matrix as a dense matrix */
607         header[0] = MAT_FILE_CLASSID;
608         header[1] = mat->rmap->N;
609         header[2] = N;
610         header[3] = MATRIX_BINARY_FORMAT_DENSE;
611         ierr      = PetscBinaryWrite(fd,header,4,PETSC_INT,PETSC_TRUE);CHKERRQ(ierr);
612 
613         /* get largest work array needed for transposing array */
614         mmax = mat->rmap->n;
615         for (i=1; i<size; i++) {
616           mmax = PetscMax(mmax,mat->rmap->range[i+1] - mat->rmap->range[i]);
617         }
618         ierr = PetscMalloc1(mmax*N,&work);CHKERRQ(ierr);
619 
620         /* write out local array, by rows */
621         m = mat->rmap->n;
622         v = a->v;
623         for (j=0; j<N; j++) {
624           for (i=0; i<m; i++) {
625             work[j + i*N] = *v++;
626           }
627         }
628         ierr = PetscBinaryWrite(fd,work,m*N,PETSC_SCALAR,PETSC_FALSE);CHKERRQ(ierr);
629         /* get largest work array to receive messages from other processes, excludes process zero */
630         mmax = 0;
631         for (i=1; i<size; i++) {
632           mmax = PetscMax(mmax,mat->rmap->range[i+1] - mat->rmap->range[i]);
633         }
634         ierr = PetscMalloc1(mmax*N,&vv);CHKERRQ(ierr);
635         for (k = 1; k < size; k++) {
636           v    = vv;
637           m    = mat->rmap->range[k+1] - mat->rmap->range[k];
638           ierr = MPIULong_Recv(v,m*N,MPIU_SCALAR,k,tag,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
639 
640           for (j = 0; j < N; j++) {
641             for (i = 0; i < m; i++) {
642               work[j + i*N] = *v++;
643             }
644           }
645           ierr = PetscBinaryWrite(fd,work,m*N,PETSC_SCALAR,PETSC_FALSE);CHKERRQ(ierr);
646         }
647         ierr = PetscFree(work);CHKERRQ(ierr);
648         ierr = PetscFree(vv);CHKERRQ(ierr);
649       } else {
650         ierr = MPIULong_Send(a->v,mat->rmap->n*mat->cmap->N,MPIU_SCALAR,0,tag,PetscObjectComm((PetscObject)mat));CHKERRQ(ierr);
651       }
652     } else SETERRQ(PETSC_COMM_SELF,PETSC_ERR_SUP,"To store a parallel dense matrix you must first call PetscViewerSetFormat(viewer,PETSC_VIEWER_NATIVE)");
653   }
654   PetscFunctionReturn(0);
655 }
656 
657 extern PetscErrorCode MatView_SeqDense(Mat,PetscViewer);
658 #include <petscdraw.h>
659 #undef __FUNCT__
660 #define __FUNCT__ "MatView_MPIDense_ASCIIorDraworSocket"
661 static PetscErrorCode MatView_MPIDense_ASCIIorDraworSocket(Mat mat,PetscViewer viewer)
662 {
663   Mat_MPIDense      *mdn = (Mat_MPIDense*)mat->data;
664   PetscErrorCode    ierr;
665   PetscMPIInt       rank = mdn->rank;
666   PetscViewerType   vtype;
667   PetscBool         iascii,isdraw;
668   PetscViewer       sviewer;
669   PetscViewerFormat format;
670 
671   PetscFunctionBegin;
672   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERASCII,&iascii);CHKERRQ(ierr);
673   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERDRAW,&isdraw);CHKERRQ(ierr);
674   if (iascii) {
675     ierr = PetscViewerGetType(viewer,&vtype);CHKERRQ(ierr);
676     ierr = PetscViewerGetFormat(viewer,&format);CHKERRQ(ierr);
677     if (format == PETSC_VIEWER_ASCII_INFO_DETAIL) {
678       MatInfo info;
679       ierr = MatGetInfo(mat,MAT_LOCAL,&info);CHKERRQ(ierr);
680       ierr = PetscViewerASCIIPushSynchronized(viewer);CHKERRQ(ierr);
681       ierr = PetscViewerASCIISynchronizedPrintf(viewer,"  [%d] local rows %D nz %D nz alloced %D mem %D \n",rank,mat->rmap->n,(PetscInt)info.nz_used,(PetscInt)info.nz_allocated,(PetscInt)info.memory);CHKERRQ(ierr);
682       ierr = PetscViewerFlush(viewer);CHKERRQ(ierr);
683       ierr = PetscViewerASCIIPopSynchronized(viewer);CHKERRQ(ierr);
684       ierr = VecScatterView(mdn->Mvctx,viewer);CHKERRQ(ierr);
685       PetscFunctionReturn(0);
686     } else if (format == PETSC_VIEWER_ASCII_INFO) {
687       PetscFunctionReturn(0);
688     }
689   } else if (isdraw) {
690     PetscDraw draw;
691     PetscBool isnull;
692 
693     ierr = PetscViewerDrawGetDraw(viewer,0,&draw);CHKERRQ(ierr);
694     ierr = PetscDrawIsNull(draw,&isnull);CHKERRQ(ierr);
695     if (isnull) PetscFunctionReturn(0);
696   }
697 
698   {
699     /* assemble the entire matrix onto first processor. */
700     Mat         A;
701     PetscInt    M = mat->rmap->N,N = mat->cmap->N,m,row,i,nz;
702     PetscInt    *cols;
703     PetscScalar *vals;
704 
705     ierr = MatCreate(PetscObjectComm((PetscObject)mat),&A);CHKERRQ(ierr);
706     if (!rank) {
707       ierr = MatSetSizes(A,M,N,M,N);CHKERRQ(ierr);
708     } else {
709       ierr = MatSetSizes(A,0,0,M,N);CHKERRQ(ierr);
710     }
711     /* Since this is a temporary matrix, MATMPIDENSE instead of ((PetscObject)A)->type_name here is probably acceptable. */
712     ierr = MatSetType(A,MATMPIDENSE);CHKERRQ(ierr);
713     ierr = MatMPIDenseSetPreallocation(A,NULL);CHKERRQ(ierr);
714     ierr = PetscLogObjectParent((PetscObject)mat,(PetscObject)A);CHKERRQ(ierr);
715 
716     /* Copy the matrix ... This isn't the most efficient means,
717        but it's quick for now */
718     A->insertmode = INSERT_VALUES;
719 
720     row = mat->rmap->rstart;
721     m   = mdn->A->rmap->n;
722     for (i=0; i<m; i++) {
723       ierr = MatGetRow_MPIDense(mat,row,&nz,&cols,&vals);CHKERRQ(ierr);
724       ierr = MatSetValues_MPIDense(A,1,&row,nz,cols,vals,INSERT_VALUES);CHKERRQ(ierr);
725       ierr = MatRestoreRow_MPIDense(mat,row,&nz,&cols,&vals);CHKERRQ(ierr);
726       row++;
727     }
728 
729     ierr = MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
730     ierr = MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
731     ierr = PetscViewerGetSubViewer(viewer,PETSC_COMM_SELF,&sviewer);CHKERRQ(ierr);
732     if (!rank) {
733         ierr = MatView_SeqDense(((Mat_MPIDense*)(A->data))->A,sviewer);CHKERRQ(ierr);
734     }
735     ierr = PetscViewerRestoreSubViewer(viewer,PETSC_COMM_SELF,&sviewer);CHKERRQ(ierr);
736     ierr = PetscViewerFlush(viewer);CHKERRQ(ierr);
737     ierr = MatDestroy(&A);CHKERRQ(ierr);
738   }
739   PetscFunctionReturn(0);
740 }
741 
742 #undef __FUNCT__
743 #define __FUNCT__ "MatView_MPIDense"
744 PetscErrorCode MatView_MPIDense(Mat mat,PetscViewer viewer)
745 {
746   PetscErrorCode ierr;
747   PetscBool      iascii,isbinary,isdraw,issocket;
748 
749   PetscFunctionBegin;
750   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERASCII,&iascii);CHKERRQ(ierr);
751   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERBINARY,&isbinary);CHKERRQ(ierr);
752   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERSOCKET,&issocket);CHKERRQ(ierr);
753   ierr = PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERDRAW,&isdraw);CHKERRQ(ierr);
754 
755   if (iascii || issocket || isdraw) {
756     ierr = MatView_MPIDense_ASCIIorDraworSocket(mat,viewer);CHKERRQ(ierr);
757   } else if (isbinary) {
758     ierr = MatView_MPIDense_Binary(mat,viewer);CHKERRQ(ierr);
759   }
760   PetscFunctionReturn(0);
761 }
762 
763 #undef __FUNCT__
764 #define __FUNCT__ "MatGetInfo_MPIDense"
765 PetscErrorCode MatGetInfo_MPIDense(Mat A,MatInfoType flag,MatInfo *info)
766 {
767   Mat_MPIDense   *mat = (Mat_MPIDense*)A->data;
768   Mat            mdn  = mat->A;
769   PetscErrorCode ierr;
770   PetscReal      isend[5],irecv[5];
771 
772   PetscFunctionBegin;
773   info->block_size = 1.0;
774 
775   ierr = MatGetInfo(mdn,MAT_LOCAL,info);CHKERRQ(ierr);
776 
777   isend[0] = info->nz_used; isend[1] = info->nz_allocated; isend[2] = info->nz_unneeded;
778   isend[3] = info->memory;  isend[4] = info->mallocs;
779   if (flag == MAT_LOCAL) {
780     info->nz_used      = isend[0];
781     info->nz_allocated = isend[1];
782     info->nz_unneeded  = isend[2];
783     info->memory       = isend[3];
784     info->mallocs      = isend[4];
785   } else if (flag == MAT_GLOBAL_MAX) {
786     ierr = MPI_Allreduce(isend,irecv,5,MPIU_REAL,MPIU_MAX,PetscObjectComm((PetscObject)A));CHKERRQ(ierr);
787 
788     info->nz_used      = irecv[0];
789     info->nz_allocated = irecv[1];
790     info->nz_unneeded  = irecv[2];
791     info->memory       = irecv[3];
792     info->mallocs      = irecv[4];
793   } else if (flag == MAT_GLOBAL_SUM) {
794     ierr = MPI_Allreduce(isend,irecv,5,MPIU_REAL,MPIU_SUM,PetscObjectComm((PetscObject)A));CHKERRQ(ierr);
795 
796     info->nz_used      = irecv[0];
797     info->nz_allocated = irecv[1];
798     info->nz_unneeded  = irecv[2];
799     info->memory       = irecv[3];
800     info->mallocs      = irecv[4];
801   }
802   info->fill_ratio_given  = 0; /* no parallel LU/ILU/Cholesky */
803   info->fill_ratio_needed = 0;
804   info->factor_mallocs    = 0;
805   PetscFunctionReturn(0);
806 }
807 
808 #undef __FUNCT__
809 #define __FUNCT__ "MatSetOption_MPIDense"
810 PetscErrorCode MatSetOption_MPIDense(Mat A,MatOption op,PetscBool flg)
811 {
812   Mat_MPIDense   *a = (Mat_MPIDense*)A->data;
813   PetscErrorCode ierr;
814 
815   PetscFunctionBegin;
816   switch (op) {
817   case MAT_NEW_NONZERO_LOCATIONS:
818   case MAT_NEW_NONZERO_LOCATION_ERR:
819   case MAT_NEW_NONZERO_ALLOCATION_ERR:
820     ierr = MatSetOption(a->A,op,flg);CHKERRQ(ierr);
821     break;
822   case MAT_ROW_ORIENTED:
823     a->roworiented = flg;
824 
825     ierr = MatSetOption(a->A,op,flg);CHKERRQ(ierr);
826     break;
827   case MAT_NEW_DIAGONALS:
828   case MAT_KEEP_NONZERO_PATTERN:
829   case MAT_USE_HASH_TABLE:
830     ierr = PetscInfo1(A,"Option %s ignored\n",MatOptions[op]);CHKERRQ(ierr);
831     break;
832   case MAT_IGNORE_OFF_PROC_ENTRIES:
833     a->donotstash = flg;
834     break;
835   case MAT_SYMMETRIC:
836   case MAT_STRUCTURALLY_SYMMETRIC:
837   case MAT_HERMITIAN:
838   case MAT_SYMMETRY_ETERNAL:
839   case MAT_IGNORE_LOWER_TRIANGULAR:
840     ierr = PetscInfo1(A,"Option %s ignored\n",MatOptions[op]);CHKERRQ(ierr);
841     break;
842   default:
843     SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_SUP,"unknown option %s",MatOptions[op]);
844   }
845   PetscFunctionReturn(0);
846 }
847 
848 
849 #undef __FUNCT__
850 #define __FUNCT__ "MatDiagonalScale_MPIDense"
851 PetscErrorCode MatDiagonalScale_MPIDense(Mat A,Vec ll,Vec rr)
852 {
853   Mat_MPIDense   *mdn = (Mat_MPIDense*)A->data;
854   Mat_SeqDense   *mat = (Mat_SeqDense*)mdn->A->data;
855   PetscScalar    *l,*r,x,*v;
856   PetscErrorCode ierr;
857   PetscInt       i,j,s2a,s3a,s2,s3,m=mdn->A->rmap->n,n=mdn->A->cmap->n;
858 
859   PetscFunctionBegin;
860   ierr = MatGetLocalSize(A,&s2,&s3);CHKERRQ(ierr);
861   if (ll) {
862     ierr = VecGetLocalSize(ll,&s2a);CHKERRQ(ierr);
863     if (s2a != s2) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_SIZ,"Left scaling vector non-conforming local size, %d != %d.", s2a, s2);
864     ierr = VecGetArray(ll,&l);CHKERRQ(ierr);
865     for (i=0; i<m; i++) {
866       x = l[i];
867       v = mat->v + i;
868       for (j=0; j<n; j++) { (*v) *= x; v+= m;}
869     }
870     ierr = VecRestoreArray(ll,&l);CHKERRQ(ierr);
871     ierr = PetscLogFlops(n*m);CHKERRQ(ierr);
872   }
873   if (rr) {
874     ierr = VecGetLocalSize(rr,&s3a);CHKERRQ(ierr);
875     if (s3a != s3) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_ARG_SIZ,"Right scaling vec non-conforming local size, %d != %d.", s3a, s3);
876     ierr = VecScatterBegin(mdn->Mvctx,rr,mdn->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
877     ierr = VecScatterEnd(mdn->Mvctx,rr,mdn->lvec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
878     ierr = VecGetArray(mdn->lvec,&r);CHKERRQ(ierr);
879     for (i=0; i<n; i++) {
880       x = r[i];
881       v = mat->v + i*m;
882       for (j=0; j<m; j++) (*v++) *= x;
883     }
884     ierr = VecRestoreArray(mdn->lvec,&r);CHKERRQ(ierr);
885     ierr = PetscLogFlops(n*m);CHKERRQ(ierr);
886   }
887   PetscFunctionReturn(0);
888 }
889 
890 #undef __FUNCT__
891 #define __FUNCT__ "MatNorm_MPIDense"
892 PetscErrorCode MatNorm_MPIDense(Mat A,NormType type,PetscReal *nrm)
893 {
894   Mat_MPIDense   *mdn = (Mat_MPIDense*)A->data;
895   Mat_SeqDense   *mat = (Mat_SeqDense*)mdn->A->data;
896   PetscErrorCode ierr;
897   PetscInt       i,j;
898   PetscReal      sum = 0.0;
899   PetscScalar    *v  = mat->v;
900 
901   PetscFunctionBegin;
902   if (mdn->size == 1) {
903     ierr =  MatNorm(mdn->A,type,nrm);CHKERRQ(ierr);
904   } else {
905     if (type == NORM_FROBENIUS) {
906       for (i=0; i<mdn->A->cmap->n*mdn->A->rmap->n; i++) {
907         sum += PetscRealPart(PetscConj(*v)*(*v)); v++;
908       }
909       ierr = MPI_Allreduce(&sum,nrm,1,MPIU_REAL,MPIU_SUM,PetscObjectComm((PetscObject)A));CHKERRQ(ierr);
910       *nrm = PetscSqrtReal(*nrm);
911       ierr = PetscLogFlops(2.0*mdn->A->cmap->n*mdn->A->rmap->n);CHKERRQ(ierr);
912     } else if (type == NORM_1) {
913       PetscReal *tmp,*tmp2;
914       ierr = PetscMalloc2(A->cmap->N,&tmp,A->cmap->N,&tmp2);CHKERRQ(ierr);
915       ierr = PetscMemzero(tmp,A->cmap->N*sizeof(PetscReal));CHKERRQ(ierr);
916       ierr = PetscMemzero(tmp2,A->cmap->N*sizeof(PetscReal));CHKERRQ(ierr);
917       *nrm = 0.0;
918       v    = mat->v;
919       for (j=0; j<mdn->A->cmap->n; j++) {
920         for (i=0; i<mdn->A->rmap->n; i++) {
921           tmp[j] += PetscAbsScalar(*v);  v++;
922         }
923       }
924       ierr = MPI_Allreduce(tmp,tmp2,A->cmap->N,MPIU_REAL,MPIU_SUM,PetscObjectComm((PetscObject)A));CHKERRQ(ierr);
925       for (j=0; j<A->cmap->N; j++) {
926         if (tmp2[j] > *nrm) *nrm = tmp2[j];
927       }
928       ierr = PetscFree2(tmp,tmp);CHKERRQ(ierr);
929       ierr = PetscLogFlops(A->cmap->n*A->rmap->n);CHKERRQ(ierr);
930     } else if (type == NORM_INFINITY) { /* max row norm */
931       PetscReal ntemp;
932       ierr = MatNorm(mdn->A,type,&ntemp);CHKERRQ(ierr);
933       ierr = MPI_Allreduce(&ntemp,nrm,1,MPIU_REAL,MPIU_MAX,PetscObjectComm((PetscObject)A));CHKERRQ(ierr);
934     } else SETERRQ(PetscObjectComm((PetscObject)A),PETSC_ERR_SUP,"No support for two norm");
935   }
936   PetscFunctionReturn(0);
937 }
938 
939 #undef __FUNCT__
940 #define __FUNCT__ "MatTranspose_MPIDense"
941 PetscErrorCode MatTranspose_MPIDense(Mat A,MatReuse reuse,Mat *matout)
942 {
943   Mat_MPIDense   *a    = (Mat_MPIDense*)A->data;
944   Mat_SeqDense   *Aloc = (Mat_SeqDense*)a->A->data;
945   Mat            B;
946   PetscInt       M = A->rmap->N,N = A->cmap->N,m,n,*rwork,rstart = A->rmap->rstart;
947   PetscErrorCode ierr;
948   PetscInt       j,i;
949   PetscScalar    *v;
950 
951   PetscFunctionBegin;
952   if (reuse == MAT_REUSE_MATRIX && A == *matout && M != N) SETERRQ(PetscObjectComm((PetscObject)A),PETSC_ERR_SUP,"Supports square matrix only in-place");
953   if (reuse == MAT_INITIAL_MATRIX || A == *matout) {
954     ierr = MatCreate(PetscObjectComm((PetscObject)A),&B);CHKERRQ(ierr);
955     ierr = MatSetSizes(B,A->cmap->n,A->rmap->n,N,M);CHKERRQ(ierr);
956     ierr = MatSetType(B,((PetscObject)A)->type_name);CHKERRQ(ierr);
957     ierr = MatMPIDenseSetPreallocation(B,NULL);CHKERRQ(ierr);
958   } else {
959     B = *matout;
960   }
961 
962   m    = a->A->rmap->n; n = a->A->cmap->n; v = Aloc->v;
963   ierr = PetscMalloc1(m,&rwork);CHKERRQ(ierr);
964   for (i=0; i<m; i++) rwork[i] = rstart + i;
965   for (j=0; j<n; j++) {
966     ierr = MatSetValues(B,1,&j,m,rwork,v,INSERT_VALUES);CHKERRQ(ierr);
967     v   += m;
968   }
969   ierr = PetscFree(rwork);CHKERRQ(ierr);
970   ierr = MatAssemblyBegin(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
971   ierr = MatAssemblyEnd(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
972   if (reuse == MAT_INITIAL_MATRIX || *matout != A) {
973     *matout = B;
974   } else {
975     ierr = MatHeaderMerge(A,B);CHKERRQ(ierr);
976   }
977   PetscFunctionReturn(0);
978 }
979 
980 
981 static PetscErrorCode MatDuplicate_MPIDense(Mat,MatDuplicateOption,Mat*);
982 extern PetscErrorCode MatScale_MPIDense(Mat,PetscScalar);
983 
984 #undef __FUNCT__
985 #define __FUNCT__ "MatSetUp_MPIDense"
986 PetscErrorCode MatSetUp_MPIDense(Mat A)
987 {
988   PetscErrorCode ierr;
989 
990   PetscFunctionBegin;
991   ierr =  MatMPIDenseSetPreallocation(A,0);CHKERRQ(ierr);
992   PetscFunctionReturn(0);
993 }
994 
995 #undef __FUNCT__
996 #define __FUNCT__ "MatAXPY_MPIDense"
997 PetscErrorCode MatAXPY_MPIDense(Mat Y,PetscScalar alpha,Mat X,MatStructure str)
998 {
999   PetscErrorCode ierr;
1000   Mat_MPIDense   *A = (Mat_MPIDense*)Y->data, *B = (Mat_MPIDense*)X->data;
1001 
1002   PetscFunctionBegin;
1003   ierr = MatAXPY(A->A,alpha,B->A,str);CHKERRQ(ierr);
1004   ierr = PetscObjectStateIncrease((PetscObject)Y);CHKERRQ(ierr);
1005   PetscFunctionReturn(0);
1006 }
1007 
1008 #undef __FUNCT__
1009 #define __FUNCT__ "MatConjugate_MPIDense"
1010 PetscErrorCode  MatConjugate_MPIDense(Mat mat)
1011 {
1012   Mat_MPIDense   *a = (Mat_MPIDense*)mat->data;
1013   PetscErrorCode ierr;
1014 
1015   PetscFunctionBegin;
1016   ierr = MatConjugate(a->A);CHKERRQ(ierr);
1017   PetscFunctionReturn(0);
1018 }
1019 
1020 #undef __FUNCT__
1021 #define __FUNCT__ "MatRealPart_MPIDense"
1022 PetscErrorCode MatRealPart_MPIDense(Mat A)
1023 {
1024   Mat_MPIDense   *a = (Mat_MPIDense*)A->data;
1025   PetscErrorCode ierr;
1026 
1027   PetscFunctionBegin;
1028   ierr = MatRealPart(a->A);CHKERRQ(ierr);
1029   PetscFunctionReturn(0);
1030 }
1031 
1032 #undef __FUNCT__
1033 #define __FUNCT__ "MatImaginaryPart_MPIDense"
1034 PetscErrorCode MatImaginaryPart_MPIDense(Mat A)
1035 {
1036   Mat_MPIDense   *a = (Mat_MPIDense*)A->data;
1037   PetscErrorCode ierr;
1038 
1039   PetscFunctionBegin;
1040   ierr = MatImaginaryPart(a->A);CHKERRQ(ierr);
1041   PetscFunctionReturn(0);
1042 }
1043 
1044 extern PetscErrorCode MatGetColumnNorms_SeqDense(Mat,NormType,PetscReal*);
1045 #undef __FUNCT__
1046 #define __FUNCT__ "MatGetColumnNorms_MPIDense"
1047 PetscErrorCode MatGetColumnNorms_MPIDense(Mat A,NormType type,PetscReal *norms)
1048 {
1049   PetscErrorCode ierr;
1050   PetscInt       i,n;
1051   Mat_MPIDense   *a = (Mat_MPIDense*) A->data;
1052   PetscReal      *work;
1053 
1054   PetscFunctionBegin;
1055   ierr = MatGetSize(A,NULL,&n);CHKERRQ(ierr);
1056   ierr = PetscMalloc1(n,&work);CHKERRQ(ierr);
1057   ierr = MatGetColumnNorms_SeqDense(a->A,type,work);CHKERRQ(ierr);
1058   if (type == NORM_2) {
1059     for (i=0; i<n; i++) work[i] *= work[i];
1060   }
1061   if (type == NORM_INFINITY) {
1062     ierr = MPI_Allreduce(work,norms,n,MPIU_REAL,MPIU_MAX,A->hdr.comm);CHKERRQ(ierr);
1063   } else {
1064     ierr = MPI_Allreduce(work,norms,n,MPIU_REAL,MPIU_SUM,A->hdr.comm);CHKERRQ(ierr);
1065   }
1066   ierr = PetscFree(work);CHKERRQ(ierr);
1067   if (type == NORM_2) {
1068     for (i=0; i<n; i++) norms[i] = PetscSqrtReal(norms[i]);
1069   }
1070   PetscFunctionReturn(0);
1071 }
1072 
1073 #undef __FUNCT__
1074 #define __FUNCT__ "MatSetRandom_MPIDense"
1075 static PetscErrorCode  MatSetRandom_MPIDense(Mat x,PetscRandom rctx)
1076 {
1077   Mat_MPIDense   *d = (Mat_MPIDense*)x->data;
1078   PetscErrorCode ierr;
1079   PetscScalar    *a;
1080   PetscInt       m,n,i;
1081 
1082   PetscFunctionBegin;
1083   ierr = MatGetSize(d->A,&m,&n);CHKERRQ(ierr);
1084   ierr = MatDenseGetArray(d->A,&a);CHKERRQ(ierr);
1085   for (i=0; i<m*n; i++) {
1086     ierr = PetscRandomGetValue(rctx,a+i);CHKERRQ(ierr);
1087   }
1088   ierr = MatDenseRestoreArray(d->A,&a);CHKERRQ(ierr);
1089   PetscFunctionReturn(0);
1090 }
1091 
1092 extern PetscErrorCode MatMatMultNumeric_MPIDense(Mat A,Mat,Mat);
1093 
1094 /* -------------------------------------------------------------------*/
1095 static struct _MatOps MatOps_Values = { MatSetValues_MPIDense,
1096                                         MatGetRow_MPIDense,
1097                                         MatRestoreRow_MPIDense,
1098                                         MatMult_MPIDense,
1099                                 /*  4*/ MatMultAdd_MPIDense,
1100                                         MatMultTranspose_MPIDense,
1101                                         MatMultTransposeAdd_MPIDense,
1102                                         0,
1103                                         0,
1104                                         0,
1105                                 /* 10*/ 0,
1106                                         0,
1107                                         0,
1108                                         0,
1109                                         MatTranspose_MPIDense,
1110                                 /* 15*/ MatGetInfo_MPIDense,
1111                                         MatEqual_MPIDense,
1112                                         MatGetDiagonal_MPIDense,
1113                                         MatDiagonalScale_MPIDense,
1114                                         MatNorm_MPIDense,
1115                                 /* 20*/ MatAssemblyBegin_MPIDense,
1116                                         MatAssemblyEnd_MPIDense,
1117                                         MatSetOption_MPIDense,
1118                                         MatZeroEntries_MPIDense,
1119                                 /* 24*/ MatZeroRows_MPIDense,
1120                                         0,
1121                                         0,
1122                                         0,
1123                                         0,
1124                                 /* 29*/ MatSetUp_MPIDense,
1125                                         0,
1126                                         0,
1127                                         0,
1128                                         0,
1129                                 /* 34*/ MatDuplicate_MPIDense,
1130                                         0,
1131                                         0,
1132                                         0,
1133                                         0,
1134                                 /* 39*/ MatAXPY_MPIDense,
1135                                         MatGetSubMatrices_MPIDense,
1136                                         0,
1137                                         MatGetValues_MPIDense,
1138                                         0,
1139                                 /* 44*/ 0,
1140                                         MatScale_MPIDense,
1141                                         MatShift_Basic,
1142                                         0,
1143                                         0,
1144                                 /* 49*/ MatSetRandom_MPIDense,
1145                                         0,
1146                                         0,
1147                                         0,
1148                                         0,
1149                                 /* 54*/ 0,
1150                                         0,
1151                                         0,
1152                                         0,
1153                                         0,
1154                                 /* 59*/ MatGetSubMatrix_MPIDense,
1155                                         MatDestroy_MPIDense,
1156                                         MatView_MPIDense,
1157                                         0,
1158                                         0,
1159                                 /* 64*/ 0,
1160                                         0,
1161                                         0,
1162                                         0,
1163                                         0,
1164                                 /* 69*/ 0,
1165                                         0,
1166                                         0,
1167                                         0,
1168                                         0,
1169                                 /* 74*/ 0,
1170                                         0,
1171                                         0,
1172                                         0,
1173                                         0,
1174                                 /* 79*/ 0,
1175                                         0,
1176                                         0,
1177                                         0,
1178                                 /* 83*/ MatLoad_MPIDense,
1179                                         0,
1180                                         0,
1181                                         0,
1182                                         0,
1183                                         0,
1184                                 /* 89*/
1185                                         0,
1186                                         0,
1187                                         MatMatMultNumeric_MPIDense,
1188                                         0,
1189                                         0,
1190                                 /* 94*/ 0,
1191                                         0,
1192                                         0,
1193                                         0,
1194                                         0,
1195                                 /* 99*/ 0,
1196                                         0,
1197                                         0,
1198                                         MatConjugate_MPIDense,
1199                                         0,
1200                                 /*104*/ 0,
1201                                         MatRealPart_MPIDense,
1202                                         MatImaginaryPart_MPIDense,
1203                                         0,
1204                                         0,
1205                                 /*109*/ 0,
1206                                         0,
1207                                         0,
1208                                         0,
1209                                         0,
1210                                 /*114*/ 0,
1211                                         0,
1212                                         0,
1213                                         0,
1214                                         0,
1215                                 /*119*/ 0,
1216                                         0,
1217                                         0,
1218                                         0,
1219                                         0,
1220                                 /*124*/ 0,
1221                                         MatGetColumnNorms_MPIDense,
1222                                         0,
1223                                         0,
1224                                         0,
1225                                 /*129*/ 0,
1226                                         0,
1227                                         0,
1228                                         0,
1229                                         0,
1230                                 /*134*/ 0,
1231                                         0,
1232                                         0,
1233                                         0,
1234                                         0,
1235                                 /*139*/ 0,
1236                                         0,
1237                                         0
1238 };
1239 
1240 #undef __FUNCT__
1241 #define __FUNCT__ "MatMPIDenseSetPreallocation_MPIDense"
1242 PetscErrorCode  MatMPIDenseSetPreallocation_MPIDense(Mat mat,PetscScalar *data)
1243 {
1244   Mat_MPIDense   *a;
1245   PetscErrorCode ierr;
1246 
1247   PetscFunctionBegin;
1248   mat->preallocated = PETSC_TRUE;
1249   /* Note:  For now, when data is specified above, this assumes the user correctly
1250    allocates the local dense storage space.  We should add error checking. */
1251 
1252   a       = (Mat_MPIDense*)mat->data;
1253   ierr    = PetscLayoutSetUp(mat->rmap);CHKERRQ(ierr);
1254   ierr    = PetscLayoutSetUp(mat->cmap);CHKERRQ(ierr);
1255   a->nvec = mat->cmap->n;
1256 
1257   ierr = MatCreate(PETSC_COMM_SELF,&a->A);CHKERRQ(ierr);
1258   ierr = MatSetSizes(a->A,mat->rmap->n,mat->cmap->N,mat->rmap->n,mat->cmap->N);CHKERRQ(ierr);
1259   ierr = MatSetType(a->A,MATSEQDENSE);CHKERRQ(ierr);
1260   ierr = MatSeqDenseSetPreallocation(a->A,data);CHKERRQ(ierr);
1261   ierr = PetscLogObjectParent((PetscObject)mat,(PetscObject)a->A);CHKERRQ(ierr);
1262   PetscFunctionReturn(0);
1263 }
1264 
1265 #if defined(PETSC_HAVE_ELEMENTAL)
1266 #undef __FUNCT__
1267 #define __FUNCT__ "MatConvert_MPIDense_Elemental"
1268 PETSC_EXTERN PetscErrorCode MatConvert_MPIDense_Elemental(Mat A, MatType newtype,MatReuse reuse,Mat *newmat)
1269 {
1270   Mat            mat_elemental;
1271   PetscErrorCode ierr;
1272   PetscScalar    *array,*v_rowwise;
1273   PetscInt       m=A->rmap->n,N=A->cmap->N,rstart=A->rmap->rstart,i,j,k,*rows,*cols;
1274 
1275   PetscFunctionBegin;
1276   ierr = PetscMalloc3(m*N,&v_rowwise,m,&rows,N,&cols);CHKERRQ(ierr);
1277   ierr = MatDenseGetArray(A,&array);CHKERRQ(ierr);
1278   /* convert column-wise array into row-wise v_rowwise, see MatSetValues_Elemental() */
1279   k = 0;
1280   for (j=0; j<N; j++) {
1281     cols[j] = j;
1282     for (i=0; i<m; i++) {
1283       v_rowwise[i*N+j] = array[k++];
1284     }
1285   }
1286   for (i=0; i<m; i++) {
1287     rows[i] = rstart + i;
1288   }
1289   ierr = MatDenseRestoreArray(A,&array);CHKERRQ(ierr);
1290 
1291   ierr = MatCreate(PetscObjectComm((PetscObject)A), &mat_elemental);CHKERRQ(ierr);
1292   ierr = MatSetSizes(mat_elemental,PETSC_DECIDE,PETSC_DECIDE,A->rmap->N,A->cmap->N);CHKERRQ(ierr);
1293   ierr = MatSetType(mat_elemental,MATELEMENTAL);CHKERRQ(ierr);
1294   ierr = MatSetUp(mat_elemental);CHKERRQ(ierr);
1295 
1296   /* PETSc-Elemental interaface uses axpy for setting off-processor entries, only ADD_VALUES is allowed */
1297   ierr = MatSetValues(mat_elemental,m,rows,N,cols,v_rowwise,ADD_VALUES);CHKERRQ(ierr);
1298   ierr = MatAssemblyBegin(mat_elemental, MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
1299   ierr = MatAssemblyEnd(mat_elemental, MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
1300   ierr = PetscFree3(v_rowwise,rows,cols);CHKERRQ(ierr);
1301 
1302   if (reuse == MAT_REUSE_MATRIX) {
1303     ierr = MatHeaderReplace(A,mat_elemental);CHKERRQ(ierr);
1304   } else {
1305     *newmat = mat_elemental;
1306   }
1307   PetscFunctionReturn(0);
1308 }
1309 #endif
1310 
1311 #undef __FUNCT__
1312 #define __FUNCT__ "MatCreate_MPIDense"
1313 PETSC_EXTERN PetscErrorCode MatCreate_MPIDense(Mat mat)
1314 {
1315   Mat_MPIDense   *a;
1316   PetscErrorCode ierr;
1317 
1318   PetscFunctionBegin;
1319   ierr      = PetscNewLog(mat,&a);CHKERRQ(ierr);
1320   mat->data = (void*)a;
1321   ierr      = PetscMemcpy(mat->ops,&MatOps_Values,sizeof(struct _MatOps));CHKERRQ(ierr);
1322 
1323   mat->insertmode = NOT_SET_VALUES;
1324   ierr            = MPI_Comm_rank(PetscObjectComm((PetscObject)mat),&a->rank);CHKERRQ(ierr);
1325   ierr            = MPI_Comm_size(PetscObjectComm((PetscObject)mat),&a->size);CHKERRQ(ierr);
1326 
1327   /* build cache for off array entries formed */
1328   a->donotstash = PETSC_FALSE;
1329 
1330   ierr = MatStashCreate_Private(PetscObjectComm((PetscObject)mat),1,&mat->stash);CHKERRQ(ierr);
1331 
1332   /* stuff used for matrix vector multiply */
1333   a->lvec        = 0;
1334   a->Mvctx       = 0;
1335   a->roworiented = PETSC_TRUE;
1336 
1337   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatDenseGetArray_C",MatDenseGetArray_MPIDense);CHKERRQ(ierr);
1338   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatDenseRestoreArray_C",MatDenseRestoreArray_MPIDense);CHKERRQ(ierr);
1339 #if defined(PETSC_HAVE_ELEMENTAL)
1340   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatConvert_mpidense_elemental_C",MatConvert_MPIDense_Elemental);CHKERRQ(ierr);
1341 #endif
1342   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatGetDiagonalBlock_C",MatGetDiagonalBlock_MPIDense);CHKERRQ(ierr);
1343   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatMPIDenseSetPreallocation_C",MatMPIDenseSetPreallocation_MPIDense);CHKERRQ(ierr);
1344   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatMatMult_mpiaij_mpidense_C",MatMatMult_MPIAIJ_MPIDense);CHKERRQ(ierr);
1345   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatMatMultSymbolic_mpiaij_mpidense_C",MatMatMultSymbolic_MPIAIJ_MPIDense);CHKERRQ(ierr);
1346   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatMatMultNumeric_mpiaij_mpidense_C",MatMatMultNumeric_MPIAIJ_MPIDense);CHKERRQ(ierr);
1347 
1348   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatTransposeMatMult_mpiaij_mpidense_C",MatTransposeMatMult_MPIAIJ_MPIDense);CHKERRQ(ierr);
1349   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatTransposeMatMultSymbolic_mpiaij_mpidense_C",MatTransposeMatMultSymbolic_MPIAIJ_MPIDense);CHKERRQ(ierr);
1350   ierr = PetscObjectComposeFunction((PetscObject)mat,"MatTransposeMatMultNumeric_mpiaij_mpidense_C",MatTransposeMatMultNumeric_MPIAIJ_MPIDense);CHKERRQ(ierr);
1351   ierr = PetscObjectChangeTypeName((PetscObject)mat,MATMPIDENSE);CHKERRQ(ierr);
1352   PetscFunctionReturn(0);
1353 }
1354 
1355 /*MC
1356    MATDENSE - MATDENSE = "dense" - A matrix type to be used for dense matrices.
1357 
1358    This matrix type is identical to MATSEQDENSE when constructed with a single process communicator,
1359    and MATMPIDENSE otherwise.
1360 
1361    Options Database Keys:
1362 . -mat_type dense - sets the matrix type to "dense" during a call to MatSetFromOptions()
1363 
1364   Level: beginner
1365 
1366 
1367 .seealso: MatCreateMPIDense,MATSEQDENSE,MATMPIDENSE
1368 M*/
1369 
1370 #undef __FUNCT__
1371 #define __FUNCT__ "MatMPIDenseSetPreallocation"
1372 /*@C
1373    MatMPIDenseSetPreallocation - Sets the array used to store the matrix entries
1374 
1375    Not collective
1376 
1377    Input Parameters:
1378 .  B - the matrix
1379 -  data - optional location of matrix data.  Set data=NULL for PETSc
1380    to control all matrix memory allocation.
1381 
1382    Notes:
1383    The dense format is fully compatible with standard Fortran 77
1384    storage by columns.
1385 
1386    The data input variable is intended primarily for Fortran programmers
1387    who wish to allocate their own matrix memory space.  Most users should
1388    set data=NULL.
1389 
1390    Level: intermediate
1391 
1392 .keywords: matrix,dense, parallel
1393 
1394 .seealso: MatCreate(), MatCreateSeqDense(), MatSetValues()
1395 @*/
1396 PetscErrorCode  MatMPIDenseSetPreallocation(Mat B,PetscScalar *data)
1397 {
1398   PetscErrorCode ierr;
1399 
1400   PetscFunctionBegin;
1401   ierr = PetscTryMethod(B,"MatMPIDenseSetPreallocation_C",(Mat,PetscScalar*),(B,data));CHKERRQ(ierr);
1402   PetscFunctionReturn(0);
1403 }
1404 
1405 #undef __FUNCT__
1406 #define __FUNCT__ "MatCreateDense"
1407 /*@C
1408    MatCreateDense - Creates a parallel matrix in dense format.
1409 
1410    Collective on MPI_Comm
1411 
1412    Input Parameters:
1413 +  comm - MPI communicator
1414 .  m - number of local rows (or PETSC_DECIDE to have calculated if M is given)
1415 .  n - number of local columns (or PETSC_DECIDE to have calculated if N is given)
1416 .  M - number of global rows (or PETSC_DECIDE to have calculated if m is given)
1417 .  N - number of global columns (or PETSC_DECIDE to have calculated if n is given)
1418 -  data - optional location of matrix data.  Set data=NULL (PETSC_NULL_SCALAR for Fortran users) for PETSc
1419    to control all matrix memory allocation.
1420 
1421    Output Parameter:
1422 .  A - the matrix
1423 
1424    Notes:
1425    The dense format is fully compatible with standard Fortran 77
1426    storage by columns.
1427 
1428    The data input variable is intended primarily for Fortran programmers
1429    who wish to allocate their own matrix memory space.  Most users should
1430    set data=NULL (PETSC_NULL_SCALAR for Fortran users).
1431 
1432    The user MUST specify either the local or global matrix dimensions
1433    (possibly both).
1434 
1435    Level: intermediate
1436 
1437 .keywords: matrix,dense, parallel
1438 
1439 .seealso: MatCreate(), MatCreateSeqDense(), MatSetValues()
1440 @*/
1441 PetscErrorCode  MatCreateDense(MPI_Comm comm,PetscInt m,PetscInt n,PetscInt M,PetscInt N,PetscScalar *data,Mat *A)
1442 {
1443   PetscErrorCode ierr;
1444   PetscMPIInt    size;
1445 
1446   PetscFunctionBegin;
1447   ierr = MatCreate(comm,A);CHKERRQ(ierr);
1448   ierr = MatSetSizes(*A,m,n,M,N);CHKERRQ(ierr);
1449   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
1450   if (size > 1) {
1451     ierr = MatSetType(*A,MATMPIDENSE);CHKERRQ(ierr);
1452     ierr = MatMPIDenseSetPreallocation(*A,data);CHKERRQ(ierr);
1453     if (data) {  /* user provided data array, so no need to assemble */
1454       ierr = MatSetUpMultiply_MPIDense(*A);CHKERRQ(ierr);
1455       (*A)->assembled = PETSC_TRUE;
1456     }
1457   } else {
1458     ierr = MatSetType(*A,MATSEQDENSE);CHKERRQ(ierr);
1459     ierr = MatSeqDenseSetPreallocation(*A,data);CHKERRQ(ierr);
1460   }
1461   PetscFunctionReturn(0);
1462 }
1463 
1464 #undef __FUNCT__
1465 #define __FUNCT__ "MatDuplicate_MPIDense"
1466 static PetscErrorCode MatDuplicate_MPIDense(Mat A,MatDuplicateOption cpvalues,Mat *newmat)
1467 {
1468   Mat            mat;
1469   Mat_MPIDense   *a,*oldmat = (Mat_MPIDense*)A->data;
1470   PetscErrorCode ierr;
1471 
1472   PetscFunctionBegin;
1473   *newmat = 0;
1474   ierr    = MatCreate(PetscObjectComm((PetscObject)A),&mat);CHKERRQ(ierr);
1475   ierr    = MatSetSizes(mat,A->rmap->n,A->cmap->n,A->rmap->N,A->cmap->N);CHKERRQ(ierr);
1476   ierr    = MatSetType(mat,((PetscObject)A)->type_name);CHKERRQ(ierr);
1477   a       = (Mat_MPIDense*)mat->data;
1478   ierr    = PetscMemcpy(mat->ops,A->ops,sizeof(struct _MatOps));CHKERRQ(ierr);
1479 
1480   mat->factortype   = A->factortype;
1481   mat->assembled    = PETSC_TRUE;
1482   mat->preallocated = PETSC_TRUE;
1483 
1484   a->size         = oldmat->size;
1485   a->rank         = oldmat->rank;
1486   mat->insertmode = NOT_SET_VALUES;
1487   a->nvec         = oldmat->nvec;
1488   a->donotstash   = oldmat->donotstash;
1489 
1490   ierr = PetscLayoutReference(A->rmap,&mat->rmap);CHKERRQ(ierr);
1491   ierr = PetscLayoutReference(A->cmap,&mat->cmap);CHKERRQ(ierr);
1492 
1493   ierr = MatSetUpMultiply_MPIDense(mat);CHKERRQ(ierr);
1494   ierr = MatDuplicate(oldmat->A,cpvalues,&a->A);CHKERRQ(ierr);
1495   ierr = PetscLogObjectParent((PetscObject)mat,(PetscObject)a->A);CHKERRQ(ierr);
1496 
1497   *newmat = mat;
1498   PetscFunctionReturn(0);
1499 }
1500 
1501 #undef __FUNCT__
1502 #define __FUNCT__ "MatLoad_MPIDense_DenseInFile"
1503 PetscErrorCode MatLoad_MPIDense_DenseInFile(MPI_Comm comm,PetscInt fd,PetscInt M,PetscInt N,Mat newmat)
1504 {
1505   PetscErrorCode ierr;
1506   PetscMPIInt    rank,size;
1507   const PetscInt *rowners;
1508   PetscInt       i,m,n,nz,j,mMax;
1509   PetscScalar    *array,*vals,*vals_ptr;
1510   Mat_MPIDense   *a = (Mat_MPIDense*)newmat->data;
1511 
1512   PetscFunctionBegin;
1513   ierr = MPI_Comm_rank(comm,&rank);CHKERRQ(ierr);
1514   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
1515 
1516   /* determine ownership of rows and columns */
1517   m = (newmat->rmap->n < 0) ? PETSC_DECIDE : newmat->rmap->n;
1518   n = (newmat->cmap->n < 0) ? PETSC_DECIDE : newmat->cmap->n;
1519 
1520   ierr = MatSetSizes(newmat,m,n,M,N);CHKERRQ(ierr);
1521   if (!a->A || !((Mat_SeqDense*)(a->A->data))->user_alloc) {
1522     ierr = MatMPIDenseSetPreallocation(newmat,NULL);CHKERRQ(ierr);
1523   }
1524   ierr = MatDenseGetArray(newmat,&array);CHKERRQ(ierr);
1525   ierr = MatGetLocalSize(newmat,&m,NULL);CHKERRQ(ierr);
1526   ierr = MatGetOwnershipRanges(newmat,&rowners);CHKERRQ(ierr);
1527   ierr = MPI_Reduce(&m,&mMax,1,MPIU_INT,MPI_MAX,0,comm);CHKERRQ(ierr);
1528   if (!rank) {
1529     ierr = PetscMalloc1(mMax*N,&vals);CHKERRQ(ierr);
1530 
1531     /* read in my part of the matrix numerical values  */
1532     ierr = PetscBinaryRead(fd,vals,m*N,PETSC_SCALAR);CHKERRQ(ierr);
1533 
1534     /* insert into matrix-by row (this is why cannot directly read into array */
1535     vals_ptr = vals;
1536     for (i=0; i<m; i++) {
1537       for (j=0; j<N; j++) {
1538         array[i + j*m] = *vals_ptr++;
1539       }
1540     }
1541 
1542     /* read in other processors and ship out */
1543     for (i=1; i<size; i++) {
1544       nz   = (rowners[i+1] - rowners[i])*N;
1545       ierr = PetscBinaryRead(fd,vals,nz,PETSC_SCALAR);CHKERRQ(ierr);
1546       ierr = MPIULong_Send(vals,nz,MPIU_SCALAR,i,((PetscObject)(newmat))->tag,comm);CHKERRQ(ierr);
1547     }
1548   } else {
1549     /* receive numeric values */
1550     ierr = PetscMalloc1(m*N,&vals);CHKERRQ(ierr);
1551 
1552     /* receive message of values*/
1553     ierr = MPIULong_Recv(vals,m*N,MPIU_SCALAR,0,((PetscObject)(newmat))->tag,comm);CHKERRQ(ierr);
1554 
1555     /* insert into matrix-by row (this is why cannot directly read into array */
1556     vals_ptr = vals;
1557     for (i=0; i<m; i++) {
1558       for (j=0; j<N; j++) {
1559         array[i + j*m] = *vals_ptr++;
1560       }
1561     }
1562   }
1563   ierr = MatDenseRestoreArray(newmat,&array);CHKERRQ(ierr);
1564   ierr = PetscFree(vals);CHKERRQ(ierr);
1565   ierr = MatAssemblyBegin(newmat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
1566   ierr = MatAssemblyEnd(newmat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
1567   PetscFunctionReturn(0);
1568 }
1569 
1570 #undef __FUNCT__
1571 #define __FUNCT__ "MatLoad_MPIDense"
1572 PetscErrorCode MatLoad_MPIDense(Mat newmat,PetscViewer viewer)
1573 {
1574   Mat_MPIDense   *a;
1575   PetscScalar    *vals,*svals;
1576   MPI_Comm       comm;
1577   MPI_Status     status;
1578   PetscMPIInt    rank,size,tag = ((PetscObject)viewer)->tag,*rowners,*sndcounts,m,n,maxnz;
1579   PetscInt       header[4],*rowlengths = 0,M,N,*cols;
1580   PetscInt       *ourlens,*procsnz = 0,jj,*mycols,*smycols;
1581   PetscInt       i,nz,j,rstart,rend;
1582   int            fd;
1583   PetscErrorCode ierr;
1584 
1585   PetscFunctionBegin;
1586   /* force binary viewer to load .info file if it has not yet done so */
1587   ierr = PetscViewerSetUp(viewer);CHKERRQ(ierr);
1588   ierr = PetscObjectGetComm((PetscObject)viewer,&comm);CHKERRQ(ierr);
1589   ierr = MPI_Comm_size(comm,&size);CHKERRQ(ierr);
1590   ierr = MPI_Comm_rank(comm,&rank);CHKERRQ(ierr);
1591   ierr = PetscViewerBinaryGetDescriptor(viewer,&fd);CHKERRQ(ierr);
1592   if (!rank) {
1593     ierr = PetscBinaryRead(fd,(char*)header,4,PETSC_INT);CHKERRQ(ierr);
1594     if (header[0] != MAT_FILE_CLASSID) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_FILE_UNEXPECTED,"not matrix object");
1595   }
1596   ierr = MPI_Bcast(header+1,3,MPIU_INT,0,comm);CHKERRQ(ierr);
1597   M    = header[1]; N = header[2]; nz = header[3];
1598 
1599   /* If global rows/cols are set to PETSC_DECIDE, set it to the sizes given in the file */
1600   if (newmat->rmap->N < 0) newmat->rmap->N = M;
1601   if (newmat->cmap->N < 0) newmat->cmap->N = N;
1602 
1603   if (newmat->rmap->N != M) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_FILE_UNEXPECTED, "Inconsistent # of rows:Matrix in file has (%D) and input matrix has (%D)",M,newmat->rmap->N);
1604   if (newmat->cmap->N != N) SETERRQ2(PETSC_COMM_SELF,PETSC_ERR_FILE_UNEXPECTED, "Inconsistent # of cols:Matrix in file has (%D) and input matrix has (%D)",N,newmat->cmap->N);
1605 
1606   /*
1607        Handle case where matrix is stored on disk as a dense matrix
1608   */
1609   if (nz == MATRIX_BINARY_FORMAT_DENSE) {
1610     ierr = MatLoad_MPIDense_DenseInFile(comm,fd,M,N,newmat);CHKERRQ(ierr);
1611     PetscFunctionReturn(0);
1612   }
1613 
1614   /* determine ownership of all rows */
1615   if (newmat->rmap->n < 0) {
1616     ierr = PetscMPIIntCast(M/size + ((M % size) > rank),&m);CHKERRQ(ierr);
1617   } else {
1618     ierr = PetscMPIIntCast(newmat->rmap->n,&m);CHKERRQ(ierr);
1619   }
1620   if (newmat->cmap->n < 0) {
1621     n = PETSC_DECIDE;
1622   } else {
1623     ierr = PetscMPIIntCast(newmat->cmap->n,&n);CHKERRQ(ierr);
1624   }
1625 
1626   ierr       = PetscMalloc1(size+2,&rowners);CHKERRQ(ierr);
1627   ierr       = MPI_Allgather(&m,1,MPI_INT,rowners+1,1,MPI_INT,comm);CHKERRQ(ierr);
1628   rowners[0] = 0;
1629   for (i=2; i<=size; i++) {
1630     rowners[i] += rowners[i-1];
1631   }
1632   rstart = rowners[rank];
1633   rend   = rowners[rank+1];
1634 
1635   /* distribute row lengths to all processors */
1636   ierr = PetscMalloc1(rend-rstart,&ourlens);CHKERRQ(ierr);
1637   if (!rank) {
1638     ierr = PetscMalloc1(M,&rowlengths);CHKERRQ(ierr);
1639     ierr = PetscBinaryRead(fd,rowlengths,M,PETSC_INT);CHKERRQ(ierr);
1640     ierr = PetscMalloc1(size,&sndcounts);CHKERRQ(ierr);
1641     for (i=0; i<size; i++) sndcounts[i] = rowners[i+1] - rowners[i];
1642     ierr = MPI_Scatterv(rowlengths,sndcounts,rowners,MPIU_INT,ourlens,rend-rstart,MPIU_INT,0,comm);CHKERRQ(ierr);
1643     ierr = PetscFree(sndcounts);CHKERRQ(ierr);
1644   } else {
1645     ierr = MPI_Scatterv(0,0,0,MPIU_INT,ourlens,rend-rstart,MPIU_INT,0,comm);CHKERRQ(ierr);
1646   }
1647 
1648   if (!rank) {
1649     /* calculate the number of nonzeros on each processor */
1650     ierr = PetscMalloc1(size,&procsnz);CHKERRQ(ierr);
1651     ierr = PetscMemzero(procsnz,size*sizeof(PetscInt));CHKERRQ(ierr);
1652     for (i=0; i<size; i++) {
1653       for (j=rowners[i]; j< rowners[i+1]; j++) {
1654         procsnz[i] += rowlengths[j];
1655       }
1656     }
1657     ierr = PetscFree(rowlengths);CHKERRQ(ierr);
1658 
1659     /* determine max buffer needed and allocate it */
1660     maxnz = 0;
1661     for (i=0; i<size; i++) {
1662       maxnz = PetscMax(maxnz,procsnz[i]);
1663     }
1664     ierr = PetscMalloc1(maxnz,&cols);CHKERRQ(ierr);
1665 
1666     /* read in my part of the matrix column indices  */
1667     nz   = procsnz[0];
1668     ierr = PetscMalloc1(nz,&mycols);CHKERRQ(ierr);
1669     ierr = PetscBinaryRead(fd,mycols,nz,PETSC_INT);CHKERRQ(ierr);
1670 
1671     /* read in every one elses and ship off */
1672     for (i=1; i<size; i++) {
1673       nz   = procsnz[i];
1674       ierr = PetscBinaryRead(fd,cols,nz,PETSC_INT);CHKERRQ(ierr);
1675       ierr = MPI_Send(cols,nz,MPIU_INT,i,tag,comm);CHKERRQ(ierr);
1676     }
1677     ierr = PetscFree(cols);CHKERRQ(ierr);
1678   } else {
1679     /* determine buffer space needed for message */
1680     nz = 0;
1681     for (i=0; i<m; i++) {
1682       nz += ourlens[i];
1683     }
1684     ierr = PetscMalloc1(nz+1,&mycols);CHKERRQ(ierr);
1685 
1686     /* receive message of column indices*/
1687     ierr = MPI_Recv(mycols,nz,MPIU_INT,0,tag,comm,&status);CHKERRQ(ierr);
1688     ierr = MPI_Get_count(&status,MPIU_INT,&maxnz);CHKERRQ(ierr);
1689     if (maxnz != nz) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_FILE_UNEXPECTED,"something is wrong with file");
1690   }
1691 
1692   ierr = MatSetSizes(newmat,m,n,M,N);CHKERRQ(ierr);
1693   a = (Mat_MPIDense*)newmat->data;
1694   if (!a->A || !((Mat_SeqDense*)(a->A->data))->user_alloc) {
1695     ierr = MatMPIDenseSetPreallocation(newmat,NULL);CHKERRQ(ierr);
1696   }
1697 
1698   if (!rank) {
1699     ierr = PetscMalloc1(maxnz,&vals);CHKERRQ(ierr);
1700 
1701     /* read in my part of the matrix numerical values  */
1702     nz   = procsnz[0];
1703     ierr = PetscBinaryRead(fd,vals,nz,PETSC_SCALAR);CHKERRQ(ierr);
1704 
1705     /* insert into matrix */
1706     jj      = rstart;
1707     smycols = mycols;
1708     svals   = vals;
1709     for (i=0; i<m; i++) {
1710       ierr     = MatSetValues(newmat,1,&jj,ourlens[i],smycols,svals,INSERT_VALUES);CHKERRQ(ierr);
1711       smycols += ourlens[i];
1712       svals   += ourlens[i];
1713       jj++;
1714     }
1715 
1716     /* read in other processors and ship out */
1717     for (i=1; i<size; i++) {
1718       nz   = procsnz[i];
1719       ierr = PetscBinaryRead(fd,vals,nz,PETSC_SCALAR);CHKERRQ(ierr);
1720       ierr = MPI_Send(vals,nz,MPIU_SCALAR,i,((PetscObject)newmat)->tag,comm);CHKERRQ(ierr);
1721     }
1722     ierr = PetscFree(procsnz);CHKERRQ(ierr);
1723   } else {
1724     /* receive numeric values */
1725     ierr = PetscMalloc1(nz+1,&vals);CHKERRQ(ierr);
1726 
1727     /* receive message of values*/
1728     ierr = MPI_Recv(vals,nz,MPIU_SCALAR,0,((PetscObject)newmat)->tag,comm,&status);CHKERRQ(ierr);
1729     ierr = MPI_Get_count(&status,MPIU_SCALAR,&maxnz);CHKERRQ(ierr);
1730     if (maxnz != nz) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_FILE_UNEXPECTED,"something is wrong with file");
1731 
1732     /* insert into matrix */
1733     jj      = rstart;
1734     smycols = mycols;
1735     svals   = vals;
1736     for (i=0; i<m; i++) {
1737       ierr     = MatSetValues(newmat,1,&jj,ourlens[i],smycols,svals,INSERT_VALUES);CHKERRQ(ierr);
1738       smycols += ourlens[i];
1739       svals   += ourlens[i];
1740       jj++;
1741     }
1742   }
1743   ierr = PetscFree(ourlens);CHKERRQ(ierr);
1744   ierr = PetscFree(vals);CHKERRQ(ierr);
1745   ierr = PetscFree(mycols);CHKERRQ(ierr);
1746   ierr = PetscFree(rowners);CHKERRQ(ierr);
1747 
1748   ierr = MatAssemblyBegin(newmat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
1749   ierr = MatAssemblyEnd(newmat,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
1750   PetscFunctionReturn(0);
1751 }
1752 
1753 #undef __FUNCT__
1754 #define __FUNCT__ "MatEqual_MPIDense"
1755 PetscErrorCode MatEqual_MPIDense(Mat A,Mat B,PetscBool  *flag)
1756 {
1757   Mat_MPIDense   *matB = (Mat_MPIDense*)B->data,*matA = (Mat_MPIDense*)A->data;
1758   Mat            a,b;
1759   PetscBool      flg;
1760   PetscErrorCode ierr;
1761 
1762   PetscFunctionBegin;
1763   a    = matA->A;
1764   b    = matB->A;
1765   ierr = MatEqual(a,b,&flg);CHKERRQ(ierr);
1766   ierr = MPI_Allreduce(&flg,flag,1,MPIU_BOOL,MPI_LAND,PetscObjectComm((PetscObject)A));CHKERRQ(ierr);
1767   PetscFunctionReturn(0);
1768 }
1769 
1770