xref: /petsc/src/mat/utils/convert.c (revision 1a0cae60fb91c8e2ce9276d969629479e2ae5b13)
156fe5c5cSLois Curfman McInnes 
2b45d2f2cSJed Brown #include <petsc-private/matimpl.h>
38b6375c0SLois Curfman McInnes 
44a2ae208SSatish Balay #undef __FUNCT__
54a2ae208SSatish Balay #define __FUNCT__ "MatConvert_Basic"
68b6375c0SLois Curfman McInnes /*
78b6375c0SLois Curfman McInnes   MatConvert_Basic - Converts from any input format to another format. For
88b6375c0SLois Curfman McInnes   parallel formats, the new matrix distribution is determined by PETSc.
9273d9f13SBarry Smith 
10273d9f13SBarry Smith   Does not do preallocation so in general will be slow
118b6375c0SLois Curfman McInnes  */
1219fd82e9SBarry Smith PetscErrorCode MatConvert_Basic(Mat mat, MatType newtype,MatReuse reuse,Mat *newmat)
13b3cc6726SBarry Smith {
14676c34cdSKris Buschelman   Mat               M;
15b3cc6726SBarry Smith   const PetscScalar *vwork;
16dfbe8321SBarry Smith   PetscErrorCode    ierr;
17*1a0cae60SJed Brown   PetscInt          i,j,nz,m,n,rstart,rend,lm,ln,prbs,pcbs,cstart,cend,*dnz,*onz;
18c1ac3661SBarry Smith   const PetscInt    *cwork;
19*1a0cae60SJed Brown   PetscBool         isseqsbaij,ismpisbaij,isseqbaij,ismpibaij;
2025cdf11fSBarry Smith 
213a40ed3dSBarry Smith   PetscFunctionBegin;
228b6375c0SLois Curfman McInnes   ierr = MatGetSize(mat,&m,&n);CHKERRQ(ierr);
23435da068SBarry Smith   ierr = MatGetLocalSize(mat,&lm,&ln);CHKERRQ(ierr);
24273d9f13SBarry Smith 
25435da068SBarry Smith   if (ln == n) ln = PETSC_DECIDE; /* try to preserve column ownership */
26435da068SBarry Smith 
27ce94432eSBarry Smith   ierr = MatCreate(PetscObjectComm((PetscObject)mat),&M);CHKERRQ(ierr);
28f69a0ea3SMatthew Knepley   ierr = MatSetSizes(M,lm,ln,m,n);CHKERRQ(ierr);
29*1a0cae60SJed Brown   ierr = MatSetBlockSizes(M,mat->rmap->bs,mat->cmap->bs);CHKERRQ(ierr);
30676c34cdSKris Buschelman   ierr = MatSetType(M,newtype);CHKERRQ(ierr);
31251f4c67SDmitry Karpeev   ierr = PetscObjectTypeCompare((PetscObject)M,MATSEQSBAIJ,&isseqsbaij);CHKERRQ(ierr);
32251f4c67SDmitry Karpeev   ierr = PetscObjectTypeCompare((PetscObject)M,MATMPISBAIJ,&ismpisbaij);CHKERRQ(ierr);
33d1bf975fSJed Brown   if (isseqsbaij || ismpisbaij) {ierr = MatSetOption(M,MAT_IGNORE_LOWER_TRIANGULAR,PETSC_TRUE);CHKERRQ(ierr);}
34*1a0cae60SJed Brown   ierr = PetscObjectTypeCompare((PetscObject)M,MATSEQBAIJ,&isseqbaij);CHKERRQ(ierr);
35*1a0cae60SJed Brown   ierr = PetscObjectTypeCompare((PetscObject)M,MATMPIBAIJ,&ismpibaij);CHKERRQ(ierr);
36273d9f13SBarry Smith 
37*1a0cae60SJed Brown   /* Preallocation block sizes.  (S)BAIJ matrices will have one index per block. */
38*1a0cae60SJed Brown   prbs = (isseqbaij || ismpibaij || isseqsbaij || ismpisbaij) ? M->rmap->bs : 1;
39*1a0cae60SJed Brown   pcbs = (isseqbaij || ismpibaij || isseqsbaij || ismpisbaij) ? M->cmap->bs : 1;
40*1a0cae60SJed Brown 
41*1a0cae60SJed Brown   ierr = PetscMalloc2(lm/prbs,PetscInt,&dnz,lm/prbs,PetscInt,&onz);CHKERRQ(ierr);
42f1af5d2fSBarry Smith   ierr = MatGetOwnershipRange(mat,&rstart,&rend);CHKERRQ(ierr);
43*1a0cae60SJed Brown   ierr = MatGetOwnershipRangeColumn(mat,&cstart,&cend);CHKERRQ(ierr);
44*1a0cae60SJed Brown   for (i=0; i<lm; i+=prbs) {
45*1a0cae60SJed Brown     ierr = MatGetRow(mat,rstart+i,&nz,&cwork,NULL);CHKERRQ(ierr);
46*1a0cae60SJed Brown     dnz[i] = 0;
47*1a0cae60SJed Brown     onz[i] = 0;
48*1a0cae60SJed Brown     for (j=0; j<nz; j+=pcbs) {
49*1a0cae60SJed Brown       if ((isseqsbaij || ismpisbaij) && cwork[j] < rstart+i) continue;
50*1a0cae60SJed Brown       if (cstart <= cwork[j] && cwork[j] < cend) dnz[i]++;
51*1a0cae60SJed Brown       else                                       onz[i]++;
52*1a0cae60SJed Brown     }
53*1a0cae60SJed Brown     ierr = MatRestoreRow(mat,rstart+i,&nz,&cwork,NULL);CHKERRQ(ierr);
54*1a0cae60SJed Brown   }
55*1a0cae60SJed Brown   ierr = MatXAIJSetPreallocation(M,M->rmap->bs,dnz,onz,dnz,onz);CHKERRQ(ierr);
56*1a0cae60SJed Brown   ierr = PetscFree2(dnz,onz);CHKERRQ(ierr);
57*1a0cae60SJed Brown 
588b6375c0SLois Curfman McInnes   for (i=rstart; i<rend; i++) {
598b6375c0SLois Curfman McInnes     ierr = MatGetRow(mat,i,&nz,&cwork,&vwork);CHKERRQ(ierr);
60676c34cdSKris Buschelman     ierr = MatSetValues(M,1,&i,nz,cwork,vwork,INSERT_VALUES);CHKERRQ(ierr);
618b6375c0SLois Curfman McInnes     ierr = MatRestoreRow(mat,i,&nz,&cwork,&vwork);CHKERRQ(ierr);
628b6375c0SLois Curfman McInnes   }
63676c34cdSKris Buschelman   ierr = MatAssemblyBegin(M,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
64676c34cdSKris Buschelman   ierr = MatAssemblyEnd(M,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
65676c34cdSKris Buschelman 
66ceb03754SKris Buschelman   if (reuse == MAT_REUSE_MATRIX) {
678ab5b326SKris Buschelman     ierr = MatHeaderReplace(mat,M);CHKERRQ(ierr);
68c3d102feSKris Buschelman   } else {
6918f87311SHong Zhang     *newmat = M;
70c3d102feSKris Buschelman   }
713a40ed3dSBarry Smith   PetscFunctionReturn(0);
728b6375c0SLois Curfman McInnes }
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