xref: /petsc/src/mat/impls/sbaij/mpi/mpiaijsbaij.c (revision 87f3aed42416622aa71bd7563cac15ee0591869d)
1 #define PETSCMAT_DLL
2 
3 #include "mpisbaij.h" /*I "petscmat.h" I*/
4 #include "../src/mat/impls/aij/mpi/mpiaij.h"
5 #include "private/matimpl.h"
6 #include "petscmat.h"
7 
8 EXTERN_C_BEGIN
9 #undef __FUNCT__
10 #define __FUNCT__ "MatConvert_MPIAIJ_MPISBAIJ"
11 PetscErrorCode PETSCMAT_DLLEXPORT MatConvert_MPIAIJ_MPISBAIJ(Mat A, MatType newtype,MatReuse reuse,Mat *newmat)
12 {
13   PetscErrorCode     ierr;
14   Mat                M;
15   PetscInt           *d_nnz,*o_nnz;
16   PetscInt           i,j,k,nz;
17   PetscInt           m,n,lm,ln;
18   PetscInt           rstart,rend;
19   const PetscScalar  *vwork;
20   const PetscInt     *cwork;
21 
22   PetscFunctionBegin;
23   ierr = MatGetSize(A,&m,&n);CHKERRQ(ierr);
24   ierr = MatGetLocalSize(A,&lm,&ln);CHKERRQ(ierr);
25   ierr = PetscMalloc2(lm*sizeof(PetscInt),PetscInt,&d_nnz,lm*sizeof(PetscInt),PetscInt,&o_nnz);CHKERRQ(ierr);
26 
27   k = 0;
28   ierr = MatGetOwnershipRange(A,&rstart,&rend);CHKERRQ(ierr);
29   for(i=rstart;i<rend;i++){
30     ierr = MatGetRow(A,i,&nz,&cwork,&vwork);CHKERRQ(ierr);
31     d_nnz[k] = o_nnz[k] = 0;
32     for(j=0;j<nz;j++){
33       if(cwork[j] >= rstart && cwork[j] <= rend-1){ /* diagonal portion */
34 	if(cwork[j] >= i) d_nnz[k] += 1;
35       } else {
36 	/* insert values only in upper triangular portion */
37 	if(cwork[j] >= rend) o_nnz[k] += 1;  /* off-diagonal portion */
38       }
39     }
40     ierr = MatRestoreRow(A,i,&nz,&cwork,&vwork);CHKERRQ(ierr);
41     k++;
42   }
43 
44   ierr = MatCreate(((PetscObject)A)->comm,&M);CHKERRQ(ierr);
45   ierr = MatSetSizes(M,lm,ln,m,n);CHKERRQ(ierr);
46   ierr = MatSetType(M,newtype);CHKERRQ(ierr);
47   ierr = MatMPISBAIJSetPreallocation(M,1,0,d_nnz,0,o_nnz);CHKERRQ(ierr);
48 
49   ierr = PetscFree2(d_nnz,o_nnz);CHKERRQ(ierr);
50 
51   for(i=rstart;i<rend;i++){
52     ierr = MatGetRow(A,i,&nz,&cwork,&vwork);CHKERRQ(ierr);
53     j = 0;
54     while (cwork[j] < i){ j++; nz--;}
55     ierr = MatSetValues(M,1,&i,nz,cwork+j,vwork+j,INSERT_VALUES);CHKERRQ(ierr);
56     ierr = MatRestoreRow(A,i,&nz,&cwork,&vwork);CHKERRQ(ierr);
57     k++;
58   }
59   ierr = MatAssemblyBegin(M,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
60   ierr = MatAssemblyEnd(M,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
61 
62   if (A->hermitian){
63     ierr = MatSetOption(M,MAT_HERMITIAN,PETSC_TRUE);CHKERRQ(ierr);
64   }
65 
66   if (reuse == MAT_REUSE_MATRIX) {
67     ierr = MatHeaderReplace(A,M);CHKERRQ(ierr);
68   } else {
69     *newmat = M;
70   }
71   PetscFunctionReturn(0);
72 }
73 EXTERN_C_END
74