Actual source code: shellcnv.c
1: /*$Id: shellcnv.c,v 1.20 2001/08/07 03:02:51 balay Exp $*/
3: #include src/mat/matimpl.h
4: #include src/vec/vecimpl.h
5:
6: #undef __FUNCT__
8: int MatConvert_Shell(Mat oldmat,MatType newtype,Mat *mat)
9: {
10: Vec in,out;
11: int ierr,i,M,m,*rows,start,end;
12: MPI_Comm comm;
13: PetscScalar *array,zero = 0.0,one = 1.0;
18: comm = oldmat->comm;
20: MatGetOwnershipRange(oldmat,&start,&end);
21: VecCreateMPI(comm,end-start,PETSC_DECIDE,&in);
22: VecDuplicate(in,&out);
23: VecGetSize(in,&M);
24: VecGetLocalSize(in,&m);
25: PetscMalloc((m+1)*sizeof(int),&rows);
26: for (i=0; i<m; i++) {rows[i] = start + i;}
28: MatCreate(comm,m,M,M,M,mat);
29: MatSetType(*mat,newtype);
31: for (i=0; i<M; i++) {
32: VecSet(&zero,in);
33: VecSetValues(in,1,&i,&one,INSERT_VALUES);
34: VecAssemblyBegin(in);
35: VecAssemblyEnd(in);
37: MatMult(oldmat,in,out);
38:
39: VecGetArray(out,&array);
40: MatSetValues(*mat,m,rows,1,&i,array,INSERT_VALUES);
41: VecRestoreArray(out,&array);
43: }
44: PetscFree(rows);
45: VecDestroy(in);
46: VecDestroy(out);
47: MatAssemblyBegin(*mat,MAT_FINAL_ASSEMBLY);
48: MatAssemblyEnd(*mat,MAT_FINAL_ASSEMBLY);
49: return(0);
50: }