xref: /petsc/src/mat/impls/sbaij/seq/aijsbaij.c (revision 2d9a3abde1e89b7b0ea71014e14313027d435e7a)
159557b74SHong Zhang /*$Id: aijsbaij.c,v 1.9 2001/08/07 03:02:55 balay Exp $*/
259557b74SHong Zhang 
359557b74SHong Zhang #include "src/mat/impls/aij/seq/aij.h"
4861ba921SHong Zhang #include "src/mat/impls/sbaij/seq/sbaij.h"
559557b74SHong Zhang 
659557b74SHong Zhang EXTERN_C_BEGIN
759557b74SHong Zhang #undef __FUNCT__
859557b74SHong Zhang #define __FUNCT__ "MatConvert_SeqAIJ_SeqSBAIJ"
959557b74SHong Zhang int MatConvert_SeqAIJ_SeqSBAIJ(Mat A,MatType newtype,Mat *B)
1059557b74SHong Zhang {
1159557b74SHong Zhang   Mat_SeqAIJ   *a = (Mat_SeqAIJ*)A->data;
12861ba921SHong Zhang   Mat_SeqSBAIJ *b;
13861ba921SHong Zhang   int          ierr,*ai=a->i,*aj,m=A->M,n=A->N,i,j,
14*2d9a3abdSHong Zhang                *bi,*bj,*rowlengths;
15861ba921SHong Zhang   PetscScalar  *av,*bv;
1659557b74SHong Zhang 
1759557b74SHong Zhang   PetscFunctionBegin;
18*2d9a3abdSHong Zhang   if (n != m) SETERRQ(PETSC_ERR_ARG_WRONG,"Matrix must be square");
1959557b74SHong Zhang   if (!a->diag){
2059557b74SHong Zhang     ierr = MatMarkDiagonal_SeqAIJ(A);CHKERRQ(ierr);
2159557b74SHong Zhang   }
2259557b74SHong Zhang 
2359557b74SHong Zhang   ierr = PetscMalloc(m*sizeof(int),&rowlengths);CHKERRQ(ierr);
2459557b74SHong Zhang   for (i=0; i<m; i++) {
2559557b74SHong Zhang     rowlengths[i] = ai[i+1] - a->diag[i];
2659557b74SHong Zhang   }
2759557b74SHong Zhang   ierr = MatCreateSeqSBAIJ(PETSC_COMM_SELF,1,m,n,0,rowlengths,B);CHKERRQ(ierr);
2859557b74SHong Zhang 
2959557b74SHong Zhang   ierr = MatSetOption(*B,MAT_ROW_ORIENTED);CHKERRQ(ierr);
3059557b74SHong Zhang   ierr = MatSetOption(*B,MAT_ROWS_SORTED);CHKERRQ(ierr);
3159557b74SHong Zhang   ierr = MatSetOption(*B,MAT_COLUMNS_SORTED);CHKERRQ(ierr);
3259557b74SHong Zhang 
33861ba921SHong Zhang   b  = (Mat_SeqSBAIJ*)(*B)->data;
34861ba921SHong Zhang   bi = b->i;
35861ba921SHong Zhang   bj = b->j;
36861ba921SHong Zhang   bv = b->a;
37861ba921SHong Zhang 
38861ba921SHong Zhang   bi[0] = 0;
3959557b74SHong Zhang   for (i=0; i<m; i++) {
4059557b74SHong Zhang     aj = a->j + a->diag[i];
4159557b74SHong Zhang     av = a->a + a->diag[i];
42861ba921SHong Zhang     for (j=0; j<rowlengths[i]; j++){
43861ba921SHong Zhang       *bj = *aj; bj++; aj++;
44861ba921SHong Zhang       *bv = *av; bv++; av++;
45861ba921SHong Zhang     }
46861ba921SHong Zhang     bi[i+1]    = bi[i] + rowlengths[i];
47861ba921SHong Zhang     b->ilen[i] = rowlengths[i];
4859557b74SHong Zhang   }
4959557b74SHong Zhang 
5059557b74SHong Zhang   ierr = PetscFree(rowlengths);CHKERRQ(ierr);
5159557b74SHong Zhang   ierr = MatAssemblyBegin(*B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
5259557b74SHong Zhang   ierr = MatAssemblyEnd(*B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
5359557b74SHong Zhang   PetscFunctionReturn(0);
5459557b74SHong Zhang }
5559557b74SHong Zhang EXTERN_C_END
5659557b74SHong Zhang 
57