Actual source code: aijsbaij.c

  1: /*$Id: aijsbaij.c,v 1.9 2001/08/07 03:02:55 balay Exp $*/

 3:  #include src/mat/impls/aij/seq/aij.h
 4:  #include src/mat/impls/sbaij/seq/sbaij.h

  6: EXTERN_C_BEGIN
  9: int MatConvert_SeqAIJ_SeqSBAIJ(Mat A,MatType newtype,Mat *newmat) {
 10:   Mat          B;
 11:   Mat_SeqAIJ   *a = (Mat_SeqAIJ*)A->data;
 12:   Mat_SeqSBAIJ *b;
 13:   int          ierr,*ai=a->i,*aj,m=A->M,n=A->N,i,j,
 14:                *bi,*bj,*rowlengths;
 15:   PetscScalar  *av,*bv;

 18:   if (n != m) SETERRQ(PETSC_ERR_ARG_WRONG,"Matrix must be square");
 19:   if (!a->diag){
 20:     MatMarkDiagonal_SeqAIJ(A);
 21:   }

 23:   PetscMalloc(m*sizeof(int),&rowlengths);
 24:   for (i=0; i<m; i++) {
 25:     rowlengths[i] = ai[i+1] - a->diag[i];
 26:   }
 27:   MatCreateSeqSBAIJ(PETSC_COMM_SELF,1,m,n,0,rowlengths,&B);

 29:   MatSetOption(B,MAT_ROW_ORIENTED);
 30:   MatSetOption(B,MAT_ROWS_SORTED);
 31:   MatSetOption(B,MAT_COLUMNS_SORTED);
 32: 
 33:   b  = (Mat_SeqSBAIJ*)(B->data);
 34:   bi = b->i;
 35:   bj = b->j;
 36:   bv = b->a;

 38:   bi[0] = 0;
 39:   for (i=0; i<m; i++) {
 40:     aj = a->j + a->diag[i];
 41:     av = a->a + a->diag[i];
 42:     for (j=0; j<rowlengths[i]; j++){
 43:       *bj = *aj; bj++; aj++;
 44:       *bv = *av; bv++; av++;
 45:     }
 46:     bi[i+1]    = bi[i] + rowlengths[i];
 47:     b->ilen[i] = rowlengths[i];
 48:   }
 49: 
 50:   PetscFree(rowlengths);
 51:   MatAssemblyBegin(B,MAT_FINAL_ASSEMBLY);
 52:   MatAssemblyEnd(B,MAT_FINAL_ASSEMBLY);

 54:   /* Fake support for "inplace" convert. */
 55:   if (*newmat == A) {
 56:     MatDestroy(A);
 57:   }
 58:   *newmat = B;

 60:   return(0);
 61: }
 62: EXTERN_C_END