Actual source code: sp1wd.c

      1: #define PETSCMAT_DLL

     3:  #include petscmat.h
     4:  #include src/mat/order/order.h

      7: /*
      8:     MatOrdering_1WD - Find the 1-way dissection ordering of a given matrix.
      9: */
     12: PetscErrorCode PETSCMAT_DLLEXPORT MatOrdering_1WD(Mat mat,const MatOrderingType type,IS *row,IS *col)
     13: {
     15:   PetscInt       i,*mask,*xls,nblks,*xblk,*ls,nrow,*perm,*ia,*ja;
     16:   PetscTruth     done;

     19:   MatGetRowIJ(mat,1,PETSC_TRUE,&nrow,&ia,&ja,&done);
     20:   if (!done) SETERRQ(PETSC_ERR_SUP,"Cannot get rows for matrix");

     22:   PetscMalloc((5*nrow+1) * sizeof(PetscInt),&mask);
     23:   xls  = mask + nrow;
     24:   ls   = xls + nrow + 1;
     25:   xblk = ls + nrow;
     26:   perm = xblk + nrow;
     27:   SPARSEPACKgen1wd(&nrow,ia,ja,mask,&nblks,xblk,perm,xls,ls);
     28:   MatRestoreRowIJ(mat,1,PETSC_TRUE,&nrow,&ia,&ja,&done);

     30:   for (i=0; i<nrow; i++) perm[i]--;

     32:   ISCreateGeneral(PETSC_COMM_SELF,nrow,perm,row);
     33:   ISCreateGeneral(PETSC_COMM_SELF,nrow,perm,col);
     34:   PetscFree(mask);

     36:   return(0);
     37: }