Actual source code: sp1wd.c
petsc-3.13.6 2020-09-29
2: #include <petscmat.h>
3: #include <petsc/private/matorderimpl.h>
5: /*
6: MatGetOrdering_1WD - Find the 1-way dissection ordering of a given matrix.
7: */
8: PETSC_INTERN PetscErrorCode MatGetOrdering_1WD(Mat mat,MatOrderingType type,IS *row,IS *col)
9: {
11: PetscInt i,*mask,*xls,nblks,*xblk,*ls,nrow,*perm;
12: const PetscInt *ia,*ja;
13: PetscBool done;
16: MatGetRowIJ(mat,1,PETSC_TRUE,PETSC_TRUE,&nrow,&ia,&ja,&done);
17: if (!done) SETERRQ(PetscObjectComm((PetscObject)mat),PETSC_ERR_SUP,"Cannot get rows for matrix");
19: PetscMalloc5(nrow,&mask,nrow+1,&xls,nrow,&ls,nrow+1,&xblk,nrow,&perm);
20: SPARSEPACKgen1wd(&nrow,ia,ja,mask,&nblks,xblk,perm,xls,ls);
21: MatRestoreRowIJ(mat,1,PETSC_TRUE,PETSC_TRUE,NULL,&ia,&ja,&done);
23: for (i=0; i<nrow; i++) perm[i]--;
25: ISCreateGeneral(PETSC_COMM_SELF,nrow,perm,PETSC_COPY_VALUES,row);
26: ISCreateGeneral(PETSC_COMM_SELF,nrow,perm,PETSC_COPY_VALUES,col);
27: PetscFree5(mask,xls,ls,xblk,perm);
28: return(0);
29: }