Actual source code: sp1wd.c
1: #include <petscmat.h>
2: #include <petsc/private/matorderimpl.h>
4: /*
5: MatGetOrdering_1WD - Find the 1-way dissection ordering of a given matrix.
6: */
7: PETSC_INTERN PetscErrorCode MatGetOrdering_1WD(Mat mat, MatOrderingType type, IS *row, IS *col)
8: {
9: PetscInt i, *mask, *xls, nblks, *xblk, *ls, nrow, *perm;
10: const PetscInt *ia, *ja;
11: PetscBool done;
13: PetscFunctionBegin;
14: PetscCall(MatGetRowIJ(mat, 1, PETSC_TRUE, PETSC_TRUE, &nrow, &ia, &ja, &done));
15: PetscCheck(done, PetscObjectComm((PetscObject)mat), PETSC_ERR_SUP, "Cannot get rows for matrix");
17: PetscCall(PetscMalloc5(nrow, &mask, nrow + 1, &xls, nrow, &ls, nrow + 1, &xblk, nrow, &perm));
18: PetscCall(SPARSEPACKgen1wd(&nrow, ia, ja, mask, &nblks, xblk, perm, xls, ls));
19: PetscCall(MatRestoreRowIJ(mat, 1, PETSC_TRUE, PETSC_TRUE, NULL, &ia, &ja, &done));
21: for (i = 0; i < nrow; i++) perm[i]--;
23: PetscCall(ISCreateGeneral(PETSC_COMM_SELF, nrow, perm, PETSC_COPY_VALUES, row));
24: PetscCall(ISCreateGeneral(PETSC_COMM_SELF, nrow, perm, PETSC_COPY_VALUES, col));
25: PetscCall(PetscFree5(mask, xls, ls, xblk, perm));
26: PetscFunctionReturn(PETSC_SUCCESS);
27: }