Actual source code: ex22.c
1: static char help[] = "Tests matrix ordering routines.\n\n";
3: #include <petscmat.h>
4: extern PetscErrorCode MatGetOrdering_myordering(Mat, MatOrderingType, IS *, IS *);
6: int main(int argc, char **args)
7: {
8: Mat C, Cperm;
9: PetscInt i, j, m = 5, n = 5, Ii, J, ncols;
10: PetscScalar v;
11: PetscMPIInt size;
12: IS rperm, cperm, icperm;
13: const PetscInt *rperm_ptr, *cperm_ptr, *cols;
14: const PetscScalar *vals;
15: PetscBool TestMyorder = PETSC_FALSE;
17: PetscFunctionBeginUser;
18: PetscCall(PetscInitialize(&argc, &args, (char *)0, help));
19: PetscCallMPI(MPI_Comm_size(PETSC_COMM_WORLD, &size));
20: PetscCheck(size == 1, PETSC_COMM_WORLD, PETSC_ERR_WRONG_MPI_SIZE, "This is a uniprocessor example only!");
22: /* create the matrix for the five point stencil, YET AGAIN */
23: PetscCall(MatCreateSeqAIJ(PETSC_COMM_SELF, m * n, m * n, 5, NULL, &C));
24: PetscCall(MatSetUp(C));
25: for (i = 0; i < m; i++) {
26: for (j = 0; j < n; j++) {
27: v = -1.0;
28: Ii = j + n * i;
29: if (i > 0) {
30: J = Ii - n;
31: PetscCall(MatSetValues(C, 1, &Ii, 1, &J, &v, INSERT_VALUES));
32: }
33: if (i < m - 1) {
34: J = Ii + n;
35: PetscCall(MatSetValues(C, 1, &Ii, 1, &J, &v, INSERT_VALUES));
36: }
37: if (j > 0) {
38: J = Ii - 1;
39: PetscCall(MatSetValues(C, 1, &Ii, 1, &J, &v, INSERT_VALUES));
40: }
41: if (j < n - 1) {
42: J = Ii + 1;
43: PetscCall(MatSetValues(C, 1, &Ii, 1, &J, &v, INSERT_VALUES));
44: }
45: v = 4.0;
46: PetscCall(MatSetValues(C, 1, &Ii, 1, &Ii, &v, INSERT_VALUES));
47: }
48: }
49: PetscCall(MatAssemblyBegin(C, MAT_FINAL_ASSEMBLY));
50: PetscCall(MatAssemblyEnd(C, MAT_FINAL_ASSEMBLY));
52: PetscCall(MatGetOrdering(C, MATORDERINGND, &rperm, &cperm));
53: PetscCall(ISView(rperm, PETSC_VIEWER_STDOUT_SELF));
54: PetscCall(ISDestroy(&rperm));
55: PetscCall(ISDestroy(&cperm));
57: PetscCall(MatGetOrdering(C, MATORDERINGRCM, &rperm, &cperm));
58: PetscCall(ISView(rperm, PETSC_VIEWER_STDOUT_SELF));
59: PetscCall(ISDestroy(&rperm));
60: PetscCall(ISDestroy(&cperm));
62: PetscCall(MatGetOrdering(C, MATORDERINGQMD, &rperm, &cperm));
63: PetscCall(ISView(rperm, PETSC_VIEWER_STDOUT_SELF));
64: PetscCall(ISDestroy(&rperm));
65: PetscCall(ISDestroy(&cperm));
67: /* create Cperm = rperm*C*icperm */
68: PetscCall(PetscOptionsGetBool(NULL, NULL, "-testmyordering", &TestMyorder, NULL));
69: if (TestMyorder) {
70: PetscCall(MatGetOrdering_myordering(C, MATORDERINGQMD, &rperm, &cperm));
71: printf("myordering's rperm:\n");
72: PetscCall(ISView(rperm, PETSC_VIEWER_STDOUT_SELF));
73: PetscCall(ISInvertPermutation(cperm, PETSC_DECIDE, &icperm));
74: PetscCall(ISGetIndices(rperm, &rperm_ptr));
75: PetscCall(ISGetIndices(icperm, &cperm_ptr));
76: PetscCall(MatCreateSeqAIJ(PETSC_COMM_SELF, m * n, m * n, 5, NULL, &Cperm));
77: for (i = 0; i < m * n; i++) {
78: PetscCall(MatGetRow(C, rperm_ptr[i], &ncols, &cols, &vals));
79: for (j = 0; j < ncols; j++) {
80: /* printf(" (%d %d %g)\n",i,cperm_ptr[cols[j]],vals[j]); */
81: PetscCall(MatSetValues(Cperm, 1, &i, 1, &cperm_ptr[cols[j]], &vals[j], INSERT_VALUES));
82: }
83: }
84: PetscCall(MatAssemblyBegin(Cperm, MAT_FINAL_ASSEMBLY));
85: PetscCall(MatAssemblyEnd(Cperm, MAT_FINAL_ASSEMBLY));
86: PetscCall(ISRestoreIndices(rperm, &rperm_ptr));
87: PetscCall(ISRestoreIndices(icperm, &cperm_ptr));
89: PetscCall(ISDestroy(&rperm));
90: PetscCall(ISDestroy(&cperm));
91: PetscCall(ISDestroy(&icperm));
92: PetscCall(MatDestroy(&Cperm));
93: }
95: PetscCall(MatDestroy(&C));
96: PetscCall(PetscFinalize());
97: return 0;
98: }
100: #include <petsc/private/matimpl.h>
101: /* This is modified from MatGetOrdering_Natural() */
102: PetscErrorCode MatGetOrdering_myordering(Mat mat, MatOrderingType type, IS *irow, IS *icol)
103: {
104: PetscInt n, i, *ii;
105: PetscBool done;
106: MPI_Comm comm;
108: PetscFunctionBegin;
109: PetscCall(PetscObjectGetComm((PetscObject)mat, &comm));
110: PetscCall(MatGetRowIJ(mat, 0, PETSC_FALSE, PETSC_TRUE, &n, NULL, NULL, &done));
111: PetscCall(MatRestoreRowIJ(mat, 0, PETSC_FALSE, PETSC_TRUE, NULL, NULL, NULL, &done));
112: if (done) { /* matrix may be "compressed" in symbolic factorization, due to i-nodes or block storage */
113: PetscCall(PetscMalloc1(n, &ii));
114: for (i = 0; i < n; i++) ii[i] = n - i - 1; /* replace your index here */
115: PetscCall(ISCreateGeneral(PETSC_COMM_SELF, n, ii, PETSC_COPY_VALUES, irow));
116: PetscCall(ISCreateGeneral(PETSC_COMM_SELF, n, ii, PETSC_OWN_POINTER, icol));
117: } else SETERRQ(PETSC_COMM_WORLD, PETSC_ERR_SUP, "MatRestoreRowIJ fails!");
118: PetscCall(ISSetPermutation(*irow));
119: PetscCall(ISSetPermutation(*icol));
120: PetscFunctionReturn(PETSC_SUCCESS);
121: }
123: /*TEST
125: test:
127: TEST*/