Actual source code: ex181.c
1: static char help[] = "Tests MatCreateSubmatrix() with entire matrix, modified from ex59.c.";
3: #include <petscmat.h>
5: int main(int argc, char **args)
6: {
7: Mat C, A, Adup;
8: PetscInt i, j, m = 3, n = 2, rstart, rend;
9: PetscMPIInt size, rank;
10: PetscScalar v;
11: IS isrow;
12: PetscBool detect_bug = PETSC_FALSE;
14: PetscFunctionBeginUser;
15: PetscCall(PetscInitialize(&argc, &args, (char *)0, help));
16: PetscCall(PetscOptionsHasName(NULL, NULL, "-detect_bug", &detect_bug));
17: PetscCallMPI(MPI_Comm_rank(PETSC_COMM_WORLD, &rank));
18: PetscCallMPI(MPI_Comm_size(PETSC_COMM_WORLD, &size));
19: n = 2 * size;
21: PetscCall(MatCreate(PETSC_COMM_WORLD, &C));
22: PetscCall(MatSetSizes(C, PETSC_DECIDE, PETSC_DECIDE, m * n, m * n));
23: PetscCall(MatSetFromOptions(C));
24: PetscCall(MatSetUp(C));
26: /*
27: This is JUST to generate a nice test matrix, all processors fill up
28: the entire matrix. This is not something one would ever do in practice.
29: */
30: PetscCall(MatGetOwnershipRange(C, &rstart, &rend));
31: for (i = rstart; i < rend; i++) {
32: for (j = 0; j < m * n; j++) {
33: v = i + j + 1;
34: PetscCall(MatSetValues(C, 1, &i, 1, &j, &v, INSERT_VALUES));
35: }
36: }
37: PetscCall(MatAssemblyBegin(C, MAT_FINAL_ASSEMBLY));
38: PetscCall(MatAssemblyEnd(C, MAT_FINAL_ASSEMBLY));
39: PetscCall(PetscViewerPushFormat(PETSC_VIEWER_STDOUT_WORLD, PETSC_VIEWER_ASCII_COMMON));
40: PetscCall(MatView(C, PETSC_VIEWER_STDOUT_WORLD));
41: PetscCall(PetscViewerPopFormat(PETSC_VIEWER_STDOUT_WORLD));
43: /*
44: Generate a new matrix consisting every row and column of the original matrix
45: */
46: PetscCall(MatGetOwnershipRange(C, &rstart, &rend));
48: /* Create parallel IS with the rows we want on THIS processor */
49: if (detect_bug && rank == 0) {
50: PetscCall(ISCreateStride(PETSC_COMM_WORLD, 1, rstart, 1, &isrow));
51: } else {
52: PetscCall(ISCreateStride(PETSC_COMM_WORLD, rend - rstart, rstart, 1, &isrow));
53: }
54: PetscCall(MatCreateSubMatrix(C, isrow, NULL, MAT_INITIAL_MATRIX, &A));
56: /* Change C to test the case MAT_REUSE_MATRIX */
57: if (rank == 0) {
58: i = 0;
59: j = 0;
60: v = 100;
61: PetscCall(MatSetValues(C, 1, &i, 1, &j, &v, INSERT_VALUES));
62: }
63: PetscCall(MatAssemblyBegin(C, MAT_FINAL_ASSEMBLY));
64: PetscCall(MatAssemblyEnd(C, MAT_FINAL_ASSEMBLY));
66: PetscCall(MatCreateSubMatrix(C, isrow, NULL, MAT_REUSE_MATRIX, &A));
67: PetscCall(PetscViewerPushFormat(PETSC_VIEWER_STDOUT_WORLD, PETSC_VIEWER_ASCII_COMMON));
68: PetscCall(MatView(A, PETSC_VIEWER_STDOUT_WORLD));
69: PetscCall(PetscViewerPopFormat(PETSC_VIEWER_STDOUT_WORLD));
71: /* Test MatDuplicate */
72: PetscCall(MatDuplicate(A, MAT_COPY_VALUES, &Adup));
73: PetscCall(MatDestroy(&Adup));
75: PetscCall(ISDestroy(&isrow));
76: PetscCall(MatDestroy(&A));
77: PetscCall(MatDestroy(&C));
78: PetscCall(PetscFinalize());
79: return 0;
80: }
82: /*TEST
84: test:
85: nsize: 2
86: filter: grep -v "Mat Object"
87: requires: !complex
89: test:
90: suffix: 2
91: nsize: 3
92: args: -detect_bug
93: filter: grep -v "Mat Object"
94: requires: !complex
96: TEST*/