Actual source code: ex181.c
2: static char help[] = "Tests MatCreateSubmatrix() with entire matrix, modified from ex59.c.";
4: #include <petscmat.h>
6: int main(int argc, char **args)
7: {
8: Mat C, A, Adup;
9: PetscInt i, j, m = 3, n = 2, rstart, rend;
10: PetscMPIInt size, rank;
11: PetscScalar v;
12: IS isrow;
13: PetscBool detect_bug = PETSC_FALSE;
15: PetscFunctionBeginUser;
16: PetscCall(PetscInitialize(&argc, &args, (char *)0, help));
17: PetscCall(PetscOptionsHasName(NULL, NULL, "-detect_bug", &detect_bug));
18: PetscCallMPI(MPI_Comm_rank(PETSC_COMM_WORLD, &rank));
19: PetscCallMPI(MPI_Comm_size(PETSC_COMM_WORLD, &size));
20: n = 2 * size;
22: PetscCall(MatCreate(PETSC_COMM_WORLD, &C));
23: PetscCall(MatSetSizes(C, PETSC_DECIDE, PETSC_DECIDE, m * n, m * n));
24: PetscCall(MatSetFromOptions(C));
25: PetscCall(MatSetUp(C));
27: /*
28: This is JUST to generate a nice test matrix, all processors fill up
29: the entire matrix. This is not something one would ever do in practice.
30: */
31: PetscCall(MatGetOwnershipRange(C, &rstart, &rend));
32: for (i = rstart; i < rend; i++) {
33: for (j = 0; j < m * n; j++) {
34: v = i + j + 1;
35: PetscCall(MatSetValues(C, 1, &i, 1, &j, &v, INSERT_VALUES));
36: }
37: }
38: PetscCall(MatAssemblyBegin(C, MAT_FINAL_ASSEMBLY));
39: PetscCall(MatAssemblyEnd(C, MAT_FINAL_ASSEMBLY));
40: PetscCall(PetscViewerPushFormat(PETSC_VIEWER_STDOUT_WORLD, PETSC_VIEWER_ASCII_COMMON));
41: PetscCall(MatView(C, PETSC_VIEWER_STDOUT_WORLD));
42: PetscCall(PetscViewerPopFormat(PETSC_VIEWER_STDOUT_WORLD));
44: /*
45: Generate a new matrix consisting every row and column of the original matrix
46: */
47: PetscCall(MatGetOwnershipRange(C, &rstart, &rend));
49: /* Create parallel IS with the rows we want on THIS processor */
50: if (detect_bug && rank == 0) {
51: PetscCall(ISCreateStride(PETSC_COMM_WORLD, 1, rstart, 1, &isrow));
52: } else {
53: PetscCall(ISCreateStride(PETSC_COMM_WORLD, rend - rstart, rstart, 1, &isrow));
54: }
55: PetscCall(MatCreateSubMatrix(C, isrow, NULL, MAT_INITIAL_MATRIX, &A));
57: /* Change C to test the case MAT_REUSE_MATRIX */
58: if (rank == 0) {
59: i = 0;
60: j = 0;
61: v = 100;
62: PetscCall(MatSetValues(C, 1, &i, 1, &j, &v, INSERT_VALUES));
63: }
64: PetscCall(MatAssemblyBegin(C, MAT_FINAL_ASSEMBLY));
65: PetscCall(MatAssemblyEnd(C, MAT_FINAL_ASSEMBLY));
67: PetscCall(MatCreateSubMatrix(C, isrow, NULL, MAT_REUSE_MATRIX, &A));
68: PetscCall(PetscViewerPushFormat(PETSC_VIEWER_STDOUT_WORLD, PETSC_VIEWER_ASCII_COMMON));
69: PetscCall(MatView(A, PETSC_VIEWER_STDOUT_WORLD));
70: PetscCall(PetscViewerPopFormat(PETSC_VIEWER_STDOUT_WORLD));
72: /* Test MatDuplicate */
73: PetscCall(MatDuplicate(A, MAT_COPY_VALUES, &Adup));
74: PetscCall(MatDestroy(&Adup));
76: PetscCall(ISDestroy(&isrow));
77: PetscCall(MatDestroy(&A));
78: PetscCall(MatDestroy(&C));
79: PetscCall(PetscFinalize());
80: return 0;
81: }
83: /*TEST
85: test:
86: nsize: 2
87: filter: grep -v "Mat Object"
88: requires: !complex
90: test:
91: suffix: 2
92: nsize: 3
93: args: -detect_bug
94: filter: grep -v "Mat Object"
95: requires: !complex
97: TEST*/