Actual source code: ex71.c
2: static char help[] = "Passes a sparse matrix to MATLAB.\n\n";
4: #include <petscmat.h>
6: int main(int argc, char **args)
7: {
8: PetscInt m = 4, n = 5, i, j, II, J;
9: PetscScalar one = 1.0, v;
10: Vec x;
11: Mat A;
13: PetscFunctionBeginUser;
14: PetscCall(PetscInitialize(&argc, &args, (char *)0, help));
15: PetscCall(PetscOptionsGetInt(NULL, NULL, "-m", &m, NULL));
16: PetscCall(PetscOptionsGetInt(NULL, NULL, "-n", &n, NULL));
18: PetscCall(MatCreate(PETSC_COMM_WORLD, &A));
19: PetscCall(MatSetSizes(A, PETSC_DECIDE, PETSC_DECIDE, m * n, m * n));
20: PetscCall(MatSetFromOptions(A));
21: PetscCall(MatSetUp(A));
23: for (i = 0; i < m; i++) {
24: for (j = 0; j < n; j++) {
25: v = -1.0;
26: II = j + n * i;
27: if (i > 0) {
28: J = II - n;
29: PetscCall(MatSetValues(A, 1, &II, 1, &J, &v, INSERT_VALUES));
30: }
31: if (i < m - 1) {
32: J = II + n;
33: PetscCall(MatSetValues(A, 1, &II, 1, &J, &v, INSERT_VALUES));
34: }
35: if (j > 0) {
36: J = II - 1;
37: PetscCall(MatSetValues(A, 1, &II, 1, &J, &v, INSERT_VALUES));
38: }
39: if (j < n - 1) {
40: J = II + 1;
41: PetscCall(MatSetValues(A, 1, &II, 1, &J, &v, INSERT_VALUES));
42: }
43: v = 4.0;
44: PetscCall(MatSetValues(A, 1, &II, 1, &II, &v, INSERT_VALUES));
45: }
46: }
47: PetscCall(MatAssemblyBegin(A, MAT_FINAL_ASSEMBLY));
48: PetscCall(MatAssemblyEnd(A, MAT_FINAL_ASSEMBLY));
49: #if defined(PETSC_USE_SOCKET_VIEWER)
50: PetscCall(MatView(A, PETSC_VIEWER_SOCKET_WORLD));
51: #endif
52: PetscCall(VecCreateSeq(PETSC_COMM_SELF, m, &x));
53: PetscCall(VecSet(x, one));
54: #if defined(PETSC_USE_SOCKET_VIEWER)
55: PetscCall(VecView(x, PETSC_VIEWER_SOCKET_WORLD));
56: #endif
58: PetscCall(PetscSleep(30));
60: PetscCall(VecDestroy(&x));
61: PetscCall(MatDestroy(&A));
62: PetscCall(PetscFinalize());
63: return 0;
64: }
66: /*TEST
68: test:
69: TODO: cannot test with socket viewer
71: TEST*/