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