xref: /petsc/src/mat/tests/ex25.c (revision d5b43468fb8780a8feea140ccd6fa3e6a50411cc)
1 
2 static char help[] = "Tests MatTranspose()\n\n";
3 
4 #include <petscmat.h>
5 
6 int main(int argc, char **args)
7 {
8   Mat         C, A;
9   PetscScalar v;
10   PetscInt    i, j, m = 4, n = 4, Ii, J, Istart, Iend;
11   PetscMPIInt rank, size;
12   PetscBool   equal = PETSC_FALSE;
13 
14   PetscFunctionBeginUser;
15   PetscCall(PetscInitialize(&argc, &args, (char *)0, help));
16   PetscCallMPI(MPI_Comm_rank(PETSC_COMM_WORLD, &rank));
17   PetscCallMPI(MPI_Comm_size(PETSC_COMM_WORLD, &size));
18 
19   PetscCall(PetscOptionsGetInt(NULL, NULL, "-m", &m, NULL));
20   n = m;
21 
22   PetscCall(MatCreateAIJ(PETSC_COMM_WORLD, PETSC_DECIDE, PETSC_DECIDE, m * n, m * n, 5, NULL, 5, NULL, &C));
23 
24   /* create the symmetric matrix for the five point stencil */
25   PetscCall(MatGetOwnershipRange(C, &Istart, &Iend));
26   for (Ii = Istart; Ii < Iend; Ii++) {
27     v = -1.0;
28     i = Ii / n;
29     j = Ii - i * n;
30     if (i > 0) {
31       J = Ii - n;
32       PetscCall(MatSetValues(C, 1, &Ii, 1, &J, &v, INSERT_VALUES));
33     }
34     if (i < m - 1) {
35       J = Ii + n;
36       PetscCall(MatSetValues(C, 1, &Ii, 1, &J, &v, INSERT_VALUES));
37     }
38     if (j > 0) {
39       J = Ii - 1;
40       PetscCall(MatSetValues(C, 1, &Ii, 1, &J, &v, INSERT_VALUES));
41     }
42     if (j < n - 1) {
43       J = Ii + 1;
44       PetscCall(MatSetValues(C, 1, &Ii, 1, &J, &v, INSERT_VALUES));
45     }
46     v = 4.0;
47     PetscCall(MatSetValues(C, 1, &Ii, 1, &Ii, &v, INSERT_VALUES));
48   }
49   PetscCall(MatAssemblyBegin(C, MAT_FINAL_ASSEMBLY));
50   PetscCall(MatAssemblyEnd(C, MAT_FINAL_ASSEMBLY));
51 
52   PetscCall(MatTranspose(C, MAT_INITIAL_MATRIX, &A));
53 
54   PetscCall(MatEqual(C, A, &equal));
55   PetscCheck(equal, PETSC_COMM_SELF, PETSC_ERR_SUP, "C != C^T");
56 
57   PetscCall(MatDestroy(&C));
58   PetscCall(MatDestroy(&A));
59   PetscCall(PetscFinalize());
60   return 0;
61 }
62 
63 /*TEST
64 
65    test:
66 
67 TEST*/
68