Actual source code: ex25.c


  2: static char help[] = "Tests MatTranspose()\n\n";

  4: #include <petscmat.h>

  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;

 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));

 19:   PetscCall(PetscOptionsGetInt(NULL, NULL, "-m", &m, NULL));
 20:   n = m;

 22:   PetscCall(MatCreateAIJ(PETSC_COMM_WORLD, PETSC_DECIDE, PETSC_DECIDE, m * n, m * n, 5, NULL, 5, NULL, &C));

 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));

 52:   PetscCall(MatTranspose(C, MAT_INITIAL_MATRIX, &A));

 54:   PetscCall(MatEqual(C, A, &equal));
 55:   PetscCheck(equal, PETSC_COMM_SELF, PETSC_ERR_SUP, "C != C^T");

 57:   PetscCall(MatDestroy(&C));
 58:   PetscCall(MatDestroy(&A));
 59:   PetscCall(PetscFinalize());
 60:   return 0;
 61: }

 63: /*TEST

 65:    test:

 67: TEST*/