Actual source code: ex107.c


  2: static char help[] = "Test MatCreate() with MAT_STRUCTURE_ONLY .\n\n";

  4: #include <petscmat.h>

  6: int main(int argc, char **argv)
  7: {
  8:   Mat         mat;
  9:   PetscInt    m = 7, n, i, j, rstart, rend;
 10:   PetscMPIInt size;
 11:   PetscScalar v;
 12:   PetscBool   struct_only = PETSC_TRUE;

 14:   PetscFunctionBeginUser;
 15:   PetscCall(PetscInitialize(&argc, &argv, (char *)0, help));
 16:   PetscCallMPI(MPI_Comm_size(PETSC_COMM_WORLD, &size));
 17:   PetscCheck(size == 1, PETSC_COMM_WORLD, PETSC_ERR_WRONG_MPI_SIZE, "This is a uniprocessor example only!");

 19:   PetscCall(PetscViewerPushFormat(PETSC_VIEWER_STDOUT_WORLD, PETSC_VIEWER_ASCII_COMMON));
 20:   PetscCall(PetscOptionsGetInt(NULL, NULL, "-m", &m, NULL));
 21:   PetscCall(PetscOptionsGetBool(NULL, NULL, "-struct_only", &struct_only, NULL));
 22:   n = m;

 24:   /* ------- Assemble matrix, test MatValid() --------- */
 25:   PetscCall(MatCreate(PETSC_COMM_WORLD, &mat));
 26:   PetscCall(MatSetSizes(mat, PETSC_DECIDE, PETSC_DECIDE, m, n));
 27:   PetscCall(MatSetFromOptions(mat));
 28:   if (struct_only) PetscCall(MatSetOption(mat, MAT_STRUCTURE_ONLY, PETSC_TRUE));
 29:   PetscCall(MatSetUp(mat));
 30:   PetscCall(MatGetOwnershipRange(mat, &rstart, &rend));
 31:   for (i = rstart; i < rend; i++) {
 32:     for (j = 0; j < n; j++) {
 33:       v = 10.0 * i + j;
 34:       PetscCall(MatSetValues(mat, 1, &i, 1, &j, &v, INSERT_VALUES));
 35:     }
 36:   }
 37:   PetscCall(MatAssemblyBegin(mat, MAT_FINAL_ASSEMBLY));
 38:   PetscCall(MatAssemblyEnd(mat, MAT_FINAL_ASSEMBLY));
 39:   PetscCall(MatView(mat, PETSC_VIEWER_STDOUT_WORLD));

 41:   /* Free data structures */
 42:   PetscCall(MatDestroy(&mat));
 43:   PetscCall(PetscFinalize());
 44:   return 0;
 45: }

 47: /*TEST

 49:    test:
 50:       output_file: output/ex107.out

 52:    test:
 53:       suffix: 2
 54:       args: -mat_type baij -mat_block_size 2 -m 10

 56: TEST*/