Actual source code: ex1.c


  2: static char help[] = "Tests various DM routines.\n\n";

  4: #include <petscdm.h>
  5: #include <petscdmda.h>

  7: int main(int argc, char **argv)
  8: {
  9:   PetscMPIInt rank;
 10:   PetscInt    M = 10, N = 8, m = PETSC_DECIDE, n = PETSC_DECIDE;
 11:   DM          da;
 12:   PetscViewer viewer;
 13:   Vec         local, global;
 14:   PetscScalar value;

 17:   PetscInitialize(&argc, &argv, (char *)0, help);
 18:   PetscViewerDrawOpen(PETSC_COMM_WORLD, 0, "", 300, 0, 300, 300, &viewer);

 20:   /* Read options */
 21:   PetscOptionsGetInt(NULL, NULL, "-M", &M, NULL);
 22:   PetscOptionsGetInt(NULL, NULL, "-N", &N, NULL);
 23:   PetscOptionsGetInt(NULL, NULL, "-m", &m, NULL);
 24:   PetscOptionsGetInt(NULL, NULL, "-n", &n, NULL);

 26:   /* Create distributed array and get vectors */
 27:   DMDACreate2d(PETSC_COMM_WORLD, DM_BOUNDARY_NONE, DM_BOUNDARY_NONE, DMDA_STENCIL_BOX, M, N, m, n, 1, 1, NULL, NULL, &da);
 28:   DMSetFromOptions(da);
 29:   DMSetUp(da);
 30:   DMCreateGlobalVector(da, &global);
 31:   DMCreateLocalVector(da, &local);

 33:   value = -3.0;
 34:   VecSet(global, value);
 35:   DMGlobalToLocalBegin(da, global, INSERT_VALUES, local);
 36:   DMGlobalToLocalEnd(da, global, INSERT_VALUES, local);

 38:   MPI_Comm_rank(PETSC_COMM_WORLD, &rank);
 39:   value = rank + 1;
 40:   VecScale(local, value);
 41:   DMLocalToGlobalBegin(da, local, ADD_VALUES, global);
 42:   DMLocalToGlobalEnd(da, local, ADD_VALUES, global);

 44:   VecView(global, PETSC_VIEWER_STDOUT_WORLD);
 45:   DMView(da, viewer);

 47:   /* Free memory */
 48:   PetscViewerDestroy(&viewer);
 49:   VecDestroy(&local);
 50:   VecDestroy(&global);
 51:   DMDestroy(&da);
 52:   PetscFinalize();
 53:   return 0;
 54: }

 56: /*TEST

 58:    test:
 59:       nsize: 2
 60:       args: -nox
 61:       filter: grep -v -i Object

 63:    test:
 64:       suffix: cuda1
 65:       requires: cuda
 66:       args: -dm_vec_type cuda -nox
 67:       filter: grep -v -i Object

 69:    test:
 70:       suffix: cuda2
 71:       nsize: 2
 72:       requires: cuda
 73:       args: -dm_vec_type cuda -nox
 74:       filter: grep -v -i Object

 76: TEST*/