Actual source code: ex37.c

  1: static char help[] = "VecView() with a DMDA1d vector and draw viewer.\n\n";

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

  7: PetscErrorCode apply(void *ctx, PetscInt n, const PetscScalar *x, PetscScalar *y)
  8: {
  9:   PetscInt i;

 11:   for (i = 0; i < n; i++) {
 12:     y[3 * i]     = x[i];
 13:     y[3 * i + 1] = x[i] * x[i];
 14:     y[3 * i + 2] = x[i] * x[i] * x[i];
 15:   }
 16:   return PETSC_SUCCESS;
 17: }

 19: int main(int argc, char **argv)
 20: {
 21:   DM  da;
 22:   Vec global;
 23:   PF  pf;

 25:   PetscFunctionBeginUser;
 26:   PetscCall(PetscInitialize(&argc, &argv, (char *)0, help));
 27:   PetscCall(DMDACreate1d(PETSC_COMM_WORLD, DM_BOUNDARY_NONE, 10, 3, 1, NULL, &da));
 28:   PetscCall(DMSetFromOptions(da));
 29:   PetscCall(DMSetUp(da));
 30:   PetscCall(DMCreateGlobalVector(da, &global));
 31:   PetscCall(PFCreate(PETSC_COMM_WORLD, 1, 3, &pf));
 32:   PetscCall(PFSet(pf, apply, NULL, NULL, NULL, NULL));
 33:   PetscCall(PFApplyVec(pf, NULL, global));
 34:   PetscCall(PFDestroy(&pf));
 35:   PetscCall(VecView(global, PETSC_VIEWER_DRAW_WORLD));
 36:   PetscCall(VecDestroy(&global));
 37:   PetscCall(DMDestroy(&da));
 38:   PetscCall(PetscFinalize());
 39:   return 0;
 40: }

 42: /*TEST

 44:    test:
 45:       nsize: 2
 46:       requires: x

 48: TEST*/