static char help[] = "Test DMClone_Stag()\n\n";

#include <petscdm.h>
#include <petscdmstag.h>

int main(int argc, char **argv)
{
  DM        dm, dm2;
  PetscInt  dim;
  PetscBool flg, setSizes;

  /* Create a DMStag object */
  PetscFunctionBeginUser;
  PetscCall(PetscInitialize(&argc, &argv, NULL, help));
  PetscCall(PetscOptionsGetInt(NULL, NULL, "-dim", &dim, &flg));
  PetscCheck(flg, PETSC_COMM_WORLD, PETSC_ERR_ARG_WRONG, "Supply -dim option with value 1, 2, or 3");
  setSizes = PETSC_FALSE;
  PetscCall(PetscOptionsGetBool(NULL, NULL, "-setsizes", &setSizes, NULL));
  if (setSizes) {
    PetscMPIInt size;
    PetscInt    lx[4] = {2, 3}, ranksx = 2, mx = 5;
    PetscInt    ly[3] = {3, 8, 2}, ranksy = 3, my = 13;
    PetscInt    lz[2] = {2, 4}, ranksz = 2, mz = 6;

    PetscCallMPI(MPI_Comm_size(PETSC_COMM_WORLD, &size));
    switch (dim) {
    case 1:
      PetscCheck(size == ranksx, PETSC_COMM_WORLD, PETSC_ERR_ARG_WRONG, "Must run on %" PetscInt_FMT " ranks with -dim 1 -setSizes", ranksx);
      PetscCall(DMStagCreate1d(PETSC_COMM_WORLD, DM_BOUNDARY_NONE, mx, 1, 1, DMSTAG_STENCIL_BOX, 1, lx, &dm));
      break;
    case 2:
      PetscCheck(size == ranksx * ranksy, PETSC_COMM_WORLD, PETSC_ERR_ARG_WRONG, "Must run on %" PetscInt_FMT " ranks with -dim 2 -setSizes", ranksx * ranksy);
      PetscCall(DMStagCreate2d(PETSC_COMM_WORLD, DM_BOUNDARY_NONE, DM_BOUNDARY_NONE, mx, my, ranksx, ranksy, 1, 1, 1, DMSTAG_STENCIL_BOX, 1, lx, ly, &dm));
      break;
    case 3:
      PetscCheck(size == ranksx * ranksy * ranksz, PETSC_COMM_WORLD, PETSC_ERR_ARG_WRONG, "Must run on %" PetscInt_FMT " ranks with -dim 3 -setSizes", ranksx * ranksy * ranksz);
      PetscCall(DMStagCreate3d(PETSC_COMM_WORLD, DM_BOUNDARY_NONE, DM_BOUNDARY_NONE, DM_BOUNDARY_NONE, mx, my, mz, ranksx, ranksy, ranksz, 1, 1, 1, 1, DMSTAG_STENCIL_BOX, 1, lx, ly, lz, &dm));
      break;
    default:
      SETERRQ(PETSC_COMM_WORLD, PETSC_ERR_SUP, "No support for dimension %" PetscInt_FMT, dim);
    }
  } else {
    if (dim == 1) {
      PetscCall(DMStagCreate1d(PETSC_COMM_WORLD, DM_BOUNDARY_NONE, 2, 2, 3, DMSTAG_STENCIL_BOX, 1, NULL, &dm));
    } else if (dim == 2) {
      PetscCall(DMStagCreate2d(PETSC_COMM_WORLD, DM_BOUNDARY_NONE, DM_BOUNDARY_NONE, 2, 2, PETSC_DECIDE, PETSC_DECIDE, 2, 3, 4, DMSTAG_STENCIL_BOX, 1, NULL, NULL, &dm));
    } else if (dim == 3) {
      PetscCall(DMStagCreate3d(PETSC_COMM_WORLD, DM_BOUNDARY_NONE, DM_BOUNDARY_NONE, DM_BOUNDARY_NONE, 2, 2, 2, PETSC_DECIDE, PETSC_DECIDE, PETSC_DECIDE, 2, 3, 4, 5, DMSTAG_STENCIL_BOX, 1, NULL, NULL, NULL, &dm));
    } else {
      PetscCall(PetscPrintf(PETSC_COMM_WORLD, "Supply -dim option with value 1, 2, or 3\n"));
      return 1;
    }
  }
  PetscCall(DMSetFromOptions(dm));
  PetscCall(DMSetUp(dm));
  PetscCall(DMView(dm, PETSC_VIEWER_STDOUT_WORLD));

  /* Create a cloned DMStag object */
  PetscCall(DMClone(dm, &dm2));
  PetscCall(DMView(dm2, PETSC_VIEWER_STDOUT_WORLD));

  PetscCall(DMDestroy(&dm));
  PetscCall(DMDestroy(&dm2));
  PetscCall(PetscFinalize());
  return 0;
}

/*TEST

   test:
      suffix: 1
      nsize: 1
      args: -dim 1

   test:
      suffix: 2
      nsize: 4
      args: -dim 2

   test:
      suffix: 3
      nsize: 6
      args: -dim 3 -stag_grid_x 3 -stag_grid_y 2 -stag_grid_z 1

   test:
      suffix: 4
      nsize: 2
      args: -dim 1 -setsizes

   test:
      suffix: 5
      nsize: 6
      args: -dim 2 -setsizes

   test:
      suffix: 6
      nsize: 12
      args: -dim 3 -setsizes

TEST*/