static char help[] = "Test DMStagPopulateLocalToGlobalInjective.\n\n";

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

static PetscErrorCode Test1(DM dm);
static PetscErrorCode Test2_1d(DM dm);
static PetscErrorCode Test2_2d(DM dm);
static PetscErrorCode Test2_3d(DM dm);

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

  /* Initialize PETSc and process command line arguments */
  PetscFunctionBeginUser;
  PetscCall(PetscInitialize(&argc, &argv, NULL, help));
  dim = 2;
  PetscCall(PetscOptionsGetInt(NULL, NULL, "-dim", &dim, NULL));
  setSizes = PETSC_FALSE;
  PetscCall(PetscOptionsGetBool(NULL, NULL, "-setsizes", &setSizes, NULL));
  useInjective = PETSC_TRUE;
  PetscCall(PetscOptionsGetBool(NULL, NULL, "-useinjective", &useInjective, NULL));

  /* Creation (normal) */
  if (!setSizes) {
    switch (dim) {
    case 1:
      PetscCall(DMStagCreate1d(PETSC_COMM_WORLD, DM_BOUNDARY_NONE, 3, 1, 1, DMSTAG_STENCIL_BOX, 1, NULL, &dm));
      break;
    case 2:
      PetscCall(DMStagCreate2d(PETSC_COMM_WORLD, DM_BOUNDARY_NONE, DM_BOUNDARY_NONE, 3, 2, PETSC_DECIDE, PETSC_DECIDE, 1, 1, 1, DMSTAG_STENCIL_BOX, 1, NULL, NULL, &dm));
      break;
    case 3:
      PetscCall(DMStagCreate3d(PETSC_COMM_WORLD, DM_BOUNDARY_NONE, DM_BOUNDARY_NONE, DM_BOUNDARY_NONE, 3, 2, 4, PETSC_DECIDE, PETSC_DECIDE, PETSC_DECIDE, 1, 1, 1, 1, DMSTAG_STENCIL_BOX, 1, NULL, NULL, NULL, &dm));
      break;
    default:
      SETERRQ(PETSC_COMM_WORLD, PETSC_ERR_SUP, "No support for dimension %" PetscInt_FMT, dim);
    }
  } else {
    /* Creation (test providing decomp exactly)*/
    PetscMPIInt size;
    PetscInt    lx[4] = {2, 3, 4}, ranksx = 3, mx = 9;
    PetscInt    ly[3] = {4, 5}, ranksy = 2, my = 9;
    PetscInt    lz[2] = {6, 7}, ranksz = 2, mz = 13;

    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);
    }
  }

  /* Setup */
  PetscCall(DMSetFromOptions(dm));
  PetscCall(DMSetUp(dm));

  /* Populate Additional Injective Local-to-Global Map */
  if (useInjective) PetscCall(DMStagPopulateLocalToGlobalInjective(dm));

  /* Test: Make sure L2G inverts G2L */
  PetscCall(Test1(dm));

  /* Test: Make sure that G2L inverts L2G, on its domain */
  PetscCall(DMGetDimension(dm, &dim));
  switch (dim) {
  case 1:
    PetscCall(Test2_1d(dm));
    break;
  case 2:
    PetscCall(Test2_2d(dm));
    break;
  case 3:
    PetscCall(Test2_3d(dm));
    break;
  default:
    SETERRQ(PetscObjectComm((PetscObject)dm), PETSC_ERR_SUP, "Not implemented for dimension %" PetscInt_FMT, dim);
  }

  /* Clean up and finalize PETSc */
  PetscCall(DMDestroy(&dm));
  PetscCall(PetscFinalize());
  return 0;
}

static PetscErrorCode Test1(DM dm)
{
  Vec         vecLocal, vecGlobal, vecGlobalCheck;
  PetscRandom rctx;
  PetscBool   equal;

  PetscFunctionBeginUser;
  PetscCall(DMCreateLocalVector(dm, &vecLocal));
  PetscCall(DMCreateGlobalVector(dm, &vecGlobal));
  PetscCall(PetscRandomCreate(PETSC_COMM_WORLD, &rctx));
  PetscCall(VecSetRandom(vecGlobal, rctx));
  PetscCall(VecSetRandom(vecLocal, rctx)); /* garbage */
  PetscCall(PetscRandomDestroy(&rctx));
  PetscCall(VecDuplicate(vecGlobal, &vecGlobalCheck));
  PetscCall(DMGlobalToLocal(dm, vecGlobal, INSERT_VALUES, vecLocal));
  PetscCall(DMLocalToGlobal(dm, vecLocal, INSERT_VALUES, vecGlobalCheck));
  PetscCall(VecEqual(vecGlobal, vecGlobalCheck, &equal));
  PetscCheck(equal, PetscObjectComm((PetscObject)dm), PETSC_ERR_PLIB, "Check failed - vectors should be bitwise identical");
  PetscCall(VecDestroy(&vecLocal));
  PetscCall(VecDestroy(&vecGlobal));
  PetscCall(VecDestroy(&vecGlobalCheck));
  PetscFunctionReturn(PETSC_SUCCESS);
}

/* Test function with positive values for positive arguments */
#define TEST_FUNCTION(i, j, k, idx, c) (8.33 * i + 7.343 * j + 1.234 * idx + 99.011 * c)

/* Helper function to check */
static PetscErrorCode CompareValues(PetscInt i, PetscInt j, PetscInt k, PetscInt c, PetscScalar val, PetscScalar valRef)
{
  PetscFunctionBeginUser;
  PetscCheck(val == valRef || PetscAbsScalar(val - valRef) / PetscAbsScalar(valRef) <= 10 * PETSC_MACHINE_EPSILON, PETSC_COMM_SELF, PETSC_ERR_PLIB, "(%" PetscInt_FMT ",%" PetscInt_FMT ",%" PetscInt_FMT ",%" PetscInt_FMT ") Value %.17g does not match the expected %.17g", i, j, k, c, (double)PetscRealPart(val), (double)PetscRealPart(valRef));
  PetscFunctionReturn(PETSC_SUCCESS);
}

static PetscErrorCode Test2_1d(DM dm)
{
  Vec            vecLocal, vecLocalCheck, vecGlobal;
  PetscInt       i, startx, nx, nExtrax, dof0, dof1, c, idxLeft, idxElement;
  PetscScalar  **arr;
  const PetscInt j = -1, k = -1;

  PetscFunctionBeginUser;
  PetscCall(DMCreateLocalVector(dm, &vecLocal));
  PetscCall(VecSet(vecLocal, -1.0));
  PetscCall(DMStagGetCorners(dm, &startx, NULL, NULL, &nx, NULL, NULL, &nExtrax, NULL, NULL));
  PetscCall(DMStagGetDOF(dm, &dof0, &dof1, NULL, NULL));
  PetscCall(DMStagVecGetArray(dm, vecLocal, &arr));
  if (dof0 > 0) PetscCall(DMStagGetLocationSlot(dm, DMSTAG_LEFT, 0, &idxLeft));
  if (dof1 > 0) PetscCall(DMStagGetLocationSlot(dm, DMSTAG_ELEMENT, 0, &idxElement));
  for (i = startx; i < startx + nx + nExtrax; ++i) {
    for (c = 0; c < dof0; ++c) {
      const PetscScalar valRef = TEST_FUNCTION(i, 0, 0, idxLeft, c);
      arr[i][idxLeft + c]      = valRef;
    }
    if (i < startx + nx) {
      for (c = 0; c < dof1; ++c) {
        const PetscScalar valRef = TEST_FUNCTION(i, 0, 0, idxElement, c);
        arr[i][idxElement + c]   = valRef;
      }
    }
  }
  PetscCall(DMStagVecRestoreArray(dm, vecLocal, &arr));
  PetscCall(DMCreateGlobalVector(dm, &vecGlobal));
  PetscCall(DMLocalToGlobal(dm, vecLocal, INSERT_VALUES, vecGlobal));
  PetscCall(VecDuplicate(vecLocal, &vecLocalCheck));
  PetscCall(VecSet(vecLocalCheck, -1.0));
  PetscCall(DMGlobalToLocal(dm, vecGlobal, INSERT_VALUES, vecLocalCheck));
  PetscCall(DMStagVecGetArrayRead(dm, vecLocalCheck, &arr));
  for (i = startx; i < startx + nx + nExtrax; ++i) {
    for (c = 0; c < dof0; ++c) {
      const PetscScalar valRef = TEST_FUNCTION(i, 0, 0, idxLeft, c);
      const PetscScalar val    = arr[i][idxLeft + c];
      PetscCall(CompareValues(i, j, k, c, val, valRef));
    }
    if (i < startx + nx) {
      for (c = 0; c < dof1; ++c) {
        const PetscScalar valRef = TEST_FUNCTION(i, 0, 0, idxElement, c);
        const PetscScalar val    = arr[i][idxElement + c];
        PetscCall(CompareValues(i, j, k, c, val, valRef));
      }
    } else {
      for (c = 0; c < dof1; ++c) {
        const PetscScalar valRef = -1.0;
        const PetscScalar val    = arr[i][idxElement + c];
        PetscCall(CompareValues(i, j, k, c, val, valRef));
      }
    }
  }
  PetscCall(DMStagVecRestoreArrayRead(dm, vecLocalCheck, &arr));
  PetscCall(VecDestroy(&vecLocal));
  PetscCall(VecDestroy(&vecLocalCheck));
  PetscCall(VecDestroy(&vecGlobal));
  PetscFunctionReturn(PETSC_SUCCESS);
}

static PetscErrorCode Test2_2d(DM dm)
{
  Vec            vecLocal, vecLocalCheck, vecGlobal;
  PetscInt       i, j, startx, starty, nx, ny, nExtrax, nExtray, dof0, dof1, dof2, c, idxLeft, idxDown, idxDownLeft, idxElement;
  PetscScalar ***arr;
  const PetscInt k = -1;

  PetscFunctionBeginUser;
  PetscCall(DMCreateLocalVector(dm, &vecLocal));
  PetscCall(VecSet(vecLocal, -1.0));
  PetscCall(DMStagGetCorners(dm, &startx, &starty, NULL, &nx, &ny, NULL, &nExtrax, &nExtray, NULL));
  PetscCall(DMStagGetDOF(dm, &dof0, &dof1, &dof2, NULL));
  PetscCall(DMStagVecGetArray(dm, vecLocal, &arr));
  if (dof0 > 0) PetscCall(DMStagGetLocationSlot(dm, DMSTAG_DOWN_LEFT, 0, &idxDownLeft));
  if (dof1 > 0) {
    PetscCall(DMStagGetLocationSlot(dm, DMSTAG_LEFT, 0, &idxLeft));
    PetscCall(DMStagGetLocationSlot(dm, DMSTAG_DOWN, 0, &idxDown));
  }
  if (dof2 > 0) PetscCall(DMStagGetLocationSlot(dm, DMSTAG_ELEMENT, 0, &idxElement));
  for (j = starty; j < starty + ny + nExtray; ++j) {
    for (i = startx; i < startx + nx + nExtrax; ++i) {
      for (c = 0; c < dof0; ++c) {
        const PetscScalar valRef   = TEST_FUNCTION(i, j, 0, idxDownLeft, c);
        arr[j][i][idxDownLeft + c] = valRef;
      }
      if (j < starty + ny) {
        for (c = 0; c < dof1; ++c) {
          const PetscScalar valRef = TEST_FUNCTION(i, j, 0, idxLeft, c);
          arr[j][i][idxLeft + c]   = valRef;
        }
      }
      if (i < startx + nx) {
        for (c = 0; c < dof1; ++c) {
          const PetscScalar valRef = TEST_FUNCTION(i, j, 0, idxDown, c);
          arr[j][i][idxDown + c]   = valRef;
        }
      }
      if (i < startx + nx && j < starty + ny) {
        for (c = 0; c < dof2; ++c) {
          const PetscScalar valRef  = TEST_FUNCTION(i, j, 0, idxElement, c);
          arr[j][i][idxElement + c] = valRef;
        }
      }
    }
  }
  PetscCall(DMStagVecRestoreArray(dm, vecLocal, &arr));
  PetscCall(DMCreateGlobalVector(dm, &vecGlobal));
  PetscCall(DMLocalToGlobal(dm, vecLocal, INSERT_VALUES, vecGlobal));
  PetscCall(VecDuplicate(vecLocal, &vecLocalCheck));
  PetscCall(VecSet(vecLocalCheck, -1.0));
  PetscCall(DMGlobalToLocal(dm, vecGlobal, INSERT_VALUES, vecLocalCheck));
  PetscCall(DMStagVecGetArrayRead(dm, vecLocalCheck, &arr));
  for (j = starty; j < starty + ny + nExtray; ++j) {
    for (i = startx; i < startx + nx + nExtrax; ++i) {
      for (c = 0; c < dof0; ++c) {
        const PetscScalar valRef = TEST_FUNCTION(i, j, 0, idxDownLeft, c);
        const PetscScalar val    = arr[j][i][idxDownLeft + c];
        PetscCall(CompareValues(i, j, k, c, val, valRef));
      }
      if (j < starty + ny) {
        for (c = 0; c < dof1; ++c) {
          const PetscScalar valRef = TEST_FUNCTION(i, j, 0, idxLeft, c);
          const PetscScalar val    = arr[j][i][idxLeft + c];
          PetscCall(CompareValues(i, j, k, c, val, valRef));
        }
      } else {
        for (c = 0; c < dof1; ++c) {
          const PetscScalar valRef = -1.0;
          const PetscScalar val    = arr[j][i][idxLeft + c];
          PetscCall(CompareValues(i, j, k, c, val, valRef));
        }
      }
      if (i < startx + nx) {
        for (c = 0; c < dof1; ++c) {
          const PetscScalar valRef = TEST_FUNCTION(i, j, 0, idxDown, c);
          const PetscScalar val    = arr[j][i][idxDown + c];
          PetscCall(CompareValues(i, j, k, c, val, valRef));
        }
      } else {
        for (c = 0; c < dof1; ++c) {
          const PetscScalar valRef = -1.0;
          const PetscScalar val    = arr[j][i][idxDown + c];
          PetscCall(CompareValues(i, j, k, c, val, valRef));
        }
      }
      if (i < startx + nx && j < starty + ny) {
        for (c = 0; c < dof2; ++c) {
          const PetscScalar valRef = TEST_FUNCTION(i, j, 0, idxElement, c);
          const PetscScalar val    = arr[j][i][idxElement + c];
          PetscCall(CompareValues(i, j, k, c, val, valRef));
        }
      } else {
        for (c = 0; c < dof2; ++c) {
          const PetscScalar valRef = -1.0;
          const PetscScalar val    = arr[j][i][idxElement + c];
          PetscCall(CompareValues(i, j, k, c, val, valRef));
        }
      }
    }
  }
  PetscCall(DMStagVecRestoreArrayRead(dm, vecLocalCheck, &arr));
  PetscCall(VecDestroy(&vecLocal));
  PetscCall(VecDestroy(&vecLocalCheck));
  PetscCall(VecDestroy(&vecGlobal));
  PetscFunctionReturn(PETSC_SUCCESS);
}

static PetscErrorCode Test2_3d(DM dm)
{
  Vec             vecLocal, vecLocalCheck, vecGlobal;
  PetscInt        i, j, k, startx, starty, startz, nx, ny, nz, nExtrax, nExtray, nExtraz, dof0, dof1, dof2, dof3, c, idxLeft, idxDown, idxDownLeft, idxBackDownLeft, idxBackDown, idxBack, idxBackLeft, idxElement;
  PetscScalar ****arr;

  PetscFunctionBeginUser;
  PetscCall(DMCreateLocalVector(dm, &vecLocal));
  PetscCall(VecSet(vecLocal, -1.0));
  PetscCall(DMStagGetCorners(dm, &startx, &starty, &startz, &nx, &ny, &nz, &nExtrax, &nExtray, &nExtraz));
  PetscCall(DMStagGetDOF(dm, &dof0, &dof1, &dof2, &dof3));
  PetscCall(DMStagVecGetArray(dm, vecLocal, &arr));
  if (dof0 > 0) PetscCall(DMStagGetLocationSlot(dm, DMSTAG_BACK_DOWN_LEFT, 0, &idxBackDownLeft));
  if (dof1 > 0) {
    PetscCall(DMStagGetLocationSlot(dm, DMSTAG_BACK_LEFT, 0, &idxBackLeft));
    PetscCall(DMStagGetLocationSlot(dm, DMSTAG_BACK_DOWN, 0, &idxBackDown));
    PetscCall(DMStagGetLocationSlot(dm, DMSTAG_DOWN_LEFT, 0, &idxDownLeft));
  }
  if (dof2 > 0) {
    PetscCall(DMStagGetLocationSlot(dm, DMSTAG_LEFT, 0, &idxLeft));
    PetscCall(DMStagGetLocationSlot(dm, DMSTAG_DOWN, 0, &idxDown));
    PetscCall(DMStagGetLocationSlot(dm, DMSTAG_BACK, 0, &idxBack));
  }
  if (dof3 > 0) PetscCall(DMStagGetLocationSlot(dm, DMSTAG_ELEMENT, 0, &idxElement));
  for (k = startz; k < startz + nz + nExtraz; ++k) {
    for (j = starty; j < starty + ny + nExtray; ++j) {
      for (i = startx; i < startx + nx + nExtrax; ++i) {
        for (c = 0; c < dof0; ++c) {
          const PetscScalar valRef          = TEST_FUNCTION(i, j, k, idxBackDownLeft, c);
          arr[k][j][i][idxBackDownLeft + c] = valRef;
        }
        if (k < startz + nz) {
          for (c = 0; c < dof1; ++c) {
            const PetscScalar valRef      = TEST_FUNCTION(i, j, k, idxDownLeft, c);
            arr[k][j][i][idxDownLeft + c] = valRef;
          }
        }
        if (j < starty + ny) {
          for (c = 0; c < dof1; ++c) {
            const PetscScalar valRef      = TEST_FUNCTION(i, j, k, idxBackLeft, c);
            arr[k][j][i][idxBackLeft + c] = valRef;
          }
        }
        if (i < startx + nx) {
          for (c = 0; c < dof1; ++c) {
            const PetscScalar valRef      = TEST_FUNCTION(i, j, k, idxBackDown, c);
            arr[k][j][i][idxBackDown + c] = valRef;
          }
        }
        if (j < starty + ny && k < startz + nz) {
          for (c = 0; c < dof2; ++c) {
            const PetscScalar valRef  = TEST_FUNCTION(i, j, k, idxLeft, c);
            arr[k][j][i][idxLeft + c] = valRef;
          }
        }
        if (i < startx + nx && k < startz + nz) {
          for (c = 0; c < dof2; ++c) {
            const PetscScalar valRef  = TEST_FUNCTION(i, j, k, idxDown, c);
            arr[k][j][i][idxDown + c] = valRef;
          }
        }
        if (i < startx + nx && j < starty + ny) {
          for (c = 0; c < dof2; ++c) {
            const PetscScalar valRef  = TEST_FUNCTION(i, j, k, idxBack, c);
            arr[k][j][i][idxBack + c] = valRef;
          }
        }
        if (i < startx + nx && j < starty + ny && k < startz + nz) {
          for (c = 0; c < dof3; ++c) {
            const PetscScalar valRef     = TEST_FUNCTION(i, j, k, idxElement, c);
            arr[k][j][i][idxElement + c] = valRef;
          }
        }
      }
    }
  }
  PetscCall(DMStagVecRestoreArray(dm, vecLocal, &arr));
  PetscCall(DMCreateGlobalVector(dm, &vecGlobal));
  PetscCall(DMLocalToGlobal(dm, vecLocal, INSERT_VALUES, vecGlobal));
  PetscCall(VecDuplicate(vecLocal, &vecLocalCheck));
  PetscCall(VecSet(vecLocalCheck, -1.0));
  PetscCall(DMGlobalToLocal(dm, vecGlobal, INSERT_VALUES, vecLocalCheck));
  PetscCall(DMStagVecGetArrayRead(dm, vecLocalCheck, &arr));
  for (k = startz; k < startz + nz + nExtraz; ++k) {
    for (j = starty; j < starty + ny + nExtray; ++j) {
      for (i = startx; i < startx + nx + nExtrax; ++i) {
        for (c = 0; c < dof0; ++c) {
          const PetscScalar valRef = TEST_FUNCTION(i, j, k, idxBackDownLeft, c);
          const PetscScalar val    = arr[k][j][i][idxBackDownLeft + c];
          PetscCall(CompareValues(i, j, k, c, val, valRef));
        }
        if (k < startz + nz) {
          for (c = 0; c < dof1; ++c) {
            const PetscScalar valRef = TEST_FUNCTION(i, j, k, idxDownLeft, c);
            const PetscScalar val    = arr[k][j][i][idxDownLeft + c];
            PetscCall(CompareValues(i, j, k, c, val, valRef));
          }
        } else {
          for (c = 0; c < dof1; ++c) {
            const PetscScalar valRef = -1.0;
            const PetscScalar val    = arr[k][j][i][idxDownLeft + c];
            PetscCall(CompareValues(i, j, k, c, val, valRef));
          }
        }
        if (j < starty + ny) {
          for (c = 0; c < dof1; ++c) {
            const PetscScalar valRef = TEST_FUNCTION(i, j, k, idxBackLeft, c);
            const PetscScalar val    = arr[k][j][i][idxBackLeft + c];
            PetscCall(CompareValues(i, j, k, c, val, valRef));
          }
        } else {
          for (c = 0; c < dof1; ++c) {
            const PetscScalar valRef = -1.0;
            const PetscScalar val    = arr[k][j][i][idxBackLeft + c];
            PetscCall(CompareValues(i, j, k, c, val, valRef));
          }
        }
        if (i < startx + nx) {
          for (c = 0; c < dof1; ++c) {
            const PetscScalar valRef = TEST_FUNCTION(i, j, k, idxBackDown, c);
            const PetscScalar val    = arr[k][j][i][idxBackDown + c];
            PetscCall(CompareValues(i, j, k, c, val, valRef));
          }
        } else {
          for (c = 0; c < dof1; ++c) {
            const PetscScalar valRef = -1.0;
            const PetscScalar val    = arr[k][j][i][idxBackDown + c];
            PetscCall(CompareValues(i, j, k, c, val, valRef));
          }
        }
        if (j < starty + ny && k < startz + nz) {
          for (c = 0; c < dof2; ++c) {
            const PetscScalar valRef = TEST_FUNCTION(i, j, k, idxLeft, c);
            const PetscScalar val    = arr[k][j][i][idxLeft + c];
            PetscCall(CompareValues(i, j, k, c, val, valRef));
          }
        } else {
          for (c = 0; c < dof2; ++c) {
            const PetscScalar valRef = -1.0;
            const PetscScalar val    = arr[k][j][i][idxLeft + c];
            PetscCall(CompareValues(i, j, k, c, val, valRef));
          }
        }
        if (i < startx + nx && k < startz + nz) {
          for (c = 0; c < dof2; ++c) {
            const PetscScalar valRef = TEST_FUNCTION(i, j, k, idxDown, c);
            const PetscScalar val    = arr[k][j][i][idxDown + c];
            PetscCall(CompareValues(i, j, k, c, val, valRef));
          }
        } else {
          for (c = 0; c < dof2; ++c) {
            const PetscScalar valRef = -1.0;
            const PetscScalar val    = arr[k][j][i][idxDown + c];
            PetscCall(CompareValues(i, j, k, c, val, valRef));
          }
        }
        if (i < startx + nx && j < starty + ny) {
          for (c = 0; c < dof2; ++c) {
            const PetscScalar valRef = TEST_FUNCTION(i, j, k, idxBack, c);
            const PetscScalar val    = arr[k][j][i][idxBack + c];
            PetscCall(CompareValues(i, j, k, c, val, valRef));
          }
        } else {
          for (c = 0; c < dof2; ++c) {
            const PetscScalar valRef = -1.0;
            const PetscScalar val    = arr[k][j][i][idxBack + c];
            PetscCall(CompareValues(i, j, k, c, val, valRef));
          }
        }
        if (i < startx + nx && j < starty + ny && k < startz + nz) {
          for (c = 0; c < dof3; ++c) {
            const PetscScalar valRef = TEST_FUNCTION(i, j, k, idxElement, c);
            const PetscScalar val    = arr[k][j][i][idxElement + c];
            PetscCall(CompareValues(i, j, k, c, val, valRef));
          }
        } else {
          for (c = 0; c < dof3; ++c) {
            const PetscScalar valRef = -1.0;
            const PetscScalar val    = arr[k][j][i][idxElement + c];
            PetscCall(CompareValues(i, j, k, c, val, valRef));
          }
        }
      }
    }
  }
  PetscCall(DMStagVecRestoreArrayRead(dm, vecLocalCheck, &arr));
  PetscCall(VecDestroy(&vecLocal));
  PetscCall(VecDestroy(&vecLocalCheck));
  PetscCall(VecDestroy(&vecGlobal));
  PetscFunctionReturn(PETSC_SUCCESS);
}
#undef TEST_FUNCTION

/*TEST

   testset:
      suffix: periodic_1d_seq
      nsize: 1
      args: -dm_view -dim 1 -stag_grid_x 4 -stag_boundary_type_x periodic -stag_stencil_width {{0 1 2}separate output}

   testset:
      suffix: ghosted_1d_seq
      nsize: 1
      args: -dm_view -dim 1 -stag_grid_x 4 -stag_boundary_type_x ghosted -stag_stencil_width {{0 1 2}separate output}

   testset:
      suffix: none_1d_seq
      nsize: 1
      args: -dm_view -dim 1 -stag_grid_x 4 -stag_boundary_type_x ghosted -stag_stencil_width {{0 1 2}separate output}

   testset:
      suffix: periodic_1d_par
      nsize: 3
      args: -dm_view -dim 1 -setsizes -stag_boundary_type_x periodic -stag_stencil_width {{0 1 2}separate output}

   testset:
      suffix: ghosted_1d_par
      nsize: 3
      args: -dm_view -dim 1 -setsizes -stag_boundary_type_x ghosted -stag_stencil_width {{0 1 2}separate output}

   testset:
      suffix: none_1d_par
      nsize: 3
      args: -dm_view -dim 1 -setsizes -stag_boundary_type_x ghosted -stag_stencil_width {{0 1 2}separate output}

   testset:
      suffix: periodic_periodic_2d_seq
      nsize: 1
      args: -dm_view -dim 2 -stag_grid_x 4 -stag_grid_y 5 -stag_boundary_type_x periodic -stag_boundary_type_y periodic -stag_stencil_width {{0 1 2}separate output}

   testset:
      suffix: periodic_ghosted_2d_seq
      nsize: 1
      args: -dm_view -dim 2 -stag_grid_x 4 -stag_grid_y 5 -stag_boundary_type_x periodic -stag_boundary_type_y ghosted -stag_stencil_width {{0 1 2}separate output}

   testset:
      suffix: none_none_2d_seq
      nsize: 1
      args: -dm_view -dim 2 -stag_grid_x 4 -stag_grid_y 5 -stag_boundary_type_x none -stag_boundary_type_y none -stag_stencil_width {{0 1 2}separate output}

   testset:
      suffix: none_ghosted_2d_seq
      nsize: 1
      args: -dm_view -dim 2 -stag_grid_x 4 -stag_grid_y 5 -stag_boundary_type_x none -stag_boundary_type_y ghosted -stag_stencil_width {{0 1 2}separate output}

   testset:
      suffix: none_periodic_2d_seq
      nsize: 1
      args: -dm_view -dim 2 -stag_grid_x 4 -stag_grid_y 5 -stag_boundary_type_x none -stag_boundary_type_y periodic -stag_stencil_width {{0 1 2}separate output}

   testset:
      suffix: periodic_periodic_2d_par
      nsize: 6
      args: -dm_view -dim 2 -setsizes -stag_boundary_type_x periodic -stag_boundary_type_y periodic -stag_stencil_width {{0 1 2}separate output}

   testset:
      suffix: periodic_ghosted_2d_par
      nsize: 6
      args: -dm_view -dim 2 -setsizes -stag_boundary_type_x periodic -stag_boundary_type_y ghosted -stag_stencil_width {{0 1 2}separate output}

   testset:
      suffix: none_none_2d_par
      nsize: 6
      args: -dm_view -dim 2 -setsizes -stag_boundary_type_x none -stag_boundary_type_y none -stag_stencil_width {{0 1 2}separate output}

   testset:
      suffix: none_ghosted_2d_par
      nsize: 6
      args: -dm_view -dim 2 -setsizes -stag_boundary_type_x none -stag_boundary_type_y ghosted -stag_stencil_width {{0 1 2}separate output}

   testset:
      suffix: none_periodic_2d_par
      nsize: 6
      args: -dm_view -dim 2 -setsizes -stag_boundary_type_x none -stag_boundary_type_y periodic -stag_stencil_width {{0 1 2}separate output}

   testset:
      suffix: periodic_periodic_periodic_3d_seq
      nsize: 1
      args: -dm_view -dim 3 -stag_grid_x 4 -stag_grid_y 5 -stag_grid_z 3 -stag_boundary_type_x periodic -stag_boundary_type_y periodic -stag_boundary_type_z periodic -stag_stencil_width {{0 1 2}separate output}

   testset:
      suffix: periodic_ghosted_periodic_3d_seq
      nsize: 1
      args: -dm_view -dim 3 -stag_grid_x 4 -stag_grid_y 5 -stag_grid_z 3 -stag_boundary_type_x periodic -stag_boundary_type_y ghosted -stag_boundary_type_z periodic -stag_stencil_width {{0 1 2}separate output}

   testset:
      suffix: none_periodic_ghosted_3d_seq
      nsize: 1
      args: -dm_view -dim 3 -stag_grid_x 4 -stag_grid_y 5 -stag_grid_z 3 -stag_boundary_type_x none -stag_boundary_type_y periodic -stag_boundary_type_z ghosted -stag_stencil_width {{0 1 2}separate output}

   testset:
      suffix: none_none_none_3d_seq
      nsize: 1
      args: -dm_view -dim 3 -stag_grid_x 4 -stag_grid_y 5 -stag_grid_z 3 -stag_boundary_type_x none -stag_boundary_type_y none -stag_boundary_type_z none -stag_stencil_width {{0 1 2}separate output}

   testset:
      suffix: periodic_periodic_periodic_3d_par
      nsize: 12
      args: -dm_view -dim 3 -setsizes -stag_boundary_type_x periodic -stag_boundary_type_y periodic -stag_boundary_type_z periodic -stag_stencil_width {{0 1 2}separate output}

   testset:
      suffix: periodic_ghosted_ghosted_3d_par
      nsize: 12
      args: -dm_view -dim 3 -setsizes -stag_boundary_type_x periodic -stag_boundary_type_y ghosted -stag_boundary_type_z ghosted -stag_stencil_width {{0 1 2}separate output}

   testset:
      suffix: ghosted_periodic_periodic_3d_par
      nsize: 12
      args: -dm_view -dim 3 -setsizes -stag_boundary_type_x ghosted -stag_boundary_type_y periodic -stag_boundary_type_z periodic -stag_stencil_width {{0 1 2}separate output}

   testset:
      suffix: none_none_none_3d_par
      nsize: 12
      args: -dm_view -dim 3 -setsizes -stag_boundary_type_x none -stag_boundary_type_y none -stag_boundary_type_z none -stag_stencil_width {{0 1 2}separate output}

   test:
      suffix: periodic_none_none_3d_skinny_seq
      nsize: 1
      args: -dm_view -dim 3 -stag_boundary_type_x periodic -stag_boundary_type_y none -stag_boundary_type_z none -stag_grid_x 3 -stag_grid_y 6 -stag_grid_z 5 -stag_stencil_width 1 -useinjective 0

   test:
      suffix: periodic_none_none_3d_skinny_par
      nsize: 4
      args: -dm_view -dim 3 -stag_boundary_type_x periodic -stag_boundary_type_y none -stag_boundary_type_z none -stag_grid_x 3 -stag_grid_y 6 -stag_grid_z 5 -stag_ranks_x 1 -stag_ranks_y 2 -stag_ranks_z 2 -stag_stencil_width 1 -useinjective 0

TEST*/
