xref: /petsc/src/dm/impls/da/dagetarray.c (revision d083f849a86f1f43e18d534ee43954e2786cb29a)

#include <petsc/private/dmdaimpl.h>    /*I   "petscdmda.h"   I*/

/*@C
   DMDAVecGetArray - Returns a multiple dimension array that shares data with
      the underlying vector and is indexed using the global dimensions.

   Logically collective on da

   Input Parameter:
+  da - the distributed array
-  vec - the vector, either a vector the same size as one obtained with DMCreateGlobalVector() or DMCreateLocalVector()

   Output Parameter:
.  array - the array

   Notes:
    Call DMDAVecRestoreArray() once you have finished accessing the vector entries.

    In C, the indexing is "backwards" from what expects: array[k][j][i] NOT array[i][j][k]!

    If vec is a local vector (obtained with DMCreateLocalVector() etc) then the ghost point locations are accessible. If it is
    a global vector then the ghost points are not accessible. Of course with the local vector you will have had to do the

    appropriate DMGlobalToLocalBegin() and DMGlobalToLocalEnd() to have correct values in the ghost locations.

  Fortran Notes:
    From Fortran use DMDAVecGetArrayF90() and pass for the array type PetscScalar,pointer :: array(:,...,:) of the appropriate
       dimension. For a DMDA created with a dof of 1 use the dimension of the DMDA, for a DMDA created with a dof greater than 1 use one more than the
       dimension of the DMDA. The order of the indices is array(xs:xs+xm-1,ys:ys+ym-1,zs:zs+zm-1) (when dof is 1) otherwise
       array(0:dof-1,xs:xs+xm-1,ys:ys+ym-1,zs:zs+zm-1) where the values are obtained from
       DMDAGetCorners() for a global array or DMDAGetGhostCorners() for a local array. Include petsc/finclude/petscdmda.h90 to access this routine.

  Due to bugs in the compiler DMDAVecGetArrayF90() does not work with gfortran versions before 4.5

  Level: intermediate

.seealso: DMDAGetGhostCorners(), DMDAGetCorners(), VecGetArray(), VecRestoreArray(), DMDAVecRestoreArray(), DMDAVecRestoreArrayDOF()
          DMDAVecGetArrayDOF()
@*/
PetscErrorCode  DMDAVecGetArray(DM da,Vec vec,void *array)
{
  PetscErrorCode ierr;
  PetscInt       xs,ys,zs,xm,ym,zm,gxs,gys,gzs,gxm,gym,gzm,N,dim,dof;

  PetscFunctionBegin;
  PetscValidHeaderSpecificType(da, DM_CLASSID, 1,DMDA);
  PetscValidHeaderSpecific(vec, VEC_CLASSID, 2);
  PetscValidPointer(array, 3);
  if (da->defaultSection) {
    ierr = VecGetArray(vec,(PetscScalar**)array);CHKERRQ(ierr);
    PetscFunctionReturn(0);
  }
  ierr = DMDAGetCorners(da,&xs,&ys,&zs,&xm,&ym,&zm);CHKERRQ(ierr);
  ierr = DMDAGetGhostCorners(da,&gxs,&gys,&gzs,&gxm,&gym,&gzm);CHKERRQ(ierr);
  ierr = DMDAGetInfo(da,&dim,0,0,0,0,0,0,&dof,0,0,0,0,0);CHKERRQ(ierr);

  /* Handle case where user passes in global vector as opposed to local */
  ierr = VecGetLocalSize(vec,&N);CHKERRQ(ierr);
  if (N == xm*ym*zm*dof) {
    gxm = xm;
    gym = ym;
    gzm = zm;
    gxs = xs;
    gys = ys;
    gzs = zs;
  } else if (N != gxm*gym*gzm*dof) SETERRQ3(PETSC_COMM_SELF,PETSC_ERR_ARG_INCOMP,"Vector local size %D is not compatible with DMDA local sizes %D %D\n",N,xm*ym*zm*dof,gxm*gym*gzm*dof);

  if (dim == 1) {
    ierr = VecGetArray1d(vec,gxm*dof,gxs*dof,(PetscScalar**)array);CHKERRQ(ierr);
  } else if (dim == 2) {
    ierr = VecGetArray2d(vec,gym,gxm*dof,gys,gxs*dof,(PetscScalar***)array);CHKERRQ(ierr);
  } else if (dim == 3) {
    ierr = VecGetArray3d(vec,gzm,gym,gxm*dof,gzs,gys,gxs*dof,(PetscScalar****)array);CHKERRQ(ierr);
  } else SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_CORRUPT,"DMDA dimension not 1, 2, or 3, it is %D\n",dim);
  PetscFunctionReturn(0);
}

/*@
   DMDAVecRestoreArray - Restores a multiple dimension array obtained with DMDAVecGetArray()

   Logically collective on da

   Input Parameter:
+  da - the distributed array
.  vec - the vector, either a vector the same size as one obtained with
         DMCreateGlobalVector() or DMCreateLocalVector()
-  array - the array, non-NULL pointer is zeroed

  Level: intermediate

  Fortran Notes:
    From Fortran use DMDAVecRestoreArrayF90()

.seealso: DMDAGetGhostCorners(), DMDAGetCorners(), VecGetArray(), VecRestoreArray(), DMDAVecGetArray()
@*/
PetscErrorCode  DMDAVecRestoreArray(DM da,Vec vec,void *array)
{
  PetscErrorCode ierr;
  PetscInt       xs,ys,zs,xm,ym,zm,gxs,gys,gzs,gxm,gym,gzm,N,dim,dof;

  PetscFunctionBegin;
  PetscValidHeaderSpecificType(da, DM_CLASSID, 1,DMDA);
  PetscValidHeaderSpecific(vec, VEC_CLASSID, 2);
  PetscValidPointer(array, 3);
  if (da->defaultSection) {
    ierr = VecRestoreArray(vec,(PetscScalar**)array);CHKERRQ(ierr);
    PetscFunctionReturn(0);
  }
  ierr = DMDAGetCorners(da,&xs,&ys,&zs,&xm,&ym,&zm);CHKERRQ(ierr);
  ierr = DMDAGetGhostCorners(da,&gxs,&gys,&gzs,&gxm,&gym,&gzm);CHKERRQ(ierr);
  ierr = DMDAGetInfo(da,&dim,0,0,0,0,0,0,&dof,0,0,0,0,0);CHKERRQ(ierr);

  /* Handle case where user passes in global vector as opposed to local */
  ierr = VecGetLocalSize(vec,&N);CHKERRQ(ierr);
  if (N == xm*ym*zm*dof) {
    gxm = xm;
    gym = ym;
    gzm = zm;
    gxs = xs;
    gys = ys;
    gzs = zs;
  } else if (N != gxm*gym*gzm*dof) SETERRQ3(PETSC_COMM_SELF,PETSC_ERR_ARG_INCOMP,"Vector local size %D is not compatible with DMDA local sizes %D %D\n",N,xm*ym*zm*dof,gxm*gym*gzm*dof);

  if (dim == 1) {
    ierr = VecRestoreArray1d(vec,gxm*dof,gxs*dof,(PetscScalar**)array);CHKERRQ(ierr);
  } else if (dim == 2) {
    ierr = VecRestoreArray2d(vec,gym,gxm*dof,gys,gxs*dof,(PetscScalar***)array);CHKERRQ(ierr);
  } else if (dim == 3) {
    ierr = VecRestoreArray3d(vec,gzm,gym,gxm*dof,gzs,gys,gxs*dof,(PetscScalar****)array);CHKERRQ(ierr);
  } else SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_CORRUPT,"DMDA dimension not 1, 2, or 3, it is %D\n",dim);
  PetscFunctionReturn(0);
}

/*@C
   DMDAVecGetArrayDOF - Returns a multiple dimension array that shares data with
      the underlying vector and is indexed using the global dimensions.

   Logically collective

   Input Parameter:
+  da - the distributed array
-  vec - the vector, either a vector the same size as one obtained with
         DMCreateGlobalVector() or DMCreateLocalVector()

   Output Parameter:
.  array - the array

   Notes:
    Call DMDAVecRestoreArrayDOF() once you have finished accessing the vector entries.

    In C, the indexing is "backwards" from what expects: array[k][j][i][DOF] NOT array[i][j][k][DOF]!

    In Fortran 90 you do not need a version of DMDAVecRestoreArrayDOF() just use  DMDAVecRestoreArrayF90() and declare your array with one higher dimension,
    see src/dm/examples/tutorials/ex11f90.F

  Level: intermediate

.seealso: DMDAGetGhostCorners(), DMDAGetCorners(), VecGetArray(), VecRestoreArray(), DMDAVecRestoreArray(), DMDAVecGetArray(), DMDAVecRestoreArrayDOF()
@*/
PetscErrorCode  DMDAVecGetArrayDOF(DM da,Vec vec,void *array)
{
  PetscErrorCode ierr;
  PetscInt       xs,ys,zs,xm,ym,zm,gxs,gys,gzs,gxm,gym,gzm,N,dim,dof;

  PetscFunctionBegin;
  ierr = DMDAGetCorners(da,&xs,&ys,&zs,&xm,&ym,&zm);CHKERRQ(ierr);
  ierr = DMDAGetGhostCorners(da,&gxs,&gys,&gzs,&gxm,&gym,&gzm);CHKERRQ(ierr);
  ierr = DMDAGetInfo(da,&dim,0,0,0,0,0,0,&dof,0,0,0,0,0);CHKERRQ(ierr);

  /* Handle case where user passes in global vector as opposed to local */
  ierr = VecGetLocalSize(vec,&N);CHKERRQ(ierr);
  if (N == xm*ym*zm*dof) {
    gxm = xm;
    gym = ym;
    gzm = zm;
    gxs = xs;
    gys = ys;
    gzs = zs;
  } else if (N != gxm*gym*gzm*dof) SETERRQ3(PETSC_COMM_SELF,PETSC_ERR_ARG_INCOMP,"Vector local size %D is not compatible with DMDA local sizes %D %D\n",N,xm*ym*zm*dof,gxm*gym*gzm*dof);

  if (dim == 1) {
    ierr = VecGetArray2d(vec,gxm,dof,gxs,0,(PetscScalar***)array);CHKERRQ(ierr);
  } else if (dim == 2) {
    ierr = VecGetArray3d(vec,gym,gxm,dof,gys,gxs,0,(PetscScalar****)array);CHKERRQ(ierr);
  } else if (dim == 3) {
    ierr = VecGetArray4d(vec,gzm,gym,gxm,dof,gzs,gys,gxs,0,(PetscScalar*****)array);CHKERRQ(ierr);
  } else SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_CORRUPT,"DMDA dimension not 1, 2, or 3, it is %D\n",dim);
  PetscFunctionReturn(0);
}

/*@
   DMDAVecRestoreArrayDOF - Restores a multiple dimension array obtained with DMDAVecGetArrayDOF()

   Logically collective

   Input Parameter:
+  da - the distributed array
.  vec - the vector, either a vector the same size as one obtained with
         DMCreateGlobalVector() or DMCreateLocalVector()
-  array - the array

  Level: intermediate

.seealso: DMDAGetGhostCorners(), DMDAGetCorners(), VecGetArray(), VecRestoreArray(), DMDAVecGetArray(), DMDAVecGetArrayDOF(), DMDAVecRestoreArrayDOF()
@*/
PetscErrorCode  DMDAVecRestoreArrayDOF(DM da,Vec vec,void *array)
{
  PetscErrorCode ierr;
  PetscInt       xs,ys,zs,xm,ym,zm,gxs,gys,gzs,gxm,gym,gzm,N,dim,dof;

  PetscFunctionBegin;
  ierr = DMDAGetCorners(da,&xs,&ys,&zs,&xm,&ym,&zm);CHKERRQ(ierr);
  ierr = DMDAGetGhostCorners(da,&gxs,&gys,&gzs,&gxm,&gym,&gzm);CHKERRQ(ierr);
  ierr = DMDAGetInfo(da,&dim,0,0,0,0,0,0,&dof,0,0,0,0,0);CHKERRQ(ierr);

  /* Handle case where user passes in global vector as opposed to local */
  ierr = VecGetLocalSize(vec,&N);CHKERRQ(ierr);
  if (N == xm*ym*zm*dof) {
    gxm = xm;
    gym = ym;
    gzm = zm;
    gxs = xs;
    gys = ys;
    gzs = zs;
  }

  if (dim == 1) {
    ierr = VecRestoreArray2d(vec,gxm,dof,gxs,0,(PetscScalar***)array);CHKERRQ(ierr);
  } else if (dim == 2) {
    ierr = VecRestoreArray3d(vec,gym,gxm,dof,gys,gxs,0,(PetscScalar****)array);CHKERRQ(ierr);
  } else if (dim == 3) {
    ierr = VecRestoreArray4d(vec,gzm,gym,gxm,dof,gzs,gys,gxs,0,(PetscScalar*****)array);CHKERRQ(ierr);
  } else SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_CORRUPT,"DMDA dimension not 1, 2, or 3, it is %D\n",dim);
  PetscFunctionReturn(0);
}

/*@C
   DMDAVecGetArrayRead - Returns a multiple dimension array that shares data with
      the underlying vector and is indexed using the global dimensions.

   Not collective

   Input Parameter:
+  da - the distributed array
-  vec - the vector, either a vector the same size as one obtained with DMCreateGlobalVector() or DMCreateLocalVector()

   Output Parameter:
.  array - the array

   Notes:
    Call DMDAVecRestoreArrayRead() once you have finished accessing the vector entries.

    In C, the indexing is "backwards" from what expects: array[k][j][i] NOT array[i][j][k]!

    If vec is a local vector (obtained with DMCreateLocalVector() etc) then the ghost point locations are accessible. If it is
    a global vector then the ghost points are not accessible. Of course with the local vector you will have had to do the

    appropriate DMGlobalToLocalBegin() and DMGlobalToLocalEnd() to have correct values in the ghost locations.

  Fortran Notes:
    From Fortran use DMDAVecGetArrayReadF90() and pass for the array type PetscScalar,pointer :: array(:,...,:) of the appropriate
       dimension. For a DMDA created with a dof of 1 use the dimension of the DMDA, for a DMDA created with a dof greater than 1 use one more than the
       dimension of the DMDA. The order of the indices is array(xs:xs+xm-1,ys:ys+ym-1,zs:zs+zm-1) (when dof is 1) otherwise
       array(0:dof-1,xs:xs+xm-1,ys:ys+ym-1,zs:zs+zm-1) where the values are obtained from
       DMDAGetCorners() for a global array or DMDAGetGhostCorners() for a local array. Include petsc/finclude/petscdmda.h90 to access this routine.

  Due to bugs in the compiler DMDAVecGetArrayReadF90() does not work with gfortran versions before 4.5

  Level: intermediate

.seealso: DMDAGetGhostCorners(), DMDAGetCorners(), VecGetArray(), VecRestoreArray(), DMDAVecRestoreArray(), DMDAVecRestoreArrayDOF()
          DMDAVecGetArrayDOF()
@*/
PetscErrorCode  DMDAVecGetArrayRead(DM da,Vec vec,void *array)
{
  PetscErrorCode ierr;
  PetscInt       xs,ys,zs,xm,ym,zm,gxs,gys,gzs,gxm,gym,gzm,N,dim,dof;

  PetscFunctionBegin;
  PetscValidHeaderSpecificType(da, DM_CLASSID, 1,DMDA);
  PetscValidHeaderSpecific(vec, VEC_CLASSID, 2);
  PetscValidPointer(array, 3);
  if (da->defaultSection) {
    ierr = VecGetArrayRead(vec,(const PetscScalar**)array);CHKERRQ(ierr);
    PetscFunctionReturn(0);
  }
  ierr = DMDAGetCorners(da,&xs,&ys,&zs,&xm,&ym,&zm);CHKERRQ(ierr);
  ierr = DMDAGetGhostCorners(da,&gxs,&gys,&gzs,&gxm,&gym,&gzm);CHKERRQ(ierr);
  ierr = DMDAGetInfo(da,&dim,0,0,0,0,0,0,&dof,0,0,0,0,0);CHKERRQ(ierr);

  /* Handle case where user passes in global vector as opposed to local */
  ierr = VecGetLocalSize(vec,&N);CHKERRQ(ierr);
  if (N == xm*ym*zm*dof) {
    gxm = xm;
    gym = ym;
    gzm = zm;
    gxs = xs;
    gys = ys;
    gzs = zs;
  } else if (N != gxm*gym*gzm*dof) SETERRQ3(PETSC_COMM_SELF,PETSC_ERR_ARG_INCOMP,"Vector local size %D is not compatible with DMDA local sizes %D %D\n",N,xm*ym*zm*dof,gxm*gym*gzm*dof);

  if (dim == 1) {
    ierr = VecGetArray1dRead(vec,gxm*dof,gxs*dof,(PetscScalar**)array);CHKERRQ(ierr);
  } else if (dim == 2) {
    ierr = VecGetArray2dRead(vec,gym,gxm*dof,gys,gxs*dof,(PetscScalar***)array);CHKERRQ(ierr);
  } else if (dim == 3) {
    ierr = VecGetArray3dRead(vec,gzm,gym,gxm*dof,gzs,gys,gxs*dof,(PetscScalar****)array);CHKERRQ(ierr);
  } else SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_CORRUPT,"DMDA dimension not 1, 2, or 3, it is %D\n",dim);
  PetscFunctionReturn(0);
}

/*@
   DMDAVecRestoreArrayRead - Restores a multiple dimension array obtained with DMDAVecGetArrayRead()

   Not collective

   Input Parameter:
+  da - the distributed array
.  vec - the vector, either a vector the same size as one obtained with
         DMCreateGlobalVector() or DMCreateLocalVector()
-  array - the array, non-NULL pointer is zeroed

  Level: intermediate

  Fortran Notes:
    From Fortran use DMDAVecRestoreArrayReadF90()

.seealso: DMDAGetGhostCorners(), DMDAGetCorners(), VecGetArray(), VecRestoreArray(), DMDAVecGetArray()
@*/
PetscErrorCode  DMDAVecRestoreArrayRead(DM da,Vec vec,void *array)
{
  PetscErrorCode ierr;
  PetscInt       xs,ys,zs,xm,ym,zm,gxs,gys,gzs,gxm,gym,gzm,N,dim,dof;

  PetscFunctionBegin;
  PetscValidHeaderSpecificType(da, DM_CLASSID, 1,DMDA);
  PetscValidHeaderSpecific(vec, VEC_CLASSID, 2);
  PetscValidPointer(array, 3);
  if (da->defaultSection) {
    ierr = VecRestoreArrayRead(vec,(const PetscScalar**)array);CHKERRQ(ierr);
    PetscFunctionReturn(0);
  }
  ierr = DMDAGetCorners(da,&xs,&ys,&zs,&xm,&ym,&zm);CHKERRQ(ierr);
  ierr = DMDAGetGhostCorners(da,&gxs,&gys,&gzs,&gxm,&gym,&gzm);CHKERRQ(ierr);
  ierr = DMDAGetInfo(da,&dim,0,0,0,0,0,0,&dof,0,0,0,0,0);CHKERRQ(ierr);

  /* Handle case where user passes in global vector as opposed to local */
  ierr = VecGetLocalSize(vec,&N);CHKERRQ(ierr);
  if (N == xm*ym*zm*dof) {
    gxm = xm;
    gym = ym;
    gzm = zm;
    gxs = xs;
    gys = ys;
    gzs = zs;
  } else if (N != gxm*gym*gzm*dof) SETERRQ3(PETSC_COMM_SELF,PETSC_ERR_ARG_INCOMP,"Vector local size %D is not compatible with DMDA local sizes %D %D\n",N,xm*ym*zm*dof,gxm*gym*gzm*dof);

  if (dim == 1) {
    ierr = VecRestoreArray1dRead(vec,gxm*dof,gxs*dof,(PetscScalar**)array);CHKERRQ(ierr);
  } else if (dim == 2) {
    ierr = VecRestoreArray2dRead(vec,gym,gxm*dof,gys,gxs*dof,(PetscScalar***)array);CHKERRQ(ierr);
  } else if (dim == 3) {
    ierr = VecRestoreArray3dRead(vec,gzm,gym,gxm*dof,gzs,gys,gxs*dof,(PetscScalar****)array);CHKERRQ(ierr);
  } else SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_CORRUPT,"DMDA dimension not 1, 2, or 3, it is %D\n",dim);
  PetscFunctionReturn(0);
}

/*@C
   DMDAVecGetArrayDOFRead - Returns a multiple dimension array that shares data with
      the underlying vector and is indexed using the global dimensions.

   Not Collective

   Input Parameter:
+  da - the distributed array
-  vec - the vector, either a vector the same size as one obtained with
         DMCreateGlobalVector() or DMCreateLocalVector()

   Output Parameter:
.  array - the array

   Notes:
    Call DMDAVecRestoreArrayDOFRead() once you have finished accessing the vector entries.

    In C, the indexing is "backwards" from what expects: array[k][j][i][DOF] NOT array[i][j][k][DOF]!

    In Fortran 90 you do not need a version of DMDAVecRestoreArrayDOF() just use  DMDAVecRestoreArrayReadF90() and declare your array with one higher dimension,
    see src/dm/examples/tutorials/ex11f90.F

  Level: intermediate

.seealso: DMDAGetGhostCorners(), DMDAGetCorners(), VecGetArray(), VecRestoreArray(), DMDAVecRestoreArray(), DMDAVecGetArray(), DMDAVecRestoreArrayDOF()
@*/
PetscErrorCode  DMDAVecGetArrayDOFRead(DM da,Vec vec,void *array)
{
  PetscErrorCode ierr;
  PetscInt       xs,ys,zs,xm,ym,zm,gxs,gys,gzs,gxm,gym,gzm,N,dim,dof;

  PetscFunctionBegin;
  ierr = DMDAGetCorners(da,&xs,&ys,&zs,&xm,&ym,&zm);CHKERRQ(ierr);
  ierr = DMDAGetGhostCorners(da,&gxs,&gys,&gzs,&gxm,&gym,&gzm);CHKERRQ(ierr);
  ierr = DMDAGetInfo(da,&dim,0,0,0,0,0,0,&dof,0,0,0,0,0);CHKERRQ(ierr);

  /* Handle case where user passes in global vector as opposed to local */
  ierr = VecGetLocalSize(vec,&N);CHKERRQ(ierr);
  if (N == xm*ym*zm*dof) {
    gxm = xm;
    gym = ym;
    gzm = zm;
    gxs = xs;
    gys = ys;
    gzs = zs;
  } else if (N != gxm*gym*gzm*dof) SETERRQ3(PETSC_COMM_SELF,PETSC_ERR_ARG_INCOMP,"Vector local size %D is not compatible with DMDA local sizes %D %D\n",N,xm*ym*zm*dof,gxm*gym*gzm*dof);

  if (dim == 1) {
    ierr = VecGetArray2dRead(vec,gxm,dof,gxs,0,(PetscScalar***)array);CHKERRQ(ierr);
  } else if (dim == 2) {
    ierr = VecGetArray3dRead(vec,gym,gxm,dof,gys,gxs,0,(PetscScalar****)array);CHKERRQ(ierr);
  } else if (dim == 3) {
    ierr = VecGetArray4dRead(vec,gzm,gym,gxm,dof,gzs,gys,gxs,0,(PetscScalar*****)array);CHKERRQ(ierr);
  } else SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_CORRUPT,"DMDA dimension not 1, 2, or 3, it is %D\n",dim);
  PetscFunctionReturn(0);
}

/*@
   DMDAVecRestoreArrayDOFRead - Restores a multiple dimension array obtained with DMDAVecGetArrayDOFRead()

   Not Collective

   Input Parameter:
+  da - the distributed array
.  vec - the vector, either a vector the same size as one obtained with
         DMCreateGlobalVector() or DMCreateLocalVector()
-  array - the array

  Level: intermediate

.seealso: DMDAGetGhostCorners(), DMDAGetCorners(), VecGetArray(), VecRestoreArray(), DMDAVecGetArray(), DMDAVecGetArrayDOF(), DMDAVecRestoreArrayDOF()
@*/
PetscErrorCode  DMDAVecRestoreArrayDOFRead(DM da,Vec vec,void *array)
{
  PetscErrorCode ierr;
  PetscInt       xs,ys,zs,xm,ym,zm,gxs,gys,gzs,gxm,gym,gzm,N,dim,dof;

  PetscFunctionBegin;
  ierr = DMDAGetCorners(da,&xs,&ys,&zs,&xm,&ym,&zm);CHKERRQ(ierr);
  ierr = DMDAGetGhostCorners(da,&gxs,&gys,&gzs,&gxm,&gym,&gzm);CHKERRQ(ierr);
  ierr = DMDAGetInfo(da,&dim,0,0,0,0,0,0,&dof,0,0,0,0,0);CHKERRQ(ierr);

  /* Handle case where user passes in global vector as opposed to local */
  ierr = VecGetLocalSize(vec,&N);CHKERRQ(ierr);
  if (N == xm*ym*zm*dof) {
    gxm = xm;
    gym = ym;
    gzm = zm;
    gxs = xs;
    gys = ys;
    gzs = zs;
  }

  if (dim == 1) {
    ierr = VecRestoreArray2dRead(vec,gxm,dof,gxs,0,(PetscScalar***)array);CHKERRQ(ierr);
  } else if (dim == 2) {
    ierr = VecRestoreArray3dRead(vec,gym,gxm,dof,gys,gxs,0,(PetscScalar****)array);CHKERRQ(ierr);
  } else if (dim == 3) {
    ierr = VecRestoreArray4dRead(vec,gzm,gym,gxm,dof,gzs,gys,gxs,0,(PetscScalar*****)array);CHKERRQ(ierr);
  } else SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_CORRUPT,"DMDA dimension not 1, 2, or 3, it is %D\n",dim);
  PetscFunctionReturn(0);
}