MODULE zpermute
   !!=====================================================================
   !!                    ***  MODULE  zpermute ***
   !! Manipulate array :  Library to read input files
   !!====================================================================
   !! History :  3.3.1  ! 2011 11  (S. Pickles) Original code
   !!
   !!--------------------------------------------------------------------
   !!   permute_z_last : return pointer to a copy of an array with indices
   !!                    permuted back to z_last ordering
   !!--------------------------------------------------------------------
   USE par_oce, ONLY : wp                   ! ocean parameters - working precision
   USE lib_mpp, ONLY : ctl_warn, ctl_stop   ! warning and fatal messages

   IMPLICIT NONE
   PRIVATE

   PUBLIC permute_z_last

   !!----------------------------------------------------------------------
   !! NEMO/OPA 3.3 , NEMO Consortium (2011)
   !! $Id$
   !! Software governed by the CeCILL licence (NEMOGCM/NEMO_CeCILL.txt)
   !!----------------------------------------------------------------------

CONTAINS

   FUNCTION permute_z_last( pain )   RESULT ( p_permuted )

      !!----------------------------------------------------------------------
      !!                     ***  ROUTINE permute_z_last  ***
      !!
      !! ** Purpose :   
      !!
      !!----------------------------------------------------------------------

      REAL(wp), INTENT(in) :: pain(:,:,:)

      REAL(wp), ALLOCATABLE, SAVE, DIMENSION(:,:,:), TARGET :: pain_reordered 
      REAL(wp), POINTER, DIMENSION(:,:,:)                   :: p_permuted
 
      INTEGER, SAVE :: jiss=-1, jjss=-1, jkss=-1
      INTEGER       :: jisz,    jjsz,    jksz
      INTEGER       :: ji,      jj,      jk
      INTEGER       :: ifail

#if defined key_z_first
      jisz = SIZE(pain, DIM=2)
      jjsz = SIZE(pain, DIM=3)
      jksz = SIZE(pain, DIM=1)
#else
      jisz = SIZE(pain, DIM=1)
      jjsz = SIZE(pain, DIM=2)
      jksz = SIZE(pain, DIM=3)
#endif

      IF ( (jiss /= jisz) .OR. (jjss /= jjsz) .OR. (jkss /= jksz)) THEN
         IF (ALLOCATED(pain_reordered)) THEN
            DEALLOCATE(pain_reordered)
         END IF 
      ELSE
         IF (.NOT. ALLOCATED(pain_reordered)) THEN
            CALL ctl_warn("permute_z_last: unexpected need to allocate array")
         END IF
      END IF

      IF (.NOT. ALLOCATED(pain_reordered)) THEN
         ALLOCATE(pain_reordered(jisz,jjsz,jksz), STAT=ifail)
         IF (ifail /= 0) THEN
            CALL ctl_stop("permute_z_last: failure allocating output array")
         END IF 
      END IF

      DO jk = 1, jksz
         DO jj = 1, jjsz
            DO ji = 1, jisz
!FTRANS pain :I :I :z
               pain_reordered(ji, jj, jk) = pain(ji, jj, jk)
            END DO
         END DO
      END DO

      jiss = jisz
      jjss = jjsz
      jkss = jksz
      p_permuted => pain_reordered

   END FUNCTION permute_z_last

   !!======================================================================
END MODULE zpermute