mp_cart_sub Subroutine

   SUBROUTINE mp_cart_sub(comm, rdim, sub_comm)

      INTEGER, INTENT(IN)                                :: comm
      LOGICAL, DIMENSION(:), CONTIGUOUS, INTENT(IN)      :: rdim
      INTEGER, INTENT(OUT)                               :: sub_comm

      CHARACTER(LEN=*), PARAMETER :: routineN = 'mp_cart_sub'

      INTEGER                                            :: handle, ierr

      ierr = 0
      CALL timeset(routineN, handle)

      sub_comm = 0
#if defined(__parallel)
      CALL mpi_cart_sub(comm, rdim, sub_comm, ierr)
      IF (ierr /= 0) CALL mp_stop(ierr, "mpi_cart_sub @ "//routineN)
      debug_comm_count = debug_comm_count + 1
#else
      MARK_USED(comm)
      MARK_USED(rdim)
#endif
      CALL timestop(handle)

   END SUBROUTINE mp_cart_sub