C $Header: /home/ubuntu/mnt/e9_copy/MITgcm_contrib/nesting_sannino/nest_child/nest_eeinit.F,v 1.1 2010/11/28 00:50:11 jmc Exp $
C $Name:  $

#include "NEST_CHILD_OPTIONS.h"

CBOP
C     !ROUTINE: NEST_EEINIT

C     !INTERFACE:
      SUBROUTINE NEST_EEINIT(
     I                        mpiMyWid,
     O                        color )

C     !DESCRIPTION:
C     *==========================================================*
C     | SUBROUTINE NEST\_EEINIT
C     | o Set Nesting Execution Environment
C     *==========================================================*
C     | This is the NEST_CHILD  version
C     *==========================================================*

C     !USES:
      IMPLICIT NONE
C     == Global data ==
#include "SIZE.h"
#include "EEPARAMS.h"
#include "EESUPPORT.h"
#include "NEST_CHILD_PARAMS.h"

C     !INPUT PARAMETERS:
C     mpiMyWid      :: my World MPI rank
      INTEGER mpiMyWid

C     !OUTPUT PARAMETERS:
C     color         :: type of group I belong to
      INTEGER color

#ifdef ALLOW_USE_MPI
C     !LOCAL VARIABLES:
C     mpiRC         :: Error code reporting variable used with MPI.
C     msgBuf        :: Used to build messages for printing.
c     CHARACTER*(MAX_LEN_MBUF) msgBuf
      INTEGER mpiRC
      INTEGER size, npd
      INTEGER Count_Lev
CEOP

C---+----1----+----2----+----3----+----4----+----5----+----6----+----7-|--+----|

       CALL MPI_COMM_SIZE( MPI_COMM_WORLD, size, mpiRC )
       npd=size-(NCPUs_PAR_C+NCPUs_CLD_C(1))

       MSTR_DRV_C(1) = 0
       MSTR_PAR_C(1) = npd
       MSTR_CLD_C(1) = NCPUs_PAR_C + npd

       DO Count_Lev = 2, NST_LEV_TOT_C
         MSTR_DRV_C(Count_Lev) = MSTR_CLD_C(Count_Lev-1)
     &                         + NCPUs_CLD_C(Count_Lev-1)
         MSTR_CLD_C(Count_Lev) = MSTR_DRV_C(Count_Lev) + 1
         MSTR_PAR_C(Count_Lev) = MSTR_CLD_C(Count_Lev-1)
       ENDDO

       IF (NST_LEV_C.EQ.1) THEN
         IF (mpiMyWId.GE.MSTR_PAR_C(1).AND.mpiMyWId.LT.MSTR_CLD_C(1))
     &          color = 1
         IF (mpiMyWId.GE.MSTR_CLD_C(1))
     &          color = 2
       ENDIF

       IF (NST_LEV_C.GT.1) THEN
         IF (mpiMyWId.GE.MSTR_CLD_C(NST_LEV_C).AND.
     &       mpiMyWId.LT.MSTR_CLD_C(NST_LEV_C)+NCPUs_CLD_C(NST_LEV_C))
     &          color = (NST_LEV_C + 1)
       ENDIF

C--   split per group of same color ?
       CALL MPI_COMM_SPLIT ( MPI_COMM_WORLD, color, 0,
     &                       MPI_COMM_MODEL, mpiRC )
       IF ( mpiRC .NE. MPI_SUCCESS ) THEN
         write(*,*) 'error SPLIT'
       ENDIF

#else /* ALLOW_USE_MPI */
      STOP 'ABNORMAL END: S/R NEST_EEINIT: Needs to Use MPI'
#endif /* ALLOW_USE_MPI */

C---+----1----+----2----+----3----+----4----+----5----+----6----+----7-|--+----|

      RETURN
      END