C $Header: /u/gcmpack/MITgcm/pkg/ptracers/ptracers_init.F,v 1.11 2005/05/14 22:50:15 jmc Exp $
C $Name:  $

#include "PTRACERS_OPTIONS.h"
#ifdef ALLOW_GCHEM
# include "GCHEM_OPTIONS.h"
#endif

C---+----1----+----2----+----3----+----4----+----5----+----6----+----7-|--+----|
CBOP
C     !ROUTINE: PTRACERS_INIT

C     !INTERFACE:
      SUBROUTINE PTRACERS_INIT( myThid )

C     !DESCRIPTION:
C     Initialize PTRACERS data structures

C     !USES:
      IMPLICIT NONE
#include "SIZE.h"
#include "EEPARAMS.h"
#include "PARAMS.h"
#include "GRID.h"
#include "PTRACERS_SIZE.h"
#include "PTRACERS.h"

C     !INPUT PARAMETERS:
C     myThid               :: thread number
      INTEGER myThid

#ifdef ALLOW_PTRACERS

C     !LOCAL VARIABLES:
C     i,j,k,bi,bj,iTracer  :: loop indices
      INTEGER i,j,k,bi,bj,iTracer
      CHARACTER*(10) suff
CEOP
        
C     Loop over tracers
      DO iTracer = 1, PTRACERS_num

C       Loop over tiles
        DO bj = myByLo(myThid), myByHi(myThid)
          DO bi = myBxLo(myThid), myBxHi(myThid)

C           Initialize arrays in common blocks :
            DO k=1,Nr
              DO j=1-Oly,sNy+OLy
                DO i=1-Olx,sNx+Olx
                  pTracer(i,j,k,bi,bj,iTracer) = 0. _d 0
                  gPtr(i,j,k,bi,bj,iTracer)    = 0. _d 0
                  gPtrNM1(i,j,k,bi,bj,iTracer) = 0. _d 0
                ENDDO
              ENDDO
            ENDDO
            DO j=1-Oly,sNy+OLy
              DO i=1-Olx,sNx+Olx
                surfaceForcingPtr(i,j,bi,bj,iTracer) = 0. _d 0
              ENDDO
            ENDDO

C           end bi,bj loops
          ENDDO
        ENDDO

C       end of Tracer loop
      ENDDO

C     Now read initial conditions and always exchange
      IF (nIter0.EQ.PTRACERS_Iter0) THEN
        DO iTracer = 1, PTRACERS_numInUse
          IF ( PTRACERS_initialFile(iTracer) .NE. ' ' ) THEN
            _BEGIN_MASTER( myThid )
            CALL READ_FLD_XYZ_RL(PTRACERS_initialFile(iTracer),' ',
     &           pTracer(1-Olx,1-Oly,1,1,1,iTracer) ,0,myThid)
            _END_MASTER(myThid)

C           Apply mask
            DO bj = myByLo(myThid), myByHi(myThid)
              DO bi = myBxLo(myThid), myBxHi(myThid)
                DO K=1,Nr
                  DO J=1,sNy
                    DO I=1,sNx
                      IF(hFacC(I,J,K,bi,bj).EQ.0)
     &                     pTracer(i,j,k,bi,bj,iTracer)=0.
                    ENDDO
                  ENDDO
                ENDDO
              ENDDO
            ENDDO

          ELSE
cswdptr -- add ---
cswdptr -- end add ---
          ENDIF
      _EXCH_XYZ_R8(pTracer(1-Olx,1-Oly,1,1,1,iTracer),myThid)
        ENDDO
      ENDIF

C Read from a pickup file if needed
      IF (nIter0.GT.PTRACERS_Iter0) THEN
C       Suffix for pickup files
        IF (pickupSuff.EQ.' ') THEN
          WRITE(suff,'(I10.10)') nIter0
        ELSE
          WRITE(suff,'(A10)') pickupSuff
        ENDIF
        CALL PTRACERS_READ_CHECKPOINT( nIter0,myThid )
      ENDIF

#endif /* ALLOW_PTRACERS */

      RETURN
      END