PROGRAM MPIexample_pack
   IMPLICIT NONE
   INCLUDE "mpif.h"

   REAL(8), DIMENSION(2) :: SWV  = 0.0
   INTEGER :: XYdots  =  0 
   INTEGER :: Niter  = 1000
   
   REAL(8) :: Range = 0.0 
   REAL ::   tempo2, tempo1, tempro

  
!  MPI variables
   CHARACTER(MPI_MAX_PROCESSOR_NAME) :: server
   INTEGER :: ierr, pos, my_rank, numprocs, ls
   CHARACTER(32) :: pckd_data
!
   call MPI_INIT( ierr )
   call MPI_COMM_RANK( MPI_COMM_WORLD, my_rank, ierr )
   call MPI_COMM_SIZE( MPI_COMM_WORLD, numprocs, ierr )
   call MPI_Get_processor_name(server,ls,ierr)
!
   SWV = [0.0,1.0]
   XYdots  =  101
   Range = 1.0
   Niter  = 1000     


   IF ( my_rank == 0 ) THEN
   	   ! Master process looks for input data
      CALL CPU_TIME(tempo1)

       Pos = 0
       CALL MPI_PACK (SWV, 2, MPI_DOUBLE_PRECISION, &
       &           pckd_data, 32, pos, MPI_COMM_WORLD, ierr)
       CALL MPI_PACK (XYdots, 1, MPI_INTEGER, &
       &           pckd_data, 32, pos, MPI_COMM_WORLD, ierr)
       CALL MPI_PACK (Range, 1, MPI_DOUBLE_PRECISION, &
       &           pckd_data, 32, pos, MPI_COMM_WORLD, ierr)
       CALL MPI_PACK (NITER, 1, MPI_INTEGER, &
       &           pckd_data, 32, pos, MPI_COMM_WORLD, ierr)
       print*,"Data sent: ",SWV,XYdots,Range,NITER
    ENDIF

    CALL MPI_BCAST (pckd_data, 32, MPI_PACKED , 0, &
       &       MPI_COMM_WORLD, ierr)

    IF ( my_rank /= 0 ) THEN
       Pos = 0
       CALL MPI_UNPACK (pckd_data, 32, pos, SWV, 2, MPI_DOUBLE_PRECISION, &
       &           MPI_COMM_WORLD, ierr)
       CALL MPI_UNPACK (pckd_data, 32, pos, XYdots, 1, MPI_INTEGER, &
       &           MPI_COMM_WORLD, ierr)
       CALL MPI_UNPACK (pckd_data, 32, pos, Range, 1, MPI_DOUBLE_PRECISION, &
       &           MPI_COMM_WORLD, ierr)
       CALL MPI_UNPACK (pckd_data, 32, pos, NITER, 1, MPI_INTEGER, &
       &           MPI_COMM_WORLD, ierr)
       print*,"Data rcvd: ",SWV,XYdots,Range,NITER
    ENDIF

   CALL CPU_TIME(tempo2)
   
   tempro =  (tempo2 - tempo1)

   WRITE(*,*) "CPU time is ",tempro

   CALL MPI_BARRIER(MPI_COMM_WORLD,ierr)
   CALL Terminate(my_rank)
   STOP
END PROGRAM MPIexample_pack

SUBROUTINE Terminate(p)
   IMPLICIT NONE
   INTEGER, INTENT(IN) :: P
   INCLUDE "mpif.h"
   INTEGER :: ierr
   
   WRITE(*,*) "Process ",p," terminates"
   CALL MPI_Finalize(ierr)
   
   STOP
END SUBROUTINE Terminate