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Exercise/Example: Translate this Fortran http://siber.cankaya.edu.tr/ParallelComputing/cfiles/sendreceive.fcode to C

      program main
      include 'mpif.h'

      integer rank, size, to, from, tag, count, i, ierr
      integer src, dest
      integer st_source, st_tag, st_count
      integer status(MPI_STATUS_SIZE)
      double precision data(100)

      call MPI_INIT( ierr )
      call MPI_COMM_RANK( MPI_COMM_WORLD, rank, ierr )
      call MPI_COMM_SIZE( MPI_COMM_WORLD, size, ierr )
      print *, 'Process ', rank, ' of ', size, ' is alive'
      dest = size - 1
      src = 0
C      
      if (rank .eq. src) then
         to     = dest
         count  = 10
         tag    = 2001
         do 10 i=1, 10
 10         data(i) = i
         call MPI_SEND( data, count, MPI_DOUBLE_PRECISION, to,
     +                   tag, MPI_COMM_WORLD, ierr )
      else if (rank .eq. dest) then
         tag   = MPI_ANY_TAG
         count = 10		
         from  = MPI_ANY_SOURCE
         call MPI_RECV(data, count, MPI_DOUBLE_PRECISION, from,
     +                  tag, MPI_COMM_WORLD, status, ierr ) 
         call MPI_GET_COUNT( status, MPI_DOUBLE_PRECISION, 
     +                       st_count, ierr )
         st_source = status(MPI_SOURCE)
         st_tag    = status(MPI_TAG)
C         
         print *, 'Status info: source = ', st_source, 
     +             ' tag = ', st_tag, ' count = ', st_count
         print *, rank, ' received', (data(i),i=1,10)
      endif
        
      call MPI_FINALIZE( ierr )
      end



Cem Ozdogan 2006-12-27