C -*- Mode: Fortran; -*- 

C

C (C) 2005 by Argonne National Laboratory.

C     See COPYRIGHT in top-level directory.

C

C This is a simple test that Fortran support the MPI_IN_PLACE value

C

       program main

       implicit none

       include 'mpif.h'

       integer ierr, errs

       integer comm, root

       integer rank, size

       integer i

       integer MAX_SIZE

       parameter (MAX_SIZE=1024)

       integer rbuf(MAX_SIZE), rdispls(MAX_SIZE), rcount(MAX_SIZE),

     $      sbuf(MAX_SIZE) 

       errs = 0

       call mtest_init( ierr )

       comm = MPI_COMM_WORLD

       call mpi_comm_rank( comm, rank, ierr )

       call mpi_comm_size( comm, size, ierr )

       root = 0

C Gather with inplace

       do i=1,size

          rbuf(i) = - i

       enddo

       rbuf(1+root) = root

       if (rank .eq. root) then

          call mpi_gather( MPI_IN_PLACE, 1, MPI_INTEGER, rbuf, 1,

     $         MPI_INTEGER, root, comm, ierr )

          do i=1,size

             if (rbuf(i) .ne. i-1) then

                errs = errs + 1

                print *, '[',rank,'] rbuf(', i, ') = ', rbuf(i), 

     $                   ' in gather'  

             endif

          enddo

       else

          call mpi_gather( rank, 1, MPI_INTEGER, rbuf, 1, MPI_INTEGER,

     $         root, comm, ierr )

       endif   

C Gatherv with inplace

       do i=1,size

          rbuf(i) = - i

          rcount(i) = 1

          rdispls(i) = i-1

       enddo

       rbuf(1+root) = root

       if (rank .eq. root) then

          call mpi_gatherv( MPI_IN_PLACE, 1, MPI_INTEGER, rbuf, rcount,

     $         rdispls, MPI_INTEGER, root, comm, ierr )

          do i=1,size

             if (rbuf(i) .ne. i-1) then

                errs = errs + 1

                print *, '[', rank, '] rbuf(', i, ') = ', rbuf(i), 

     $                ' in gatherv'

             endif

          enddo

       else

          call mpi_gatherv( rank, 1, MPI_INTEGER, rbuf, rcount, rdispls,

     $         MPI_INTEGER, root, comm, ierr )

       endif   

C Scatter with inplace

       do i=1,size

          sbuf(i) = i

       enddo

       rbuf(1) = -1

       if (rank .eq. root) then

          call mpi_scatter( sbuf, 1, MPI_INTEGER, MPI_IN_PLACE, 1,

     $         MPI_INTEGER, root, comm, ierr )

       else

          call mpi_scatter( sbuf, 1, MPI_INTEGER, rbuf, 1,

     $         MPI_INTEGER, root, comm, ierr )

          if (rbuf(1) .ne. rank+1) then

             errs = errs + 1

             print *, '[', rank, '] rbuf  = ', rbuf(1),

     $            ' in scatter' 

          endif

       endif   

       call mtest_finalize( errs )

       call mpi_finalize( ierr )

       end