mp_prod_c Subroutine

private subroutine mp_prod_c(msg, gid)

Multiplies a set of numbers scattered across a number of processes, then replicates the result.

MPI mapping mpi_allreduce

Arguments

TypeIntentOptionalAttributesName
complex(kind=real_4), intent(inout) :: msg

a number to multiply (input) and result (output)

integer, intent(in) :: gid

message passing environment identifier


Contents

Source Code


Source Code

      SUBROUTINE mp_prod_c (msg, gid)
      !! Multiplies a set of numbers scattered across a number of processes,
      !! then replicates the result.
      !!
      !! MPI mapping
      !! mpi_allreduce

         COMPLEX(kind=real_4), INTENT(INOUT)                 :: msg
         !! a number to multiply (input) and result (output)
         INTEGER, INTENT(IN)                      :: gid
         !! message passing environment identifier

         CHARACTER(LEN=*), PARAMETER :: routineN = 'mp_sum_c'

         INTEGER                                  :: handle, ierr, msglen

         ierr = 0
         CALL timeset(routineN, handle)

         msglen = 1
#if defined(__parallel)
         CALL mpi_allreduce(MPI_IN_PLACE, msg, msglen, MPI_COMPLEX, MPI_PROD, gid, ierr)
         IF (ierr /= 0) CALL mp_stop(ierr, "mpi_allreduce @ "//routineN)
         CALL add_perf(perf_id=3, msg_size=msglen*(2*real_4_size))
#else
         MARK_USED(msg)
         MARK_USED(gid)
#endif
         CALL timestop(handle)
      END SUBROUTINE mp_prod_c