MPI_INTERCOMM_MERGE, MPI_Intercomm_merge

Purpose

Creates an intracommunicator by merging the local and remote groups of an
intercommunicator.

C synopsis

#include <mpi.h>
int MPI_Intercomm_merge(MPI_Comm intercomm,int high,
                        MPI_Comm *newintracomm);

C++ synopsis

#include mpi.h
MPI::Intracomm MPI::Intercomm::Merge(bool high);

FORTRAN synopsis

include 'mpif.h' or use mpi
MPI_INTERCOMM_MERGE(INTEGER INTERCOMM,INTEGER HIGH,
                    INTEGER NEWINTRACOMM,INTEGER IERROR)

Parameters

intercomm
     is the intercommunicator (handle) (IN)

high
     (logical) (IN)

newintracomm
     is the new intracommunicator (handle) (OUT)

IERROR
     is the FORTRAN return code. It is always the last argument.

Description

This subroutine creates an intracommunicator from the union of two groups
associated with intercomm. Tasks should provide the same high value within
each of the two groups. If tasks in one group provide the value
high = false and tasks in the other group provide the value high = true,
the union orders the "low" group before the "high" group. If all tasks
provided the same high argument, the order of the union is arbitrary.
MPI_INTERCOMM_MERGE is blocking and collective within the union of the two
groups.

Errors

Invalid communicator

Invalid communicator type
     must be intercommunicator

Inconsistent high within group

MPI not initialized

MPI already finalized

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