MPI_INTERCOMM_MERGE(3)MPI_INTERCOMM_MERGE(3)NAMEMPI_Intercomm_merge - Creates an intracommuncator from an
intercommunicator
SYNOPSIS
C:
#include <mpi.h>
int MPI_Intercomm_merge ( comm, high, comm_out )
MPI_Comm comm;
int high;
MPI_Comm *comm_out;
C++:
#include <mpi.h>
Intracomm Intercomm::Merge(
bool high) const
Fortran:
INCLUDE "mpif.h" (or USE MPI)
INTEGER intercomm, intracomm, ierror
LOGICAL high
CALL MPI_INTERCOMM_MERGE(intercomm, high, intracomm, ierror)
STANDARDS
This release implements the MPI 1.2 standard, as documented by the MPI
Forum in the spring 1997 release of MPI: A Message Passing Interface
Standard.
DESCRIPTION
The MPI_Intercomm_merge routine creates an intracommuncator from an
intercommunicator. This routine accepts the following parameters:
comm Specifies the intercommunicator
high Specifies a value used to order the groups of the two
intracommunicators within comm when creating the new
communicator
comm_out Returns the created intracommunicator
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MPI_INTERCOMM_MERGE(3)MPI_INTERCOMM_MERGE(3)
ierror Specifies the return code value for successful completion,
which is in MPI_SUCCESS. MPI_SUCCESS is defined in the mpif.h
file.
NOTES
The following algorithm is used to create the intracommunicator:
1. Allocate two contexts.
2. Swap high values between local and remote group leaders.
3. Determine the high value.
4. Merge the two groups and make the intracommunicator.
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