Creates an intracommunicator from an intercommunicator
mpi.intercomm.merge(intercomm=2, high=0, comm=1)an intercommunicator number
Used to order the groups of the two intracommunicators within comm when creating the new communicator
a (intra)communicator number
1 if success. Otherwise 0.
When master spawns slaves, an intercommunicator is created. To make
communications (point-to-point or groupwise) among master and slaves, an
intracommunicator must be created. mpi.intercomm.merge is used for
that purpose. This is a collective call so all master and slaves call
together. R slaves spawned by mpi.spawn.Rslaves should use
mpi.comm.get.parent to get (set) an intercomm to a number followed
by merging antercomm to an intracomm. One
can use mpi.comm.test.inter to test if a
communicator is an intercommunicator or not.