next up previous contents
Next: Motivating Examples Up: Groups, Contexts and Communicators Previous: Group Management   Contents

Communicator Management

int Comm.size()
returns: number of processors in the group of this communicator



Size of group of this communicator. Java binding of the MPI operation MPI_COMM_SIZE.

int Comm.rank()
returns: rank of the calling process in the group of this communicator



Rank of this process in group of this communicator. Java binding of the MPI operation MPI_COMM_RANK.

static int Comm.compare(Comm comm1, Comm comm2)
comm1 first communicator
comm2 second communicator
   
returns: result



Compare two communicators. Java binding of the MPI operation MPI_COMM_COMPARE. MPI.IDENT results if the comm1 and comm2 are references to the same object (ie, if comm1 == comm2). MPI.CONGRUENT results if the underlying groups are identical but the communicators differ by context. MPI.SIMILAR results if the underlying groups are similar but the communicators differ by context. MPI.UNEQUAL results otherwise.

Object Comm.clone()
returns: copy of this communicator



Duplicate this communicator. Java binding of the MPI operation MPI_COMM_DUP. The new communicator is ``congruent'' to the old one, but has a different context.

Intracomm Intracomm.create(Group group)
group group which is a subset of the group of this communicator
   
returns: new communicator



Create a new communicator. Java binding of the MPI operation MPI_COMM_CREATE.

Intracomm Intracomm.split(int color, int key)
color control of subset assignment
key control of rank assignment
   
returns: new communicator



Partition the group associated with this communicator and create a new communicator within each subgroup. Java binding of the MPI operation MPI_COMM_SPLIT.

void Comm.free()
Destroy this communicator. Java binding of the MPI operation MPI_COMM_FREE.


next up previous contents
Next: Motivating Examples Up: Groups, Contexts and Communicators Previous: Group Management   Contents
Bryan Carpenter 2002-07-12