MPI Collective Communication Routines

MPI_Function	Function Description
MPI_Bcast	Broadcast a message from on process to all others
MPI_Barrier	blocks until all processes have reached this routine
MPI_Reduce	Reduce values from all processes to a single value (add,mult, min, max, etc.)
MPI_Gather	Gathers together values from a group of processes
MPI_Scatter	Sends data from process to the other processes in a group
MPI_Allgather	Gathers data from all tasks and distributes it to all
MPI_Allreduce	Reduces values from all processes and distributes the result back to all processes