next up previous contents
Next: MPIINITIALIZED MPI Initialized Test Up: MPI Functions Previous: MPIALLREDUCE MPI All Reduce   Contents

Subsections

MPIREDUCE MPI Reduce Operation

Usage

This function implements the reduction operation using MPI. The general syntax for its use is

   x = mpireduce(y,operation,root,comm)

where y is the current processes contribution to the reduction operation, operation is either '+','*','>','<' for an additive, multiplicative, max or min type reduction operations respectively, root is the rank of the process that will retrieve the result of the reduction operation, and comm is the MPI communicator handle. If no communicator is provided, then MPI_COMM_WORLD is used by default. Note that FreeMat does not check to ensure that the reduction operation y arguments are all the same size across the various processes in the group. Instead, you must make sure that each process passes the same sized array to the mpireduce operation.



Samit K. Basu 2005-03-16