Loadable Function: [RANK INFO] = MPI_Comm_size (COMM)

Return the size of a communicator. The comunicator object COMM (loaded with MPI_Comm_Load) must be sepcified or otherwise an error occurs.

             exprank rank of the calling process in group of communicator
             exprinfo (int) return code
                0 MPI_SUCCESS    No error
                5 MPI_ERR_COMM   Invalid communicator (NULL?)
               13 MPI_ERR_ARG    Invalid argument (typically a NULL pointer?)
          SEE ALSO: MPI_Comm_rank