MPI_Reduce(3)              (10/24/1994)             MPI_Reduce(3)



     NAME
          MPI_Reduce - Reduces values on all processes to a single
          value


     INPUT PARAMETERS
          sendbuf
               - address of send buffer (choice)
          count
               - number of elements in send buffer (integer)
          datatype
               - data type of elements of send buffer (handle)
          op   - reduce operation (handle)
          root - rank of root process (integer)
          comm - communicator (handle)


     OUTPUT PARAMETER
          recvbuf
               - address of receive buffer (choice, significant only
               at root)


     ALGORITHM
          This implementation currently uses a simple tree algorithm.


     SYNOPSIS
          #include "mpi.h"
          int MPI_Reduce ( sendbuf, recvbuf, count, datatype, op, root, comm )
          void             *sendbuf;
          void             *recvbuf;
          int               count;
          MPI_Datatype      datatype;
          MPI_Op            op;
          int               root;
          MPI_Comm          comm;



     LOCATION
           reduce.c













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