Ndtyjky

I was trying to install and run MS-MPI following this tutorial. I have installed MS-MPI and all my system variables are set correctly, see:

I have set all links in VS

Having these linked to the project, I would expect MPI to work. In IDE no syntax errors are shown, MPI functions are recognized, just as in next picture. However compiling an c++ source file with MPI functions produces Undeclared identifiers errors. What do I do wrong?

Here is my code if it matters

    /*

    * Transmit a message in a 3-process system.

    */

    #include <mpi.h>

    #include "stdafx.h"

    #include <stdio.h>

    #include <stdlib.h>



    #define BUFSIZE 10

    int main(int argc, char *argv)

    { int size, rank;

    int slave;

    int buf[BUFSIZE];

    int n, value;

    float rval;

    MPI_Status status;

    /* Initialize MPI  */

    MPI_Init(&argc, &argv);

    /*

    * Determine size in the world group.

    */

    MPI_Comm_size(MPI_COMM_WORLD, &size);

    if (size == 3) {/* Correct number of processes *}

                    /*

                    * Determine my rank in the world group.

                    * The master will be rank 0 and the slaves, rank 1...size-1

                    */



        MPI_Comm_rank(MPI_COMM_WORLD, &rank);



        if (rank == 0) { /* Master */

            buf[0] = 5; buf[1] = 1; buf[2] = 8; buf[3] = 7; buf[4] = 6;

            buf[5] = 5; buf[6] = 4; buf[7] = 2; buf[8] = 3; buf[9] = 1;

            printf("n Sending the values {5,1,8,7,6,5,4,2,3,1}");

            printf("n -----------------------------");

            for (slave = 1; slave < size; slave++) {

                printf("n from master %d to slave %d", rank, slave);

                MPI_Send(buf, 10, MPI_INT, slave, 1, MPI_COMM_WORLD);

            }

            printf("nn Receiving the results from slaves");

            printf("n ---------------------------------");

            MPI_Recv(&value, 1, MPI_INT, 1, 11, MPI_COMM_WORLD, &status);

            printf("n Minimum %4d from slave 1", value);

            MPI_Recv(&value, 1, MPI_INT, 2, 21, MPI_COMM_WORLD, &status);

            printf("n Sum     %4d from slave 2", value);

            MPI_Recv(&value, 1, MPI_INT, 1, 12, MPI_COMM_WORLD, &status);

            printf("n Maximum %4d from slave 1", value);

            MPI_Recv(&rval, 1, MPI_FLOAT, 2, 22, MPI_COMM_WORLD, &status);

            printf("n Average %4.2f from slave 2n", rval);

        }

        else {

            if (rank == 1) { /* minmax slave */

                MPI_Recv(buf, 10, MPI_INT, 0, 1, MPI_COMM_WORLD, &status);

                value = 100;

                for (n = 0; n<BUFSIZE; n++) {

                    if (value>buf[n]) { value = buf[n]; }

                }

                MPI_Send(&value, 1, MPI_INT, 0, 11, MPI_COMM_WORLD);

                value = 0;

                for (n = 0; n<BUFSIZE; n++) {

                    if (value<buf[n]) { value = buf[n]; }

                }

                MPI_Send(&value, 1, MPI_INT, 0, 12, MPI_COMM_WORLD);

            }

            else { /* sumave slave */

                MPI_Recv(buf, 10, MPI_INT, 0, 1, MPI_COMM_WORLD, &status);

                value = 0;

                for (n = 0; n<BUFSIZE; n++) {

                    value = value + buf[n];

                }

                MPI_Send(&value, 1, MPI_INT, 0, 21, MPI_COMM_WORLD);

                rval = (float)value / BUFSIZE;

                MPI_Send(&rval, 1, MPI_FLOAT, 0, 22, MPI_COMM_WORLD);

            }

        }

    }

    MPI_Finalize();

    return(0);

    }

After a time I have found where was the bug. Everything is fine with my setting, problem is only with the .cpp extension. Changing it to .c project helped and all works as expected.

If I want to run it as c++, #include stdafx.h bust take place before mpi