sayhello.c

C语言编写的并行计算柏松矩阵

#include "mpi.h"
#include <stdio.h>
#include <stdlib.h>
void Hello( void );
int main(int argc, char *argv[])
    {
        int me, option, namelen, size;
        char processor_name[MPI_MAX_PROCESSOR_NAME];
        MPI_Init(&argc, &argv);
        MPI_Comm_rank(MPI_COMM_WORLD,&me);
        MPI_Comm_size(MPI_COMM_WORLD,&size);
        if (size < 2) {
            fprintf(stderr, "systest requires at least 2 processes" );
            MPI_Abort(MPI_COMM_WORLD,1);
        }
        MPI_Get_processor_name(processor_name,&namelen);
        fprintf(stderr,"Process %d is alive on %s\n", me, processor_name);
        MPI_Barrier(MPI_COMM_WORLD);
        Hello();
        MPI_Finalize();
}
void Hello( void )
    {
        int nproc, me;
        int type = 1;
        int buffer[2], node;
        MPI_Status status;
        MPI_Comm_rank(MPI_COMM_WORLD, &me);
        MPI_Comm_size(MPI_COMM_WORLD, &nproc);
        if (me == 0) {
        printf("\nHello test from all to all\n");
        fflush(stdout);
        }
        for (node = 0; node<nproc; node++) {
            if (node != me) {
            buffer[0] = me;
            buffer[1] = node;
            MPI_Send(buffer, 2, MPI_INT, node, type, MPI_COMM_WORLD);
            MPI_Recv(buffer, 2, MPI_INT, node, type, MPI_COMM_WORLD, &status);
            if ( (buffer[0] != node) || (buffer[1] != me) ) {
                (void) fprintf(stderr, "Hello: %d!=%d or %d!=%d\n", buffer[0], node, buffer[1], me);
                printf("Mismatch on hello process ids; node = %d\n", node);
            }
            printf("Hello from %d to %d\n", me, node);
            fflush(stdout);
        }
    }
}