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/*
* Copyright (C) by Argonne National Laboratory
* See COPYRIGHT in top-level directory
*/
#include "mpi.h"
#include <stdio.h>
#include "mpitest.h"
#define MAX_PROCESSES 10
int main(int argc, char **argv)
{
int rank, size, i, j;
int table[MAX_PROCESSES][MAX_PROCESSES];
int row[MAX_PROCESSES];
int errors = 0;
int participants;
int displs[MAX_PROCESSES];
int send_counts[MAX_PROCESSES];
MTest_Init(&argc, &argv);
MPI_Comm_rank(MPI_COMM_WORLD, &rank);
MPI_Comm_size(MPI_COMM_WORLD, &size);
/* A maximum of MAX_PROCESSES processes can participate */
if (size > MAX_PROCESSES)
participants = MAX_PROCESSES;
else
participants = size;
if ((rank < participants)) {
int recv_count = MAX_PROCESSES;
/* If I'm the root (process 0), then fill out the big table */
/* and setup send_counts and displs arrays */
if (rank == 0)
for (i = 0; i < participants; i++) {
send_counts[i] = recv_count;
displs[i] = i * MAX_PROCESSES;
for (j = 0; j < MAX_PROCESSES; j++)
table[i][j] = i + j;
}
/* Scatter the big table to everybody's little table */
MPI_Scatterv(&table[0][0], send_counts, displs, MPI_INT,
&row[0], recv_count, MPI_INT, 0, MPI_COMM_WORLD);
/* Now see if our row looks right */
for (i = 0; i < MAX_PROCESSES; i++)
if (row[i] != i + rank)
errors++;
}
MTest_Finalize(errors);
return MTestReturnValue(errors);
}
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