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/*
* Copyright (C) by Argonne National Laboratory
* See COPYRIGHT in top-level directory
*/
#include "mpi.h"
#include "mpitest.h"
#include <stdlib.h>
#include <stdio.h>
/* This example sends a vector and receives individual elements, but the
root process does not receive any data */
int main(int argc, char **argv)
{
MPI_Datatype vec;
double *vecin, *vecout, ivalue;
int root, i, n, stride, errs = 0;
int rank, size;
MPI_Aint vextent, tmp_lb;
MTest_Init(&argc, &argv);
MPI_Comm_size(MPI_COMM_WORLD, &size);
MPI_Comm_rank(MPI_COMM_WORLD, &rank);
n = 12;
stride = 10;
vecin = (double *) malloc(n * stride * size * sizeof(double));
vecout = (double *) malloc(n * sizeof(double));
MPI_Type_vector(n, 1, stride, MPI_DOUBLE, &vec);
MPI_Type_commit(&vec);
MPI_Type_get_extent(vec, &tmp_lb, &vextent);
if (vextent != ((n - 1) * (MPI_Aint) stride + 1) * sizeof(double)) {
errs++;
printf("Vector extent is %ld, should be %ld\n",
(long) vextent, (long) (((n - 1) * stride + 1) * sizeof(double)));
}
/* Note that the exted of type vector is from the first to the
* last element, not n*stride.
* E.g., with n=1, the extent is a single double */
for (i = 0; i < n * stride * size; i++)
vecin[i] = (double) i;
for (root = 0; root < size; root++) {
for (i = 0; i < n; i++)
vecout[i] = -1.0;
if (rank == root) {
MPI_Scatter(vecin, 1, vec, MPI_IN_PLACE, -1, MPI_DATATYPE_NULL, root, MPI_COMM_WORLD);
} else {
MPI_Scatter(NULL, -1, MPI_DATATYPE_NULL, vecout, n, MPI_DOUBLE, root, MPI_COMM_WORLD);
ivalue = rank * ((n - 1) * stride + 1);
for (i = 0; i < n; i++) {
if (vecout[i] != ivalue) {
printf("[%d] Expected %f but found %f for vecout[%d]\n",
rank, ivalue, vecout[i], i);
errs++;
}
ivalue += stride;
}
}
}
free(vecin);
free(vecout);
MPI_Type_free(&vec);
MTest_Finalize(errs);
return MTestReturnValue(errs);
}
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