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/* This example sends a vector and receives individual elements */
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int main( int argc, char **argv )
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double *vecin, *vecout, ivalue;
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int root, i, n, stride, err = 0;
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MPI_Init( &argc, &argv );
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MPI_Comm_size( MPI_COMM_WORLD, &size );
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MPI_Comm_rank( MPI_COMM_WORLD, &rank );
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vecin = (double *)malloc( n * stride * size * sizeof(double) );
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vecout = (double *)malloc( n * sizeof(double) );
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MPI_Type_vector( n, 1, stride, MPI_DOUBLE, &vec );
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MPI_Type_commit( &vec );
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for (i=0; i<n*stride*size; i++) vecin[i] = (double)i;
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for (root=0; root<size; root++) {
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for (i=0; i<n; i++) vecout[i] = -1.0;
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MPI_Scatter( vecin, 1, vec, vecout, n, MPI_DOUBLE, root,
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ivalue = rank * ((n-1) * stride + 1);
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if (vecout[i] != ivalue) {
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printf( "Expected %f but found %f\n",
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MPI_Allreduce( &i, &err, 1, MPI_INT, MPI_SUM, MPI_COMM_WORLD );
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if (err > 0) printf( "Found %d errors!\n", err );
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else printf( " No Errors\n" );
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MPI_Type_free( &vec );