Newer
Older
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
#include <stdio.h>
#include <mpi.h>
int main(int argc, char **argv)
{
int rank;
int array[8][8];
MPI_Datatype columntype;
int i, j;
MPI_Init(&argc, &argv);
MPI_Comm_rank(MPI_COMM_WORLD, &rank);
// Initialize arrays
if (rank == 0) {
for (i = 0; i < 8; i++) {
for (j = 0; j < 8; j++) {
array[i][j] = (i + 1) * 10 + j + 1;
}
}
} else {
for (i = 0; i < 8; i++) {
for (j = 0; j < 8; j++) {
array[i][j] = 0;
}
}
}
if (rank == 0) {
printf("Data in rank 0\n");
for (i = 0; i < 8; i++) {
for (j = 0; j < 8; j++) {
printf("%3d", array[i][j]);
}
printf("\n");
}
}
//TODO: Create datatype that describes one column. Use MPI_Type_vector.
// Create datatype
MPI_Type_vector(8, 1, 8, MPI_INT, &columntype);
MPI_Type_commit(&columntype);
// Send first column of matrix
if (rank == 0) {
MPI_Send(&array[0][1], 1, columntype, 1, 1, MPI_COMM_WORLD);
} else if (rank == 1) {
MPI_Recv(&array[0][1], 1, columntype, 0, 1, MPI_COMM_WORLD,
MPI_STATUS_IGNORE);
}
// Print out the result
if (rank == 1) {
printf("Received data\n");
for (i = 0; i < 8; i++) {
for (j = 0; j < 8; j++) {
printf("%3d", array[i][j]);
}
printf("\n");
}
}
MPI_Type_free(&columntype);
MPI_Finalize();
return 0;
}