Myujth

I have two threads (rank 0 and 1), each containing a 3D matrix (x0,y,z) and (x1,y,z) with a different size along the x dimension. I would like to send a specific plane (x0 constant,y,z) from the first thread to the second and replace one of its face (x1 constant, y, z). The following code I made seems to work well when the two matrices have identical dimensions (even in x), but does not send the right face when x0 != x1 :

double ***alloc2(int x, int y,int z)

 int i, j;

 double ***array = (double ***) malloc(sizeof(double ***)*x);
 for (i = 0; i<x; i++)
 array[i] = (double **) malloc(sizeof(double*)*y);
 for (j=0; j<y; j++)
 array[i][j] = (double *) malloc(sizeof(double)*z);

 return array;



int main(int argc, char *argv)

MPI_Status status;
MPI_Comm_size(MPI_COMM_WORLD, &nbr);
MPI_Comm_rank(MPI_COMM_WORLD, &rank);

/* Some long code I skiped */
/* ... */

MPI_Datatype sub;
MPI_Type_vector(nL+1, nL+1, nL_thread, MPI_DOUBLE, &sub);
MPI_Type_commit(&sub);

if(rank == 0)
 MPI_Send(&c_new[3][0][0], 1, sub, rank+1,01, MPI_COMM_WORLD);
 MPI_Recv(&c_new[4][0][0], 1, sub, rank+1,10, MPI_COMM_WORLD, &status);
if(rank == 1)
 MPI_Recv(&c_new[0][0][0], 1, sub, rank-1,01, MPI_COMM_WORLD, &status);
 MPI_Send(&c_new[1][0][0], 1, sub, rank-1,10, MPI_COMM_WORLD);

nL is the length in the y and z dimensions, same for all threads, nL_thread is the x dimension (in this particular case, nL_thread = 3 for rank 1 and 4 for rank 0). here I am trying to replace the faces (0,y,z) of rank 1 by (3,y,z) of rank 0, and (4,y,z) of rank 0 by (1,y,z) of rank 1.