Hi

when i execute this program (I use two processes) i have a error in the display part :

* RESULT OF EXECUTION:

0 1 2 3 4 5 6 7 8 9

>> (1,6) << 

>>>>

> 1 <

* -6277438562204192500000000000000000000000000000000000000000000000000 * -6277438562204192500000000000000000000000000000000000000000000000000 * -6277438562204192500000000000000000000000000000000000000000000000000 * -6277438562204192500000000000000000000000000000000000000000000000000 * -6277438562204192500000000000000000000000000000000000000000000000000 * -6277438562204192500000000000000000000000000000000000000000000000000

0 1 2 3 4 5 6 7 8 9

0  1  2  3  

4  5  6  7  8  9  

>> (0,4) << 

>>>>

> 0 <

* 0 * 1 * 2 * 3 

* PROGRAM

#include <malloc.h>

#include <stdlib.h>

#include <stdio.h>

#include <time.h>

#include "math.h"

#include "mpi.h"

int main(int argc, char** argv)

{

int          taskid, ntasks;

int          ierr, i, itask;

int          sendcounts[2048], displs[2048], recvcount;

double       **sendbuff, *recvbuff, buffsum, buffsums[2048];

double       inittime, totaltime;

const int nbr_etat = 10;

double tab[nbr_etat];

for (int i = 0; i < nbr_etat; i++)

tab[i] = i;

for (int i = 0; i < nbr_etat; i++)

printf("%0.0f ", tab[i]);

printf("\n");

int nbr_elm[2] = { 4, 6 };

int dpl[2] = { 0, 4 };

MPI_Init(&argc, &argv);

MPI_Comm_rank(MPI_COMM_WORLD, &taskid);

MPI_Comm_size(MPI_COMM_WORLD, &ntasks);

recvbuff = (double *)malloc(sizeof(double)*nbr_etat);

if (taskid == 0)

{

sendbuff = (double **)malloc(sizeof(double *)*ntasks);// on execute pour deux proc

sendbuff[0] = (double *)malloc(sizeof(double)*ntasks*nbr_etat);

for (i = 1; i < ntasks; i++)

{

sendbuff[i] = sendbuff[i - 1] + nbr_etat;

}

}

else

{

sendbuff = (double **)malloc(sizeof(double *)* 1);

sendbuff[0] = (double *)malloc(sizeof(double)* 1);

}

if (taskid == 0){

srand((unsigned)time(NULL) + taskid);

for (itask = 0; itask<ntasks; itask++)

{

int k;

displs[itask] = dpl[itask];

int s = displs[itask];

sendcounts[itask] = nbr_elm[itask];

for (i = 0; i<sendcounts[itask]; i++)

{

k = i + s;

sendbuff[itask][i] = tab[k];

printf("%0.0f  ", sendbuff[itask][i]);

}

printf("\n");

}

}

recvcount = nbr_elm[taskid];

inittime = MPI_Wtime();

ierr = MPI_Scatterv(sendbuff[0], sendcounts, displs, MPI_DOUBLE,

recvbuff, recvcount, MPI_DOUBLE,

0, MPI_COMM_WORLD);

totaltime = MPI_Wtime() - inittime;

                            

printf("\n >>>> \n");

buffsum = 0.0;

printf("\n > %d < \n",taskid);

for (i = 0; i<recvcount; i++)

{

printf("* %0.0f ", recvbuff[i]);

}

printf("\n");                                  

if (taskid == 0){

free(sendbuff[0]);

free(sendbuff);

}

else{

free(sendbuff[0]);

free(sendbuff);

free(recvbuff);

}

/*===============================================================*/

/* Finalisation de MPI                                           */

MPI_Finalize();

}