Examples using MPI_ALLGATHER, MPI_ALLGATHERV

  
 
 
The all-gather version of Example Examples using  MPI_GATHER,  MPI_GATHERV
. 
Using  MPI_ALLGATHER, we will gather 100 ints from every process in the 
group to every process. 
 
 
MPI_Comm comm; 
    int gsize,sendarray[100]; 
    int *rbuf; 
    ... 
    MPI_Comm_size( comm, &gsize); 
    rbuf = (int *)malloc(gsize*100*sizeof(int)); 
    MPI_Allgather( sendarray, 100, MPI_INT, rbuf, 100, MPI_INT, comm); 
 
After the call, every process has the group-wide concatenation of the
 
sets of data.