MPI_Gather

int MPI_Gather(void* , int, MPI_Datatype, void*, int, MPI_Datatype, int, MPI_Comm); int MPI_Gatherv(void* , int, MPI_Datatype, void*, int *, int *, MPI_Datatype, int, MPI_Comm);int MPI_Scatter(void* , int, MPI_Datatype, void*, int, MPI_Datatype, int, MPI_Comm);
Collects individual messages from each task in a group at the root task.