MPI_ALLTOALLV(3)MPI_ALLTOALLV(3)NAMEMPI_Alltoallv - Sends data from all processes to all processes, with a
displacement
SYNOPSIS
C:
#include <mpi.h>
int MPI_Alltoallv ( sendbuf, sendcnts, sdispls, sendtype,
recvbuf, recvcnts, rdispls, recvtype, comm )
void *sendbuf;
int *sendcnts;
int *sdispls;
MPI_Datatype sendtype;
void *recvbuf;
Cint *recvcnts;
int *rdispls;
MPI_Datatype recvtype;
MPI_Comm comm;
C++:
#include <mpi.h>
void Intracomm::Alltoallv(
const void* sendbuf,
const int sendcounts[],
const int sdispls[],
const Datatype& sendtype,
void* recvbuf,
const int recvcounts[],
const int rdispls[],
const Datatype& recvtype) const
Fortran:
INCLUDE "mpif.h" (or USE MPI)
<type> SENDBUF(*), RECVBUF(*)
INTEGER sendcounts(*), sdispls(*), sendtype,
recvcounts(*), rdispls(*), recvtype, comm,
ierror
CALL MPI_ALLTOALLV(sendbuf, sendcounts(*), sdispls(*),
sendtype, recvbuf, recvcounts(*), rdispls(*),
recvtype, comm, ierror)
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MPI_ALLTOALLV(3)MPI_ALLTOALLV(3)STANDARDS
This release implements the MPI 1.2 standard, as documented by the MPI
Forum in the spring 1997 release of MPI: A Message Passing Interface
Standard.
DESCRIPTION
The MPI_Alltoallv routine sends data from all processes to all processes,
with a displacement. This routine accepts the following parameters:
sendbuf Specifies the starting address of the send buffer
(choice).
sendcnts Specifies an integer array equal to the group size,
specified in comm, indicating the number of elements to
send to each processor.
sdispls Specifies an integer array equal to the group size,
specified in comm. Entry j specifies the displacement
(relative to sendbuf) from which to take the outgoing data
destined for process j.
sendtype Specifies the data type of the send buffer elements
(handle).
recvcnts Specifies the maximum number of elements that can be
received from each processor.
rdispls Specifies an integer array equal to the group size,
specified in comm. Entry i specifies the displacement
(relative to recvbuf) at which to place the incoming data
from process i.
recvtype Specifies the data type of the receive buffer elements
(handle).
comm Specifies the communicator (handle).
recvbuf Returns the address of the receive buffer (choice).
ierror Specifies the return code value for successful completion,
which is in MPI_SUCCESS. MPI_SUCCESS is defined in the
mpif.h file.
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