MPI_SCAN( sendbuf, recvbuf, count, datatype, op, comm ) | |
IN sendbuf | starting address of send buffer (choice) |
OUT recvbuf | starting address of receive buffer (choice) |
IN count | number of elements in input buffer (non-negative integer) |
IN datatype | data type of elements of input buffer (handle) |
IN op | operation (handle) |
IN comm | communicator (handle) |
int MPI_Scan(void* sendbuf, void* recvbuf, int count, MPI_Datatype datatype, MPI_Op op, MPI_Comm comm )
MPI_SCAN(SENDBUF, RECVBUF, COUNT, DATATYPE, OP, COMM, IERROR)
<type> SENDBUF(*), RECVBUF(*)
INTEGER COUNT, DATATYPE, OP, COMM, IERROR
void MPI::Intracomm::Scan(const void* sendbuf, void* recvbuf, int count, const MPI::Datatype& datatype, const MPI::Op& op) const
If comm is an intracommunicator,
MPI_SCAN is used to perform a prefix reduction
on data distributed across the group.
The operation returns, in the receive buffer of the process with rank
i, the
reduction of the values in the send buffers of processes with ranks
0,...,i (inclusive). The type of operations supported,
their semantics, and the
constraints on send and receive buffers are as for MPI_REDUCE.
The ``in place'' option for intracommunicators is specified by passing
MPI_IN_PLACE
in the sendbuf argument. In this case, the input data is
taken from the receive buffer, and replaced by the output data.
This operation is invalid for intercommunicators.