| MPI_GATHER_INIT(sendbuf, sendcount, sendtype, recvbuf, recvcount, recvtype, root, comm, info, request) | |
| IN sendbuf | starting address of send buffer (choice) |
| IN sendcount | number of elements in send buffer (nonnegative integer) |
| IN sendtype | datatype of send buffer elements (handle) |
| OUT recvbuf | address of receive buffer (choice, significant only at root) |
| IN recvcount | number of elements for any single receive (nonnegative integer, significant only at root) |
| IN recvtype | datatype of recv buffer elements (handle, significant only at root) |
| IN root | rank of receiving MPI process (integer) |
| IN comm | communicator (handle) |
| IN info | info argument (handle) |
| OUT request | communication request (handle) |
Creates a persistent collective communication request for the gather operation (see Section Gather).
| MPI_GATHERV_INIT(sendbuf, sendcount, sendtype, recvbuf, recvcounts, displs, recvtype, root, comm, info, request) | |
| IN sendbuf | starting address of send buffer (choice) |
| IN sendcount | number of elements in send buffer (nonnegative integer) |
| IN sendtype | datatype of send buffer elements (handle) |
| OUT recvbuf | address of receive buffer (choice, significant only at root) |
| IN recvcounts | nonnegative integer array (of length group size) containing the number of elements that are received from each MPI process (significant only at root) |
| IN displs | integer array (of length group size). Entry i specifies the displacement relative to recvbuf at which to place the incoming data from MPI process i (significant only at root) |
| IN recvtype | datatype of recv buffer elements (handle, significant only at root) |
| IN root | rank of receiving MPI process (integer) |
| IN comm | communicator (handle) |
| IN info | info argument (handle) |
| OUT request | communication request (handle) |
Creates a persistent collective communication request for the gatherv operation (see Section Gather).