Nonblocking Gather

7.12.3. Nonblocking Gather

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MPI_IGATHER(sendbuf, sendcount, sendtype, recvbuf, recvcount, recvtype, root, comm, 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)
OUT request	communication request (handle)

C binding
int MPI_Igather(const void *sendbuf, int sendcount, MPI_Datatype sendtype, void *recvbuf, int recvcount, MPI_Datatype recvtype, int root, MPI_Comm comm, MPI_Request *request) int MPI_Igather_c(const void *sendbuf, MPI_Count sendcount, MPI_Datatype sendtype, void *recvbuf, MPI_Count recvcount, MPI_Datatype recvtype, int root, MPI_Comm comm, MPI_Request *request) Fortran 2008 binding
MPI_Igather(sendbuf, sendcount, sendtype, recvbuf, recvcount, recvtype, root, comm, request, ierror) TYPE(*), DIMENSION(..), INTENT(IN), ASYNCHRONOUS :: sendbuf INTEGER, INTENT(IN) :: sendcount, recvcount, root TYPE(MPI_Datatype), INTENT(IN) :: sendtype, recvtype TYPE(*), DIMENSION(..), ASYNCHRONOUS :: recvbuf TYPE(MPI_Comm), INTENT(IN) :: comm TYPE(MPI_Request), INTENT(OUT) :: request INTEGER, OPTIONAL, INTENT(OUT) :: ierror MPI_Igather(sendbuf, sendcount, sendtype, recvbuf, recvcount, recvtype, root, comm, request, ierror) !(_c) TYPE(*), DIMENSION(..), INTENT(IN), ASYNCHRONOUS :: sendbuf INTEGER(KIND=MPI_COUNT_KIND), INTENT(IN) :: sendcount, recvcount TYPE(MPI_Datatype), INTENT(IN) :: sendtype, recvtype TYPE(*), DIMENSION(..), ASYNCHRONOUS :: recvbuf INTEGER, INTENT(IN) :: root TYPE(MPI_Comm), INTENT(IN) :: comm TYPE(MPI_Request), INTENT(OUT) :: request INTEGER, OPTIONAL, INTENT(OUT) :: ierror Fortran binding
MPI_IGATHER(SENDBUF, SENDCOUNT, SENDTYPE, RECVBUF, RECVCOUNT, RECVTYPE, ROOT, COMM, REQUEST, IERROR) <type> SENDBUF(*), RECVBUF(*) INTEGER SENDCOUNT, SENDTYPE, RECVCOUNT, RECVTYPE, ROOT, COMM, REQUEST, IERROR

This call starts a nonblocking variant of MPI_GATHER (see Section Gather).

MPI_IGATHERV(sendbuf, sendcount, sendtype, recvbuf, recvcounts, displs, recvtype, root, comm, 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)
OUT request	communication request (handle)

C binding
int MPI_Igatherv(const void *sendbuf, int sendcount, MPI_Datatype sendtype, void *recvbuf, const int recvcounts[], const int displs[], MPI_Datatype recvtype, int root, MPI_Comm comm, MPI_Request *request) int MPI_Igatherv_c(const void *sendbuf, MPI_Count sendcount, MPI_Datatype sendtype, void *recvbuf, const MPI_Count recvcounts[], const MPI_Aint displs[], MPI_Datatype recvtype, int root, MPI_Comm comm, MPI_Request *request) Fortran 2008 binding
MPI_Igatherv(sendbuf, sendcount, sendtype, recvbuf, recvcounts, displs, recvtype, root, comm, request, ierror) TYPE(*), DIMENSION(..), INTENT(IN), ASYNCHRONOUS :: sendbuf INTEGER, INTENT(IN) :: sendcount, root TYPE(MPI_Datatype), INTENT(IN) :: sendtype, recvtype TYPE(*), DIMENSION(..), ASYNCHRONOUS :: recvbuf INTEGER, INTENT(IN), ASYNCHRONOUS :: recvcounts(*), displs(*) TYPE(MPI_Comm), INTENT(IN) :: comm TYPE(MPI_Request), INTENT(OUT) :: request INTEGER, OPTIONAL, INTENT(OUT) :: ierror MPI_Igatherv(sendbuf, sendcount, sendtype, recvbuf, recvcounts, displs, recvtype, root, comm, request, ierror) !(_c) TYPE(*), DIMENSION(..), INTENT(IN), ASYNCHRONOUS :: sendbuf INTEGER(KIND=MPI_COUNT_KIND), INTENT(IN) :: sendcount TYPE(MPI_Datatype), INTENT(IN) :: sendtype, recvtype TYPE(*), DIMENSION(..), ASYNCHRONOUS :: recvbuf INTEGER(KIND=MPI_COUNT_KIND), INTENT(IN), ASYNCHRONOUS :: recvcounts(*) INTEGER(KIND=MPI_ADDRESS_KIND), INTENT(IN), ASYNCHRONOUS :: displs(*) INTEGER, INTENT(IN) :: root TYPE(MPI_Comm), INTENT(IN) :: comm TYPE(MPI_Request), INTENT(OUT) :: request INTEGER, OPTIONAL, INTENT(OUT) :: ierror Fortran binding
MPI_IGATHERV(SENDBUF, SENDCOUNT, SENDTYPE, RECVBUF, RECVCOUNTS, DISPLS, RECVTYPE, ROOT, COMM, REQUEST, IERROR) <type> SENDBUF(*), RECVBUF(*) INTEGER SENDCOUNT, SENDTYPE, RECVCOUNTS(*), DISPLS(*), RECVTYPE, ROOT, COMM, REQUEST, IERROR

This call starts a nonblocking variant of MPI_GATHERV (see Section Gather).

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