mpi_graph_neighbors_count(3)
NAME
MPI_Graph_neighbors_count - Returns the number of neighbors of a node
associated with a graph topology.
SYNTAX
C Syntax
- #include <mpi.h>
int MPI_Graph_neighbors_count(MPI_Comm comm, int rank, - int *nneighbors)
Fortran Syntax
- INCLUDE 'mpif.h'
MPI_GRAPH_NEIGHBORS_COUNT(COMM, RANK, NNEIGHBORS, IERROR) - INTEGER COMM, RANK, NNEIGHBORS, IERROR
C++ Syntax
#include <mpi.h>
int Graphcomm::Get_neighbors_count(int rank) const
INPUT PARAMETERS
comm Communicator with graph topology (handle).
rank Rank of process in group of comm (integer).
OUTPUT PARAMETERS
- nneighbors
- Number of neighbors of specified process (integer).
- IERROR Fortran only: Error status (integer).
DESCRIPTION
MPI_Graph_neighbors_count and MPI_Graph_neighbors provide adjacency
information for a general, graph topology. MPI_Graph_neighbors_count
returns the number of neighbors for the process signified by rank.
ERRORS
Almost all MPI routines return an error value; C routines as the value
of the function and Fortran routines in the last argument. C++ functions do not return errors. If the default error handler is set to
MPI::ERRORS_THROW_EXCEPTIONS, then on error the C++ exception mechanism
will be used to throw an MPI:Exception object.
Before the error value is returned, the current MPI error handler is
called. By default, this error handler aborts the MPI job, except for
I/O function errors. The error handler may be changed with
MPI_Comm_set_errhandler; the predefined error handler MPI_ERRORS_RETURN
may be used to cause error values to be returned. Note that MPI does
not guarantee that an MPI program can continue past an error.
SEE ALSO
- MPI_Graph_neighbors