NAME¶
MPI_Graphdims_get - Retrieves graph topology information associated with
a communicator.
SYNTAX¶
C Syntax¶
#include <mpi.h>
int MPI_Graphdims_get(MPI_Comm comm, int *nnodes, int *nedges)
Fortran Syntax¶
INCLUDE 'mpif.h'
MPI_GRAPHDIMS_GET( COMM, NNODES, NEDGES, IERROR)
INTEGER COMM, NNODES, NEDGES, IERROR
C++ Syntax¶
#include <mpi.h>
void Graphcomm::Get dims(int nnodes[], int nedges[]) const
- comm
- Communicator for group with graph structure (handle).
OUTPUT PARAMETERS¶
- nnodes
- Number of nodes in graph (integer).
- nedges
- Number of edges in graph (integer).
- IERROR
- Fortran only: Error status (integer).
DESCRIPTION¶
Functions MPI_Graphdims_get and MPI_Graph_get retrieve the graph-topology
information that was associated with a communicator by MPI_Graph_create.
The information provided by MPI_Graphdims_get can be used to dimension the
vectors index and edges correctly for a call to MPI_Graph_get.
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_create
MPI_Graph_get
