NAME

       MPI_Graph_get -  Retrieves graph topology information associated with a  communicator

SYNOPSIS

       int MPI_Graph_get(MPI_Comm comm, int maxindex, int maxedges,
                         int indx[], int edges[])

INPUT PARAMETERS

       comm   - communicator with graph structure (handle)
       maxindex
              - length of vector indx in the calling program  (integer)
       maxedges
              - length of vector edges in the calling program  (integer)

OUTPUT PARAMETERS

       indx   -  array of integers containing the graph structure (for details see the definition
              of MPI_GRAPH_CREATE )
       edges  - array of integers containing the graph structure

THREAD AND INTERRUPT SAFETY

       This routine is both thread- and interrupt-safe.  This means that this routine may  safely
       be used by multiple threads and from within a signal handler.

NOTES FOR FORTRAN

       All  MPI  routines  in  Fortran  (except  for MPI_WTIME and MPI_WTICK ) have an additional
       argument ierr at the end of the argument list.  ierr  is  an  integer  and  has  the  same
       meaning  as  the  return  value  of  the  routine  in  C.   In  Fortran,  MPI routines are
       subroutines, and are invoked with the call statement.

       All MPI objects (e.g., MPI_Datatype , MPI_Comm ) are of type INTEGER in Fortran.

ERRORS

       All MPI routines (except MPI_Wtime and MPI_Wtick ) return an error value;  C  routines  as
       the  value of the function and Fortran routines in the last argument.  Before the value is
       returned, the current MPI error handler is called.  By default, this error handler  aborts
       the  MPI  job.   The  error  handler  may  be  changed  with  MPI_Comm_set_errhandler (for
       communicators), MPI_File_set_errhandler (for files), and MPI_Win_set_errhandler  (for  RMA
       windows).   The  MPI-1  routine  MPI_Errhandler_set may be used but its use is deprecated.
       The predefined error handler MPI_ERRORS_RETURN may be used to cause  error  values  to  be
       returned.   Note  that  MPI  does  not  guarentee that an MPI program can continue past an
       error; however, MPI implementations will attempt to continue whenever possible.

       MPI_SUCCESS
              - No error; MPI routine completed successfully.
       MPI_ERR_TOPOLOGY
              - Invalid topology.  Either there is no topology associated with this communicator,
              or it is not the correct type (e.g., MPI_CART when expecting MPI_GRAPH ).
       MPI_ERR_COMM
              -  Invalid  communicator.   A  common error is to use a null communicator in a call
              (not even allowed in MPI_Comm_rank ).
       MPI_ERR_ARG
              - Invalid argument.  Some argument is invalid and is not identified by  a  specific
              error class (e.g., MPI_ERR_RANK ).

                                            11/12/2016                           MPI_Graph_get(3)