NAME

       MPI_Dist_graph_create  -   MPI_DIST_GRAPH_CREATE returns a handle to a new communicator to
       which the distributed graph topology information is attached

SYNOPSIS

       int MPI_Dist_graph_create(MPI_Comm comm_old, int n, const int sources[], const int degrees[],
       const int destinations[], const int weights[], MPI_Info info, int reorder,
       MPI_Comm *comm_dist_graph)

INPUT PARAMETERS

       comm_old
              - input communicator (handle)
       n      - number of source nodes for  which  this  process  specifies  edges  (non-negative
              integer)
       sources
              -  array  containing  the  n  source nodes for + which this process specifies edges
              (non-negative integer)
       degrees
              - array specifying the number of destinations for each source node  in  the  source
              node array (non-negative integer)
       destinations
              -  destination  nodes  for  the source nodes in the source node array (non-negative
              integer)
       weights
              - weights for source to destination edges (non-negative integer)
       info   - hints on optimization and interpretation of weights (handle)
       reorder
              - the ranks may be reordered (true) or not~(false) (logical)

OUTPUT PARAMETERS

       comm_dist_graph
              - communicator with distributed graph topology added (handle)

THREAD AND INTERRUPT SAFETY

       This routine is thread-safe.  This means that this routine may be safely used by  multiple
       threads  without the need for any user-provided thread locks.  However, the routine is not
       interrupt safe.  Typically, this is due to the use of memory allocation routines  such  as
       malloc or other non-MPICH runtime routines that are themselves not interrupt-safe.

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  guarantee 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_ARG
              - Invalid argument.  Some argument is invalid and is not identified by  a  specific
              error class (e.g., MPI_ERR_RANK ).
       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_INFO
              - Invalid Info
       MPI_ERR_OTHER
              - Other error; use MPI_Error_string to get more information about this error code.

                                            2/22/2022                    MPI_Dist_graph_create(3)