debian man page for mpi_graph_create

MPI_Graph_create(3)							MPI						       MPI_Graph_create(3)

NAME
       MPI_Graph_create -  Makes a new communicator to which topology information has been attached

SYNOPSIS
       int MPI_Graph_create(MPI_Comm comm_old, int nnodes, int *indx, int *edges,
			   int reorder, MPI_Comm *comm_graph)

INPUT PARAMETERS
       comm_old
	      - input communicator without topology (handle)
       nnodes - number of nodes in graph (integer)
       indx   - array of integers describing node degrees (see below)
       edges  - array of integers describing graph edges (see below)
       reorder
	      - ranking may be reordered (true) or not (false) (logical)

OUTPUT PARAMETER
       comm_graph
	      - communicator with graph topology added (handle)

NOTES
       Each process must provide a description of the entire graph, not just the neigbors of the calling process.

ALGORITHM
       We ignore the reorder info currently.

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 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 ).

LOCATION
       graphcreate.c

								     8/31/2010						       MPI_Graph_create(3)