MPI_Dist_graph_create_adjacent

returns a handle to a new communicator to which the distributed graph topology information is attached.

Synopsis

int MPI_Dist_graph_create_adjacent(MPI_Comm comm_old,
                                   int indegree, const int sources[],
                                   const int sourceweights[],
                                   int outdegree, const int destinations[],
                                   const int destweights[],
                                   MPI_Info info, int reorder, MPI_Comm *comm_dist_graph)

Input Parameters

comm_old: input communicator (handle)
indegree: size of sources and sourceweights arrays (non-negative integer)
sources: ranks of processes for which the calling process is a destination (array of non-negative integers)
sourceweights: weights of the edges into the calling process (array of non-negative integers or MPI_UNWEIGHTED)
outdegree: size of destinations and destweights arrays (non-negative integer)
destinations: ranks of processes for which the calling process is a source (array of non-negative integers)
destweights: weights of the edges out of the calling process (array of non-negative integers or MPI_UNWEIGHTED)
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 (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 mallocor 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. ierris 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 INTEGERin 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_ARG: Invalid argument. Some argument is invalid and is not identified by a specific error class (e.g., MPI_ERR_RANK).

MPI_ERR_OTHER: Other error; use MPI_Error_string to get more information about this error code.