Manpages - MPI_Dist_graph_neighbors_count.3

Table of Contents

NAME

*MPI_Dist_graph_neighbors_count * - Returns the number of in and out edges for the calling processes in a distributed graph topology and a flag indicating whether the distributed graph is weighted.

SYNTAX

C Syntax

  #include <mpi.h>
  int MPI_Dist_graph_neighbors_count(MPI_Comm comm, int *indegree,
  	int *outdegree, int *weighted)

Fortran Syntax

  USE MPI
  ! or the older form: INCLUDE 'mpif.h'
  MPI_DIST_GRAPH_NEIGHBORS_COUNT(COMM, INDEGREE, OUTDEGREE, WEIGHTED, IERROR)
  	INTEGER	COMM, INDEGREE, OUTDEGREE, IERROR
          LOGICAL WEIGHTED

Fortran 2008 Syntax

  USE mpi_f08
  MPI_Dist_graph_neighbors_count(comm, indegree, outdegree, weighted, ierror)
  	TYPE(MPI_Comm), INTENT(IN) :: comm
  	INTEGER, INTENT(IN) :: indegree, outdegree
  	INTEGER, INTENT(OUT) :: weighted
  	INTEGER, OPTIONAL, INTENT(OUT) :: ierror

INPUT PARAMETERS

comm
Communicator with distributed graph topology (handle).

OUTPUT PARAMETERS

indegree
Number of edges into this process (non-negative integer).
outdegree
Number of edges out of this process (non-negative integer).
weighted
False if MPI_UNWEIGHTED was supplied during creation, true otherwise (logical).
IERROR
Fortran only: Error status (integer).

DESCRIPTION

MPI_Dist_graph_neighbors_count and MPI_Graph_neighbors provide adjacency information for a distributed graph topology. MPI_Dist_graph_neighbors_count returns the number of sources and destinations for the calling process.

ERRORS

Almost all MPI routines return an error value; C routines as the value of the function and Fortran routines in the last argument.

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_Dist_graph_neighbors

Author: dt

Created: 2022-02-20 Sun 17:00