MPI Subroutine Reference

MPI_CART_GET, MPI_Cart_get

Purpose

Retrieves cartesian topology information from a communicator.

C synopsis

#include <mpi.h>
MPI_Cart_get(MPI_Comm comm,int maxdims,int *dims,int *periods,int *coords);

C++ synopsis

#include mpi.h
void MPI::Cartcomm::Get_topo(int maxdims, int dims[], 
			     bool periods[], int coords[]) const;

FORTRAN synopsis

include 'mpif.h' or use mpi
MPI_CART_GET(INTEGER COMM,INTEGER MAXDIMS,INTEGER DIMS(*),
	     INTEGER PERIODS(*),INTEGER COORDS(*),INTEGER IERROR)

Parameters

comm

is a communicator with cartesian topology (handle) (IN)

maxdims

is the length of dims, periods, and coords in the calling program (integer) (IN)

dims

is the number of tasks for each cartesian dimension (array of integer) (OUT)

periods

is a logical array specifying if each cartesian dimension is periodic or not. (OUT)

coords

is the coordinates of the calling task in the cartesian structure (array of integer) (OUT)

IERROR

is the FORTRAN return code. It is always the last argument.

Description

This subroutine retrieves the cartesian topology information associated with a communicator in dims, periods and coords.

Errors

MPI not initialized

MPI already finalized

Invalid communicator

No topology

Invalid topology type

must be cartesian

Invalid array size

maxdims < 0

Related information

MPI_CART_CREATE

MPI_CARTDIM_GET