NAME

MPI_Cart_get - Retrieves Cartesian topology information associated with a communicator.

SYNTAX

C Syntax

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

Fortran Syntax

USE MPI
! or the older form: INCLUDE 'mpif.h'
MPI_CART_GET(COMM, MAXDIMS, DIMS, PERIODS, COORDS, IERROR)
	INTEGER	COMM, MAXDIMS, DIMS(*), COORDS(*), IERROR
	LOGICAL	PERIODS(*)

Fortran 2008 Syntax

USE mpi_f08
MPI_Cart_get(comm, maxdims, dims, periods, coords, ierror)
	TYPE(MPI_Comm), INTENT(IN) :: comm
	INTEGER, INTENT(IN) :: maxdims
	INTEGER, INTENT(OUT) :: dims(maxdims), coords(maxdims)
	LOGICAL, INTENT(OUT) :: periods(maxdims)
	INTEGER, OPTIONAL, INTENT(OUT) :: ierror

C++ Syntax

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

INPUT PARAMETERS

comm: Communicator with Cartesian structure (handle).
maxdims: Length of vectors dims, periods, and coords in the calling program (integer).

OUTPUT PARAMETERS

dims: Number of processes for each Cartesian dimension (array of integers).
periods: Periodicity (true/false) for each Cartesian dimension (array of logicals).
coords: Coordinates of calling process in Cartesian structure (array of integers).
IERROR: Fortran only: Error status (integer).

DESCRIPTION

The functions MPI_Cartdim_get and MPI_Cart_get return the Cartesian topology information that was associated with a communicator by MPI_Cart_create.

ERRORS

Almost all MPI routines return an error value; C routines as the value of the function and Fortran routines in the last argument. C++ functions do not return errors. If the default error handler is set to MPI::ERRORS_THROW_EXCEPTIONS, then on error the C++ exception mechanism will be used to throw an MPI::Exception object.

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.