MPI_Cart_get.openmpi(3)

Retrieves Cartesian topology information associated with a communicator.

Section 3 openmpi-doc bookworm source

Description

MPI_Cart_get

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.