17.2.36. MPI_Cart_get

MPI_Cart_get - Retrieves Cartesian topology information associated with a communicator.

17.2.36.1. Syntax

17.2.36.1.1. C Syntax

#include <mpi.h>

int MPI_Cart_get(MPI_Comm comm, int maxdims, int dims[], int periods[],
    int coords[])

17.2.36.1.2. 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(*)

17.2.36.1.3. 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

17.2.36.2. Input Parameters

  • comm : Communicator with Cartesian structure (handle).

  • maxdims : Length of vectors dims, periods, and coords in the calling program (integer).

17.2.36.3. 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).

17.2.36.4. 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.

17.2.36.5. 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_Cartdim_get