:ref:`MPI_Cart_map` - Maps process to Cartesian topology information.
#include <mpi.h>
int MPI_Cart_map(MPI_Comm comm, int ndims, const int dims[],
const int periods[], int *newrank)
USE MPI
! or the older form: INCLUDE 'mpif.h'
MPI_CART_MAP(COMM, NDIMS, DIMS, PERIODS, NEWRANK, IERROR)
INTEGER COMM, NDIMS, DIMS(*), NEWRANK, IERROR
LOGICAL PERIODS(*)
USE mpi_f08
MPI_Cart_map(comm, ndims, dims, periods, newrank, ierror)
TYPE(MPI_Comm), INTENT(IN) :: comm
INTEGER, INTENT(IN) :: ndims, dims(ndims)
LOGICAL, INTENT(IN) :: periods(ndims)
INTEGER, INTENT(OUT) :: newrank
INTEGER, OPTIONAL, INTENT(OUT) :: ierror
comm
: Input communicator (handle).ndims
: Number of dimensions of Cartesian structure (integer).dims
: Integer array of size ndims specifying the number of processes- in each coordinate direction.
periods
: Logical array of size ndims specifying the periodicity- specification in each coordinate direction.
newrank
: Reordered rank of the calling process; MPI_UNDEFINED if- calling process does not belong to grid (integer).
ierror
: Fortran only: Error status (integer).
:ref:`MPI_Cart_map` and :ref:`MPI_Graph_map` can be used to implement all other topology functions. In general they will not be called by the user directly, unless he or she is creating additional virtual topology capability other than that provided by MPI. :ref:`MPI_Cart_map` computes an "optimal" placement for the calling process on the physical machine. A possible implementation of this function is to always return the rank of the calling process, that is, not to perform any reordering.
.. seealso::
* :ref:`MPI_Graph_map`