/*D
   MPI_Cart_rank - Determines process rank in communicator given Cartesian location

Synopsis:
.vb
int MPI_Cart_rank(MPI_Comm comm, const int coords[], int *rank)
.ve

Input Parameters:
+ comm - communicator with Cartesian structure (handle)
- coords - integer array (of size ndims) specifying the Cartesian coordinates of a process (integer)

Output Parameters:
. rank - rank of specified process (integer)

Notes:
 Out-of-range coordinates are erroneous for non-periodic dimensions.
 Versions of MPICH before 1.2.2 returned 'MPI_PROC_NULL' for the rank in this
 case.

.N ThreadSafe

.N Fortran

.N Errors
.N MPI_SUCCESS
.N MPI_ERR_ARG
.N MPI_ERR_COMM
.N MPI_ERR_OTHER

D*/

