NAME

       MPI_Group_translate_ranks  -  Translates  the  ranks of processes in one group to those in
       another group.

SYNTAX

C Syntax

       #include <mpi.h>
       int MPI_Group_translate_ranks(MPI_Group group1, int n,
            int *ranks1, MPI_Group group2, int *ranks2)

Fortran Syntax

       INCLUDE 'mpif.h'
       MPI_GROUP_TRANSLATE_RANKS(GROUP1, N, RANKS1, GROUP2, RANKS2,
                 IERROR)
            INTEGER   GROUP1, N, RANKS1(*), GROUP2, RANKS2(*), IERROR

C++ Syntax

       #include <mpi.h>
       static void Group::Translate_ranks (const Group& group1, int n,
            const int ranks1[], const Group& group2, int ranks2[])

INPUT PARAMETERS

       group1    First group (handle).

       n         Number of ranks in ranks1 and ranks2 arrays (integer).

       ranks1    Array of zero or more valid ranks in group1.

       group2    Second group (handle).

OUTPUT PARAMETERS

       ranks2    Array of corresponding ranks in group2,  MPI_UNDEFINED  when  no  correspondence
                 exists.

       IERROR    Fortran only: Error status (integer).

DESCRIPTION

       This function is important for determining the relative numbering of the same processes in
       two different groups. For instance, if one knows the ranks of  certain  processes  in  the
       group of MPI_COMM_WORLD, one might want to know their ranks in a subset of that group.

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.