MPI_Group_translate_ranks(3)       Open MPI       MPI_Group_translate_ranks(3)



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.




1.4.1                            Jan 14, 2010     MPI_Group_translate_ranks(3)
