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,
            const int ranks1[], MPI_Group group2, int ranks2[])

Fortran Syntax

       USE MPI
       ! or the older form: INCLUDE 'mpif.h'
       MPI_GROUP_TRANSLATE_RANKS(GROUP1, N, RANKS1, GROUP2, RANKS2,
                 IERROR)
            INTEGER   GROUP1, N, RANKS1(*), GROUP2, RANKS2(*), IERROR

Fortran 2008 Syntax

       USE mpi_f08
       MPI_Group_translate_ranks(group1, n, ranks1, group2, ranks2, ierror)
            TYPE(MPI_Group), INTENT(IN) :: group1, group2
            INTEGER, INTENT(IN) :: n, ranks1(n)
            INTEGER, INTENT(OUT) :: ranks2(n)
            INTEGER, OPTIONAL, INTENT(OUT) :: 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.

4.1.6                                             Sep 30, 2023                      MPI_Group_translate_ranks(3)