MPI_Group_incl(3)                  Open MPI                  MPI_Group_incl(3)



NAME
       MPI_Group_incl  - Produces a group by reordering an existing group and
       taking only listed members.


SYNTAX
C Syntax
       #include <mpi.h>
       int MPI_Group_incl(MPI_Group group, int n, int *ranks,
            MPI_Group *newgroup)


Fortran Syntax
       INCLUDE 'mpif.h'
       MPI_GROUP_INCL(GROUP, N, RANKS, NEWGROUP, IERROR)
            INTEGER   GROUP, N, RANKS(*), NEWGROUP, IERROR


C++ Syntax
       #include <mpi.h>
       Group Group::Incl(int n, const int ranks[]) const


INPUT PARAMETERS
       group     Group (handle).

       n         Number of elements in array ranks (and size of
                 newgroup)(integer).

       ranks     Ranks of processes in group to appear in newgroup (array of
                 integers).


OUTPUT PARAMETERS
       newgroup  New group derived from above, in the order defined by ranks
                 (handle).

       IERROR    Fortran only: Error status (integer).


DESCRIPTION
       The function MPI_Group_incl creates a group group_out that consists of
       the n processes in group with ranks rank[0], ..., rank[n-1]; the
       process with rank i in group_out is the process with rank ranks[i] in
       group. Each of the n elements of ranks must be a valid rank in group
       and all elements must be distinct, or else the program is erroneous. If
       n = 0, then group_out is MPI_GROUP_EMPTY. This function can, for
       instance, be used to reorder the elements of a group.


NOTE
       This implementation does not currently check to ensure that there are
       no duplicates in the list of ranks.


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.


SEE ALSO
       MPI_Group_compare
       MPI_Group_range_incl
       MPI_Group_free




1.4.1                            Jan 14, 2010                MPI_Group_incl(3)
