NAME

       MPI_Group_range_incl - Creates a new group from ranges of ranks in an existing group.

SYNTAX

C Syntax

       #include <mpi.h>
       int MPI_Group_range_incl(MPI_Group group, int n, int ranges[][3],
            MPI_Group *newgroup)

Fortran Syntax

       INCLUDE 'mpif.h'
       MPI_GROUP_RANGE_INCL(GROUP, N, RANGES, NEWGROUP, IERROR)
            INTEGER   GROUP, N, RANGES(3,*), NEWGROUP, IERROR

C++ Syntax

       #include <mpi.h>
       Group Group::Range_incl(int n, const int ranges[][3]) const

INPUT PARAMETERS

       group     Group (handle).

       n         Number of triplets in array ranges (integer).

       ranges    A one-dimensional array of integer triplets, of the form (first rank, last rank,
                 stride) indicating ranks in group or processes to be included in newgroup.

OUTPUT PARAMETERS

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

       IERROR    Fortran only: Error status (integer).

DESCRIPTION

       If ranges consist of the triplets

           (first1, last1, stride1), ..., (firstn, lastn, striden)

       then newgroup consists of the sequence of processes in group with ranks

                                                        last(1)-first(1)
         first(1), first(1) + stride(1),..., first(1) + ---------------- stride(1),...
                                                            stride(1)

                                                        last(n)-first(n)
         first(n), first(n) + stride(n),..., first(n) + ---------------- stride(n).
                                                            stride(n)

       Each computed rank must be a valid rank in group and all computed ranks must be  distinct,
       or  else the program is erroneous. Note that we may have first(i) > last(i), and stride(i)
       may be negative, but cannot be zero.

       The functionality of this routine is specified to be equivalent to expanding the array  of
       ranges  to  an  array  of  the included ranks and passing the resulting array of ranks and
       other arguments to MPI_Group_incl. A call to MPI_Group_incl is equivalent  to  a  call  to
       MPI_Group_range_incl  with  each  rank  i  in ranks replaced by the triplet (i,i,1) in the
       argument ranges.

NOTE

       This implementation does not currently check to see that the list of ranges to include are
       valid ranks in the 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.

SEE ALSO

       MPI_Group_incl
       MPI_Group_free