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MPI_Group_range_incl(3) man page (version 1.3.4)

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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

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++  func-
       tions  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

1.3.4                            Nov 11, 2009          MPI_Group_range_incl(3)

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