program rounding
implicit none
  integer                     :: j, k, err, ieee_flags, rounding_type
  real                        :: s1, s2   ! enkel precision
  double precision, parameter :: facit = 14.39272672286577d0
  character (len = 9) :: out
!
! round är en strängvektor
!
  character (len = *), dimension(4), parameter :: &
    round = (/ 'nearest ', 'tozero  ', 'positive', 'negative' /)

  print'(a)',   'type            s1        error      s2        error'

  do rounding_type = 1, 4  ! testa de fyra avrundningsriktningarna
!
!   Sätt "rounding direction" med en speciell Sun-rutin
!   (ej standard).
!
    err = ieee_flags('set', 'direction', round(rounding_type), out)
!
!   Beräkna summorna
!
    s1 = 0.0
    s2 = 0.0
    do k = 1, 1000000
      s1 = s1 + 1.0 / k
      s2 = s2 + 1.0 / (1000001 - k)
    end do

    print '(a, 2(f12.7, f9.4))', round(rounding_type) // ' :', &
                                 s1, s1 - facit, s2, s2 - facit
  end do

end program rounding