run_number Subroutine

  subroutine run_number (sel, nbeta)
    implicit none
    integer, intent (out) :: sel
    integer, intent (in) :: nbeta

100 continue
    do 
       call text
       call text ('Lowest run number for this scan (0-999):')
       read (interactive_input, *, err = 100) sel
       if (sel + nbeta - 1 > 999) then
          write (6,*) 'The lowest run number for this scan must be less than ',1000-nbeta
          call try_again
       else if (sel < 0) then
          write (6,*) 'The lowest run number for this scan must be greater than zero.'
          call try_again
       else
          return
       end if
    end do

  end subroutine run_number