anchor.diff:         atom2_tag = " "
          rmax = -1
          nb = -1
  +       osmooth = .false.
   c
   c      ------------------------
   c      allocate io file array
  
positive.code:        end do
  c       
  c      average RDF over the frames
         gr = gr/real(naver)
         if(overb) 
       +   write(*,*) "averaging over ",naver," smaples"
         dr = rmax/nb
         do k=1,nb
           write(fn_out,'(2F12.6)') 
  
negative.code:             atom2_tag = buffer
            end if
            go to 16
         else if(buffer.eq."-smooth") then
            osmooth = .true.
            goto 16
         else if(buffer.eq."-rmax") then
            i = i+1
            call my_get_command_argument(i,buffer,l,istatus)
  