anchor.diff:    character(len=1000) :: input_file, output_file
     integer(hid_t) :: handle_in, handle_out, g_peeled, g_binned
     real(dp) :: time1, time2, time
  -
  +  
     call hdf5_set_compression(.true.)
   
     ! Retrieve command-line arguments
  
positive.code:   if(trim(input_file)=="".or.trim(output_file)=="") then
       stop "Usage: bin/rt input_file output_file"
    end if
  
    ! Start up multi-processing if needed
    call mp_initialize()
  
    ! SETUP
  
    if(main_process()) call message_section('Initial setup')
  
    handle_in = hdf5_open_read(input_file)
  
  
negative.code:      call warn("main", "no dust present, so skipping temperature iterations")
       n_lucy_iter=0
    end if
    
    ! Loop over Lucy iterations
    do iter=1,n_lucy_iter
  
  