anchor.diff:  
   %% @private
   %% Write the average to files and return the name of the files.
  -write_to_files(TypeToTimeAndBytes, EvalId, EvalNumber) ->
  -    PlotDir = root_plot_dir() ++ "/"
  -           ++ EvalId ++ "/"
  -           ++ EvalNumber ++ "/",
  +write_to_files(TypeToTimeAndBytes, PlotDir) ->
       filelib:ensure_dir(PlotDir),
   
       lists:foldl(
           fun({Type, List}, InputFiles) ->
  -            %% truncate file
               InputFile = PlotDir ++ Type ++ ".csv",
  -            file:write_file(InputFile, "", [write]),
   
               lists:foreach(
                   fun({Time, Bytes}) ->
                       Line = io_lib:format("~w,~w\n", [Time, Bytes]),
  +                    lager:info("LINE : ~p", [Line]),
                       file:write_file(InputFile, Line, [append])
                   end,
                   List
  
positive.code: 
  %% @private
  output_file(PlotDir) ->
      PlotDir ++ "/plot.pdf".
  
  %% @private
  only_dirs(Dir) ->
      lager:info("ONLY DIRS"),
      {ok, DirFiles} = file:list_dir(Dir),
  
      lager:info("FILES ~p", [DirFiles]),
  
      %% Ignore files
      Dirs = lists:filter(
          fun(Elem) ->
              filelib:is_dir(Dir ++ "/" ++ Elem)
          end,
          DirFiles
      ),
  
      lager:info("DIRS ~p", [Dirs]),
  
      Dirs.
  
  %% @private
  only_csv_files(LogDir) ->
  
negative.code:             "/usr/bin/gnuplot"
      end,
      Command = Bin ++ " -e \""
                    ++ "outputname='" ++ OutputFile ++ "'; "
                    ++ "inputnames='" ++ join_filenames(InputFiles) ++ "'; "
                    ++ "titles='" ++  join_titles(Titles) ++ "'\" " ++ plot_file(),
      os:cmd(Command).
  