--- a/scripts/testfun/private/compare_plot_demos.m
+++ b/scripts/testfun/private/compare_plot_demos.m
@@ -18,25 +18,26 @@
 
 ## -*- texinfo -*-
 ## @deftypefn  {Function File} {} compare_plot_demos ()
+## @deftypefnx {Function File} {} compare_plot_demos ("toolkits", @{@var{toolkit1}, @var{toolkit2}, @dots{}@})
 ##
-## Uses @code{dump_demos} and @code{html_compare} to produce an html
-## comparison of the plot demos for each of Octave's graphics
-## toolkits. 
+## Uses @code{dump_demos} and @code{html_compare_plot_demos} to produce an
+## html comparison of the plot demos for each of Octave's graphics toolkits. 
 ##
-## A m-file names `dump_plots.m' will be created in the pwd. This function
-## will be used to render and save the plot demo images.
+## An m-file named @file{dump_plots.m} will be created in the current working
+## directory. This function will be used to render and save the plot demo
+## images.
 ##
-## If they do not already exist, directories for each graphics toolkit
-## are created. Each toolkit's directory will be populated with images
+## If they do not already exist, directories for each available graphics
+## toolkit are created.  Each toolkit's directory will be populated with images
 ## of each plot demo in the png format.
 ##
-## Finally, an htlm document named `compare_plot_demos.html' is produced.
-## This page places each toolkits images side by side for a conventient
+## Finally, an html document named @file{compare_plot_demos.html} is produced.
+## This page places each toolkit's images side by side for a convenient
 ## comparison of the results.
 ##
-## @deftypefnx  {Function File} {} compare_plot_demos (@var{toolkits})
-## @var{toolkits} is used to specify a subset of the available graphics
-## toolkits. This list may also include `matlab'.
+## If the property @qcode{"toolkits"} is given then compare only the listed
+## toolkits in the cell string.  The list may also include the toolkit
+## @qcode{"matlab"}.
 ##
 ## @end deftypefn
 
@@ -44,75 +45,75 @@
 
 function compare_plot_demos (varargin)
 
-  in.toolkits = available_graphics_toolkits ();
-  in.directory = "plot";
-  in.fmt = "png";
-  in.fcn_file = "";
-  in.replace_images = false;
+  arg.toolkits = available_graphics_toolkits ();
+  arg.directories = {"plot/appearance", "plot/draw", "plot/util"};
+  arg.fmt = "png";
+  arg.fcn_file = "";
+  arg.replace_images = false;
 
   for n = 1:2:numel(varargin)
     if (! ischar (varargin{n}))
       print_usage ();
     else
-      in.(varargin{n}) = varargin{n+1};
+      arg.(varargin{n}) = varargin{n+1};
     endif
   endfor
 
-  if (ischar (in.toolkits))
-    in.toolkits = {in.toolkits};
-  elseif (! iscellstr (in.toolkits))
-    error ("compare_plot_demos: Invalid value for ""toolkits""")
+  if (ischar (arg.toolkits))
+    arg.toolkits = {arg.toolkits};
+  elseif (! iscellstr (arg.toolkits))
+    error ('compare_plot_demos: Invalid value for "toolkits"')
   endif
 
-  if (! ischar (in.directory))
-    error ("compare_plot_demos: Invalid value for ""directory""")
+  if (ischar (arg.directories))
+    arg.directories = {arg.directories};
+  elseif (! iscellstr (arg.directories))
+    error ('compare_plot_demos: Invalid value for "directory"')
   endif
 
-  if (! ischar (in.fmt))
-    error ("compare_plot_demos: Invalid value for ""fmt""")
+  if (! ischar (arg.fmt))
+    error ('compare_plot_demos: Invalid value for "fmt"')
   endif
 
-  if (isempty (in.fcn_file))
-    in.fcn_file = sprintf ("dump_%s_demos.m", in.directory);
+  if (isempty (arg.fcn_file))
+    arg.fcn_file = "dump_plot_demos.m";
   endif
 
-  ## Generate "dump_plots.m" for rendering/saving the plot demo images
-  dump_demos ("plot", in.fcn_file, in.fmt)
+  ## Generate "dump_plot_demos.m" for rendering/saving the plot demo images
+  dump_demos (arg.directories, arg.fcn_file, arg.fmt);
 
-  [~, fcn_name] = fileparts (in.fcn_file);
+  [~, fcn_name] = fileparts (arg.fcn_file);
 
   ## Generate the plot demo images for each toolkit
   cwd = pwd ();
   unwind_protect
     addpath (pwd);
-    for n = 1:numel(in.toolkits)
-      dirs = dir ();
-      dirs = dirs([dirs.isdir]);
-      if (! any (strcmp ({dirs.name}, in.toolkits{n})))
-        mkdir (in.toolkits{n})
+    for n = 1:numel (arg.toolkits)
+      if (! isdir (fullfile (cwd, arg.toolkits{n})))
+        mkdir (arg.toolkits{n});
       endif
-      cd (in.toolkits{n})
-      if (! isempty (dir (strcat ("*.", in.fmt))) && in.replace_images)
-        delete (strcat ("*.", in.fmt))
+      cd (arg.toolkits{n});
+      if (arg.replace_images && ! isempty (dir (["*." arg.fmt])))
+        delete (["*." arg.fmt]);
       endif
-      if (! strcmp (in.toolkits{n}, "matlab"))
-        close all
-        graphics_toolkit (in.toolkits{n});
+      if (! strcmp (arg.toolkits{n}, "matlab"))
+        close all;
+        graphics_toolkit (arg.toolkits{n});
         try
           eval (fcn_name);
         catch
-          fprintf ("Error running plot demos for ""%s"" toolkit\n", in.toolkits{n})
-          disp (lasterror)
+          printf ("Error running plot demos for ""%s"" toolkit\n", arg.toolkits{n});
+          disp (lasterror);
         end_try_catch
       endif
-      cd (cwd)
+      cd (cwd);
     endfor
   unwind_protect_cleanup
     rmpath (cwd);
   end_unwind_protect
 
   ## Generate the html comparison of the images
-  ## TODO - pass the toolkits{} to allow num of columns to be formated
+  ## TODO: pass the toolkits{} to allow number of columns to be formatted
   html_compare_plot_demos ("output", "compare_plot_demos.html")
 
 endfunction