--- a/scripts/image/colormap.m
+++ b/scripts/image/colormap.m
@@ -1,42 +1,61 @@
-function cmap = colormap(map)
+# Copyright (C) 1995 John W. Eaton
+# 
+# This file is part of Octave.
+# 
+# Octave is free software; you can redistribute it and/or modify it
+# under the terms of the GNU General Public License as published by the
+# Free Software Foundation; either version 2, or (at your option) any
+# later version.
+# 
+# Octave is distributed in the hope that it will be useful, but WITHOUT
+# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+# FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+# for more details.
+# 
+# You should have received a copy of the GNU General Public License
+# along with Octave; see the file COPYING.  If not, write to the Free
+# Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+function cmap = colormap (map)
 
 # Set the current colormap.
 # 
-# colormap(map) sets the current colormap to map.  map should be an n row
-# by 3 column matrix. The columns contain red, green, and blue intensities
-# respectively.  All entries should be between 0 and 1 inclusive. The new
-# colormap is returned.
+# colormap (map) sets the current colormap to map.  map should be an n
+# row by 3 column matrix. The columns contain red, green, and blue
+# intensities respectively.  All entries should be between 0 and 1
+# inclusive. The new colormap is returned.
 # 
-# colormap("default") restores the default colormap (a gray scale colormap
-# with 64 entries). The default colormap is returned.
+# colormap ("default") restores the default colormap (a gray scale
+# colormap with 64 entries). The default colormap is returned.
 # 
 # colormap with no arguments returns the current colormap.
 
-# Author:
-#  Tony Richardson
-#  amr@mpl.ucsd.edu
-#  July 1994
+# Written by Tony Richardson (amr@mpl.ucsd.edu) July 1994.
 
   global CURRENT_COLOR_MAP
 
   cmap_name = "CURRENT_COLOR_MAP";
 
-  if(nargin == 1)
-    if(isstr(map))
-      if(strcmp(map,"default"))
+  if (nargin == 1)
+    if (isstr (map))
+      if (strcmp (map, "default"))
         CURRENT_COLOR_MAP = gray;
       else
-        error("invalid argument");
+        error ("invalid argument");
       endif
     else
-      # Set the new color map
+# Set the new color map
       CURRENT_COLOR_MAP = map;
     endif
-  elseif(exist(cmap_name) == 0)
-    # If global color map doesn't exist, create the default map.
+  elseif (nargin == 0 && exist (cmap_name) == 0)
+# If global color map doesn't exist, create the default map.
     CURRENT_COLOR_MAP = gray;
+  else
+    usage ("colormap (map)");
   endif
 
-  # Return current color map.
+# Return current color map.
+
   cmap = CURRENT_COLOR_MAP;
+
 endfunction