--- a/scripts/image/summer.m
+++ b/scripts/image/summer.m
@@ -17,33 +17,34 @@
 ## <http://www.gnu.org/licenses/>.
 
 ## -*- texinfo -*-
-## @deftypefn {Function File} {} summer (@var{n})
-## Create color colormap.  This colormap is green to yellow.
-## The argument @var{n} should be a scalar.  If it
-## is omitted, the length of the current colormap or 64 is assumed.
+## @deftypefn  {Function File} {@var{map} =} summer ()
+## @deftypefnx {Function File} {@var{map} =} summer (@var{n})
+## Create color colormap.  This colormap varies from green to yellow.
+## The argument @var{n} must be a scalar.  
+## If unspecified, the length of the current colormap, or 64, is used.
 ## @seealso{colormap}
 ## @end deftypefn
 
 ## Author:  Kai Habel <kai.habel@gmx.de>
 ## Date:  06/03/2000
-function map = summer (number)
+function map = summer (n)
 
   if (nargin == 0)
-    number = rows (colormap);
+    n = rows (colormap);
   elseif (nargin == 1)
-    if (! isscalar (number))
+    if (! isscalar (n))
       error ("summer: argument must be a scalar");
     endif
   else
     print_usage ();
   endif
 
-  if (number == 1)
+  if (n == 1)
     map = [0, 0.5, 0.4];  
-  elseif (number > 1)
-    r = (0:number - 1)' ./ (number - 1);
+  elseif (n > 1)
+    r = (0:n - 1)' ./ (n - 1);
     g = 0.5 + r ./ 2;
-    b = 0.4 * ones (number, 1);
+    b = 0.4 * ones (n, 1);
 
     map = [r, g, b];
   else
@@ -56,5 +57,5 @@
 %! ## Show the 'summer' colormap as an image
 %! image (1:64, linspace (0, 1, 64), repmat (1:64, 64, 1)')
 %! axis ([1, 64, 0, 1], "ticy", "xy")
-%! colormap summer
+%! colormap (summer (64))