--- a/scripts/ChangeLog	Thu Dec 16 09:24:01 2010 -0800
+++ b/scripts/ChangeLog	Thu Dec 16 19:43:45 2010 -0500
@@ -1,3 +1,7 @@
+2010-12-16  Ben Abbott <bpabbott@mac.com>
+
+	* plot/isprop.m: New function.
+
 2010-12-16  Olaf Till <olaf.till@uni-jena.de>
 
 	* optimization/sqp.m: Fix indexing error in sqp bounds selection. 

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/scripts/plot/isprop.m	Thu Dec 16 19:43:45 2010 -0500
@@ -0,0 +1,50 @@
+## Copyright (C) 2010 Ben Abbott
+##
+## 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 3 of the License, 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, see
+## <http://www.gnu.org/licenses/>.
+
+## -*- texinfo -*-
+## @deftypefn  {Function File} {@var{res} =} isprop (@var{h}, @var{prop})
+## Determines if @var{prop} is a property of the object with handle, @var{h}.
+## @seealso{get, set}
+## @end deftypefn
+
+## Author: Ben Abbott  <bpabbott@mac.com>
+
+function res = isprop (h, prop)
+  ## Check input
+  if (nargin < 1 || nargin > 2)
+    print_usage ();
+  endif
+ 
+  if (! ishandle (h))
+    error ("isprop: first input argument must be a handle");
+  elseif (! ischar (prop))
+    error ("isprop: second input argument must be string");
+  endif
+
+  res = true;
+  try
+    v = get (h, prop);
+  catch
+    res = false;
+  end_try_catch
+endfunction
+
+%!assert (isprop (0, "foobar"), false)
+
+%!assert (isprop (0, "screenpixelsperinch"), true)
+