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+++ b/scripts/general/isa.m
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+## Copyright (C) 2004 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, 59 Temple Place - Suite 330, Boston, MA
+## 02111-1307, USA.
+
+## -*- texinfo -*-
+## @deftypefn {Function File} {} isa (@var{x}, @var{class})
+## Return true if @var{x} is a value from the class @var{class}.
+## @end deftypefn
+
+## Author: Paul Kienzle <pkienzle@users.sf.net>
+## Adapted-by: jwe
+
+function retval = isa (x, cname)
+  retval = strcmp (class (f), cname);
+endfunction