+## Copyright (C) 2004-2012 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 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} {} isa (@var{obj}, @var{class})
+## Return true if @var{obj} is an object from the class @var{class}.
+## @seealso{class, typeinfo}
+## @end deftypefn
+
+## Author: Paul Kienzle <pkienzle@users.sf.net>
+## Adapted-by: jwe
+
+function retval = isa (obj, cname)
+
+ if (nargin != 2)
+ print_usage ();
+ endif
+
+ persistent float_classes = {"double", "single"};
+
+ persistent fnum_classes = {"double", "single", ...
+ "uint8", "uint16", "uint32", "uint64", ...
+ "int8", "int16", "int32", "int64"};
+
+ if (strcmp (cname, "float"))
+ retval = any (strcmp (class (obj), float_classes));
+ elseif (strcmp (cname, "numeric"))
+ retval = any (strcmp (class (obj), fnum_classes));
+ else
+ class_of_x = class (obj);
+ retval = strcmp (class_of_x, cname);
+ if (! retval && isobject (obj))
+ retval = __isa_parent__ (obj, cname);
+ endif
+ endif
+
+endfunction
+
+%!assert (isa ("char", "float"), false)
+%!assert (isa (logical (1), "float"), false)
+%!assert (isa (double (13), "float"), true)
+%!assert (isa (single (13), "float"), true)
+%!assert (isa (int8 (13), "float"), false)
+%!assert (isa (int16 (13), "float"), false)
+%!assert (isa (int32 (13), "float"), false)
+%!assert (isa (int64 (13), "float"), false)
+%!assert (isa (uint8 (13), "float"), false)
+%!assert (isa (uint16 (13), "float"), false)
+%!assert (isa (uint32 (13), "float"), false)
+%!assert (isa (uint64 (13), "float"), false)
+%!assert (isa ("char", "numeric"), false)
+%!assert (isa (logical (1), "numeric"), false)
+%!assert (isa (double (13), "numeric"), true)
+%!assert (isa (single (13), "numeric"), true)
+%!assert (isa (int8 (13), "numeric"), true)
+%!assert (isa (int16 (13), "numeric"), true)
+%!assert (isa (int32 (13), "numeric"), true)
+%!assert (isa (int64 (13), "numeric"), true)
+%!assert (isa (uint8 (13), "numeric"), true)
+%!assert (isa (uint16 (13), "numeric"), true)
+%!assert (isa (uint32 (13), "numeric"), true)
+%!assert (isa (uint64 (13), "numeric"), true)
+
+%!assert (isa (double (13), "double"));
+%!assert (isa (single (13), "single"));
+%!assert (isa (int8 (13), "int8"));
+%!assert (isa (int16 (13), "int16"));
+%!assert (isa (int32 (13), "int32"));
+%!assert (isa (int64 (13), "int64"));
+%!assert (isa (uint8 (13), "uint8"));
+%!assert (isa (uint16 (13), "uint16"));
+%!assert (isa (uint32 (13), "uint32"));
+%!assert (isa (uint64 (13), "uint64"));
+%!assert (isa ("string", "char"));
+%!assert (isa (true, "logical"));
+%!assert (isa (false, "logical"));
+%!assert (isa ({1, 2}, "cell"));
+%!test
+%! a.b = 1;
+%! assert (isa (a, "struct"));
+