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--- /dev/null
+++ b/liboctave/DAE.cc
@@ -0,0 +1,70 @@
+// DAE.cc                                               -*- C++ -*-
+/*
+
+Copyright (C) 1996 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.
+
+*/
+
+#if defined (__GNUG__)
+#pragma implementation
+#endif
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include "DAE.h"
+#include "lo-error.h"
+
+DAE::DAE (const ColumnVector& x, const ColumnVector& xxdot,
+	  double t, DAEFunc& f)
+  : base_diff_eqn (x, t), DAEFunc (f), xdot (xxdot)
+{
+  if (x.length () != xdot.length ())
+    ; // XXX FIXME XXX -- exception!
+}
+
+void
+DAE::initialize (const ColumnVector& xx, double t)
+{
+  if (xx.length () != xdot.length ())
+    ; // XXX FIXME XXX -- exception!
+  else
+    base_diff_eqn::initialize (xx, t);
+}
+
+void
+DAE::initialize (const ColumnVector& xx, const ColumnVector& xxdot,
+		 double t)
+{
+  if (xx.length () != xxdot.length ())
+    ; // XXX FIXME XXX -- exception!
+  else
+    {
+      base_diff_eqn::initialize (xx, t);
+      xdot = xxdot;
+    }
+}
+
+/*
+;;; Local Variables: ***
+;;; mode: C++ ***
+;;; page-delimiter: "^/\\*" ***
+;;; End: ***
+*/