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@@ -0,0 +1,93 @@
+// DAE.h                                                -*- C++ -*-
+/*
+
+Copyright (C) 1992, 1993 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, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+*/
+
+#if !defined (_DAE_h)
+#define _DAE_h 1
+
+#ifdef __GNUG__
+#pragma interface
+#endif
+
+#include <iostream.h>
+#include "ODE.h"
+#include "DAEFunc.h"
+#include "Matrix.h"
+#include "f77-uscore.h"
+
+#ifndef Vector
+#define Vector ColumnVector
+#endif
+
+class DAE : public ODE, public DAEFunc
+{
+public:
+
+  DAE (void);
+
+  DAE (int);
+
+  DAE (Vector& x, double time, DAEFunc& f);
+
+  DAE (Vector& x, Vector& xdot, double time, DAEFunc& f);
+
+ ~DAE (void);
+
+  Vector deriv (void);
+
+  virtual void initialize (Vector& x, double t);
+  virtual void initialize (Vector& x, Vector& xdot, double t);
+
+  Vector integrate (double t);
+
+  Matrix integrate (const Vector& tout, Matrix& xdot_out);
+  Matrix integrate (const Vector& tout, Matrix& xdot_out,
+		    const Vector& tcrit); 
+
+protected:
+
+/*
+ * Some of this is probably too closely related to DASSL, but hey,
+ * this is just a first attempt...
+ */
+
+  Vector xdot;
+
+private:
+
+  int restart;
+  int liw;  
+  int lrw;
+  int idid;
+  int *info;
+  int *iwork;
+  double *rwork;
+
+  friend int ddassl_j (double *time, double *state, double *deriv,
+		       double *pd, double *cj, double *rpar, int *ipar);
+
+  friend int ddassl_f (double *time, double *state, double *deriv,
+		       double *delta, int *ires, double *rpar, int *ipar);
+
+};
+
+#endif