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+// pt-mat.h                                      -*- C++ -*-
+/*
+
+Copyright (C) 1992, 1993, 1994, 1995 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 (octave_tree_mat_h)
+#define octave_tree_mat_h 1
+
+#if defined (__GNUG__)
+#pragma interface
+#endif
+
+class ostream;
+
+class tree_constant;
+class tree_return_list;
+
+#include "pt-exp.h"
+
+// General matrices.  This allows us to construct matrices from
+// other matrices, variables, and functions.
+
+class
+tree_matrix : public tree_expression
+{
+public:
+  enum dir
+    {
+      md_none,
+      md_right,
+      md_down,
+    };
+
+  tree_matrix (void)
+    : tree_expression (), direction (tree_matrix::md_none),
+      element (0), next (0) { }
+
+  tree_matrix (tree_expression *e, tree_matrix::dir d)
+    : tree_expression (), direction (d), element (e), next (0) { }
+
+  ~tree_matrix (void);
+
+  int is_matrix_constant (void) const;
+
+  tree_matrix *chain (tree_expression *e, tree_matrix::dir d);
+  tree_matrix *reverse (void);
+  int length (void);
+
+  tree_return_list *to_return_list (void);
+
+  tree_constant eval (int print);
+
+  void print_code (ostream& os);
+
+private:
+  tree_matrix::dir direction; // Direction from the previous element.
+  tree_expression *element;
+  tree_matrix *next;
+};
+
+#endif
+
+/*
+;;; Local Variables: ***
+;;; mode: C++ ***
+;;; page-delimiter: "^/\\*" ***
+;;; End: ***
+*/