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+// Template array classes                              -*- 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 (octave_Array3_h)
+#define octave_Array3_h 1
+
+#if defined (__GNUG__)
+#pragma interface
+#endif
+
+#define HEAVYWEIGHT_INDEXING 1
+
+#include <cassert>
+#include <cstdlib>
+
+#include "Array2.h"
+#include "lo-error.h"
+
+class idx_vector;
+
+// Three dimensional array class.
+
+template <class T>
+class Array3 : public Array2<T>
+{
+protected:
+
+  int d3;
+
+  Array3 (T *d, int n, int m, int k) : Array2<T> (d, n, m*k)
+    {
+      d2 = m;
+      d3 = k;
+      set_max_indices (3);
+    }
+
+public:
+
+  Array3 (void) : Array2<T> ()
+    {
+      d2 = 0;
+      d3 = 0;
+      set_max_indices (3);
+    }
+
+  Array3 (int n, int m, int k) : Array2<T> (n, m*k)
+    {
+      d2 = m;
+      d3 = k;
+      set_max_indices (3);
+    }
+
+  Array3 (int n, int m, int k, const T& val) : Array2<T> (n, m*k, val)
+    {
+      d2 = m;
+      d3 = k;
+      set_max_indices (3);
+    }
+
+  Array3 (const Array3<T>& a) : Array2<T> (a)
+    {
+      d2 = a.d2;
+      d3 = a.d3;
+      set_max_indices (3);
+    }
+
+  ~Array3 (void) { }
+
+  Array3<T>& operator = (const Array3<T>& a)
+    {
+      if (this != &a && rep != a.rep)
+	{
+	  Array<T>::operator = (a);
+	  d1 = a.d1;
+	  d2 = a.d2;
+	  d3 = a.d3;
+	}
+
+      return *this;
+    }
+
+  int dim3 (void) const { return d3; }
+
+  T& elem (int i, int j, int k) { return Array2<T>::elem (i, d2*k+j); }
+  T& checkelem (int i, int j, int k);
+  T& operator () (int i, int j, int k) { return checkelem (i, j, k); }
+
+  // No checking.
+
+  T& xelem (int i, int j, int k) { return Array2<T>::xelem (i, d2*k+j); }
+
+  T elem (int i, int j, int k) const;
+  T checkelem (int i, int j, int k) const;
+  T operator () (int i, int j, int k) const;
+
+  void resize (int n, int m, int k);
+  void resize (int n, int m, int k, const T& val);
+
+#ifdef HEAVYWEIGHT_INDEXING
+  void maybe_delete_elements (idx_vector& i, idx_vector& j, idx_vector& k);
+
+  Array3<T> value (void);
+#endif
+};
+
+template <class LT, class RT>
+int assign (Array3<LT>& lhs, const Array3<RT>& rhs);
+
+#endif
+
+/*
+;;; Local Variables: ***
+;;; mode: C++ ***
+;;; page-delimiter: "^/\\*" ***
+;;; End: ***
+*/