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+/* ****************************************************************************
+ Copyright (C) 2003-2004 Eva Brucherseifer <eva.brucherseifer@basyskom.com>
+ 2005 Stanislav Visnovsky <visnovsky@kde.org>
+
+ This file is part of the KDE project
+
+ This program 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 of the License, or
+ (at your option) any later version.
+
+ This program 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 this program; if not, write to the Free Software
+ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+
+ In addition, as a special exception, the copyright holders give
+ permission to link the code of this program with any edition of
+ the Qt library by Trolltech AS, Norway (or with modified versions
+ of Qt that use the same license as Qt), and distribute linked
+ combinations including the two. You must obey the GNU General
+ Public License in all respects for all of the code used other than
+ Qt. If you modify this file, you may extend this exception to
+ your version of the file, but you are not obligated to do so. If
+ you do not wish to do so, delete this exception statement from
+ your version.
+
+**************************************************************************** */
+
+#ifndef STRINGDISTANCE_H
+#define STRINGDISTANCE_H
+
+#include <qstring.h>
+
+//#include <boost/numeric/ublas/matrix.hpp>
+
+
+/** Private copy constructor and copy assignment ensure classes derived from
+ * class noncopyable cannot be copied.
+ * Taken from Boost library
+ * Contributed by Dave Abrahams
+ *
+ * If anyone needs a namespace here, please tell me at eva@rt.e-technik.tu-darmstadt.de
+ */
+class NonCopyable
+{
+protected:
+ NonCopyable(){}
+ virtual ~NonCopyable(){}
+private: // emphasize the following members are private
+ NonCopyable( const NonCopyable& );
+ const NonCopyable& operator=( const NonCopyable& );
+};
+
+
+/**
+ * @class Distance
+ * @author Eva Brucherseifer
+ *
+ * The class Distance calculates the distance
+ * between two Entities (left & right).
+ * It is the parent for other distance-classes.
+ */
+class Distance : public NonCopyable
+{
+public:
+ virtual ~Distance(){}
+ double operator()(const QString& left, const QString& right);
+
+ int editCostReplace() { return editCost_replace_base; }
+ static int debug;
+
+protected:
+ virtual double calculate(const QString& left_string, const QString& right_string) = 0;
+ int nodeDistance(const QString& left_letter, const QString& right_letter);
+ static const int editCost_replace_base;
+ double m_distance;
+};
+
+
+double relativeDistance(double distance, const QString& left_string, const QString right_string);
+
+
+/**
+ * @class HammingDistance
+ * @author Eva Brucherseifer
+ *
+ * The class HammingDistance is based on an algorithm
+ * of Hamming. It increase the distance if the nodes from
+ * the tree are not the same. Also called edit-distance.
+ */
+class HammingDistance : public Distance
+{
+protected:
+ virtual double calculate(const QString& left_string, const QString& right_string);
+ int editCostReplace() { return editCost; }
+ static const int editCost;
+};
+
+/**
+ * @class LevenshteinDistance
+ * @author Eva Brucherseifer
+ *
+ * The class LevenshteinDistance is based on an algorithm
+ * of Levenshtein. It search for the minimum distance of
+ * two trees. You can specify the distance between
+ * a gap & a node and between two different nodes.
+ */
+class LevenshteinDistance : public Distance
+{
+protected:
+ virtual double calculate(const QString& left_string, const QString& right_string);
+ int editCostReplace() { return editCost_replace; }
+ static const int editCost_replace;
+ static const int editCost_insert;
+ static const int editCost_delete;
+};
+
+
+/** wrapper function for replacement of fstrcmp from gettext */
+inline double fstrcmp(const QString& left, const QString& right)
+{
+ return LevenshteinDistance()(left,right);
+}
+
+
+#endif