eoGpMutate.h added containing 4 new mutation operators for eoParseTree class

eo/src/gp/eoGpMutate.h

@@ -0,0 +1,290 @@
+// -*- mode: c++; c-indent-level: 4; c++-member-init-indent: 8; comment-column: 35; -*-
+ 
+//-----------------------------------------------------------------------------
+// eoGpMutate.h : GP mutation
+// (c) Jeroen Eggermont 2001 for mutation operators
+
+/*
+    This library is free software; you can redistribute it and/or
+    modify it under the terms of the GNU Lesser General Public
+    License as published by the Free Software Foundation; either
+    version 2 of the License, or (at your option) any later version.
+ 
+    This library 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
+    Lesser General Public License for more details.
+ 
+    You should have received a copy of the GNU Lesser General Public
+    License along with this library; if not, write to the Free Software
+    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ 
+    Contact: todos@geneura.ugr.es, http://geneura.ugr.es
+             jeggermo@liacs.nl
+ */
+//-----------------------------------------------------------------------------
+
+#ifndef eoGpMutate_h
+#define eoGpMutate_h
+
+//-----------------------------------------------------------------------------
+
+#include <gp/eoParseTree.h>
+#include <list>
+#include <string>
+
+
+#include <EO.h>
+#include <eoOp.h>
+#include <gp/eoParseTree.h>
+#include <eoInit.h>
+
+using namespace gp_parse_tree;
+using namespace std;
+
+// Additional Mutation operators from 
+// TITLE:"Genetic Programming~An Introduction"
+// AUTHORS: Banzhaf, Nordin, Keller, Francone
+// ISBN: 3-920993-58-6
+// ISBN: 1-55860-510-X
+//
+// For the eoParseTree class
+
+/** eoPointMutation --> replace a Node with a Node of the same arity 
+\class eoPointMutation eoGpMutate.h gp/eoGpMutate.h	
+*/
+
+template<class FType, class Node>
+class eoPointMutation: public eoMonOp< eoParseTree<FType, Node> >
+{
+public:
+
+  typedef eoParseTree<FType, Node> EoType;
+
+  /**
+   * Constructor
+   * @param _initializor The vector of Nodes given to the eoGpDepthInitializer
+   */
+  eoPointMutation( vector<Node>& _initializor)
+    : eoMonOp<EoType>(), initializor(_initializor)
+  {};
+  
+  /// the class name
+  virtual string className() const { return "eoPointMutation"; };
+
+  /// Dtor
+  virtual ~eoPointMutation() {};
+
+  /**
+   * Mutate an individual
+   * @param _eo1 The individual that is to be changed
+   */
+  bool operator()(EoType& _eo1 )
+  {
+  	// select a random node i that is to be mutated
+	int i = rng.random(_eo1.size());
+	// request the arity of the node that is to be replaced
+	int arity = _eo1[i].arity();
+	
+	int j=0;
+	
+	do
+	{
+		j = rng.random(initializor.size());
+		
+	}while ((initializor[j].arity() != arity) && (_eo1[i] != initializor[j]));
+	
+	_eo1[i] = initializor[j];
+	
+      	
+	
+    	return true;
+  }
+
+private :
+	vector<Node>& initializor;
+
+};
+
+/** eoExpansionMutation --> replace a terminal with a randomly created subtree 
+\class eoExpansionMutation eoGpMutate.h gp/eoGpMutate.h
+ */
+
+template<class FType, class Node>
+class eoExpansionMutation: public eoMonOp< eoParseTree<FType, Node> >
+{
+public:
+
+  typedef eoParseTree<FType, Node> EoType;
+  
+  /**
+   * Constructor
+   * @param _init An instantiation of eoGpDepthInitializer
+   * @param _max_length the maximum size of an individual
+   */
+  eoExpansionMutation(eoInit<EoType>& _init, unsigned _max_length)
+    : eoMonOp<EoType>(), max_length(_max_length), initializer(_init)
+  {};
+  
+  /// The class name
+  virtual string className() const { return "eoExpansionMutation"; };
+
+  /// Dtor
+  virtual ~eoExpansionMutation() {};
+  /**
+   * Mutate an individual
+   * @param _eo1 The individual that is to be changed
+   */
+  bool operator()(EoType& _eo1 )
+  {
+	  int i = rng.random(_eo1.size());
+	  // look for a terminal
+          while (_eo1[i].arity() != 0)
+	  {
+	  	i= rng.random(_eo1.size());
+	  };
+	  
+	  // create a new tree to
+      	  EoType eo2;
+	  // make sure we get a tree with more than just a terminal
+	  do
+	  {
+      	  	initializer(eo2);
+	  }while(eo2.size() == 1);	
+	  
+	  int j = rng.random(eo2.size());
+	  // make sure we select a subtree (and not a terminal)
+	  while((eo2[j].arity() == 0))
+	  {
+	  	j = rng.random(eo2.size());
+	  };
+	  
+
+	  _eo1[i] = eo2[j]; // insert subtree
+
+	  _eo1.pruneTree(max_length);
+	  
+    return true;
+  }
+
+private :
+
+  unsigned max_length;
+  eoInit<EoType>& initializer;
+};
+
+/** eoCollapseSubtree -->  replace a subtree with a randomly chosen terminal
+\class eoCollapseSubtreeMutation eoGpMutate.h gp/eoGpMutate.h
+ */
+
+template<class FType, class Node>
+class eoCollapseSubtreeMutation: public eoMonOp< eoParseTree<FType, Node> >
+{
+public:
+
+  typedef eoParseTree<FType, Node> EoType;
+  /**
+   * Constructor
+   * @param _init An instantiation of eoGpDepthInitializer
+   * @param _max_length the maximum size of an individual
+   */
+  eoCollapseSubtreeMutation(eoInit<EoType>& _init, unsigned _max_length)
+    : eoMonOp<EoType>(), max_length(_max_length), initializer(_init)
+  {};
+
+  /// The class name
+  virtual string className() const { return "eoCollapseSubtreeMutation"; };
+
+  /// Dtor
+  virtual ~eoCollapseSubtreeMutation() {};
+  /**
+   * Mutate an individual
+   * @param _eo1 The individual that is to be changed
+   */
+  bool operator()(EoType& _eo1 )
+  {
+	  int i = rng.random(_eo1.size());
+	  // look for a subtree
+          while ((_eo1[i].arity() == 0) && (_eo1.size() > 1))
+	  {
+	  	i= rng.random(_eo1.size());
+	  };
+	
+	  // create a new tree to
+      	  EoType eo2;
+      	  initializer(eo2);
+	  
+	  int j = rng.random(eo2.size());
+	  // make sure we select a subtree (and not a terminal)
+	  while(eo2[j].arity() != 0)
+	  {
+	  	j = rng.random(eo2.size());
+	  };
+
+	  _eo1[i] = eo2[j]; // insert subtree
+	  
+	  // we don't have to prune because the subtree is always smaller
+	  _eo1.pruneTree(max_length);
+	
+    return true;
+  }
+
+private :
+
+  unsigned max_length;
+  eoInit<EoType>& initializer;
+};
+
+
+
+
+
+/** eoHoist -->  replace the individual with one of its subtree's 
+\class eoHoist eoGpMutate.h gp/eoGpMutate.h
+ */
+ 
+template<class FType, class Node>
+class eoHoistMutation: public eoMonOp< eoParseTree<FType, Node> >
+{
+public:
+
+  typedef eoParseTree<FType, Node> EoType;
+  /**
+   * Constructor
+   */
+  eoHoistMutation()
+    : eoMonOp<EoType>()
+  {};
+  
+  /// The class name
+  virtual string className() const { return "eoHoistMutation"; };
+
+  /// Dtor
+  virtual ~eoHoistMutation() {};
+  /**
+   * Mutate an individual
+   * @param _eo1 The individual that is to be changed
+   */
+  bool operator()(EoType& _eo1 )
+  {
+	
+	  
+	  // select a hoist point
+	  int i = rng.random(_eo1.size());
+      	  // and create a new tree
+	  EoType eo2(_eo1[i]);
+	  
+	  // we don't have to prune because the new tree is always smaller
+	  //_eo1.pruneTree(max_length);
+	  
+	  _eo1 = eo2;
+
+    return true;
+  }
+
+private :
+
+};
+
+
+#endif