# eoProportionalSelect.h

    00001 // -*- mode: c++; c-indent-level: 4; c++-member-init-indent: 8; comment-column: 35; -*-
    00002
    00003 //-----------------------------------------------------------------------------
    00004 // eoProportionalSelect.h
    00005 // (c) GeNeura Team, 1998 - EEAAX 1999, Maarten Keijzer 2000
    00006 /*
    00007     This library is free software; you can redistribute it and/or
    00008     modify it under the terms of the GNU Lesser General Public
    00009     License as published by the Free Software Foundation; either
    00010     version 2 of the License, or (at your option) any later version.
    00011
    00012     This library is distributed in the hope that it will be useful,
    00013     but WITHOUT ANY WARRANTY; without even the implied warranty of
    00014     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    00015     Lesser General Public License for more details.
    00016
    00017     You should have received a copy of the GNU Lesser General Public
    00018     License along with this library; if not, write to the Free Software
    00019     Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
    00020
    00021     Contact: todos@geneura.ugr.es, http://geneura.ugr.es
    00022              Marc.Schoenauer@polytechnique.fr
    00023              mak@dhi.dk
    00024  */
    00025 //-----------------------------------------------------------------------------
    00026
    00027 #ifndef eoProportionalSelect_h
    00028 #define eoProportionalSelect_h
    00029
    00030 //-----------------------------------------------------------------------------
    00031
    00032 #include <utils/eoRNG.h>
    00033 #include <utils/selectors.h>
    00034 #include <eoSelectOne.h>
    00035 #include <eoPop.h>
    00036 //-----------------------------------------------------------------------------
    00043 //-----------------------------------------------------------------------------
    00044
    00045 template <class EOT> class eoProportionalSelect: public eoSelectOne<EOT>
    00046 {
    00047 public:
    00049   eoProportionalSelect(const eoPop<EOT>& pop = eoPop<EOT>())
    00050   {
    00051     if (minimizing_fitness<EOT>())
    00052       throw std::logic_error("eoProportionalSelect: minimizing fitness");
    00053   }
    00054
    00055   void setup(const eoPop<EOT>& _pop)
    00056   {
    00057       if (_pop.size() == 0) return;
    00058
    00059       cumulative.resize(_pop.size());
    00060       cumulative[0] = _pop[0].fitness();
    00061
    00062       for (unsigned i = 1; i < _pop.size(); ++i)
    00063       {
    00064           cumulative[i] = _pop[i].fitness() + cumulative[i-1];
    00065       }
    00066   }
    00067
    00070   const EOT& operator()(const eoPop<EOT>& _pop)
    00071   {
    00072       if (cumulative.size() == 0) setup(_pop);
    00073
    00074       double fortune = rng.uniform() * cumulative.back();
    00075       typename FitVec::iterator result = std::upper_bound(cumulative.begin(), cumulative.end(), fortune);
    00076       return _pop[result - cumulative.begin()];
    00077   }
    00078
    00079 private :
    00080
    00081   typedef std::vector<typename EOT::Fitness> FitVec;
    00082   FitVec cumulative;
    00083 };
    00084
    00085 #endif