annotate src/population.hpp @ 0:add35537fdbb tip

Initial import

//  Copyright 2011, Ian Hobson.
//
//  This file is part of gpsynth.
//
//  gpsynth 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 3 of the License, or
//  (at your option) any later version.
//
//  gpsynth 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 gpsynth in the file COPYING. 
//  If not, see http://www.gnu.org/licenses/.

// Population class, manages a population of synth graphs and their evolution

// TODO - split out evolution behaviour in to a separate class, support
// multiple populations

#pragma once

#include "converter.hpp"
#include "evaluator.hpp"
#include "grammar.hpp"
#include "statistics.hpp"
#include "synth_graph.hpp"

#include "boost/function.hpp"

#include <string>
#include <vector>

typedef boost::function<bool (sg::Graph&)> MutationOperator;

class Population : public EvaluatorListenerInterface {
  std::vector<sg::Graph> population_;
  int best_fit_;
  std::vector<double> fitnesses_;
  // current generation
  int generation_;
  // total generations
  int max_generations_;
  int tournament_size_;
  double fitness_threshold_;
  double crossover_rate_;
  double mutation_rate_;
  bool reproduce_best_;
  bool keep_temp_folders_;
  GrammarInterface* grammar_;
  ConverterInterface* converter_;
  EvaluatorInterface* evaluator_;
  // work folder, where all files for current run are placed
  std::string work_folder_;
  // folder to write logs to
  std::string log_folder_;
  // folder to save best renders
  std::string render_folder_;
  // folder to save best dot scripts
  std::string dot_folder_;
  // folder to save exported graphs
  std::string export_folder_;
  // temp folder for current generation
  std::string generation_folder_;
  // available mutation operators
  std::vector<MutationOperator> mutators_;
  // selector for genetic operations
  stats::ProbabilitySelector genetic_operation_selector_;
  
  enum GeneticOperation {
    kCrossover,
    kMutation,
    kReproduction
  };
  
public:
  Population(GrammarInterface* grammar,
             ConverterInterface* converter,
             EvaluatorInterface* evaluator);
  
  void InitializePopulation(std::size_t size);
  void SetWorkFolder(const std::string& path);
  void SetFitnessThreshold(double value) { fitness_threshold_ = value; }
  void SetTournamentSize(int size) { tournament_size_ = size; }
  void Evolve(int generations);
  void ExportToDOT();
  void SetCrossoverRate(double rate);
  void SetMutationRate(double rate);
  void SetReproduceBest(bool value) { reproduce_best_ = value; }
  void SetKeepTempFolders(bool value) { keep_temp_folders_ = value; }
  
private:
  void EvaluateGeneration();
  void AnalyzeGeneration();
  void BreedNewGeneration();
  int SelectIndividual();
  void PerformCrossover(sg::Graph& child_1, sg::Graph& child_2);
  void PrepareNewChild(sg::Graph& child);
  void GraphRatedNotification(std::size_t graphs_rated);
  void SetupGeneticOperationSelector();
  void SaveGenerationBest();
  bool CheckThreshold() const;
  void CleanTempFolders() const;
  void NewGenerationMessage() const;
  void SetGenerationFolder();
};