gpgenotype.java

一个开源的用java开发的遗传算法的封装好的工程

      // Increase number of generation.
      // ------------------------------
      conf.incrementGenerationNr();
      // Fire an event to indicate we've performed an evolution.
      // -------------------------------------------------------
      conf.getEventManager().fireGeneticEvent(
          new GeneticEvent(GeneticEvent.GPGENOTYPE_EVOLVED_EVENT, this));
    } catch (InvalidConfigurationException iex) {
      // This should never happen.
      // -------------------------
      throw new IllegalStateException(iex.getMessage());
    }
  }

  public GPPopulation getGPPopulation() {
    return m_population;
  }

  /**
   * @return the total fitness, that is the fitness over all chromosomes
   *
   * @author Klaus Meffert
   * @since 3.0
   */
  public double getTotalFitness() {
    return m_totalFitness;
  }

  /**
   * Default implementation of method to run GPGenotype as a thread.
   *
   * @author Klaus Meffert
   * @since 3.0
   */
  public void run() {
    try {
      while (!Thread.currentThread().interrupted()) {
        evolve();
        calcFitness();
        // Pause between evolutions to avoid 100% CPU load.
        // ------------------------------------------------
        Thread.sleep(10);
      }
    } catch (Exception ex) {
      ex.printStackTrace();
      System.exit(1);
    }
  }

  /**
   * Retrieves the GPProgram in the population with the highest fitness
   * value.
   *
   * @return the GPProgram with the highest fitness value, or null if there
   * are no programs in this Genotype
   *
   * @author Klaus Meffert
   * @since 3.0
   */
  public synchronized IGPProgram getFittestProgram() {
    double fittest;
    if (m_allTimeBest != null) {
      fittest = m_allTimeBest.getFitnessValue();
    }
    else {
      fittest = FitnessFunction.NO_FITNESS_VALUE;
    }
    IGPProgram fittestPop = getGPPopulation().determineFittestProgram();
    if (fittestPop == null) {
      return m_allTimeBest;
    }
    if (getGPConfiguration().getGPFitnessEvaluator().isFitter(fittest,
        fittestPop.getFitnessValue())) {
      return m_allTimeBest;
    }
    else {
//      m_allTimeBest = fittestPop;/**@todo*/
      return fittestPop;
    }
  }
  /**
   * Retrieves the GPProgram in the population with the highest fitness
   * value. Only considers programs for which the fitness value has already
   * been computed.
   *
   * @return the GPProgram with the highest fitness value, or null if there
   * are no programs with known fitness value in this Genotype
   *
   * @author Klaus Meffert
   * @since 3.2
   */
  public synchronized IGPProgram getFittestProgramComputed() {
    return getGPPopulation().determineFittestProgramComputed();
  }

  protected void setGPPopulation(GPPopulation a_pop) {
    m_population = a_pop;
  }

  /**
   * Sets the configuration to use with the Genetic Algorithm.
   * @param a_configuration the configuration to use
   *
   * @author Klaus Meffert
   * @since 3.0
   */
  public void setGPConfiguration(GPConfiguration a_configuration) {
    m_configuration = a_configuration;
  }

  /**
   * Compares this entity against the specified object.
   *
   * @param a_other the object to compare against
   * @return true: if the objects are the same, false otherwise
   *
   * @author Klaus Meffert
   * @since 3.0
   */
  public boolean equals(Object a_other) {
    try {
      return compareTo(a_other) == 0;
    } catch (ClassCastException cex) {
      return false;
    }
  }

  /**
   * Compares this Genotype against the specified object. The result is true
   * if the argument is an instance of the Genotype class, has exactly the
   * same number of programs as the given Genotype, and, for each
   * GPProgram in this Genotype, there is an equal program in the
   * given Genotype. The programs do not need to appear in the same order
   * within the populations.
   *
   * @param a_other the object to compare against
   * @return a negative number if this genotype is "less than" the given
   * genotype, zero if they are equal to each other, and a positive number if
   * this genotype is "greater than" the given genotype
   *
   * @author Klaus Meffert
   * @since 3.0
   */
  public int compareTo(Object a_other) {
    try {
      // First, if the other Genotype is null, then they're not equal.
      // -------------------------------------------------------------
      if (a_other == null) {
        return 1;
      }
      GPGenotype otherGenotype = (GPGenotype) a_other;
      // First, make sure the other Genotype has the same number of
      // chromosomes as this one.
      // ----------------------------------------------------------
      int size1 = getGPPopulation().size();
      int size2 = otherGenotype.getGPPopulation().size();
      if (size1 != size2) {
        if (size1 > size2) {
          return 1;
        }
        else {
          return -1;
        }
      }
      // Next, prepare to compare the programs of the other Genotype
      // against the programs of this Genotype. To make this a lot
      // simpler, we first sort the programs in both this Genotype
      // and the one we're comparing against. This won't affect the
      // genetic algorithm (it doesn't care about the order), but makes
      // it much easier to perform the comparison here.
      // --------------------------------------------------------------
      Arrays.sort(getGPPopulation().getGPPrograms());
      Arrays.sort(otherGenotype.getGPPopulation().getGPPrograms());
      for (int i = 0; i < getGPPopulation().size(); i++) {
        int result = (getGPPopulation().getGPProgram(i).compareTo(
            otherGenotype.getGPPopulation().getGPProgram(i)));
        if (result != 0) {
          return result;
        }
      }
      return 0;
    } catch (ClassCastException e) {
      return -1;
    }
  }

  /***
   * Hashcode function for the genotype, tries to create a unique hashcode for
   * the chromosomes within the population. The logic for the hashcode is
   *
   * Step  Result
   * ----  ------
   *    1  31*0      + hashcode_0 = y(1)
   *    2  31*y(1)   + hashcode_1 = y(2)
   *    3  31*y(2)   + hashcode_2 = y(3)
   *    n  31*y(n-1) + hashcode_n-1 = y(n)
   *
   * Each hashcode is a number and the binary equivalent is computed and
   * returned.
   * @return the computed hashcode
   *
   * @author Klaus Meffert
   * @since 3.0
   */
  public int hashCode() {
    int i, size = getGPPopulation().size();
    IGPProgram prog;
    int twopower = 1;
    // For empty genotype we want a special value different from other hashcode
    // implementations.
    // ------------------------------------------------------------------------
    int localHashCode = -573;
    for (i = 0; i < size; i++, twopower = 2 * twopower) {
      prog = getGPPopulation().getGPProgram(i);
      localHashCode = 31 * localHashCode + prog.hashCode();
    }
    return localHashCode;
  }

  /**
   * @param a_verbose true: output status information to console
   *
   * @author Klaus Meffert
   * @since 3.0
   */
  public void setVerboseOutput(boolean a_verbose) {
    m_verbose = a_verbose;
  }

  private IGPProgram cloneProgram(IGPProgram a_original) {
    IGPProgram validProgram = getGPConfiguration().
        getPrototypeProgram();
    ICloneHandler cloner = getGPConfiguration().getJGAPFactory().
        getCloneHandlerFor(validProgram, null);
    if (cloner != null) {
      try {
        IGPProgram program = (IGPProgram) cloner.perform(
            validProgram, null, null);
        return program;
      } catch (Exception ex) {
        return null;
      }
    }
    return null;
  }

  /**
   * Stores a Variable.
   *
   * @param a_var the Variable to store
   *
   * @author Klaus Meffert
   * @since 3.2
   */
  public void putVariable(Variable a_var) {
    m_variables.put(a_var.getName(), a_var);
  }

  /**
   * @param a_varName name of variable to retriebe
   * @return Variable instance or null, if not found
   *
   * @author Klaus Meffert
   * @since 3.2
   */
  public Variable getVariable(String a_varName) {
    return (Variable) m_variables.get(a_varName);
  }

  /**
   * Adds a GP program to this Genotype. Does nothing when given null.
   * The injection is actually executed in method create(..) of GPPopulation.
   *
   * @param a_toAdd the program to add
   *
   * @author Klaus Meffert
   * @since 3.2
   */
  public void addFittestProgram(final IGPProgram a_toAdd) {
    if (a_toAdd != null) {
      m_fittestToAdd = a_toAdd;
    }
  }

  /**
   * Fills up the population with random programs if necessary.
   *
   * @param a_num the number of programs to add
   * @throws InvalidConfigurationException
   *
   * @author Klaus Meffert
   * @since 3.2
   */
  public void fillPopulation(final int a_num)
      throws InvalidConfigurationException {
    IGPProgram sampleProg = getGPConfiguration().getPrototypeProgram();
    if (sampleProg == null) {
      /**@todo care about*/
    }
    Class sampleClass = sampleProg.getClass();
    IInitializer chromIniter = getGPConfiguration().getJGAPFactory().
        getInitializerFor(sampleProg, sampleClass);
    if (chromIniter == null) {
      throw new InvalidConfigurationException("No initializer found for class "
                                              + sampleClass);
    }
    try {
      for (int i = 0; i < a_num; i++) {
        /**@todo implement*/
//        getGPPopulation().addChromosome( (IChromosome) chromIniter.perform(sampleProg,
//            sampleClass, null));
      }
    }
    catch (Exception ex) {
      // Try to propagate exception, see "bug" 1661635.
      // ----------------------------------------------
      if (ex.getCause() != null) {
        throw new IllegalStateException(ex.getCause().toString());
      }
      else {
        throw new IllegalStateException(ex.getMessage());
      }
    }

  }

}