source: branches/LearningClassifierSystems/HeuristicLab.Encodings.VariableVector/3.3/Variable/DoubleVariable.cs @ 9392

#region License Information
/* HeuristicLab
 * Copyright (C) 2002-2012 Heuristic and Evolutionary Algorithms Laboratory (HEAL)
 *
 * This file is part of HeuristicLab.
 *
 * HeuristicLab 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.
 *
 * HeuristicLab 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 HeuristicLab. If not, see <http://www.gnu.org/licenses/>.
 */
#endregion

using System;
using System.Collections.Generic;
using System.Linq;
using HeuristicLab.Common;
using HeuristicLab.Core;
using HeuristicLab.Persistence.Default.CompositeSerializers.Storable;

namespace HeuristicLab.Encodings.VariableVector {
  [StorableClass]
  [Item(Name = "DoubleVariable", Description = "")]
  public class DoubleVariable : Variable<double> {
    public override int VirtualLength {
      get { return 2; }
    }

    [Storable]
    protected double min;
    public double Min {
      get { return min; }
    }
    [Storable]
    protected double max;
    public double Max {
      get { return max; }
    }

    [Storable]
    protected double currentCenter;
    public double CurrentCenter {
      get { return currentCenter; }
      set { currentCenter = value; }
    }

    [Storable]
    protected double currentSpread;
    public double CurrentSpread {
      get { return currentSpread; }
      set { currentSpread = value; }
    }

    [StorableConstructor]
    protected DoubleVariable(bool deserializing) : base(deserializing) { }
    protected DoubleVariable(DoubleVariable original, Cloner cloner)
      : base(original, cloner) {
      min = original.min;
      max = original.max;
      currentSpread = original.currentSpread;
      currentCenter = original.currentCenter;
    }
    public DoubleVariable() : base() { }
    public DoubleVariable(string variableName, IEnumerable<double> variableValues)
      : base(variableName) {
      min = variableValues.Min();
      max = variableValues.Max();
    }
    protected DoubleVariable(string variableName, double min, double max)
      : base(variableName) {
      this.min = min;
      this.max = max;
    }
    public DoubleVariable(string variableName, IEnumerable<double> variableValues, double center, double spread)
      : this(variableName, variableValues) {
      CurrentCenter = center;
      CurrentSpread = spread;
    }

    public override IDeepCloneable Clone(Cloner cloner) {
      return new DoubleVariable(this, cloner);
    }

    public override string ToString() {
      return (currentCenter - currentSpread) + " - " + (currentCenter + currentSpread);
    }

    public override bool MatchInput(string target) {
      return Match(Double.Parse(target));
    }

    public override bool Match(double target) {
      return currentCenter - currentSpread <= target && target <= currentCenter + currentSpread;
    }

    public override IVariable GetEmptyCopy() {
      return new DoubleVariable(variableName, min, max);
    }
    public override IVariable GetSetCopy() {
      DoubleVariable copy = (DoubleVariable)GetEmptyCopy();
      copy.CurrentCenter = this.CurrentCenter;
      copy.CurrentSpread = this.CurrentSpread;
      return copy;
    }

    // Important! If this mehtod is called instead of the more concrete "Randomize(IRandom random, double spreadPercentage)"
    // spread percentage is 50%
    public override void Randomize(IRandom random) {
      Randomize(random, 50);
    }

    public void Randomize(IRandom random, double spreadPercentage) {
      if (spreadPercentage < 0 || spreadPercentage > 100) {
        throw new ArgumentException("Spread percentage has to be between 0 and 100.");
      }
      double delta = Max - Min;
      CurrentCenter = random.NextDouble() * delta + Min;
      CurrentSpread = random.NextDouble() * (delta * (spreadPercentage / 100));
    }

    public override bool Identical(IVariable target) {
      var targetCast = target as DoubleVariable;
      if (targetCast == null) { return false; }
      if (variableName != targetCast.variableName || !currentCenter.IsAlmost(targetCast.currentCenter)
        || !currentSpread.IsAlmost(targetCast.currentSpread) || !max.IsAlmost(targetCast.max)
        || !min.IsAlmost(targetCast.min)) { return false; }

      return true;
    }

    public override double GetGenerality() {
      double delta = max - min;
      double intervalInBoundsWidth = Math.Min(max, currentCenter + currentSpread) - Math.Max(min, currentCenter - currentSpread);
      double generality = intervalInBoundsWidth / delta;
      return generality > 1 ? 1 : generality;
    }

    public override bool IsGreaterThanOrEquallyGeneral(IVariable target) {
      var targetCast = target as DoubleVariable;
      if (targetCast == null) { return false; }
      return currentCenter - currentSpread < targetCast.currentCenter - targetCast.currentSpread
        && currentCenter + currentSpread > targetCast.currentCenter + targetCast.currentSpread;
    }

    public override IVariable CrossParentsAtPosition(IVariable parent2, int pos) {
      DoubleVariable parent2Cast = parent2 as DoubleVariable;
      if (parent2Cast == null) { throw new ArgumentException("Argument is not of the correct type."); }
      if (pos > 1 || pos < 0) { throw new ArgumentOutOfRangeException(); }
      DoubleVariable crossed = (DoubleVariable)this.GetSetCopy();
      if (pos == 1) {
        crossed.CurrentSpread = parent2Cast.CurrentSpread;
      }
      return crossed;
    }

    public override void Manipulate(IRandom random, string stringValue, int pos) {
      if (pos > 1 || pos < 0) { throw new ArgumentOutOfRangeException(); }
      Manipulate(random, pos, 10);
    }

    public void Manipulate(IRandom random, int pos, double percentage) {
      if (pos > 1 || pos < 0) { throw new ArgumentOutOfRangeException(); }
      double delta = max - min;
      double maxChange = delta * (percentage / 100);
      double actualChange = (random.NextDouble() * maxChange * 2) - maxChange;
      if (pos == 0) {
        currentCenter += actualChange;
      } else if (pos == 1) {
        currentSpread += actualChange;
        //otherwise the interval could be corrupt and no input could match the rule.
        currentSpread = currentSpread > 0 ? currentSpread : 0;
      }
    }

    public override void Cover(IRandom random, string stringValue, double changeSymbolProbability) {
      CoverWithSpreadPercentage(random, stringValue, changeSymbolProbability);
    }

    public void CoverWithSpreadPercentage(IRandom random, string stringValue, double spreadPercentage) {
      currentCenter = double.Parse(stringValue);
      double delta = max - min;
      currentSpread = random.NextDouble() * (delta * spreadPercentage);
    }
  }
}