source: branches/3.1/sources/HeuristicLab.SimOpt/NormalIntManipulator.cs @ 588

using System;
using System.Collections.Generic;
using System.Globalization;
using System.Linq;
using System.Text;
using System.Xml;
using HeuristicLab.Core;
using HeuristicLab.Data;
using HeuristicLab.Random;

namespace HeuristicLab.SimOpt {
  public class NormalIntManipulator : SimOptManipulationOperatorBase {
    public override string Description {
      get { return @"Perturbs an IntData or ConstrainedIntData by a value normally distributed around 0"; }
    }

    public NormalIntManipulator()
      : base() {
      AddVariableInfo(new VariableInfo("ShakingFactor", "Strength of the perturbation", typeof(DoubleData), VariableKind.In));
    }

    protected override void Apply(IScope scope, IRandom random, IItem item) {
      double shakingFactor = GetVariableValue<DoubleData>("ShakingFactor", scope, true).Data;
      NormalDistributedRandom normal = new NormalDistributedRandom(random, 0.0, shakingFactor);
      if (item is IntData) {
        ((IntData)item).Data += (int)normal.NextDouble();
        return;
      } else if (item is ConstrainedIntData) {
        ConstrainedIntData data = (item as ConstrainedIntData);
        for (int tries = 100; tries >= 0; tries--) {
          int newValue = data.Data + (int)normal.NextDouble();
          if (data.TrySetData(newValue)) return;
        }
        throw new InvalidProgramException("Coudn't find a valid value in 100 tries");
      } else throw new InvalidOperationException("ERROR: UniformIntManipulator does not know how to work with " + ((item != null) ? (item.GetType().ToString()) : ("null")) + " data");
    }
  }
}