source: stable/HeuristicLab.Optimization.Operators/3.3/ParentCopyCrossover.cs

#region License Information
/* HeuristicLab
 * Copyright (C) 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 HeuristicLab.Common;
using HeuristicLab.Core;
using HeuristicLab.Operators;
using HeuristicLab.Parameters;
using HEAL.Attic;

namespace HeuristicLab.Optimization.Operators {
  [Item("ParentCopyCrossover", "This operator creates an offspring by creating a clone of a randomly chosen parent. It can be used in situations where no crossover should occur after selection.")]
  [StorableType("B97DCEBA-B631-4D12-997A-665C33B86C70")]
  public class ParentCopyCrossover : InstrumentedOperator, ICrossover, IStochasticOperator {
    public ILookupParameter<IRandom> RandomParameter {
      get { return (ILookupParameter<IRandom>)Parameters["Random"]; }
    }


    [StorableConstructor]
    protected ParentCopyCrossover(StorableConstructorFlag _) : base(_) { }
    protected ParentCopyCrossover(ParentCopyCrossover original, Cloner cloner) : base(original, cloner) { }
    public ParentCopyCrossover()
      : base() {
      Parameters.Add(new LookupParameter<IRandom>("Random", "The random number generator."));
    }

    public override IOperation InstrumentedApply() {
      IScope scope = ExecutionContext.Scope;
      int index = RandomParameter.ActualValue.Next(scope.SubScopes.Count);
      IScope child = scope.SubScopes[index];

      foreach (IVariable var in child.Variables)
        scope.Variables.Add((IVariable)var.Clone());

      return base.InstrumentedApply();
    }

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