goodnesslandscape.java

用于求解TSP(Traveling salesman problem

/**
 * Description: The goodness landscape.
 *
 * @ Author        Create/Modi     Note
 * Xiaofeng Xie    Jul 12, 2006
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * Please acknowledge the author(s) if you use this code in any way.
 *
 * @version 1.0
 * @Since SWAF1.0
 */
package implement.TSP.represent;

import maosKernel.represent.*;
import maosKernel.represent.space.*;
import maosKernel.represent.encode.iEncode.*;

public class GoodnessLandscape extends AbsILandscape implements IGetGlobalCostEngine {
  protected IGetProblemDataEngine dataStorager = null;

  public GoodnessLandscape(RealProblemData problemData) {
    super(problemData);
    this.dataStorager = problemData;
  }

  public IGetProblemDataEngine getIGetProblemDataEngine() {
    return dataStorager;
  }

  protected AbsSearchSpace initSearchSpace(AbsProblemData problemData) {
    return new SearchSpace(problemData.getNodeNumber());
  }

  public int getGlobalCost(SearchState state) {
    int[] permutations = state.getIArray();
    int totalLength = dataStorager.getLocalCost(permutations[permutations.length-1], permutations[0]);
    for (int i=1; i<permutations.length; i++) {
      totalLength += dataStorager.getLocalCost(permutations[i-1], permutations[i]);
    }
    return totalLength;
  }
}