content: /* 
   * Copyright (C) 2015 Adrien Guille <adrien.guille@univ-lyon2.fr>
   *
   * This program 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.
   *
   * This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.
   */
  package main.java.fr.ericlab.sondy.algo.influenceanalysis;
  
  import main.java.fr.ericlab.sondy.algo.Parameter;
  import main.java.fr.ericlab.sondy.core.app.AppParameters;
  import org.graphstream.graph.Node;
  
  /**
   *
   *   @author Adrien GUILLE, ERIC Lab, University of Lyon 2
   *   @email adrien.guille@univ-lyon2.fr
   */
  public class PageRank extends InfluenceAnalysisMethod {
      double dampingFactor = 0.15;
      double rankCoefficient = 3;
  
      public PageRank(){
          super();
          parameters.add(new Parameter("dampingFactor",dampingFactor+""));
          parameters.add(new Parameter("rankCoefficient",rankCoefficient+""));
      }
      
      @Override
      public String getName() {
          return "Page Rank";
      }
  
      @Override
      public String getCitation() {
          return "<li><b>Page-Rank:</b> L. Page, S. Brin, R. Motwani, and T. Winograd (1998) The pagerank citation ranking: Bringing order to the web, In Proceedings of the 1998 ACM International World Wide Web Conference, pp. 161–172</li>";
      }
  
      @Override
      public String getDescription() {
          return "Computes the probability that a 'random surfer' visits each node to estimate how important users are";
      }
  
      @Override
      public void apply() {
          dampingFactor = parameters.getParameterValue("dampingFactor");
          rankCoefficient = parameters.getParameterValue("rankCoefficient");
          org.graphstream.algorithm.PageRank pageRank = new org.graphstream.algorithm.PageRank();
          pageRank.setDampingFactor(dampingFactor);
          pageRank.init(AppParameters.authorNetwork);
          pageRank.compute();
          int nbNodes = AppParameters.authorNetwork.getNodeCount();
          for (Node node : AppParameters.authorNetwork) {
              double rank = pageRank.getRank(node);
              rankedUsers.add(node.getId(),(int)(rank*nbNodes*rankCoefficient));
          }
      }
  
  }
  