code: ///////////////////////////////////////////////////////////////////////////////
  // For information as to what this class does, see the Javadoc, below.       //
  // Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006,       //
  // 2007, 2008, 2009, 2010, 2014, 2015 by Peter Spirtes, Richard Scheines, Joseph   //
  // Ramsey, and Clark Glymour.                                                //
  //                                                                           //
  // 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 2 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, write to the Free Software               //
  // Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA //
  ///////////////////////////////////////////////////////////////////////////////
  
  package edu.cmu.tetrad.search.mb;
  
  import edu.cmu.tetrad.graph.Node;
  import edu.cmu.tetrad.search.IndependenceTest;
  import edu.cmu.tetrad.search.MbSearch;
  
  import java.util.LinkedList;
  import java.util.List;
  
  /**
   * Implements IAMB.
   */
  public class Iamb implements MbSearch {
  
      /**
       * The independence test used to perform the search.
       */
      private IndependenceTest independenceTest;
  
      /**
       * The list of variables being searched over. Must contain the target.
       */
      private List<Node> variables;
  
      /**
       * Constructs a new search.
       *
       * @param test The source of conditional independence information for the search.
       */
      public Iamb(IndependenceTest test) {
          if (test == null) {
              throw new NullPointerException();
          }
  
          this.independenceTest = test;
          this.variables = test.getVariables();
      }
  
      public List<Node> findMb(String targetName) {
          Node target = getVariableForName(targetName);
          List<Node> cmb = new LinkedList<>();
          boolean cont = true;
  
          // Forward phase.
          while (cont) {
              cont = false;
  
              List<Node> remaining = new LinkedList<>(variables);
              remaining.removeAll(cmb);
              remaining.remove(target);
  
              double strength = Double.NEGATIVE_INFINITY;
              Node f = null;
  
              for (Node v : remaining) {
                  double _strength = associationStrength(v, target, cmb);
  
                  if (_strength > strength) {
                      strength = _strength;
                      f = v;
                  }
              }
  
              if (f == null) {
                  break;
              }
  
              if (!independenceTest.isIndependent(f, target, cmb)) {
                  cmb.add(f);
                  cont = true;
              }
          }
  
          // Backward phase.
  
          for (Node f : new LinkedList<>(cmb)) {
              cmb.remove(f);
  
              if (independenceTest.isIndependent(f, target, cmb)) {
                  continue;
              }
  
              cmb.add(f);
          }
  
  //        boolean changed = true;
  //
  //        while (changed) {
  //            changed = false;
  //
  //            for (Node node : new LinkedList<Node>(cmb)) {
  //                cmb.remove(node);
  //
  //                if (independenceTest.isIndependent(node, target, cmb)) {
  //                    changed = true;
  //                    continue;
  //                }
  //
  //                cmb.add(node);
  //            }
  //        }
  
          return cmb;
      }
  
      private double associationStrength(Node v, Node target, List<Node> cmb) {
          independenceTest.isIndependent(v, target, cmb);
          return 1.0 - independenceTest.getPValue();
      }
  
      public String getAlgorithmName() {
          return "IAMB";
      }
  
      public int getNumIndependenceTests() {
          return 0;
      }
  
      private Node getVariableForName(String targetName) {
          Node target = null;
  
          for (Node V : variables) {
              if (V.getName().equals(targetName)) {
                  target = V;
                  break;
              }
          }
  
          if (target == null) {
              throw new IllegalArgumentException(
                      "Target variable not in dataset: " + targetName);
          }
  
          return target;
      }
  }
  
  
  
  