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.data;
  
  import edu.cmu.tetrad.graph.Node;
  import edu.cmu.tetrad.util.TetradSerializable;
  
  /**
   * <p>
   * Interface implemented by classes, instantiations of which can serve as data
   * models in Tetrad. Data models may be named if desired; if provided, these
   * names will be used for display purposes.</p>
   * <p>
   * This interface is relatively free of methods, mainly because classes that can
   * serve as data models in Tetrad are diverse, including continuous and discrete
   * data sets, covariance and correlation matrices, graphs, and lists of other
   * data models. So this is primarily a taqging interface.</p>
   *
   * @author Joseph Ramsey jdramsey@andrew.cmu.edu
   */
  public interface DataModel
          extends KnowledgeTransferable, VariableSource, TetradSerializable {
  
      long serialVersionUID = 23L;
  
      /**
       * @return the name of the data model (may be null).
       */
      String getName();
  
      /**
       * Sets the name of the data model (may be null).
       */
      void setName(String name);
  
      /**
       * Renders the data model as as String.
       */
      String toString();
  
      boolean isContinuous();
  
      boolean isDiscrete();
  
      boolean isMixed();
  
      Node getVariable(String name);
  
      DataModel copy();
  }
  