content: /*
   *    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., 675 Mass Ave, Cambridge, MA 02139, USA.
   */
  
  /*
   *    ConditionalDensityEstimator.java
   *    Copyright (C) 2009 University of Waikato, Hamilton, New Zealand
   *
   */
  
  package weka.classifiers;
  
  import weka.core.Instance;
  
  /**
   * Interface for numeric prediction schemes that can output conditional
   * density estimates.
   *
   * @author Eibe Frank (eibe@cs.waikato.ac.nz)
   * @version $Revision: 6041 $
   */
  public interface ConditionalDensityEstimator {
  
    /**
     * Returns natural logarithm of density estimate for given value based on given instance.
     *
     * @param instance the instance to make the prediction for.
     * @param value the value to make the prediction for.
     * @return the natural logarithm of the density estimate
     * @exception Exception if the density cannot be computed
     */
    public double logDensity(Instance instance, double value) throws Exception;
  }
  
  