/*
 * Copyright (c) 2005, Regents of the University of California
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * * Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 *
 * * Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in
 *   the documentation and/or other materials provided with the
 *   distribution.  
 *
 * * Neither the name of the University of California, Berkeley nor
 *   the names of its contributors may be used to endorse or promote
 *   products derived from this software without specific prior 
 *   written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
 * OF THE POSSIBILITY OF SUCH DAMAGE.
 */

package blog.distrib;

import blog.*;
import java.util.*;
import common.Util;

public class BinaryBernoulliDistrib extends AbstractCondProbDistrib {
 
    public BinaryBernoulliDistrib( List params ){
	if (params.size() != 1) {
	    throw new IllegalArgumentException
		("Binary Bernoulli distribution requires exactly one parameter, " 
		 + "not " + params.size() + ".");
	}
	Object param_obj = params.get(0);
	if (!(param_obj instanceof Number)) {
	    throw new IllegalArgumentException
		("Parameter to Binary Bernoulli distrib must be of class Number, " 
		 + "not " + param_obj.getClass() + ".");
	}
		
	pi = ((Number) param_obj).doubleValue();
	if ((pi < 0) || (pi > 1)) {
	    throw new IllegalArgumentException
		("Parameter to Binary Bernoulli must be in interval [0, 1], not " 
		 + pi + ".");
	}
    }

    public double getProb( List args, Object value ) {
	if (args.size() != 0) {
	    throw new IllegalArgumentException
		("Binary Bernoulli distribution takes zero arguments, not "
		 + args.size() + ".");
	}
	if (!(value instanceof Integer)) {
	    throw new IllegalArgumentException
		("Binary Bernoulli distribution is over objects of class Integer, "
		 + "not " + value.getClass() + ".");
	}

	int int_value = ((Integer) value).intValue();

	if (!((int_value == 0) || (int_value == 1))){
	    throw new IllegalArgumentException
		("Binary Bernoulli distribution is over the set {0,1}; passed value: "
		 + value.getClass() + ".");

	}

	if (int_value == 1) {
	    return pi;
	}
	return (1 - pi);
    }

    public Object sampleVal( List args, Type childType ) {
	if (args.size() != 0) {
	    throw new IllegalArgumentException
		("Binary Bernoulli distribution takes zero arguments, not "
		 + args.size() + ".");
	}

	if (Util.random() < pi) {
	    return new Integer(1);
	}
	return new Integer(0);
    }

    private double pi;   
   
}

This file was generated on Tue Jun 08 17:53:47 PDT 2010 from file BinaryBernoulliDistrib.java
by the ilog.language.tools.Hilite Java tool written by Hassan Aït-Kaci