80 lines
2.2 KiB
Java
80 lines
2.2 KiB
Java
//******************************************************************************
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//
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// File: DoublePrng.java
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// Package: edu.rit.numeric
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// Unit: Class edu.rit.numeric.DoublePrng
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//
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// This Java source file is copyright (C) 2013 by Alan Kaminsky. All rights
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// reserved. For further information, contact the author, Alan Kaminsky, at
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// ark@cs.rit.edu.
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//
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// This Java source file is part of the Parallel Java 2 Library ("PJ2"). PJ2 is
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// free software; you can redistribute it and/or modify it under the terms of
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// the GNU General Public License as published by the Free Software Foundation;
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// either version 3 of the License, or (at your option) any later version.
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//
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// PJ2 is distributed in the hope that it will be useful, but WITHOUT ANY
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// WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
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// A PARTICULAR PURPOSE. See the GNU General Public License for more details.
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//
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// A copy of the GNU General Public License is provided in the file gpl.txt. You
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// may also obtain a copy of the GNU General Public License on the World Wide
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// Web at http://www.gnu.org/licenses/gpl.html.
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//
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//******************************************************************************
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package edu.rit.numeric;
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import edu.rit.util.Random;
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/**
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* Class DoublePrng is the abstract base class for a pseudorandom number
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* generator (PRNG) that generates random numbers of type <TT>double</TT>. The
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* generated random numbers' probability distribution is determined by the
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* subclass.
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*
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* @author Alan Kaminsky
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* @version 10-Jun-2008
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*/
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public abstract class DoublePrng
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{
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// Hidden data members.
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/**
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* The underlying uniform PRNG.
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*/
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protected final Random myUniformPrng;
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// Exported constructors.
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/**
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* Construct a new double PRNG.
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*
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* @param theUniformPrng The underlying uniform PRNG.
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*
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* @exception NullPointerException
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* (unchecked exception) Thrown if <TT>theUniformPrng</TT> is null.
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*/
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public DoublePrng
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(Random theUniformPrng)
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{
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if (theUniformPrng == null)
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{
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throw new NullPointerException
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("DoublePrng(): theUniformPrng is null");
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}
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myUniformPrng = theUniformPrng;
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}
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// Exported operations.
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/**
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* Returns the next random number.
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*
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* @return Random number.
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*/
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public abstract double next();
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}
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