//******************************************************************************
//
// File:    TransformedSeries.java
// Package: edu.rit.numeric
// Unit:    Class edu.rit.numeric.TransformedSeries
//
// This Java source file is copyright (C) 2007 by Alan Kaminsky. All rights
// reserved. For further information, contact the author, Alan Kaminsky, at
// ark@cs.rit.edu.
//
// This Java source file is part of the Parallel Java Library ("PJ"). PJ 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 3 of the License, or (at your option) any later version.
//
// PJ 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.
//
// A copy of the GNU General Public License is provided in the file gpl.txt. You
// may also obtain a copy of the GNU General Public License on the World Wide
// Web at http://www.gnu.org/licenses/gpl.html.
//
//******************************************************************************

package edu.rit.numeric;

/**
 * Class TransformedSeries provides a {@linkplain Series} that is formed by
 * transforming the values in an underlying {@linkplain Series}. The underlying
 * series consists of a list of values xi. The
 * transformed series consists of a list of values
 * f(xi), where f is computed by a {@link
 * Function Function}.
 *
 * @author  Alan Kaminsky
 * @version 27-Jul-2007
 */
public class TransformedSeries
	extends Series
	{

// Hidden data members.

	private Series mySeries;
	private Function myXFunction;

// Exported constructors.

	/**
	 * Construct a new transformed series.
	 *
	 * @param  theSeries     Underlying series.
	 * @param  theXFunction  Function for transforming the X values, or null not
	 *                       to transform the X values.
	 *
	 * @exception  NullPointerException
	 *     (unchecked exception) Thrown if theSeries is null.
	 */
	public TransformedSeries
		(Series theSeries,
		 Function theXFunction)
		{
		if (theSeries == null)
			{
			throw new NullPointerException
				("TransformedSeries(): theSeries is null");
			}
		mySeries = theSeries;
		myXFunction = theXFunction;
		}

// Exported operations.

	/**
	 * Returns the number of values in this series.
	 *
	 * @return  Length.
	 */
	public int length()
		{
		return mySeries.length();
		}

	/**
	 * Returns the given X value in this series.
	 *
	 * @param  i  Index.
	 *
	 * @return  The X value in this series at index i.
	 *
	 * @exception  ArrayIndexOutOfBoundsException
	 *     (unchecked exception) Thrown if i is not in the range
	 *     0 .. length()-1.
	 */
	public double x
		(int i)
		{
		double xval = mySeries.x(i);
		if (myXFunction != null) xval = myXFunction.f (xval);
		return xval;
		}

	}