/* ===========================================================

 * JFreeChart : a free chart library for the Java(tm) platform

 * ===========================================================

 *

 * (C) Copyright 2000-2004, by Object Refinery Limited and Contributors.

 *

 * Project Info:  http://www.jfree.org/jfreechart/index.html

 *

 * This library is free software; you can redistribute it and/or modify it under the terms

 * of the GNU Lesser General Public License as published by the Free Software Foundation;

 * either version 2.1 of the License, or (at your option) any later version.

 *

 * This library 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 Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public License along with this

 * library; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330,

 * Boston, MA 02111-1307, USA.

 *

 * [Java is a trademark or registered trademark of Sun Microsystems, Inc. 

 * in the United States and other countries.]

 *

 * ------------------

 * DataUtilities.java

 * ------------------

 * (C) Copyright 2003, 2004, by Object Refinery Limited.

 *

 * Original Author:  David Gilbert (for Object Refinery Limited);

 * Contributor(s):   -;

 *

 * $Id: DataUtilities.java,v 1.1 2004/08/31 15:27:03 mungady Exp $

 *

 * Changes

 * -------

 * 05-Mar-2003 : Version 1 (DG);

 *

 */



package org.jfree.data.general;



import org.jfree.data.DefaultKeyedValues;

import org.jfree.data.KeyedValues;



/**

 * Utility methods for use with some of the data classes (but not the datasets, see

 * {@link DatasetUtilities}).

 */

public abstract class DataUtilities {



    /**

     * Returns a {@link KeyedValues} instance that contains the cumulative percentage values

     * for the data in another {@link KeyedValues} instance.

     * <p>

     * The percentages are values between 0.0 and 1.0 (where 1.0 = 100%).

     *

     * @param data  the data.

     *

     * @return The cumulative percentages.

     */

    public static KeyedValues getCumulativePercentages(KeyedValues data) {



        final DefaultKeyedValues result = new DefaultKeyedValues();



        double total = 0.0;

        for (int i = 0; i < data.getItemCount(); i++) {

            final Number v = data.getValue(i);

            if (v != null) {

                total = total + v.doubleValue();

            }

        }



        double runningTotal = 0.0;

        for (int i = 0; i < data.getItemCount(); i++) {

            final Number v = data.getValue(i);

            if (v != null) {

                runningTotal = runningTotal + v.doubleValue();

            }

            result.addValue(data.getKey(i), new Double(runningTotal / total));

        }



        return result;



    }



}

