001/* ===========================================================
002 * JFreeChart : a free chart library for the Java(tm) platform
003 * ===========================================================
004 *
005 * (C) Copyright 2000-2009, by Object Refinery Limited and Contributors.
006 *
007 * Project Info:  http://www.jfree.org/jfreechart/index.html
008 *
009 * This library is free software; you can redistribute it and/or modify it
010 * under the terms of the GNU Lesser General Public License as published by
011 * the Free Software Foundation; either version 2.1 of the License, or
012 * (at your option) any later version.
013 *
014 * This library is distributed in the hope that it will be useful, but
015 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
016 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
017 * License for more details.
018 *
019 * You should have received a copy of the GNU Lesser General Public
020 * License along with this library; if not, write to the Free Software
021 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
022 * USA.
023 *
024 * [Java is a trademark or registered trademark of Sun Microsystems, Inc.
025 * in the United States and other countries.]
026 *
027 * ---------------------
028 * HeatMapUtilities.java
029 * ---------------------
030 * (C) Copyright 2009, by Object Refinery Limited.
031 *
032 * Original Author:  David Gilbert (for Object Refinery Limited);
033 * Contributor(s):   -;
034 *
035 * Changes:
036 * --------
037 * 28-Jan-2009 : Version 1 (DG);
038 *
039 */
040
041package org.jfree.data.general;
042
043import java.awt.Graphics2D;
044import java.awt.Paint;
045import java.awt.image.BufferedImage;
046import org.jfree.chart.renderer.PaintScale;
047import org.jfree.data.xy.XYDataset;
048import org.jfree.data.xy.XYSeries;
049import org.jfree.data.xy.XYSeriesCollection;
050
051/**
052 * A utility class for the {@link HeatMapDataset}.
053 *
054 * @since 1.0.13
055 */
056public abstract class HeatMapUtilities {
057
058    /**
059     * Returns a dataset containing one series that holds a copy of the (x, z)
060     * data from one row (y-index) of the specified dataset.
061     *
062     * @param dataset  the dataset (<code>null</code> not permitted).
063     * @param row  the row (y) index.
064     * @param seriesName  the series name/key (<code>null</code> not permitted).
065     *
066     * @return The dataset.
067     */
068    public static XYDataset extractRowFromHeatMapDataset(HeatMapDataset dataset,
069            int row, Comparable seriesName) {
070        XYSeries series = new XYSeries(seriesName);
071        int cols = dataset.getXSampleCount();
072        for (int c = 0; c < cols; c++) {
073            series.add(dataset.getXValue(c), dataset.getZValue(c, row));
074        }
075        XYSeriesCollection result = new XYSeriesCollection(series);
076        return result;
077    }
078
079    /**
080     * Returns a dataset containing one series that holds a copy of the (y, z)
081     * data from one column (x-index) of the specified dataset.
082     *
083     * @param dataset  the dataset (<code>null</code> not permitted).
084     * @param column  the column (x) index.
085     * @param seriesName  the series name (<code>null</code> not permitted).
086     *
087     * @return The dataset.
088     */
089    public static XYDataset extractColumnFromHeatMapDataset(
090            HeatMapDataset dataset, int column, Comparable seriesName) {
091        XYSeries series = new XYSeries(seriesName);
092        int rows = dataset.getYSampleCount();
093        for (int r = 0; r < rows; r++) {
094            series.add(dataset.getYValue(r), dataset.getZValue(column, r));
095        }
096        XYSeriesCollection result = new XYSeriesCollection(series);
097        return result;
098    }
099
100    /**
101     * Creates an image that displays the values from the specified dataset.
102     *
103     * @param dataset  the dataset (<code>null</code> not permitted).
104     * @param paintScale  the paint scale for the z-values (<code>null</code>
105     *         not permitted).
106     *
107     * @return A buffered image.
108     */
109    public static BufferedImage createHeatMapImage(HeatMapDataset dataset,
110            PaintScale paintScale) {
111
112        if (dataset == null) {
113            throw new IllegalArgumentException("Null 'dataset' argument.");
114        }
115        if (paintScale == null) {
116            throw new IllegalArgumentException("Null 'paintScale' argument.");
117        }
118        int xCount = dataset.getXSampleCount();
119        int yCount = dataset.getYSampleCount();
120        BufferedImage image = new BufferedImage(xCount, yCount,
121                BufferedImage.TYPE_INT_ARGB);
122        Graphics2D g2 = image.createGraphics();
123        for (int xIndex = 0; xIndex < xCount; xIndex++) {
124            for (int yIndex = 0; yIndex < yCount; yIndex++) {
125                double z = dataset.getZValue(xIndex, yIndex);
126                Paint p = paintScale.getPaint(z);
127                g2.setPaint(p);
128                g2.fillRect(xIndex, yCount - yIndex - 1, 1, 1);
129            }
130        }
131        return image;
132    }
133
134}