src/org/math/plot/plots/DensityLayerPlot.java

package org.math.plot.plots;

import java.awt.Color;

import javax.swing.JFrame;

import org.math.plot.FrameView;
import org.math.plot.Plot2DPanel;
import org.math.plot.render.AbstractDrawer;
import org.math.plot.utils.Array;

public class DensityLayerPlot extends LayerPlot {

        public static int WIDTH = 2;

        int axis;

        double[] constant_Q;

        double[][] Q;

        public DensityLayerPlot(Plot p, int a, double[] quantiles) {
                this(p, a, new double[0][0]);
                constant_Q = quantiles;
        }

        public DensityLayerPlot(Plot p, int a, double[][] quantiles) {
                super("Density of " + p.name, p);
                if (quantiles != null && quantiles.length > 0)
                        Array.checkRowDimension(quantiles, p.getData().length);
                Q = quantiles;
                axis = a;
        }

        public int getAxe() {
                return axis;
        }

        public void plot(AbstractDrawer draw, Color c) {
                if (!plot.visible)
                        return;

                draw.setColor(c);

                draw.setLineType(AbstractDrawer.CONTINOUS_LINE);
                draw.setLineWidth(WIDTH);
                if (constant_Q == null)
                        for (int i = 0; i < plot.getData().length; i++) {

                                double norm = Double.MAX_VALUE;
                                for (int j = 0; j < Q[i].length - 1; j++)
                                        norm = Math.min(1 / (Q[i][j + 1] - Q[i][j]), norm);

                                double[] d0 = Array.getRowCopy(plot.getData(), i);
                                double[] d1 = Array.getRowCopy(plot.getData(), i);
                                double[] d2 = Array.getRowCopy(plot.getData(), i);

                                for (int j = 0; j < Q[i].length - 2; j++) {
                                        d1[axis] = d0[axis] + ((Q[i][j] + Q[i][j + 1]) / 2);
                                        d2[axis] = d0[axis] + ((Q[i][j + 1] + Q[i][j + 2]) / 2);
                                        Color c1 = new Color(c.getRed(), c.getGreen(), c.getBlue(), (int) (255.0 * (norm / (Q[i][j + 1] - Q[i][j]))));
                                        Color c2 = new Color(c.getRed(), c.getGreen(), c.getBlue(), (int) (255.0 * (norm / (Q[i][j + 2] - Q[i][j + 1]))));
                                        draw.setGradient(d1, c1, d2, c2);
                                        draw.drawLine(d1, d2);
                                }
                        }
                else {

                        double norm = Double.MAX_VALUE;
                        for (int j = 0; j < constant_Q.length - 1; j++)
                                norm = Math.min(1 / (constant_Q[j + 1] - constant_Q[j]), norm);

                        for (int i = 0; i < plot.getData().length; i++) {
                                double[] d0 = Array.getRowCopy(plot.getData(), i);
                                double[] d1 = Array.getRowCopy(plot.getData(), i);
                                double[] d2 = Array.getRowCopy(plot.getData(), i);

                                for (int j = 0; j < constant_Q.length - 2; j++) {
                                        d1[axis] = d0[axis] + (constant_Q[j] + constant_Q[j + 1]) / 2;
                                        d2[axis] = d0[axis] + (constant_Q[j + 1] + constant_Q[j + 2]) / 2;
                                        Color c1 = new Color(c.getRed(), c.getGreen(), c.getBlue(), (int) (255.0 * (norm / (constant_Q[j + 1] - constant_Q[j]))));
                                        Color c2 = new Color(c.getRed(), c.getGreen(), c.getBlue(), (int) (255.0 * (norm / (constant_Q[j + 2] - constant_Q[j + 1]))));
                                        draw.setGradient(d1, c1, d2, c2);
                                        draw.drawLine(d1, d2);
                                }
                        }
                }
                draw.resetGradient();
                draw.setLineWidth(AbstractDrawer.DEFAULT_LINE_WIDTH);

        }

        @Override
        public void setData(double[][] d) {
                //Q = d[0];
        }

        @Override
        public double[][] getData() {
                return null;//new double[][] { sigma };
        }

        public static void main(String[] args) {
                Plot2DPanel p2 = new Plot2DPanel();
                for (int i = 0; i < 2; i++) {
                        double[][] XYZ = new double[10][2];
                        for (int j = 0; j < XYZ.length; j++) {
                                XYZ[j][0] = /*1 + */Math.random();
                                XYZ[j][1] = /*100 * */10 * Math.random();
                        }

                        p2.addScatterPlot("toto" + i, XYZ);
                }
                p2.getPlot(0).addQuantiles(1, new double[] {/*-3,-2,*/-4, -2, -0.5, 0, 0.5, 2, 4 /*,2,3*/});
                p2.getPlot(1).addQuantiles(1, new double[] { -3, -2, -1, 0, 1, 2, 3 });
                //p2.getPlot(1).addLayer(new DensityLayerPlot(p2.getPlot(1), 1, new double[] { -.1, 0, .1 }));

                new FrameView(p2).setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        }
}

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