I am trying to obtain the equivalent of a matlab Pcolor added on a polar() function but in java.
I am pretty new to the language, but managed to obtain a polar plot already, with the following code:
public class Polar extends JFrame {
public Polar(double[][] vec){
XYDataset dataset = getXYDataset(vec);
JFreeChart chart = ChartFactory.createPolarChart("test", dataset, true, true, true);
PolarPlot plot = (PolarPlot) chart.getPlot();
DefaultPolarItemRenderer render = (DefaultPolarItemRenderer)
plot.getRenderer();
render.setFillComposite(...);
render.setSeriesFilled(0,true);
ChartPanel panel = new ChartPanel(chart);
panel.setMouseZoomable(false);
setContentPane(panel);
}
private XYDataset getXYDataset(double[][] vec){
XYSeriesCollection dataset = new XYSeriesCollection();
XYSeries faultDP =new XYSeries("Serie1");
for(int i = 0; i<vec.length; i++){
faultDP.add(vec[i][1],vec[i][0]);
}
dataset.addSeries(faultDP);
return dataset;
}
}
The array vec contains the speed and angle of my variable, and should be plotted on the polar plot. this works fine.
The next step would be to pass a new variable, a double[][] vector of dimension 90x360. Each cell should be plotted on the polar plot with background color value, a bit like in the picture below.
Any idea on how to do so ?
Cheers,
Flo
So, I've looked into what trashgod offered me and came with this code:
public class PolarTest extends JFrame {
public PolarTest(double[][] dipaz, double[][] val){
JFrame f = new JFrame("Title");
ChartPanel panel = new ChartPanel(createChart(val, dipaz));
panel.setPreferredSize(new Dimension(500,500));
f.add(panel);
f.pack();
f.setLocationRelativeTo(null);
f.setVisible(true);
}
private JFreeChart createChart(double[][] val,double[][] dipaz){
XYSeriesCollection dataset = new XYSeriesCollection ();
double step, min, max;
min = val[0][2];
max = val[val.length-1][2];
step = (max-min)/10; //creation of 10 areas of similar heat range
dataset = (XYSeriesCollection) createDataset(val,step);
JFreeChart chart = ChartFactory.createPolarChart("test", dataset, true, true, true);
PolarPlot plot = (PolarPlot) chart.getPlot();
DefaultPolarItemRenderer r = (DefaultPolarItemRenderer) plot.getRenderer();
r.setFillComposite(AlphaComposite.getInstance(AlphaComposite.SRC_OVER,0.5f));
for(int i =0; i<dataset.getSeriesCount(); i++){
r.setSeriesFilled(i, true);
r.setShapesVisible(false);
r.setDrawOutlineWhenFilled(false);
}
NumberAxis rangeAxis = (NumberAxis) plot.getAxis();
rangeAxis.setTickLabelsVisible(false);
return chart;
}
private XYDataset createDataset(double[][] val, double step){
XYSeriesCollection result = new XYSeriesCollection();
double dpTmp, breakPoint;
int cpt=1;
boolean t;
t= true;
dpTmp = val[0][2];
breakPoint = dpTmp + step;
XYSeries series = null ;
for(int i = 0; i< val.length; i++){
if(val[i][2] < breakPoint){
if(t){
series = new XYSeries(String.valueOf(cpt));
t = false;
}
series.add(val[i][1],val[i][0]);
cpt++;
}else{
result.addSeries(series);
i--;
t=true;
breakPoint = val[i][2] + step;
}
}
return result;
}
The array dipaz contains my angle and dip (of X,Y dots I'd like to later plot on the polar representation), while val a 3 by N array:
val[][0] = dip
val[][1] = angle
val[][2] = value of "heat" , if we see that problem as a heatmap.
val is ascending sorted by the third column. My idea was to split the whole array in 10 (or more) areas of similar heat values.
if I run this code, I obtain the following output (cf pic). We can see that it's getting there, but not quite. I am not sure that this code is able to map correctly my heat on the polar plot>
How could I get closer to the picture I posted in my first post?
Thank you for your help.
Flo
Related
This question already has answers here:
Logarithmic Axis Labels/Ticks Customization
(3 answers)
Closed 6 years ago.
I am using JFree to generate my chart. Below is the image for your reference. As visible in image current scale is based on 10 so 10,100,1000 are there in x-axis scale. Would it possible to change it to log 2. So in case of log 2 point would be visible 2,4,8,16,32, 64 and so on. Class LogarithmicAxis.java is being used for rendering x-axis.
Please let me know if its possible
Below code generate log 2 scale but I am not able to set x-axis point vertically which is very important for me.
public class TestHello {
/** #see http://stackoverflow.com/a/10353270/230513 */
private static void createFrame() {
int N=22;
XYSeries series = new XYSeries("Series");
for (int i = 0; i <= N; i++) {
System.out.println(Math.pow(2, i));
Random r = new Random();
double randomInt = r.nextInt(100) + 1;
series.add(Math.pow(2, i),randomInt);
}
NumberAxis yAxis = new NumberAxis("Y");
yAxis.setStandardTickUnits(NumberAxis.createIntegerTickUnits());
LogAxis xAxis = new LogAxis("X");
xAxis.setBase(2);
xAxis.setStandardTickUnits(NumberAxis.createIntegerTickUnits());
xAxis.setVerticalTickLabels(true);
JFreeChart chart = ChartFactory.createXYLineChart(
"Text", "x", "y", new XYSeriesCollection(series),
PlotOrientation.VERTICAL, true, true, false);
final XYPlot plot = chart.getXYPlot();
plot.setBackgroundPaint(Color.WHITE);
plot.setDomainAxis(xAxis);
plot.setRangeAxis(yAxis);
final Marker start = new ValueMarker(60.0);
XYLineAndShapeRenderer renderer = new XYLineAndShapeRenderer();
renderer.setLegendLine(new Line2D.Double(-20.0D, 0.0D, 20.0D, 0.0D));
Shape square = new Rectangle2D.Double(-2.0, -2.0, 3.0, 3.0);
renderer.setSeriesShape(0, square);
plot.setRenderer(renderer);
plot.addRangeMarker(start);
JFrame frame = new JFrame("LogAxis Test");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setContentPane(new ChartPanel(chart));
frame.pack();
frame.setVisible(true);
}
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
#Override
public void run() {
createFrame();
}
});
}
}
Try using the LogAxis class rather than the LogarithmicAxis class (there are two, for historical reasons) and call axis.setBase(2.0) when you set up the axis.
I am calculating histogram of red component of the image and stored it in redhisto[]. The index of the array represent the intensity(0 to 255)
and the value represent the number of pixel with that intensity. Then plotting those values with JFreeChart.
My question is:
How to make X-axis value start from 0. Now its starting from negative number.
Can we change the color of the bars in the graph
code is :
public class Histogram extends ApplicationFrame {
public Histogram(final String title) throws IOException {
super(title);
IntervalXYDataset dataset = createDataset();
JFreeChart chart = createChart(dataset);
final ChartPanel chartPanel = new ChartPanel(chart);
chartPanel.setPreferredSize(new java.awt.Dimension(500, 270));
setContentPane(chartPanel);
}
private IntervalXYDataset createDataset() throws IOException {
BufferedImage imageA = ImageIO.read(new File("XYZ.bmp"));
int[] red = new int[imageA.getHeight()*imageA.getWidth()];
int[] redhisto = new int[256];
int[] pixel;
int k= 0;
for (int y = 0; y < imageA.getHeight(); y++) {
for (int x = 0; x < imageA.getWidth(); x++) {
pixel = imageA.getRaster().getPixel(x, y, new int[3]);
red[k] = pixel[0];
k++;
}
}
for(int x=0;x<red.length;x++){
int y = red[x];
redhisto[y]++;
}
final XYSeries series = new XYSeries("No of pixels");
for(int i=0; i<redhisto.length;i++)
series.add(i,redhisto[i]);
final XYSeriesCollection dataset = new XYSeriesCollection(series);
return dataset;
}
private JFreeChart createChart(IntervalXYDataset dataset) {
final JFreeChart chart = ChartFactory.createXYBarChart("Color Intensity Histogram","X",false,"Y",dataset,PlotOrientation.VERTICAL,true,true,false);
XYPlot plot = (XYPlot) chart.getPlot();
return chart;
}
public static void main(final String[] args) throws IOException {
final Histogram demo = new Histogram("Image Histogram");
demo.pack();
RefineryUtilities.centerFrameOnScreen(demo);
demo.setVisible(true);
}
}
You can change the lower bound of the domain axis and set the series paint as shown below. The default XYBarPainter has a gradient color highlight, so I used a StandardXYBarPainter.
XYPlot plot = (XYPlot) chart.getPlot();
ValueAxis axis = plot.getDomainAxis();
axis.setLowerBound(0);
XYBarRenderer r = (XYBarRenderer) plot.getRenderer();
r.setBarPainter(new StandardXYBarPainter());
r.setSeriesPaint(0, Color.blue);
XYPlot plot = (XYPlot) chart.getPlot();
//To change the lower bound of X-axis
NumberAxis xAxis = (NumberAxis) plot.getDomainAxis();
xAxis.setLowerBound(0);
//To change the lower bound of Y-axis
NumberAxis yAxis = (NumberAxis) plot.getRangeAxis();
yAxis.setLowerBound(0);
// To change the color
XYItemRenderer renderer = plot.getRenderer();
renderer.setSeriesPaint(0, Color.green);
I have two data series with two different Y-axis and a single X-axis. I am trying to plot a Dual Y-Axis (or in Excel known as Secondary Y-Axis) so that the chart are scaled. But I only get a single Y-axis for both data series. Note: I am using AChartEngine 1.1.0
Can anyone please advise.
My code is given below with a screenshot.
public class LineChart {
public Intent getIntent(Context context){
int[] x = {1,2,3,4,5,6,7,8,9,10};
int[] y = {22,45,34,45,55,65,74,85,93,100};
TimeSeries series = new TimeSeries("Data1");
for(int i = 0; i<x.length; i++){
series.add(x[i], y[i]);
}
int[] x2 = {1,2,3,4,5,6,7,8,9,10};
int[] y2 = {223,454,334,454,554,655,745,855,935,510};
TimeSeries series2 = new TimeSeries("Data2");
for(int i = 0; i<x.length; i++){
series2.add(x2[i], y2[i]);
}
//Multiple Series Data Set
XYMultipleSeriesDataset dataset = new XYMultipleSeriesDataset();
dataset.addSeries(series); //First Data Series
dataset.addSeries(series2); //Second Data Series
//Multiple Series Renderer
XYMultipleSeriesRenderer mRenderer = new XYMultipleSeriesRenderer(2);
//Background
mRenderer.setApplyBackgroundColor(true);
mRenderer.setBackgroundColor(Color.BLACK);
//mRenderer.setMarginsColor(Color.parseColor("#F5F5F5"));
//Grid
mRenderer.setShowGridY(true);
mRenderer.setShowGridX(true);
mRenderer.setGridColor(Color.WHITE);
//Label
mRenderer.setLabelsTextSize(14);
mRenderer.setXLabelsColor(Color.GREEN);
//Min and Max
mRenderer.setXAxisMax(series.getMaxX());
mRenderer.setXAxisMin(series.getMinX());
//Dual yaxis
mRenderer.setYLabelsColor(0, Color.GREEN);
mRenderer.setYLabelsColor(1, Color.RED);
mRenderer.setYTitle("Y-AXIS1", 0);
mRenderer.setYTitle("Y-AXIS2", 1);
mRenderer.setYAxisAlign(Align.LEFT, 0);
mRenderer.setYAxisAlign(Align.RIGHT, 1);
mRenderer.setYLabelsAlign(Align.LEFT, 0);
mRenderer.setYLabelsAlign(Align.RIGHT, 1);
//First Series - Single Series Renderer
XYSeriesRenderer renderer = new XYSeriesRenderer();
renderer.setColor(Color.RED);
renderer.setPointStyle(PointStyle.CIRCLE);
renderer.setFillPoints(true);
//Second Series - Single Series Renderer
XYSeriesRenderer renderer2 = new XYSeriesRenderer();
renderer2.setColor(Color.GREEN);
renderer2.setPointStyle(PointStyle.CIRCLE);
renderer2.setFillPoints(true);
//Add renderers to multiple series Renderer
mRenderer.addSeriesRenderer(renderer);
mRenderer.addSeriesRenderer(renderer2);
Intent intent = ChartFactory.getLineChartIntent(context, dataset, mRenderer, "Line Graph Title");
return intent;
}
}
Finally, I have done it using this example - here
I have a dataset of points (x,y) and I would like to create an heatmap of this dataset. More specifically, I would like an image in which I have lighter colors in the areas where I have a bigger concentration of points and darker where there are less points.
I am using JFreeChart libraries and I found some classes for example DefaultHeatMapDataset but I am not sure how to use them in the proper way.
Does anybody has a clue on how to do it?
Thanks in advance!
Giovanni
Use an XYBlockRenderer with a suitable implementation of XYZDataset and a corresponding implementation of PaintScale.
Creating a heatmap in JFreeChart is a bit tricky, as there is still (as of version 1.0.19/1.5.0) no chart-type resp. plot for this usecase. (The available HeatMapDataset was written to be used with HeatMapUtilities as David Gilbert wrote in the forum.)
So best way for creating a heatmap is using an XYPlot with an XYBlockRenderer and an XYZDataset, as trashgod already wrote.
Here is a complete, minimalistic example that you can run to get the chart shown below:
import org.jfree.chart.ChartPanel;
import org.jfree.chart.JFreeChart;
import org.jfree.chart.axis.*;
import org.jfree.chart.plot.XYPlot;
import org.jfree.chart.renderer.LookupPaintScale;
import org.jfree.chart.renderer.xy.XYBlockRenderer;
import org.jfree.chart.title.PaintScaleLegend;
import org.jfree.data.xy.DefaultXYZDataset;
import org.jfree.data.xy.XYZDataset;
import org.jfree.ui.ApplicationFrame;
import org.jfree.ui.RectangleEdge;
import java.awt.*;
import java.util.Random;
public class HeatMapDemo extends ApplicationFrame
{
public HeatMapDemo()
{
super("JFreeChart Heatmap Demo");
final JFreeChart chart = createChart(createDataset());
setContentPane(new ChartPanel(chart));
}
private static JFreeChart createChart(XYZDataset dataset)
{
// x-axis for time
DateAxis xAxis = new DateAxis("Time");
xAxis.setStandardTickUnits(DateAxis.createStandardDateTickUnits());
xAxis.setLowerMargin(0);
xAxis.setUpperMargin(0);
// visible y-axis with symbols
String labels[] = new String[500];
for (int i = 0; i < 500; i++)
labels[i] = "ca. " + i + "nm";
SymbolAxis yAxis = new SymbolAxis(null, labels);
yAxis.setTickUnit(new NumberTickUnit(50));
// another invisible y-axis for scaling
// (this is not necessary if your y-values are suitable)
NumberAxis valueAxis1 = new NumberAxis("Marker");
valueAxis1.setLowerMargin(0);
valueAxis1.setUpperMargin(0);
valueAxis1.setVisible(false);
// create a paint-scale and a legend showing it
LookupPaintScale paintScale = new LookupPaintScale(0, 300, Color.black);
Color c = Color.green;
paintScale.add(0.0, c);
paintScale.add(33.0, c = c.darker());
paintScale.add(66.0, c.darker());
paintScale.add(100.0, c = Color.blue);
paintScale.add(133.0, c = c.darker());
paintScale.add(166.0, c.darker());
paintScale.add(200.0, c = Color.red.darker().darker());
paintScale.add(233.0, c = c.brighter());
paintScale.add(266.0, c.brighter());
PaintScaleLegend psl = new PaintScaleLegend(paintScale, new NumberAxis());
psl.setPosition(RectangleEdge.RIGHT);
psl.setAxisLocation(AxisLocation.TOP_OR_RIGHT);
psl.setMargin(50.0, 20.0, 80.0, 0.0);
// finally a renderer and a plot
XYPlot plot = new XYPlot(dataset, xAxis, yAxis, new XYBlockRenderer());
((XYBlockRenderer)plot.getRenderer()).setPaintScale(paintScale);
// 2 optional lines, depending on your y-values
plot.setRangeAxis(1, valueAxis1);
plot.mapDatasetToRangeAxis(0, 1);
JFreeChart chart = new JFreeChart(null, null, plot, false);
chart.addSubtitle(psl);
return chart;
}
public XYZDataset createDataset()
{
double[] xvalues = new double[1000*100]; // date
double[] yvalues = new double[1000*100]; // numeric (1-100)
double[] zvalues = new double[1000*100]; // numeric (the actual data)
// create some random data
final Random rand = new Random();
long l = System.currentTimeMillis();
for (int i = 0; i < 1000; i++) {
l -= 600000;
for (int j = 0; j < 100; j++) {
final int idx = i * 100 + j;
xvalues[idx] = l;
yvalues[idx] = j;
double delta = rand.nextInt(15) * (rand.nextInt(4) == 0 ? -1 : 1);
zvalues[idx] = Math.max(0, Math.min(300,
(idx < 1000 ? 0 : zvalues[idx - 1000]) + delta));
}
}
DefaultXYZDataset dataset = new DefaultXYZDataset();
dataset.addSeries("Just one Series", new double[][] { xvalues, yvalues, zvalues });
return dataset;
}
public static void main(String args[])
{
final HeatMapDemo demo = new HeatMapDemo();
demo.pack();
demo.setVisible(true);
}
}
The produced heatmap looks like this:
If you need a more linear PaintScale, you could have a look a the SpectrumPaintScale implementation in this answer.
This is my First Month with Java, so I apologize for my stupid question in advance. I'm trying to make a simple program using Jfreechart. I want to display my 2D array on the scatter plot.
here is the code:
package myappthatusesjfreechart;
import org.jfree.chart.ChartFactory;
import org.jfree.chart.ChartFrame;
import org.jfree.chart.JFreeChart;
import org.jfree.chart.plot.PlotOrientation;
import org.jfree.data.general.DefaultPieDataset;
public class MyAppThatUsesJFreeChart {
public static void main(String[] args) {
// create a dataset...
int[][] a2 = new int[10][5];
// print array in rectangular form
for (int r = 0; r < a2.length; r++) {
for (int c = 0; c < a2[r].length; c++) {
System.out.print(" " + a2[r][c]);
}
System.out.println("");
}
// create a chart...
JFreeChart chart = ChartFactory.createScatterPlot(
"Scatter Plot", // chart title
"X", // x axis label
"Y", // y axis label
a2, // data ***-----PROBLEM------***
PlotOrientation.VERTICAL,
true, // include legend
true, // tooltips
false // urls
);
// create and display a frame...
ChartFrame frame = new ChartFrame("First", chart);
frame.pack();
frame.setVisible(true);
}
}
The ;ChartFactory.createScatterPlot; is not allowing me to pass the 2d array, I want to ask is there any way that i can do it.
The createScatterPlot() method expects an XYDataset, such as XYSeriesCollection. There are examples using XYSeriesCollection here and here.
Addendum: Here's an example more suited to a scatter plot; just replace a2 with createDataset() in the factory call.
private static final Random r = new Random();
private static XYDataset createDataset() {
XYSeriesCollection result = new XYSeriesCollection();
XYSeries series = new XYSeries("Random");
for (int i = 0; i <= 100; i++) {
double x = r.nextDouble();
double y = r.nextDouble();
series.add(x, y);
}
result.addSeries(series);
return result;
}