ChartDirector 7.0 (Java Edition)

Polar Scatter Chart




This example demonstrates how to create polar scatter charts. It also demonstrates using alternating background colors along the angular direction.

A polar scatter chart can be created as a polar line chart with data symbols. The line width is set to 0, so only the symbols can be seen. This will create the effects of a scatter chart.

The detail steps are:

Note that in this example, the polar plot area uses two alternating background colors along the angular direction. This is by using PolarChart.setPlotAreaBg.

Source Code Listing

[JSP Version] jspdemo/polarscatter.jsp
<%@page import="ChartDirector.*, java.util.*" %> <% // The data for the chart double[] data0 = {43, 89, 76, 64, 48, 18, 92, 68, 44, 79, 71, 85}; double[] angles0 = {45, 96, 169, 258, 15, 30, 330, 260, 60, 75, 110, 140}; double[] data1 = {50, 91, 26, 29, 80, 53, 62, 87, 19, 40}; double[] angles1 = {230, 210, 240, 310, 179, 250, 244, 199, 89, 160}; double[] data2 = {88, 65, 76, 49, 80, 53}; double[] angles2 = {340, 310, 340, 210, 30, 300}; // The labels on the angular axis (spokes) String[] labels = {"North", "North\nEast", "East", "South\nEast", "South", "South\nWest", "West", "North\nWest"}; // Create a PolarChart object of size 460 x 460 pixels PolarChart c = new PolarChart(460, 460); // Add a title to the chart at the top left corner using 15pt Arial Bold Italic font c.addTitle2(Chart.TopLeft, "<*underline=2*>Plants in Wonderland", "Arial Bold Italic", 15); // Set center of plot area at (230, 240) with radius 180 pixels c.setPlotArea(230, 240, 180); // Use alternative light grey/dark grey sector background color c.setPlotAreaBg(0xdddddd, 0xeeeeee, false); // Set the grid style to circular grid c.setGridStyle(false); // Add a legend box at the top right corner of the chart using 9pt Arial Bold font c.addLegend(459, 0, true, "Arial Bold", 9).setAlignment(Chart.TopRight); // Set angular axis as 0 - 360, either 8 spokes c.angularAxis().setLinearScale2(0, 360, labels); // Set the radial axis label format c.radialAxis().setLabelFormat("{value} km"); // Add a blue (0xff) polar line layer to the chart using (data0, angle0) PolarLineLayer layer0 = c.addLineLayer(data0, 0x0000ff, "Immortal Weed"); layer0.setAngles(angles0); layer0.setLineWidth(0); layer0.setDataSymbol(Chart.TriangleSymbol, 11); // Add a red (0xff0000) polar line layer to the chart using (data1, angles1) PolarLineLayer layer1 = c.addLineLayer(data1, 0xff0000, "Precious Flower"); layer1.setAngles(angles1); // Disable the line by setting its width to 0, so only the symbols are visible layer1.setLineWidth(0); // Use a 11 pixel diamond data point symbol layer1.setDataSymbol(Chart.DiamondSymbol, 11); // Add a green (0x00ff00) polar line layer to the chart using (data2, angles2) PolarLineLayer layer2 = c.addLineLayer(data2, 0x00ff00, "Magical Tree"); layer2.setAngles(angles2); // Disable the line by setting its width to 0, so only the symbols are visible layer2.setLineWidth(0); // Use a 9 pixel square data point symbol layer2.setDataSymbol(Chart.SquareSymbol, 9); // Output the chart WebChartViewer viewer = new WebChartViewer(request, "chart1"); viewer.setChart(c, Chart.SVG); // Include tool tip for the chart viewer.setImageMap(c.getHTMLImageMap("", "", "title='{dataSetName} at ({value} km, {angle} deg)'")); %> <!DOCTYPE html> <html> <head> <title>Polar Scatter Chart</title> <!-- Include ChartDirector Javascript Library to support chart interactions --> <script type="text/javascript" src="cdjcv.js"></script> </head> <body style="margin:5px 0px 0px 5px"> <div style="font:bold 18pt verdana;"> Polar Scatter Chart </div> <hr style="border:solid 1px #000080; background:#000080" /> <div style="font:10pt verdana; margin-bottom:1.5em"> <a href="viewsource.jsp?file=<%=request.getServletPath()%>">View Source Code</a> </div> <!-- ****** Here is the chart image ****** --> <%= viewer.renderHTML(response) %> </body> </html>