ChartDirector 7.0 (Java Edition)

Polar Vector Chart




This example demonstrates a polar vector chart.

A vector chart is like a scatter chart, but the symbols are arrows which can be of arbitrary lengths pointing to arbitrary directions. Thus each symbol in a vector chart is specified by 4 values - the radial and angular coordinates, and the length and the direction.

In ChartDirector, a polar vector layer is created using PolarChart.addVectorLayer.

Source Code Listing

[JSP Version] jspdemo/polarvector.jsp
<%@page import="ChartDirector.*, java.util.*" %> <% // Coordinates of the starting points of the vectors double[] radius = {5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25}; double[] angle = {0, 30, 60, 90, 120, 150, 180, 210, 240, 270, 300, 330, 0, 30, 60, 90, 120, 150, 180, 210, 240, 270, 300, 330, 0, 30, 60, 90, 120, 150, 180, 210, 240, 270, 300, 330, 0, 30, 60, 90, 120, 150, 180, 210, 240, 270, 300, 330, 0, 30, 60, 90, 120, 150, 180, 210, 240, 270, 300, 330}; // Magnitude and direction of the vectors double[] magnitude = {5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1}; double[] direction = {60, 90, 120, 150, 180, 210, 240, 270, 300, 330, 0, 30, 60, 90, 120, 150, 180, 210, 240, 270, 300, 330, 0, 30, 60, 90, 120, 150, 180, 210, 240, 270, 300, 330, 0, 30, 60, 90, 120, 150, 180, 210, 240, 270, 300, 330, 0, 30, 60, 90, 120, 150, 180, 210, 240, 270, 300, 330, 0, 30}; // 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.addTitle("Polar Vector Chart Demonstration", "Arial Bold Italic", 15); // Set center of plot area at (230, 240) with radius 180 pixels c.setPlotArea(230, 240, 180); // Set the grid style to circular grid c.setGridStyle(false); // Set angular axis as 0 - 360, with a spoke every 30 units c.angularAxis().setLinearScale(0, 360, 30); // Add a polar vector layer to the chart with blue (0000ff) vectors c.addVectorLayer(radius, angle, magnitude, direction, Chart.RadialAxisScale, 0x0000ff); // 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='Vector at ({value}, {angle} deg): Length = {len}, Angle = {dir} deg'")); %> <!DOCTYPE html> <html> <head> <title>Polar Vector 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 Vector 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>