ChartDirector 7.0 (PHP 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

[File: phpdemo/polarscatter.php]
<?php require_once("../lib/phpchartdir.php"); # The data for the chart $data0 = array(43, 89, 76, 64, 48, 18, 92, 68, 44, 79, 71, 85); $angles0 = array(45, 96, 169, 258, 15, 30, 330, 260, 60, 75, 110, 140); $data1 = array(50, 91, 26, 29, 80, 53, 62, 87, 19, 40); $angles1 = array(230, 210, 240, 310, 179, 250, 244, 199, 89, 160); $data2 = array(88, 65, 76, 49, 80, 53); $angles2 = array(340, 310, 340, 210, 30, 300); # The labels on the angular axis (spokes) $labels = array("North", "North\nEast", "East", "South\nEast", "South", "South\nWest", "West", "North\nWest"); # Create a PolarChart object of size 460 x 460 pixels $c = new PolarChart(460, 460); # Add a title to the chart at the top left corner using 15pt Arial Bold Italic font $c->addTitle2(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(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) $layer0 = $c->addLineLayer($data0, 0x0000ff, "Immortal Weed"); $layer0->setAngles($angles0); $layer0->setLineWidth(0); $layer0->setDataSymbol(TriangleSymbol, 11); # Add a red (0xff0000) polar line layer to the chart using (data1, angles1) $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(DiamondSymbol, 11); # Add a green (0x00ff00) polar line layer to the chart using (data2, angles2) $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(SquareSymbol, 9); # Output the chart $viewer = new WebChartViewer("chart1"); $viewer->setChart($c, 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.php?file=<?=basename(__FILE__)?>">View Chart Source Code</a> </div> <!-- ****** Here is the chart image ****** --> <?php echo $viewer->renderHTML(); ?> </body> </html>