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:

Create a polar line layer using PolarChart.addLineLayer.
Enable data symbols for the line using PolarLayer.setDataSymbol (or PolarLayer.setDataSymbol2 or PolarLayer.setDataSymbol3 or PolarLayer.setDataSymbol4).
Disable the line by setting its width to 0 using PolarLayer.setLineWidth.

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

[File: cfdemo/polarscatter.cfm]

<cfscript>

// ChartDirector for ColdFusion API Access Point
cd = CreateObject("java", "ChartDirector.CFChart");

// A utility to allow us to create arrays with data in one line of code
function Array() {
    var result = ArrayNew(1);
    var i = 0;
    for (i = 1; i LTE ArrayLen(arguments); i = i + 1)
        result[i] = arguments[i];
    return result;
}

// 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<*br*>East", "East", "South<*br*>East", "South", "South<*br*>West",
    "West", "North<*br*>West");

// Create a PolarChart object of size 460 x 460 pixels
c = cd.PolarChart(460, 460);

// Add a title to the chart at the top left corner using 15pt Arial Bold Italic font
c.addTitle2(cd.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(cd.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(cd.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(cd.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(cd.SquareSymbol, 9);

// Output the chart
chart1URL = c.makeSession(GetPageContext(), "chart1");

// Include tool tip for the chart
imageMap1 = c.getHTMLImageMap("", "", "title='{dataSetName} at ({value} km, {angle} deg)'");

</cfscript>
<html>
<body style="margin:5px 0px 0px 5px">
<div style="font-size:18pt; font-family:verdana; font-weight:bold">
    Polar Scatter Chart
</div>
<hr style="border:solid 1px #000080" />
<cfoutput>
<div style="font-size:9pt; font-family:verdana; margin-bottom:1.5em">
    <a href='viewsource.cfm?file=#CGI.SCRIPT_NAME#'>View Source Code</a>
</div>
<img src="getchart.cfm?#chart1URL#" usemap="##map1" border="0" />
<map name="map1">#imageMap1#</map>
</cfoutput>
</body>
</html>