ChartDirector Ver 4.1 (ColdFusion Edition)

Pareto Chart




This example demonstrates the pareto chart style.

A pareto chart is a bar chart with the data sorted in descending order, together with a line chart showing the same data in accumulated form. In the current example, the data is shown as both percentages and values on the two y-axes.

The chart in this example is composed of two layers - a BarLayer created using XYChart.addBarLayer, and a LineLayer created using XYChart.addLineLayer.

This example employs the ArrayMath utility class for computing the accumulated line, obtaining the scaling factor between the two y-axes, and re-scaling the line data as percentages.

The two y-axes are synchronized using XYChart.syncYAxis.

Source Code Listing

[File: cfdemo/pareto.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
data = Array(40, 15, 7, 5, 2);

// The labels for the chart
labels = Array("Hard Disk", "PCB", "Printer", "CDROM", "Keyboard");

// Create a XYChart object of size 400 x 225 pixels. Use golden background color,
// with a 2 pixel 3D border.
c = cd.XYChart(400, 225, cd.goldColor(), -1, 2);

// Add a title box using Arial Bold/11 pt font. Set the background color to metallic
// blue (9999FF). Use a 1 pixel 3D border.
c.addTitle("Hardware Defects", "Arial Bold", 11).setBackground(cd.metalColor(
    "0x9999ff"), -1, 1);

// Set the plotarea at (50, 40) and of 300 x 150 pixels in size, with a silver
// background color.
c.setPlotArea(50, 40, 300, 150, cd.silverColor());

// Add a line layer for the pareto line
lineLayer = c.addLineLayer();

// Compute the pareto line by accumulating the data
lineData = cd.ArrayMath(data);
lineData.acc();

// Set a scaling factor such as the maximum point of the line is scaled to 100
scaleFactor = 100 / lineData.max();

// Add the pareto line using the scaled data. Use deep blue (0x80) as the line color,
// with light blue (0x9999ff) diamond symbols
lineLayer.addDataSet(lineData.mul2(scaleFactor).result(), "0x000080").setDataSymbol(
    cd.DiamondSymbol, 9, "0x9999ff");

// Set the line width to 2 pixel
lineLayer.setLineWidth(2);

// Tool tip for the line layer
lineLayer.setHTMLImageMap("", "", "title='Top {={x}+1} items: {value|2}%'");

// Add a multi-color bar layer using the given data.
barLayer = c.addBarLayer3(data);

// Bind the layer to the secondary (right) y-axis.
barLayer.setUseYAxis2();

// Set soft lighting for the bars with light direction from the right
barLayer.setBorderColor(cd.Transparent, cd.softLighting(cd.Right));


// Tool tip for the bar layer
barLayer.setHTMLImageMap("", "", "title='{xLabel}: {value} pieces'");

// Set the labels on the x axis.
c.xAxis().setLabels(labels);

// Set the primary y-axis scale as 0 - 100 with a tick every 20 units
c.yAxis().setLinearScale(0, 100, 20);

// Set the label format of the y-axis label to include a percentage sign
c.yAxis().setLabelFormat("{value}%");

// Add a title to the secondary y-axis
c.yAxis2().setTitle("Frequency");

// Set the secondary y-axis label foramt to show no decimal point
c.yAxis2().setLabelFormat("{value|0}");

// Set the relationship between the two y-axes, which only differ by a scaling factor
c.syncYAxis(1 / scaleFactor);

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

// Include tool tip for the chart
imageMap1 = c.getHTMLImageMap("");

</cfscript>
<html>
<body style="margin:5px 0px 0px 5px">
<div style="font-size:18pt; font-family:verdana; font-weight:bold">
    Pareto 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>