ChartDirector 6.0 (ColdFusion Edition)

Log Scale Axis


  

This example demonstrates using a log scale axis versus a linear scale axis.

In ChartDirector, log scale axis can be configured using Axis.setLogScale, Axis.setLogScale2 or Axis.setLogScale3.

Source Code Listing

[File: cfdemo/logaxis.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;
}

// Function to create the demo charts
function createChart(chartIndex)
{
    // Declare local variables
    var data = 0;
    var labels = 0;
    var c = 0;
    var ret = 0;

    // The data for the chart
    data = Array(100, 125, 260, 147, 67);
    labels = Array("Mon", "Tue", "Wed", "Thu", "Fri");

    // Create a XYChart object of size 200 x 180 pixels
    c = cd.XYChart(200, 180);

    // Set the plot area at (30, 10) and of size 140 x 130 pixels
    c.setPlotArea(30, 10, 140, 130);

    // Ise log scale axis if required
    if (chartIndex EQ 1) {
        c.yAxis().setLogScale3();
    }

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

    // Add a color bar layer using the given data. Use a 1 pixel 3D border for the bars.
    c.addBarLayer3(data).setBorderColor(-1, 1);

    // Output the chart
    ret = StructNew();
    ret.imageURL = c.makeSession(GetPageContext(), "chart" & chartIndex);

    // Include tool tip for the chart
    ret.imageMap = c.getHTMLImageMap("", "", "title='Mileage on {xLabel}: {value} miles'");

    return ret;
}

chart0 = createChart(0);
chart1 = createChart(1);

</cfscript>
<html>
<body style="margin:5px 0px 0px 5px">
<div style="font-size:18pt; font-family:verdana; font-weight:bold">
    Log Scale Axis
</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?#chart0.imageURL#" usemap="##map0" border="0" />
<map name="map0">#chart0.imageMap#</map>
<img src="getchart.cfm?#chart1.imageURL#" usemap="##map1" border="0" />
<map name="map1">#chart1.imageMap#</map>
</cfoutput>
</body>
</html>