ChartDirector 6.1 (Java 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

[JSP Version] jspdemo/logaxis.jsp
<%@page import="ChartDirector.*" %>
<%@page import="javax.servlet.http.*" %>
<%!
// A simple structure to represent a chart image with an image map
private static class ImageWithHotSpot
{
    String imageURL;
    String imageMap;
}

// Function to create the demo charts
ImageWithHotSpot createChart(HttpServletRequest request, int chartIndex)
{
    // The data for the chart
    double[] data = {100, 125, 260, 147, 67};
    String[] labels = {"Mon", "Tue", "Wed", "Thu", "Fri"};

    // Create a XYChart object of size 200 x 180 pixels
    XYChart c = new 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 == 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
    ImageWithHotSpot ret = new ImageWithHotSpot();
    ret.imageURL = c.makeSession(request, "chart" + chartIndex);

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

    return ret;
}
%>
<%
ImageWithHotSpot chart0 = createChart(request, 0);
ImageWithHotSpot chart1 = createChart(request, 1);
%>
<html>
<body style="margin:5px 0px 0px 5px">
<div style="font-size:18pt; font-family:verdana; font-weight:bold">
    Log Scale Axis
</div>
<hr color="#000080">
<div style="font-size:10pt; font-family:verdana; margin-bottom:1.5em">
    <a href="viewsource.jsp?file=<%=request.getServletPath()%>">View Source Code</a>
</div>
<img src='<%=response.encodeURL("getchart.jsp?"+chart0.imageURL)%>'
    usemap="#map0" border="0">
<map name="map0"><%=chart0.imageMap%></map>
<img src='<%=response.encodeURL("getchart.jsp?"+chart1.imageURL)%>'
    usemap="#map1" border="0">
<map name="map1"><%=chart1.imageMap%></map>
</body>
</html>

[Java Version] javademo/logaxis.java
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import ChartDirector.*;

public class logaxis implements DemoModule
{
    //Name of demo program
    public String toString() { return "Log Scale Axis"; }

    //Number of charts produced in this demo
    public int getNoOfCharts() { return 2; }

    //Main code for creating charts
    public void createChart(ChartViewer viewer, int chartIndex)
    {
        // The data for the chart
        double[] data = {100, 125, 260, 147, 67};
        String[] labels = {"Mon", "Tue", "Wed", "Thu", "Fri"};

        // Create a XYChart object of size 200 x 180 pixels
        XYChart c = new 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 == 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
        viewer.setChart(c);

        //include tool tip for the chart
        viewer.setImageMap(c.getHTMLImageMap("clickable", "",
            "title='Mileage on {xLabel}: {value} miles'"));
    }

    //Allow this module to run as standalone program for easy testing
    public static void main(String[] args)
    {
        //Instantiate an instance of this demo module
        DemoModule demo = new logaxis();

        //Create and set up the main window
        JFrame frame = new JFrame(demo.toString());
        frame.addWindowListener(new WindowAdapter() {
            public void windowClosing(WindowEvent e) {System.exit(0);} });
        frame.getContentPane().setBackground(Color.white);
        frame.getContentPane().setLayout(new FlowLayout(FlowLayout.LEFT));
        frame.setSize(800, 450);

        // Create the charts and put them in the content pane
        for (int i = 0; i < demo.getNoOfCharts(); ++i)
        {
            ChartViewer viewer = new ChartViewer();
            demo.createChart(viewer, i);
            frame.getContentPane().add(viewer);
        }

        // Display the window
        frame.setVisible(true);
    }
}