ChartDirector 6.1 (Java Edition)

Dual Y-Axis




This example demonstrates a chart with two independent y-axis.

ChartDirector supports arbitrary number of axes. The first two x and y axes are most commonly used and can be retrieved using XYChart.xAxis, XYChart.xAxis2, XYChart.yAxis and XYChart.yAxis2. These axes are by default put at the edges of the plot area.

By default, a data set will bind to the primary y-axis. This can be modified by using DataSet.setUseYAxis or DataSet.setUseYAxis2.

The y-axes in this example are of different colors. This is achieved by using Axis.setColors.

Source Code Listing

[JSP Version] jspdemo/dualyaxis.jsp
<%@page import="ChartDirector.*" %>
<%
// The data for the chart
double[] data0 = {0.05, 0.06, 0.48, 0.1, 0.01, 0.05};
double[] data1 = {100, 125, 265, 147, 67, 105};
String[] labels = {"Jan", "Feb", "Mar", "Apr", "May", "Jun"};

// Create a XYChart object of size 300 x 180 pixels
XYChart c = new XYChart(300, 180);

// Set the plot area at (50, 20) and of size 200 x 130 pixels
c.setPlotArea(50, 20, 200, 130);

// Add a title to the chart using 8pt Arial Bold font
c.addTitle("Independent Y-Axis Demo", "Arial Bold", 8);

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

// Add a title to the primary (left) y axis
c.yAxis().setTitle("Packet Drop Rate (pps)");

// Set the axis, label and title colors for the primary y axis to red (0xc00000) to match the first
// data set
c.yAxis().setColors(0xc00000, 0xc00000, 0xc00000);

// Add a title to the secondary (right) y axis
c.yAxis2().setTitle("Throughtput (MBytes)");

// set the axis, label and title colors for the primary y axis to green (0x008000) to match the
// second data set
c.yAxis2().setColors(0x008000, 0x008000, 0x008000);

// Add a line layer to for the first data set using red (0xc00000) color with a line width to 3
// pixels
LineLayer lineLayer = c.addLineLayer(data0, 0xc00000);
lineLayer.setLineWidth(3);

// tool tip for the line layer
lineLayer.setHTMLImageMap("", "", "title='Packet Drop Rate on {xLabel}: {value} pps'");

// Add a bar layer to for the second data set using green (0x00C000) color. Bind the second data set
// to the secondary (right) y axis
BarLayer barLayer = c.addBarLayer(data1, 0x00c000);
barLayer.setUseYAxis2();

// tool tip for the bar layer
barLayer.setHTMLImageMap("", "", "title='Throughput on {xLabel}: {value} MBytes'");

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

// include tool tip for the chart
String imageMap1 = c.getHTMLImageMap("");
%>
<html>
<body style="margin:5px 0px 0px 5px">
<div style="font-size:18pt; font-family:verdana; font-weight:bold">
    Dual Y-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?"+chart1URL)%>'
    usemap="#map1" border="0">
<map name="map1"><%=imageMap1%></map>
</body>
</html>

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

public class dualyaxis implements DemoModule
{
    //Name of demo program
    public String toString() { return "Dual Y-Axis"; }

    //Number of charts produced in this demo
    public int getNoOfCharts() { return 1; }

    //Main code for creating charts
    public void createChart(ChartViewer viewer, int chartIndex)
    {
        // The data for the chart
        double[] data0 = {0.05, 0.06, 0.48, 0.1, 0.01, 0.05};
        double[] data1 = {100, 125, 265, 147, 67, 105};
        String[] labels = {"Jan", "Feb", "Mar", "Apr", "May", "Jun"};

        // Create a XYChart object of size 300 x 180 pixels
        XYChart c = new XYChart(300, 180);

        // Set the plot area at (50, 20) and of size 200 x 130 pixels
        c.setPlotArea(50, 20, 200, 130);

        // Add a title to the chart using 8pt Arial Bold font
        c.addTitle("Independent Y-Axis Demo", "Arial Bold", 8);

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

        // Add a title to the primary (left) y axis
        c.yAxis().setTitle("Packet Drop Rate (pps)");

        // Set the axis, label and title colors for the primary y axis to red (0xc00000) to match
        // the first data set
        c.yAxis().setColors(0xc00000, 0xc00000, 0xc00000);

        // Add a title to the secondary (right) y axis
        c.yAxis2().setTitle("Throughtput (MBytes)");

        // set the axis, label and title colors for the primary y axis to green (0x008000) to match
        // the second data set
        c.yAxis2().setColors(0x008000, 0x008000, 0x008000);

        // Add a line layer to for the first data set using red (0xc00000) color with a line width
        // to 3 pixels
        LineLayer lineLayer = c.addLineLayer(data0, 0xc00000);
        lineLayer.setLineWidth(3);

        // tool tip for the line layer
        lineLayer.setHTMLImageMap("", "", "title='Packet Drop Rate on {xLabel}: {value} pps'");

        // Add a bar layer to for the second data set using green (0x00C000) color. Bind the second
        // data set to the secondary (right) y axis
        BarLayer barLayer = c.addBarLayer(data1, 0x00c000);
        barLayer.setUseYAxis2();

        // tool tip for the bar layer
        barLayer.setHTMLImageMap("", "", "title='Throughput on {xLabel}: {value} MBytes'");

        // Output the chart
        viewer.setChart(c);

        // include tool tip for the chart
        viewer.setImageMap(c.getHTMLImageMap("clickable"));
    }

    //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 dualyaxis();

        //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);

        // Create the chart and put them in the content pane
        ChartViewer viewer = new ChartViewer();
        demo.createChart(viewer, 0);
        frame.getContentPane().add(viewer);

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