ChartDirector 7.0 (Java Edition)

Scatter Trend Chart




This example demonstrates linear regression trend line fitting together with scatter layers.

The chart in this example has 4 layers - 2 scatter layers created using XYChart.addScatterLayer to show the data points, and two trend layers created using XYChart.addTrendLayer2 for the two trend lines.

Source Code Listing

[JSP Version] jspdemo/scattertrend.jsp
<%@page import="ChartDirector.*, java.util.*" %> <% // The XY data of the first data series double[] dataX0 = {50, 55, 37, 24, 42, 49, 63, 72, 83, 59}; double[] dataY0 = {3.6, 2.8, 2.5, 2.3, 3.8, 3.0, 3.8, 5.0, 6.0, 3.3}; // The XY data of the second data series double[] dataX1 = {50, 55, 37, 24, 42, 49, 63, 72, 83, 59}; double[] dataY1 = {1.6, 1.8, 0.8, 0.5, 1.3, 1.5, 2.3, 2.4, 2.9, 1.5}; // Tool tip formats for data points and trend lines String scatterToolTip = "title='{dataSetName}: Response time at {x} TPS: {value} sec'"; String trendToolTip = "title='Slope = {slope|4} sec/TPS; Intercept = {intercept|4} sec'"; // Create a XYChart object of size 450 x 420 pixels XYChart c = new XYChart(450, 420); // Set the plotarea at (55, 65) and of size 350 x 300 pixels, with white background and a light grey // border (0xc0c0c0). Turn on both horizontal and vertical grid lines with light grey color // (0xc0c0c0) c.setPlotArea(55, 65, 350, 300, 0xffffff, -1, 0xc0c0c0, 0xc0c0c0, -1); // Add a legend box at (50, 30) (top of the chart) with horizontal layout. Use 12pt Times Bold // Italic font. Set the background and border color to Transparent. c.addLegend(50, 30, false, "Times New Roman Bold Italic", 12).setBackground(Chart.Transparent); // Add a title to the chart using 18 point Times Bold Itatic font. c.addTitle("Server Performance", "Times New Roman Bold Italic", 18); // Add titles to the axes using 12pt Arial Bold Italic font c.yAxis().setTitle("Response Time (sec)", "Arial Bold Italic", 12); c.xAxis().setTitle("Server Load (TPS)", "Arial Bold Italic", 12); // Set the axes line width to 3 pixels c.yAxis().setWidth(3); c.xAxis().setWidth(3); // Add a scatter layer using (dataX0, dataY0) ScatterLayer scatter1 = c.addScatterLayer(dataX0, dataY0, "Server AAA", Chart.DiamondSymbol, 11, 0x008000); scatter1.setHTMLImageMap("", "", scatterToolTip); // Add a trend line layer for (dataX0, dataY0) TrendLayer trend1 = c.addTrendLayer2(dataX0, dataY0, 0x008000); trend1.setLineWidth(3); trend1.setHTMLImageMap("", "", trendToolTip); // Add a scatter layer for (dataX1, dataY1) ScatterLayer scatter2 = c.addScatterLayer(dataX1, dataY1, "Server BBB", Chart.TriangleSymbol, 9, 0x6666ff); scatter2.setHTMLImageMap("", "", scatterToolTip); // Add a trend line layer for (dataX1, dataY1) TrendLayer trend2 = c.addTrendLayer2(dataX1, dataY1, 0x6666ff); trend2.setLineWidth(3); trend2.setHTMLImageMap("", "", trendToolTip); // Output the chart WebChartViewer viewer = new WebChartViewer(request, "chart1"); viewer.setChart(c, Chart.SVG); // include tool tip for the chart viewer.setImageMap(c.getHTMLImageMap("")); %> <!DOCTYPE html> <html> <head> <title>Scatter Trend Chart</title> <!-- Include ChartDirector Javascript Library to support chart interactions --> <script type="text/javascript" src="cdjcv.js"></script> </head> <body style="margin:5px 0px 0px 5px"> <div style="font:bold 18pt verdana;"> Scatter Trend Chart </div> <hr style="border:solid 1px #000080; background:#000080" /> <div style="font:10pt verdana; margin-bottom:1.5em"> <a href="viewsource.jsp?file=<%=request.getServletPath()%>">View Source Code</a> </div> <!-- ****** Here is the chart image ****** --> <%= viewer.renderHTML(response) %> </body> </html>