ChartDirector 7.0 (ASP/COM/VB 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

[Web Version (in ASP)] aspdemo\scattertrend.asp
<%@ language="vbscript" %> <% Set cd = CreateObject("ChartDirector.API") ' The XY data of the first data series dataX0 = Array(50, 55, 37, 24, 42, 49, 63, 72, 83, 59) dataY0 = Array(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 dataX1 = Array(50, 55, 37, 24, 42, 49, 63, 72, 83, 59) dataY1 = Array(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 scatterToolTip = "title='{dataSetName}: Response time at {x} TPS: {value} sec'" trendToolTip = "title='Slope = {slope|4} sec/TPS; Intercept = {intercept|4} sec'" ' Create a XYChart object of size 450 x 420 pixels Set c = cd.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) Call c.setPlotArea(55, 65, 350, 300, &Hffffff, -1, &Hc0c0c0, &Hc0c0c0, -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. Call c.addLegend(50, 30, False, "Times New Roman Bold Italic", 12).setBackground(cd.Transparent) ' Add a title to the chart using 18 point Times Bold Itatic font. Call c.addTitle("Server Performance", "Times New Roman Bold Italic", 18) ' Add titles to the axes using 12pt Arial Bold Italic font Call c.yAxis().setTitle("Response Time (sec)", "Arial Bold Italic", 12) Call c.xAxis().setTitle("Server Load (TPS)", "Arial Bold Italic", 12) ' Set the axes line width to 3 pixels Call c.yAxis().setWidth(3) Call c.xAxis().setWidth(3) ' Add a scatter layer using (dataX0, dataY0) Set scatter1 = c.addScatterLayer(dataX0, dataY0, "Server AAA", cd.DiamondSymbol, 11, &H008000) Call scatter1.setHTMLImageMap("", "", scatterToolTip) ' Add a trend line layer for (dataX0, dataY0) Set trend1 = c.addTrendLayer2(dataX0, dataY0, &H008000) Call trend1.setLineWidth(3) Call trend1.setHTMLImageMap("", "", trendToolTip) ' Add a scatter layer for (dataX1, dataY1) Set scatter2 = c.addScatterLayer(dataX1, dataY1, "Server BBB", cd.TriangleSymbol, 9, &H6666ff) Call scatter2.setHTMLImageMap("", "", scatterToolTip) ' Add a trend line layer for (dataX1, dataY1) Set trend2 = c.addTrendLayer2(dataX1, dataY1, &H6666ff) Call trend2.setLineWidth(3) Call trend2.setHTMLImageMap("", "", trendToolTip) ' Output the chart Set viewer = cd.WebChartViewer(Request, "chart1") Call viewer.setChart(c, cd.SVG) ' include tool tip for the chart viewer.ImageMap = 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.asp?file=<%= Request("SCRIPT_NAME") %>">View Chart Source Code</a> </div> <!-- ****** Here is the chart image ****** --> <%= viewer.renderHTML() %> </body> </html>

[Windows Version (in Visual Basic)] vbdemo\scattertrend.cls
Public Sub createChart(viewer As Object, chartIndex As Integer) Dim cd As New ChartDirector.API ' The XY data of the first data series Dim dataX0() dataX0 = Array(50, 55, 37, 24, 42, 49, 63, 72, 83, 59) Dim dataY0() dataY0 = Array(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 Dim dataX1() dataX1 = Array(50, 55, 37, 24, 42, 49, 63, 72, 83, 59) Dim dataY1() dataY1 = Array(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 Dim scatterToolTip As String scatterToolTip = "title='{dataSetName}: Response time at {x} TPS: {value} sec'" Dim trendToolTip As String trendToolTip = "title='Slope = {slope|4} sec/TPS; Intercept = {intercept|4} sec'" ' Create a XYChart object of size 450 x 420 pixels Dim c As XYChart Set c = cd.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) Call c.setPlotArea(55, 65, 350, 300, &Hffffff, -1, &Hc0c0c0, &Hc0c0c0, -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. Call c.addLegend(50, 30, False, "timesbi.ttf", 12).setBackground(cd.Transparent) ' Add a title to the chart using 18 point Times Bold Itatic font. Call c.addTitle("Server Performance", "timesbi.ttf", 18) ' Add titles to the axes using 12pt Arial Bold Italic font Call c.yAxis().setTitle("Response Time (sec)", "arialbi.ttf", 12) Call c.xAxis().setTitle("Server Load (TPS)", "arialbi.ttf", 12) ' Set the axes line width to 3 pixels Call c.yAxis().setWidth(3) Call c.xAxis().setWidth(3) ' Add a scatter layer using (dataX0, dataY0) Dim scatter1 As ScatterLayer Set scatter1 = c.addScatterLayer(dataX0, dataY0, "Server AAA", cd.DiamondSymbol, 11, &H008000) Call scatter1.setHTMLImageMap("", "", scatterToolTip) ' Add a trend line layer for (dataX0, dataY0) Dim trend1 As TrendLayer Set trend1 = c.addTrendLayer2(dataX0, dataY0, &H008000) Call trend1.setLineWidth(3) Call trend1.setHTMLImageMap("", "", trendToolTip) ' Add a scatter layer for (dataX1, dataY1) Dim scatter2 As ScatterLayer Set scatter2 = c.addScatterLayer(dataX1, dataY1, "Server BBB", cd.TriangleSymbol, 9, &H6666ff) Call scatter2.setHTMLImageMap("", "", scatterToolTip) ' Add a trend line layer for (dataX1, dataY1) Dim trend2 As TrendLayer Set trend2 = c.addTrendLayer2(dataX1, dataY1, &H6666ff) Call trend2.setLineWidth(3) Call trend2.setHTMLImageMap("", "", trendToolTip) ' Output the chart Set viewer.Picture = c.makePicture() ' include tool tip for the chart viewer.ImageMap = c.getHTMLImageMap("clickable") End Sub