ChartDirector Ver 3.1 (PHP Edition Edition)

Dual Y-Axis




This example show demonstrates the dual independent y-axis feature of ChartDirector.

In ChartDirector, any data set can be binded to the primary y-axis or the secondary y-axis, controlled by DataSet.setUseYAxis2. The default is the primary y-axis.

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

Source Code Listing

[File: phpdemo/dualyaxis.php".]
<?php require_once("../lib/phpchartdir.php"); #The data for the chart $data0 = array(0.05, 0.06, 0.48, 0.1, 0.01, 0.05); $data1 = array(100, 125, 265, 147, 67, 105); $labels = array("Jan", "Feb", "Mar", "Apr", "May", "Jun"); #Create a XYChart object of size 300 x 180 pixels $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 8 pts Arial Bold font $c->addTitle("Independent Y-Axis Demo", "arialbd.ttf", 8); #Set the x axis labels using the given labels $c->xAxis->setLabels($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 $yAxis2Obj = $c->yAxis2(); $yAxis2Obj->setTitle("Throughtput (MBytes)"); #set the axis, label and title colors for the primary y axis to green (0x008000) #to match the second data set $yAxis2Obj = $c->yAxis2(); $yAxis2Obj->setColors(0x8000, 0x8000, 0x8000); #Add a line layer to for the first data set using red (0xc00000) color with a #line width to 3 pixels $lineLayerObj = $c->addLineLayer($data0, 0xc00000); $lineLayerObj->setLineWidth(3); #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 $barLayerObj = $c->addBarLayer($data1, 0xc000); $barLayerObj->setUseYAxis2(); #output the chart header("Content-type: image/png"); print($c->makeChart2(PNG)); ?>