This example demonstrates swapping the x and y axes to produce an rotated area chart in which the area goes from left to right (instead of bottom to top).

The x and y axes in the example are configured as follows:

• Initially, the direction of the x-axis is left to right and is at the bottom of the chart, while the y-axis is from bottom to top and is on the left of the chart.
  
  
• Swap the x and y axes using XYChart.swapXY. Now the x-axis is from bottom to top and is on the left of the chart, while the y-axis is from left to right and is at the bottom of the chart.
  
  
• Use XYChart.setYAxisOnRight to move the y-axis to the opposite side of the plot area, so that the y-axis is on the top of the plot area (instead of at the bottom). (Note: setYAxisOnRight moves the primary y-axis to the opposite side. It is the right side by default, but will become the top side if x and y axes are swapped. The name of this method is for compatibility with earlier versions of ChartDirector in which XYChart.swapXY was not supported.)
  
  
• Use Axis.setReverse to reverse the direction of the x-axis, so that the x-axis is from top to bottom (instead of bottom to top).

The area in this chart is filled using a gradient color created with BaseChart.gradientColor.

[File: phpdemo/rotatedarea.php".]

<?php require_once("../lib/phpchartdir.php"); #The data for the area chart $data = array(30, 28, 40, 55, 75, 68, 54, 60, 50, 62, 75, 65, 75, 89, 60, 55, 53, 35, 50, 66, 56, 48, 52, 65, 62); #The labels for the area chart $labels = array("0 m", "", "", "3 m", "", "", "6 m", "", "", "9 m", "", "", "12 m", "", "", "15 m", "", "", "18 m", "", "", "21 m", "", "", "24 m"); #Create a XYChart object of size 320 x 320 pixels $c = new XYChart(320, 320); #Swap the x and y axis to become a rotated chart $c->swapXY(); #Set the y axis on the top side (right + rotated = top) $c->setYAxisOnRight(); #Reverse the x axis so it is pointing downwards $c->xAxis->setReverse(); #Set the plotarea at (50, 50) and of size 200 x 200 pixels. Enable horizontal #and vertical grids by setting their colors to grey (0xc0c0c0). $plotAreaObj = $c->setPlotArea(50, 50, 250, 250); $plotAreaObj->setGridColor(0xc0c0c0, 0xc0c0c0); #Add a line chart layer using the given data $c->addAreaLayer($data, $c->gradientColor(50, 0, 300, 0, 0xffffff, 0xff)); #Set the x axis labels using the given labels $c->xAxis->setLabels($labels); #Add a title to the x axis $c->xAxis->setTitle("Depth"); #Add a title to the y axis $c->yAxis->setTitle("Carbon Dioxide Concentration (ppm)"); #output the chart header("Content-type: image/png"); print($c->makeChart2(PNG)); ?>