This is a bar chart with three data sets plotted. The data type is 'text-data', so the X values are implicit. But the X values are not relevant because the data labels (month names) are used instead, and the X tick marks and labels are turned off. This plot uses the default shading of bars.
Example 5.4. Bar Chart
<?php
# PHPlot Example: Bar chart, 3 data sets, shaded
require_once 'phplot.php';
$data = array(
array('Jan', 40, 2, 4), array('Feb', 30, 3, 4), array('Mar', 20, 4, 4),
array('Apr', 10, 5, 4), array('May', 3, 6, 4), array('Jun', 7, 7, 4),
array('Jul', 10, 8, 4), array('Aug', 15, 9, 4), array('Sep', 20, 5, 4),
array('Oct', 18, 4, 4), array('Nov', 16, 7, 4), array('Dec', 14, 3, 4),
);
$plot = new PHPlot(800, 600);
$plot->SetImageBorderType('plain');
$plot->SetPlotType('bars');
$plot->SetDataType('text-data');
$plot->SetDataValues($data);
# Main plot title:
$plot->SetTitle('Shaded Bar Chart with 3 Data Sets');
# Make a legend for the 3 data sets plotted:
$plot->SetLegend(array('Engineering', 'Manufacturing', 'Administration'));
# Turn off X tick labels and ticks because they don't apply here:
$plot->SetXTickLabelPos('none');
$plot->SetXTickPos('none');
$plot->DrawGraph();