How can PHP libraries like JpGraph or libchart be utilized to create graphical representations of data in PHP?

PHP libraries like JpGraph or libchart can be utilized to create graphical representations of data in PHP by first including the library in your PHP file, then creating an instance of the chart object, setting the data and labels for the chart, and finally outputting the chart to the browser.

// Include the JpGraph library
require_once ('jpgraph/jpgraph.php');
require_once ('jpgraph/jpgraph_bar.php');

// Create a new bar graph instance
$graph = new Graph(400,300);
$graph->SetScale('textlin');

// Create a bar plot
$barplot = new BarPlot(array(23,45,67,89));
$graph->Add($barplot);

// Set the titles and labels
$graph->title->Set("Bar Graph Example");
$graph->xaxis->title->Set("X-axis");
$graph->yaxis->title->Set("Y-axis");

// Display the graph
$graph->Stroke();