Programmatically generating graphs and charts using SVG requires a deep understanding of the SVG specification and the various SVG primitives, as well as a fair amount of time for research, experimentation and debugging. Or, in other words, that's your entire weekend shot! Fortunately, help is at hand. There are a number of open-source PHP libraries that support SVG chart generation, and using them can significantly reduce the amount of work involved in adding this feature to a Web application.

He shows how to create simple images like bar, line and pie charts as well as adding in other things like a legend, custom titles and a sample where the user can define the sizes of a pie chart via some form input fields. Screenshots are included for all code examples to give you a better idea of the end result.

From the article over on ez.no:

Among the additions to the latest eZ Components 2006.2 release is the Graph component, which enables you to create bar, line and pie charts. The output driver mechanism allows you to create different image file types from each chart, and the available renderers make the chart output customizable from simple two-dimensional charts to beautiful three-dimensional data projections.

His introduction covers what the functionality of the component is, what chart types you can make with it (with code examples), and the options for customization it makes possible. He also includes links to a tutorial on its use and the API documentation for you to pick through.