Mikko Koppanen has another post to his blog today that once again shows the combination of PHP and Imagick to create/output an image - this time, it's a simple line graph.
This example demonstrates how Imagick can be used to create graphs. This graphing class itself is mostly a demonstrative example. There are also some hardcoded values in the graph (like the steps in the values on the left hand side) but it should not be hard to refine it into a more elegant graphing solution.
The graph is made using the Imagick drawing functions that extends the standard "draw" class. The code produces a graph with a (straight) line drawn from point to point - code and output examples are both included.