Create Excel chart programmatically in PHP

Question

Do you have any idea on how to create a chart in an Excel sheet programmatically from PHP ?

I know you can invoke the Excel COM object, but the server is running on

Answer 1

I think it's not a bad idea to use PHPs GD library like these

WS Charts

Bar graph tutorial

or JpGraph, I'm not sure of the internals but there is free PHP5 and PHP4 versions available