Calculated fields

Is it possible to create calculated fields directly by PHPRad?
I need to develop an inventory manager using weighted average cost… Any suggestions or tutorials that can guide me?

@stefano you can use the ClientEvent in Add/Edit Page Field Properties, which is available in the Radsystems Studio(PHPRad Classic). You are given the option to write your jquery code to calculate fields and add the result to another field in ClientEvents.