[Nomad84]

Search for an old post by Vern from before PokerGrapher. He listed the query to use in Access to produce the data used to generate the graphs. You can then copy this into Excel and numerically differentiate there. That would probably be easier than using Matlab, but then again, I've only used Matlab a few times and hated it [img]/images/graemlins/mad.gif[/img] For the projects I do, I much prefer Mathcad. It's much more user friendly, IMO, but I can see how that would depend on your application. FWIW, I would probably try numerically differentiating over a range of quite a few hands rather than trying to get an instantaneous rate, since the instantaneous rate really won't produce any meaningful information (I think). Something like 50-100 hands would probably be a decent number. Something along the lines of:

B51=(A101-A1)/10000

That gets your average BB/100 over a 100 hand range centered at A51. I know that if you use Matlab, you can surely understand what I mean, but I thought a brief description might be useful for some.