From: <HIDDEN>
Newsgroups: comp.soft-sys.matlab
Subject: differentiation
Date: Wed, 12 May 2010 06:42:04 +0000 (UTC)
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I'm having some trouble differentiating a curve I have. I don't really understand the command but I've got a plot of the Density in a lake and I need to find the derivative at a certain point. I've fit a ninth order polynomial to it but it's a horrbile fit, yet nothing else gets close and I need this to use this for the 'differentiate' command.

If anyone knows a little about this would you please give me a little guidance.

Thanks heaps