Constraints to parameters in FindFit?
- To: mathgroup at smc.vnet.net
- Subject: [mg51200] Constraints to parameters in FindFit?
- From: Jill Foley <efoley at princeton.edu>
- Date: Fri, 8 Oct 2004 02:54:48 -0400 (EDT)
- Sender: owner-wri-mathgroup at wolfram.com
Hi All, I am using FindFit to fit a series of peaks to some data. I would like to be able to constrain some of the parameters of my fit to correspond to physical reality. For example, some peaks should have a negative amplitude, others positive, where the amplitudes are the parameters that Mathematica is finding in FindFit. The peaks are all very near each other, so without any constraint, it is making the wrong ones negative. I'd like to specify that a given parameter should always be negative. I am already giving an initial guess of the proper sign, but it doesn't fix the problem. Please advise - Thanks! Jill.