Re: Fitting a function to a list (newbie)
- To: mathgroup at smc.vnet.net
- Subject: [mg21869] Re: Fitting a function to a list (newbie)
- From: "Kevin J. McCann" <kevin.mccann at jhuapl.edu>
- Date: Wed, 2 Feb 2000 22:54:25 -0500 (EST)
- Organization: Johns Hopkins University Applied Physics Lab, Laurel, MD, USA
- References: <872jej$civ@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
I believe that what you want is a least squares fit to your data. I have attached a NB at the bottom. Let me know if it helps. Kevin -- Kevin J. McCann Johns Hopkins University APL <mathprof at bigfoot.com> wrote in message news:872jej$civ at smc.vnet.net... > I'm new to Mathematica 4.0, so I apologize if this question is overly > trivial (and please let me know if there's a place for trivial > question). > > I have a list that I'd like to fit to the function: > > A + B*Sin[C*x+D] > > In other words, I'd like to find the (approximate numeric) values of > A,B,C,D that yield the best fit to my data. > > I tried using Fit[], but it only applies to linear combinations of > functions, and couldn't optomize the values of C and D. > > For this specific problem, I'm guessing some sort of Fourier transform > might work, but I'm interested in a more general solution -- for example > if Sin[] were replaced with a more complicated function. > > Any help appreciated! > > > Sent via Deja.com http://www.deja.com/ > Before you buy. > (*********************************************************************** Mathematica-Compatible Notebook This notebook can be used on any computer system with Mathematica 4.0, MathReader 4.0, or any compatible application. 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