Re: nonlinear fit
- To: mathgroup at smc.vnet.net
- Subject: [mg41652] Re: nonlinear fit
- From: Bill Rowe <listuser at earthlink.net>
- Date: Thu, 29 May 2003 08:14:47 -0400 (EDT)
- Sender: owner-wri-mathgroup at wolfram.com
On 5/28/03 at 4:57 AM, entolonen at utep.edu (Tolonen, Ellen N) wrote:
>I am trying to implement the nonlinear fit on a set of experimental
>data. However, I am experiencing a bit of trouble with the definition
>of the function --
>
>Which is the proper Mathematica representation 1 = x^2 + y^2 - z^2, or
>y = Sqrt(1 - x^2 + z^2)?
Niether are proper representations of function in Mathematica. The first will generate an error message since Mathematica cannot assign a value to the constant 1. The second simply assigns the rhs to the variable y. The second expression can be used as the equivalent of a function using rules as in y/.{z->2, x->4}.
It isn't clear to me what form your data is in and what model you are trying to fit to your data. Consequently, I can't determine what form you need things in.