Re: Nonlinear Fit
- To: mathgroup at smc.vnet.net
- Subject: [mg59897] Re: Nonlinear Fit
- From: "Jens-Peer Kuska" <kuska at informatik.uni-leipzig.de>
- Date: Thu, 25 Aug 2005 06:33:31 -0400 (EDT)
- Organization: Uni Leipzig
- References: <dehilr$buv$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Hi,
and
Test[x1_?NumericQ,a1_?NumericQ]:=x1*NIntegrate[a1*x^3,{x,0,100}]
does what you expect ?
Regards
Jens
"Kevin Towles" <kbt22 at drexel.edu> schrieb im
Newsbeitrag news:dehilr$buv$1 at smc.vnet.net...
|I am trying to do a nonlinear fit of a function
that contains a
| numerical integration. My problem is that when
I call the nonlinear
| fit, it tries to evaluate within the nonlinear
fit call. For example:
|
| Test=Function[{x1,a1},
| NIntegrate[a*x^3,{x,0,100}]
| ];
|
| NonlinearFit[data,Test[x,a],x,{a,0,1}]
|
| Here I have a variable x and a parameter a.
This would return an
| NIntegrate error saying that 'NIntegrate is not
numerical at x={50.}'
| because there is an unknown, a, in the
integration.
|
| It tries this a couple times and then shuts off
the functioning of
| NIntegrate for further calculations, making
fitting this impossible.
| Is there a way to fit this kind of situation
without having the test
| function evaluate prior to fitting occuring?
|
| Thanks for any help,
|
| Kevin Towles
|
|