MathGroup Archive 2006

[Date Index] [Thread Index] [Author Index]

Search the Archive

Re: Problems of NonlinearFit

  • To: mathgroup at smc.vnet.net
  • Subject: [mg63698] Re: [mg63577] Problems of NonlinearFit
  • From: Qun wei <qunweiwq at gmail.com>
  • Date: Tue, 10 Jan 2006 01:48:53 -0500 (EST)
  • References: <200601061024.FAA14556@smc.vnet.net>
  • Sender: owner-wri-mathgroup at wolfram.com

Anybody knows how to solve this problem?

On 1/6/06, Gavin <qunweidart at yahoo.com> wrote:
> The model is something like
> B1=I1*Sum[Func[m],{m,n1}]
> B1=I2*Sum[Func[m],{m,n2}]
> B1=I3*Sum[Func[m],{m,n3}]
> Then B=B1+B2+B3
>
> Then I need to find the best value of I1, I2, I3, n1, n2, n3 to fit the data I have. But it's not working:( The message is like "General::ivar: 1.` is not a valid variable." , "FindFit::njnum: The Jacobian is not a matrix of numbers at ....", etc.
>
> If I give values to n1, n2, n3 and just fit to find I1, I2, I3, then it's working well. What do I need to do or should I use another fit?
>
> Thank you!
>
>


  • Prev by Date: Re: Re: Using a List for the Listplot x-labels
  • Next by Date: Re: Re: Performance improvement needed - Help.
  • Previous by thread: Problems of NonlinearFit
  • Next by thread: trouble with NDSolve