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Re: Fitting to complex values

  • To: mathgroup at smc.vnet.net
  • Subject: [mg30752] Re: Fitting to complex values
  • From: "Kevin J. McCann" <kevinmccann at Home.com>
  • Date: Sun, 9 Sep 2001 03:26:53 -0400 (EDT)
  • References: <9nalpb$npj$1@smc.vnet.net> <9ncgqf$q1g$1@smc.vnet.net>
  • Sender: owner-wri-mathgroup at wolfram.com

What about just doing a least squares fit? I have done this for complex data
and it works fine.

Kevin

"Lawrence A. Walker Jr." <lwalker701_remove_ at earthlink.net> wrote in message
news:9ncgqf$q1g$1 at smc.vnet.net...
> Hi Max,
>
> Try dividing the complex data into two data sets: real and imaginary.
> Then you can apply the NonlinearFit function twice.
>
> For example
>
> data = {{1, 1+2 I},{2, 3+4 I}, {3, 4+5 I}};
> dataRe=Map[{#[[1]],Re[#[[2]]]}&,data];
> dataIm=Map[{#[[1]],Im[#[[2]]]}&,data];
>
> NonlinearFit[dataRe, func1, ...];
> NonlinearFit[dataIm, func2, ...];
>
> Note, you must specify the functions apriori.
>
> Lawrence
>
>
> Max Ulbrich wrote:
>
> > Hi,
> >
> > I have complex data (re+im) from a lock-in amplifier and want to fit
> > them
> > to a complex function. Though, the NonlinearFit function doesn't work
> > with complex data. Has anyone a solution?
> >
> > Max
> >
> > mailto:ulbrich at biochem.mpg.de
> >
> >
> >
>



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