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Re: Using FindFit with constraints ??

• To: mathgroup at smc.vnet.net
• Subject: [mg75701] Re: [mg75655] Using FindFit with constraints ??
• From: Carl Woll <carlw at wolfram.com>
• Date: Wed, 9 May 2007 04:20:27 -0400 (EDT)
• References: <200705080945.FAA18382@smc.vnet.net>

Alex wrote:

>Hello everybody,
>
>I saw at http://reference.wolfram.com/mathematica/ref/FindFit.html
>that FindFit can be used with constraints for the parameters. However
>when I try the example with Mathematica 5.2 I get an error.
>
>  
>
The problem is that you are looking at version 6 documentation and 
expecting version 5.2 to have the same functionality. FindFit with 
constraints is a new version 6 feature.

Carl Woll
Wolfram Research

>model = a Cos[=CF=89 t];
>data = Table[{t, Cos[2.1 t]}, {t, 0, 10, .25}] + RandomReal[.1, 41];
>fit = FindFit[data, {model, {a > 0, 1 < =CF=89 < 2}}, {a, =CF=89}, t]
>
>=>
>FindFit::nlnum: The function value {-1. + Cos[RandomReal[0.1, 41.]] -
>\
>1=2E\RandomReal[0.1, 41.], \[LeftSkeleton]9\[RightSkeleton], \
>[LeftSkeleton]113\
>\[RightSkeleton]} is not a list of numbers with dimensions {123} at
>{a, =CF=89} = \
>{1, 1}.
>
>
>What am I doing wrong ??
>
>Alex
>
>  
>

• References:
  • Using FindFit with constraints ??
    • From: Alex <axel.kowald@rub.de>