Mathematica 9 is now available
Services & Resources / Wolfram Forums / MathGroup Archive
-----

MathGroup Archive 2012

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

Search the Archive

Re: Fitting part of a List

  • To: mathgroup at smc.vnet.net
  • Subject: [mg127527] Re: Fitting part of a List
  • From: Bill Rowe <readnews at sbcglobal.net>
  • Date: Wed, 1 Aug 2012 04:57:51 -0400 (EDT)
  • Delivered-to: l-mathgroup@mail-archive0.wolfram.com
  • Delivered-to: l-mathgroup@wolfram.com
  • Delivered-to: mathgroup-newout@smc.vnet.net
  • Delivered-to: mathgroup-newsend@smc.vnet.net

On 7/30/12 at 10:14 PM, eppi2.0 at freenet.de (Butterfly87) wrote:

>I have a set of data(63 pairs) of the form {x-Value, Intensity}
>imported to Mathematica. I also managed to extract the data pairs 5
>to 25 using the Take-function. I want to fit these data using the
>Fitfunction TS[q] and FindFit. I told Mathematica to follow this
>Input: FindFit[d2[q], TS[q], {{a, 1000}, {b, 1500}, {c, 0.008}}, q]

You are using q for two distinct purposes:

1) as the independent variable for your model TS[q]
2) as a known parameter to select a portion of your data d2[q]

You cannot use q for both of these purposes in a single call to FindFit.

Also, be aware ds2[q] is the function evaluated at q, not a
selection for a subset of your data. It is possible to use the
notation ds2[q] as a subscripted variable. But unless you data
is different than what you seem to be describing (an n x 2
array), even if you use this correctly as a subscripted variable
you would be choosing a single data point which clearly won't work.




  • Prev by Date: Re: How do I create a circular lamina?
  • Next by Date: Re: How do I create a circular lamina?
  • Previous by thread: Re: Mathematica as a New Approach to Teaching Maths
  • Next by thread: Data Format