MathGroup Archive 2009

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

Search the Archive

Re: Help with an error with NonlinearModelFit, Mathematica 7.0


On 5/7/09 at 6:35 AM, mgao4793 at gmail.com (Anonymous) wrote:

>I'm trying to find a fit to a large set of data.

>Here are In[1], In[2].

>In[1] := {{421.1, 6591.10}, ...};

>(there are way more points, in fact there are 35 in total, but I
>don't want to list them.  All are real numbers.)

>In[2] := nlm = NonlinearModelFit[data, Log[ak^2 + bk + c], {a,b,c},
>k]

>Then mathematica gives an error that basically says that the
>function "is not a list of real numbers"

>Of course it is, so how do I fix this?

Are you sure? How did you verify there were no non-numeric
elements in your data?

Try doing Union[Head/@Flatten[data]] where data is the array you
are feeding into NonlinearModelFit. That will return a list of
all data types in the array. Does it contain anything other than
Integer, Real or Rational? If so, that is the problem.




  • Prev by Date: Errorlistplot and array of graphs
  • Next by Date: Replace specific element with specific value.
  • Previous by thread: Re: Help with an error with NonlinearModelFit, Mathematica 7.0
  • Next by thread: math glyphs from non-Mathematica font