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B
06/27/12 1:18pm

Thank you for the files, that makes all the difference when trying to get a correct answer on the first try, particularly for complicated problems.

Now, after a long wailing and gnashing of swap drive:

In[1]:= data2 = Import["218_c_2_a_life_norm.csv"];

In[2]:= f=Simplify[Exp[-x/R]*(1+Sum[((-48/100*x^(1-m))^n)*Hypergeometric1F1[-m*n,1+n-m*n,x/R]/Gamma[1+n-m*n], {n,1,1}])];

In[3]:= FindFit[data2,f,{R,m},x]

No more memory available.
Mathematica kernel has shut down.
Try quitting other applications and then retry.

If I try {n,1,5} or even {n,1,2} I get warnings about infinities. That almost always means that a zero has shown up in a denominator and any further calculations will be nonsense.

If I ListPlot your data over suitable ranges the data looks very clean and I would expect it might fit something substantially simpler than a sum of fifty HyperGeometric1F1's. Perhaps with some insight into the model of the data and suitable choice of a function to fit I think there is a good chance you can get a useful fit out of this.

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Subject (listing for 'Fitting Complicated functions')
Author Date Posted
Fitting Complicated functions Marcel 06/20/12 4:12pm
Re: Fitting Complicated functions Bill Simpson 06/24/12 00:25am
Re: Re: Fitting Complicated functions Marcel 06/24/12 5:00pm
Re: Fitting Complicated functions Bill Simpson 06/25/12 3:13pm
Re: Re: Fitting Complicated functions Marcel 06/27/12 06:46am
Re: Fitting Complicated functions B 06/27/12 1:18pm
Re: Re: Fitting Complicated functions Marcel 06/29/12 09:05am
Re: Re: Fitting Complicated functions Marcel 06/29/12 09:25am
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