[Ifeffit] Question about the R_factor in artemis/ifeffit

[Wayne Lukens]

Hi Bruce,

I calculated the R_factor by hand (well, by Excel, really) for the real 
component of the
Fourier transformed spectrum.  The analysis was actually carried out 
using Artemis, and
I calculated the R_factor over the fitting range in R.  For the real 
component, this was
exactly equal to the R_factor returned from Artemis.

I don't necessarily think that anything is wrong.  I was just curious 
about this.

Sincerely,

Wayne


On May 1, 2004, at 7:48 AM, Bruce Ravel wrote:

> On Friday 30 April 2004 06:33 pm, Wayne Lukens wrote:
>> First, thank you for the great software!  I am a former EXAFSPAK
>> user and have been really impressed by Artemis/ifeffit.  It's easier
>> to use, more flexible, and gives more reasonable errors for the fit
>> parameters.
>
> Well, welcome to the "family" and thanks for the kind words!
>
>> My question is about the value of the R_factor for R-space
>> fitting.   This seems to be the R_factor for the real component of
>> the Fourier transform only although the fitting is performed on both
>> the real and imaginary components.  Is there a reason that the
>> contribution of the imaginary component to the R_factor is not
>> included?
>
> A quick perusal of Matt's source code does not suggest that what you
> say is true.  Could you be more specific as to why you think that the
> R-factor is computed incorrectly?
>
> B
>
> -- 
>  Bruce Ravel  ----------------------------------- 
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>
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