[Ifeffit] Re: Another Artemis question

[Bruce Ravel]

On Wednesday 21 January 2004 04:05 pm, Tamas Varga wrote:
> 1. What's the exact definition of the R-factor used to evaluate the
> fractional misfit?

Read Chapter 5 of this document:

  http://cars9.uchicago.edu/feffit/feffit.ps

It's the old feffit manual, but the definitions of chi-square and
R-factor are the same.

> 2. Can Artemis fit just Fourier filtered raw data in k-space?

If I understand your question, then, yes.  On the data page in Artemis
there is a drop-down menu labeled "Fitting space".  One of the options
is "q".  In ifeffit-speak "q-space" means "Fourier filtered k-space".
We had to call it something.... ;-)

If I recall correctly, the back transform will be done over the
R-range and the fit will be done over the k-range of the original FT.

B



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