[Ifeffit] fitting a specific k range
bravel at bnl.gov
Thu Dec 5 12:19:28 CST 2013
On 12/05/2013 12:18 PM, Scott Calvin wrote:
> While I defend that principle as a very important one, I'm not
> claiming it applies in Matt's case--it probably doesn't. To reproduce
> features at high-R, it IS necessary to have a model (i.e. paths) that
> cover the high-R contribution, and it sounds like Matt does not have
> those paths included in his model. But it's not necessary to FIT up
> to high R.
It doesn't apply. Matt filtered his data. Matt used paths that only
include Fourier components within the filtered band. To suggest that
it may somehow be reasonable that the fit could turn out other than
how it did runs a real risk of misleading this fellow who is,
apparently, a newcomer to EXAFS analysis.
> P.S. My least favorite warning that Artemis provides is the one that
> tells you that you're including paths outside the fitting region, for
> just this reason. It's easy enough to change the preferences so that
> Artemis doesn't give that warning, and it's usually one of the first
> things I have my students do when they're first learning to fit.
OK. Whatever. Instead of complaining about this, perhaps you should
consider hosannas of gratitude that I make it possible, easy even, to
accommodate preferences different from my own.
Bruce Ravel ------------------------------------ bravel at bnl.gov
National Institute of Standards and Technology
Synchrotron Science Group at NSLS --- Beamlines U7A, X24A, X23A2
Upton NY, 11973
More information about the Ifeffit