[Ifeffit] artemis 0.6.001 and athena 0.8.016

Bruce Ravel ravel at phys.washington.edu
Mon Apr 21 12:17:05 CDT 2003


Hi folks!

Today I am pleased to announce the first version of Artemis that
supports multiple data set fitting.  That is, you can import 1 or more
data sets along with all the relevant feff calculations and use
parameters which impose constraints between the data sets.  

The second huge new feature in Artemis is something I call the Artemis
Project Assistant.  This is a wizard-like feature of the program which
helps you walk through the steps necessary to import one or more data
sets and one or more feff calculations and to set up fitting
parameters.  This will, I hope, reduce the difficulty and complexity
of getting started with Artemis.  I threw together a web page
explaining the Project Assistant:
   http://feff.phys.washington.edu/~ravel/software/exafs/apa.html
There are lots of pictures on that page as well as a step-by-step
recipe using the copper example that comes with the distribution.

The third big change has to do with how k-weighting is done for
fitting and plotting.  It is now possible to do a multiple k-weight
fit, that is to simultaneously fit data using, for example, both k=1
and k=3 weighting.  This is often helpful for distinguishing between
correlated variables which have different k dependence, such as
sigma^2 and S_0^2.  To explain how to use the various k-weighting
options in fits and in plots, see this web page:
    http://feff.phys.washington.edu/~ravel/software/exafs/kweight.html

I am looking forward to getting some feedback on this new version of
Artemis, both in terms of bug reports and in terms of suggestion for
user interface improvements.  The problem of organizing and presenting
a fit with multiple data sets and multiple feff calculations is very
difficult.  I have tried to present it in a way that is tractable, but
I am open to any suggestions any of you might have to make is better
and more clear.

As for Athena, 0.8.016 represents only a few small changes.  The most
important is that I fixed a very serious bug in the deglitching
interface.

As always, new tarballs and Windows executables are available on my
web site.  Please note that unix, linux, and OSX users must be running
at least version 1.0076 of Ifeffit.  If you have not updated the
Ifeffit core recently, please do so before installing the latest
tarball.

Thanks this time to Adam Webb for pointing out the deglitching bug in
Athena.  And a huge pile of thanks to Shelly Kelly for testing Artemis
last week and for making many great suggestions for improving the
Project Assistant and multiple data set fitting in general.


Regards,
Bruce


	
-- 
 Bruce Ravel  ----------------------------------- ravel at phys.washington.edu
 Code 6134, Building 3, Room 222
 Naval Research Laboratory                          phone: (1) 202 767 5947
 Washington DC 20375, USA                             fax: (1) 202 767 1697

 NRL Synchrotron Radiation Consortium (NRL-SRC)
 Beamlines X11a, X11b, X23b, X24c, U4b
 National Synchrotron Light Source
 Brookhaven National Laboratory, Upton, NY 11973

 My homepage:    http://feff.phys.washington.edu/~ravel 
 EXAFS software: http://feff.phys.washington.edu/~ravel/software/exafs/



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