Hi Folks,

Larch 0.9.55 is now available for download.  This comes only two weeks after the announcement for 0.9.53, but there have been several important improvements especially for Windows users outside of the US, and based on bugs found or features requested during the Larch for XAFS Analysis Workshop at the Virtual XAFS 2021 conference (there was a 0.9.54, but a few things were fixed since then too!).  If you have installed a recent version of Larch and are on a machine connected to the internet, you should see a notice that version 0.9.55 is available, and can use that notice to automatically install the update.  That will be much faster than installing from the full installer.

A series of instructional videos made for this workshop on using Larch's XAS Viewer application for various aspects of XANES and EXAFS analysis are now publicly available at https://www.youtube.com/playlist?list=PLgNIl_xwV_vK4V6CmrsEsahNCAsjt8_Be.  Comments, questions, suggestions on these are most welcome, either on youtube or here.  For folks without access to youtube.com, these videos are also at  https://millenia.cars.aps.anl.gov/videos/XrayLarch/

The changes here are relatively minor compared to the changes made in 0.9.53 (see https://millenia.cars.aps.anl.gov/pipermail/ifeffit/2021-July/010251.html). The most important changes and fixes since 0.9.53 are:

  - Larch's GUI applications should again work without problems on non-US Windows 10 machines.  There was a serious bug (possibly since Larch 0.9.52) for using wxPython applications with Python>=3.8 and wxPython>=4.1.0.  I believe we have a workaround, at least for now.

 - Fixes for turning CIF structures into Feff inputs and running Feff:
    -- more external CIF files from Crystallography Open Database and Materials Project can be converted to Feff.inp.
    -- external Feff.inp files can be loaded and run.
    -- the name of the folder created for any Feff calculation can be renamed before running Feff.

 - the plot selection choice in the XAS normalization panel for "one group" and "selected groups" are no longer reset each time a data set is selected.

 - A reference spectrum can now be set for any XAFS spectrum.  When aligning or energy-shifting XAFS data, you can now easily select all of the spectra that share a reference and apply the same energy shift to those spectra.  You can also easily select a reference group for one XAS spectrum and copy that to a set of other "selected spectra".   There is not (yet?) a way to select a reference channel from a file when importing data, so these must be read separately and assigned.  

 - a bug was fixed on the EXAFS / background subtraction panel on "copied groups" to ensure that processing parameters (kweight, rbkg, etc) are kept separate.

 - For linear combination fitting, a single energy shift can be varied during the fit, shifting the unknown data to match the combination of a (presumably aligned) set of standards.

 - For pre-edge peak fitting and Feff Path fitting, entries in the "fit history" can have user-specified labels which can be more meaningful than the default "Fit #1", "Fit #2", etc.
  
 - testing is now done only with Github Actions, not with the appveyor service.

I want to thank all the people who took part in the workshop and gave feedback -- XAS Viewer is a lot better than it was a week ago.  Thanks to  Monica Bairagi and Nengchuan Tian for help, and special thanks to Klemen Bucar for helping track down and solving the Locale issue and working on the testing tools.  And also thanks to Mauro Rovezzi for continued suggestions and fixes.
If you have any questions, problems, or suggestions, please let me know.
--Matt