Hi Everyone, I am using Larch for reading and fitting EXAFS data and I get the autobk and Fourier transforms working. But when I try to generate the fefffpaths and fit the data I get an error from the feffit function. I am using the developer version of Larch on MC OS Catalina. Below is the error and the sample script- runfile('/Users/rachita/Box/Larch/Feff_Try2/001.py', wdir='/Users/rachita/Box/Larch/Feff_Try2') Traceback (most recent call last): File "/Users/rachita/Box/Larch/Feff_Try2/001.py", line 27, in <module> fit = feffit(params, dset) File "/Users/rachita/opt/anaconda3/lib/python3.8/site-packages/xraylarch-0.9.50-py3.8.egg/larch/xafs/feffit.py", line 534, in feffit ds.prepare_fit(params=params) File "/Users/rachita/opt/anaconda3/lib/python3.8/site-packages/xraylarch-0.9.50-py3.8.egg/larch/xafs/feffit.py", line 265, in prepare_fit ikmax = int(1.01 + max(self.data.k)/trans.kstep) AttributeError: 'AthenaGroup' object has no attribute ‘k’ #tried this with xdi format data and got the same error Below is the script - #!/usr/bin/env python3 # -*- coding: utf-8 -*- from larch.fitting import param_group, Parameter from larch.io http://larch.io/ import read_xdi from larch.xafs import feffpath, feffit_dataset, feffit_transform, feffit, feffit_report data = read_xdi('cu_metal_rt.xdi’) #I tried importing Athena project file too path1 = feffpath('feff0001.dat', s02='amplitude', e0='del_e0', sigma2='sigma2', deltar='del_r') trans = feffit_transform(kmin=3, kmax=16, kw=(2,1,3), dk=1, window='hanning', rmin=1.7, rmax=3.1) params = param_group(amplitude= Parameter(1, vary=True), del_e0 = Parameter(1e-7, vary=True), del_r = Parameter(1e-7, vary=True), sigma2 = Parameter(0.003, vary=True)) dset = feffit_dataset(data=data, pathlist=[path1], transform=trans) fit = feffit(params, dset) print(feffit_report(fit)) By printing path groups and transform fit, I confirmed that the data is read correctly. Please let me know if there are ways to fix this or if there is an error in my script. Thank You! Rachita