Re: [Ifeffit] Unwanted rescaling of energy axis when importing ascii file into Athena (Demeter 0.9.26)

2019-01-09 Thread Ravel, Bruce


Lukas,

A mistake is made related to the keV units in the first column of your 
data file.  This mistake is made only with the Ifeffit backend and only 
for data with keV energy units.  The Larch backend does not suffer from 
this problem.  Nor do data files with eV energy units.

I just checked a fix for this into github.  I hope to make a new windows 
release sometime soon ... it will have this fix.

Two possible work-arounds:

1. Use data files with eV energy units.  The problem only effects data 
measured in keV units.

2. If you cannot wait for a new Windows release, I can explain how to 
modify the relevant source code file to correct the mistake.  It would 
involve editing 3 lines of a file installed on your computer.

B

On 01/09/2019 09:35 AM, Lukas Grote wrote:
> Hello,
> 
> I am reporting an apparent bug in Athena (Demeter 0.9.26, Windows 10). 
> When I import high energy resolution XAS data from an ascii file, the 
> energy axis is automatically rescaled to 1.2eV step size, thus 
> drastically reducing the resolution of the data. When the imported data 
> has energy steps larger than 1.2eV, no rescaling occurs.
> 
> This issue may be similar to the one reported in March 2018 under the 
> topic "Athena (Demeter 0.9.26) does not import all datapoints from ascci 
> file". However, the issue I am seeing always results in 1.2eV steps in 
> the imported data. If my original file hast 0.3eV steps, the number of 
> points is reduced by a factor of 4. If it has 0.6eV steps, the number of 
> points is reduced by a factor of 2.
> 
> I couldn't find any option to switch this recaling on / off, or to 
> change the target energy step size.
> 
> The problem does not occur with Demeter 0.9.25. Attached please find two 
> screenshots of the data import dialog for both versions of Demeter. The 
> plots show the difference in energy scale. I also attached the original 
> data file "no_rebin.dat" as well as spectra exported from both Demeter 
> versions, one of them showing the 1.2eV steps.
> 
> Thank you and all the best,
> Lukas
> 
> -- 
> Lukas Grote
> 
> University of Hamburg
> Center for Hybrid Nanostructures
> Institute for Nanostructures and Solid State Physics
> Luruper Chaussee 149, Bld. 600, Room 2.62
> 22761 Hamburg
> Germany
> 
> +49 40 42838 1614
> 
> 
> 
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-- 
  Bruce Ravel   bra...@bnl.gov

  National Institute of Standards and Technology
  Synchrotron Science Group at NSLS-II
  Lead Beamline Scientist, 6BM (BMM)
  Building 743, Room 114
  Upton NY, 11973

  Homepage:http://bruceravel.github.io/home/
  Beamline:https://www.bnl.gov/ps/beamlines/beamline.php?r=6-BM
  Software:https://github.com/bruceravel
  Demeter: http://bruceravel.github.io/demeter/

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Re: [Ifeffit] Unwanted rescaling of energy axis when importing ascii file into Athena (Demeter 0.9.26)

2019-01-09 Thread Robert Gordon

Hi,

I switched your data from keV to eV before importing, and that does not 
have the same issue.


-R.

On 2019-01-09 6:35 a.m., Lukas Grote wrote:


Hello,

I am reporting an apparent bug in Athena (Demeter 0.9.26, Windows 10). 
When I import high energy resolution XAS data from an ascii file, the 
energy axis is automatically rescaled to 1.2eV step size, thus 
drastically reducing the resolution of the data. When the imported 
data has energy steps larger than 1.2eV, no rescaling occurs.


This issue may be similar to the one reported in March 2018 under the 
topic "Athena (Demeter 0.9.26) does not import all datapoints from 
ascci file". However, the issue I am seeing always results in 1.2eV 
steps in the imported data. If my original file hast 0.3eV steps, the 
number of points is reduced by a factor of 4. If it has 0.6eV steps, 
the number of points is reduced by a factor of 2.


I couldn't find any option to switch this recaling on / off, or to 
change the target energy step size.


The problem does not occur with Demeter 0.9.25. Attached please find 
two screenshots of the data import dialog for both versions of 
Demeter. The plots show the difference in energy scale. I also 
attached the original data file "no_rebin.dat" as well as spectra 
exported from both Demeter versions, one of them showing the 1.2eV steps.


Thank you and all the best,
Lukas

--
Lukas Grote

University of Hamburg
Center for Hybrid Nanostructures
Institute for Nanostructures and Solid State Physics
Luruper Chaussee 149, Bld. 600, Room 2.62
22761 Hamburg
Germany

+49 40 42838 1614

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# created: Wed Jan 09 09:11:08 2019
# from file: no_rebin.dat
# No: 300  [E0: 0,0,0,-1]
#-
#   X  Y
7.695000E+003  1.627000E-003
7.695300E+003  0.00E+000
7.695600E+003  0.00E+000
7.695900E+003  4.00E-006
7.696200E+003  0.00E+000
7.696500E+003  0.00E+000
7.696800E+003  0.00E+000
7.697100E+003  0.00E+000
7.697400E+003  1.90E-004
7.697700E+003  2.23E-004
7.698000E+003  0.00E+000
7.698300E+003  9.50E-005
7.698600E+003  0.00E+000
7.698900E+003  0.00E+000
7.699200E+003  5.13E-004
7.699500E+003  0.00E+000
7.699800E+003  0.00E+000
7.700100E+003  0.00E+000
7.700400E+003  0.00E+000
7.700700E+003  6.85E-004
7.701000E+003  0.00E+000
7.701300E+003  0.00E+000
7.701600E+003  1.212000E-003
7.701900E+003  1.252000E-003
7.702200E+003  0.00E+000
7.702500E+003  0.00E+000
7.702800E+003  0.00E+000
7.703100E+003  5.85E-004
7.703400E+003  0.00E+000
7.703700E+003  2.23E-004
7.704000E+003  0.00E+000
7.704300E+003  0.00E+000
7.704600E+003  0.00E+000
7.704900E+003  0.00E+000
7.705200E+003  0.00E+000
7.705500E+003  1.051000E-003
7.705800E+003  1.505000E-003
7.706100E+003  2.867000E-003
7.706400E+003  3.234000E-003
7.706700E+003  5.987000E-003
7.707000E+003  8.759000E-003
7.707300E+003  1.104000E-002
7.707600E+003  2.154400E-002
7.707900E+003  2.419700E-002
7.708200E+003  2.729500E-002
7.708500E+003  2.545500E-002
7.708800E+003  2.622900E-002
7.709100E+003  2.878800E-002
7.709400E+003  2.186200E-002
7.709700E+003  2.149500E-002
7.71E+003  1.581100E-002
7.710300E+003  1.294700E-002
7.710600E+003  1.238100E-002
7.710900E+003  1.489500E-002
7.711200E+003  1.502200E-002
7.711500E+003  1.729100E-002
7.711800E+003  2.015100E-002
7.712100E+003  1.776100E-002
7.712400E+003  2.071600E-002
7.712700E+003  2.291100E-002
7.713000E+003  3.075600E-002
7.713300E+003  3.416500E-002
7.713600E+003  3.863900E-002
7.713900E+003  5.061300E-002
7.714200E+003  6.470600E-002
7.714500E+003  8.677800E-002
7.714800E+003  9.986700E-002
7.715100E+003  1.247660E-001
7.715400E+003  1.407220E-001
7.715700E+003  1.752550E-001
7.716000E+003  2.023000E-001
7.716300E+003  2.324820E-001
7.716600E+003  2.891990E-001
7.716900E+003  3.340320E-001
7.717200E+003  3.657970E-001
7.717500E+003  4.208820E-001
7.717800E+003  4.632890E-001
7.718100E+003  5.094680E-001
7.718400E+003  5.573840E-001
7.718700E+003  6.133690E-001
7.719000E+003