On 07/24/2016 03:55 AM, Samy Ould-Chikh wrote:
I have some issue to import a file in Athena: just a simple x-y column (.txt
attached with this email).
Data range in the file : 4916.30 up to 5436.88 eV.
Issue: only data up to 5260 eV are imported (see screenshot: bug-importation).
Version: Demeter 0.9.24
System: Windows 7 Professional SP1
Well, I hope it's just not me not being able to find a proper way to import the
I have a hard time imagining the need for an XAFS scan with 12000 data
points. That will usually provides a point density that about an order
of magnitude below the core-hole lifetime, maybe 2. In your case, it
corresponds to about 0.04 eV steps, which seems silly to me. While I'm
quite open to being convinced otherwise, I cannot believe that setting
up a scan this way is actually necessary.
But, more to the point, I think it is very unprofessional of the
beamline staff to send you home with data in a format that is so hard to
Athena does a pretty good job of importing data in all the crazy-ass
formats that beamlines around the world use. But it's not really fair
to expect that she can handle anything you can throw at her. If a
beamline presents data in a format that is not easy to interpret, it
should provide tools for converting the data to a format that can
reasonably be interpreted.
In your case, the beamline should provide you with a way to rebin the
data either onto a more coarse grid or onto something like a
"conventional" EXAFS grid.
So ... what I recommend, if you want to use Athena (*), is that you find
some way to rebin your data onto a grid that fits within the 8192 limit.
Athena's rebinning tool uses a simple box car average -- that would
suit your data just fine.
If you don't know what a box car average is, a google search for "box
car average excel", "box car average matlab", "box car average python",
etc... should provide a hint. Once you do that, Athena should behave
(*) Or use Athena with Larch. Larch does not have the 8192 limit. But
you should still process the data onto a sensible grid.
Bruce Ravel ------------------------------------ bra...@bnl.gov
National Institute of Standards and Technology
Synchrotron Science Group at NSLS-II
Building 743, Room 114
Upton NY, 11973
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