[Ifeffit] How to change the data file in Dartemis?

[Bruce Ravel]

Robert:  Thanks for weighing in.

Isabelle: I apologize if it seems like I am ignoring you.  I was on 
travel for the majority of June and am very busy with things not related 
to software right now.  I simply haven't had time to look into your 
problem.  I'll get to it eventually.

B


On 07/07/2016 07:59 PM, Robert Gordon wrote:
> Hi Isabelle,
>
> If I understand your emails correctly, you are trying to fit two
> variations of a dataset (with different normalisations)
> to a given model FEFF calculation, yes? You have two different chi(k)'s.
> Rather than trying to replace.
> have you tried:
>
> Just fitting them one at a time in Artemis? i.e.  Import the first
> chi(k), set the FT parameters etc. Generate
> the FEFF model. Pick paths.  Set the GDS values. Save the project file.
> Run fit. Discard first data, import second
> set the FT parameters, select paths, enter the GDS values in the data
> window...(save again, perhaps as different
> fpj) and fit again?  (OK...this is replace, but by brute force)
>
> How about fitting both at the same time using the same FEFF model:
> Import both chi(k)'s and run two
> independent fits (i.e. amp1 for 1st, amp2 for 2nd etc) with the same
> FEFF calculation?
>
> I have tested both of these routes and they do work (though there is an
> issue with the Artemis [Plot] window
> dropping one of the datasets if it isn't being fit).
>
> regards,
> -R.
>
> On 7/7/2016 7:04 AM, Isabelle Kieffer wrote:
>> Dear Bruce, dear all,
>>
>> Just to add some input and precise my question.
>>
>> The problem I encounter with "replace this chi(k)" did not appear to
>> me until I tried to fit a spectrum twice with two different
>> normalisations. In this case, after a fit on the first spectrum, I
>> "replace this chi" with another that is normalised differently, and
>> when I try to fit, it stops with the following error message:
>>
>>      This data came from the the same source as another
>>      data group. You seem to be trying to increase your
>>      number of independent points by fitting the same data
>>      more than once in a multiple data set fit.
>>
>>
>> Seeing that, I wondered whether "replace this chi" was doing what I
>> thought. The upgrade did not change anything. I just tried with a
>> colleague working under windows and the result is also the same.
>>
>> Shall I do differently to fit those two really similar spectra?
>>
>> Thank you for your help,
>>
>> Isabelle
>>
>>
>>
>>
>> On 01/07/2016 21:08, Bruce Ravel wrote:
>>> On 07/01/2016 01:57 PM, Isabelle Kieffer wrote:
>>>> You mean that when you "Replace this chi(k)", it asks what to do, or it
>>>> supposes that you want to fit new data with the same model?
>>>
>>> What I mean is: upgrade.  Many of the problems you are reporting have
>>> been fixed already.  If you upgrade and still see these problems,
>>> make a bug report and I will look into it.
>>>
>>> B
>>>
>>>
>>
>
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-- 
  Bruce Ravel  ------------------------------------ bravel at 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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