Dear Bruce, Dear All, maybe it is a naïve question but I want to ask and to point this
There are a few questions all mixed together here. Why does Athena make a merge of references? As Matt points out, that is an odd thing to do. I decided I wanted some kind of reference channel tied to the merged spectrum so that I could take merged data from different project files and figure out how to align them in a consistent manner. The easiest way to do this was to tie something to the merged spectrum as its reference channel. I decided to make a merge of the reference spectra to serve this purpose. That was just a decision -- I could just as well have made a copy of the reference of the first spectrum in the merge list. So what explains the behavior Darek is asking about? Well, Athena doesn't actually make a serious distinction between data and its reference. They are both treated normal dtaa groups internally. The sense in which the reference is somehow special is that you, the user, tend not to look at it after you have done data alignment. So, when you make a merge, Athena sums up all the marked groups. Then, if ach one has a reference tied to it, it sums up the references and then ties together these two merged spectra. However, the reference tying runs both ways. If you change the energy shift for one, the other's energy shift changes the same way. In that sense, there is *no* difference between data and a reference. So, if you make a merge of data, ther references get merged into a merged reference. If you make a merge of references, the data get merged as well. The data groups that are maked get called "merge". The merge of the tied groups gets called " Ref merge". If you do the merge of the reference channels, these two merged groups get labeled backwards. I think that explains everything.... B On Thursday 19 November 2009 07:45:14 am Zajac, Dariusz A. wrote: problem...
Windows XP. Athena 0.8.059 Sc.Linux. Athena 0.8.060
I have a set of data with refernces (one sample, many scans). I have marked sample's groups and do "merge marked data in mu(E)" then I get merged data together with reference (2 groups: merge - sample, and Ref merge - reference). But... ...if I have marked reference sample's groups and do "merge" then I
get 2
groups: merge - which is merged data of reference, and Ref merge - which is marged data of sample. Oposite to that I did in first example!
Is any hidden idea, I can not see, why it should be that way? If you don't know about that, can confuse and surprise... cheers darek ___________l____________________________________ Ifeffit mailing list Ifeffit@millenia.cars.aps.anl.gov http://millenia.cars.aps.anl.gov/mailman/listinfo/ifeffit
-- Bruce Ravel ----------------------------------- bravel@bnl.gov National Institute of Standards and Technology Synchrotron Measurements Group, Beamlines X23A2, X24A, U7A Building 535A, Room M7 Brookhaven National Laboratory Upton NY, 11973, USA My homepage: http://xafs.org/BruceRavel EXAFS software: http://cars9.uchicago.edu/~ravel/software/exafs/