Hi Qingyu, On Fri, Mar 30, 2012 at 1:32 PM, KONG Quingyu wrote:

Thank you for all your helpful suggestions.

Actually, our beamline has recently installed a fast detector with a repetation of 20KHz, which could collected data in a time resolution of few tens of microsecond and could easily produce a large amount of data. We have already accepted three users for microsecond time resolved studies, each of them collected millions of spectra.

Together with the company that provide the detector and our software engineer we started to write a Python program to treat the data from November last year, however our engineer quitted recently, this make us to look for other solutions.

Bruce wrote earlier, As a closing comment, isn't it somehow strange that you and your colleagues went to all the trouble of building a fancy dispersive beamline without thinking ahead about how you were going to analyze your data? Sadly, Bruce's observation is not unusual at all. Everyone is experiencing data overloads, and almost no one is investing in computing resources. Yours may be slightly larger than most XAFS users, but only by one or two orders of magnitude. Then again, you had a software engineer at your beamline at least for a while. To be clear, Ifeffit, Athena, Demeter, Sixpack, and so on are written primarily by beamline scientists like yourself. Your choices are to use what someone else gives you, write your own, or hire someone to do it for you. It appears that the last choice rarely works very well. That you get to use Bruce's codes at all (and for free!) is not an accident: it is part of the design, and an outcome of the programs being written by beamline scientists. The current software base is more than ten years old, and showing its age especially with respect to large data sets and multiple processors. This is a really good opportunity for you and your colleagues (and others in similar situations) to join in. That is, you should write code to deal with your fast data rates. If you write that with the Ifeffit family of programs, not only will people at ESRF be able to use it, but so will anyone else.

If Demeter would works well for large amount of data treatment, it would be great. As I know ID24 at ESRF has also installed the same detector and would probably have similar demanding for such a program.

Looking into Demeter is one option, though I don't know exactly that is perfect for the linear combination analysis you want to use. Most of the core algorithms in Demeter still use Ifeffit 1.2, which are going to be limited for your needs, though they can be worked around if careful. Transferring Demeter to use the newer Ifeffit2 should be possible, but neither Bruce or I have done more than proof-of-principle tests. Looking into using Larch / IFeffit2 might be better for you, and I'd be happy to help you do that. For one thing, this approach has no memory limitations beyond your machine, is in Python and can read HDF5 files (which SOLEIL uses, as far as I understand) directly. It also has the possibility of using multicore machines well, but this has not yet been automated. It is also possible that the linear algebra techniques used for x-ray fluorescence map analysis, including code from Gerd Wellenreuther and Armando Sole would be useful for your needs.

Probably due to the limited memory of my pc, I can only open around 200 spectra simultanously with Athena.

You almost certainly want to not use Athena here anyway. You want automated processing programs. Like Bruce hinted at, you've invested heavily in a detector that allows you to collect data at a rate orders of magnitude faster than you could before. It would have been incredibly naive to believe that decade-old software would have been able to keep up with that. This is a good opportunity for you to help out yourself and others. Cheers, --Matt