Using the PRJ (Win95/NT) Program by Andrew Jupe for Setting Up PRJ files Ready for Mass Analysis

The Problem and Solution - the Need for Speed!

In this case, we will use the trivial example of fitting Silicon patterns used for standardisation. The files are of a Silicon standard run on the Energy Dispersive Diffraction Beamline 16.4 and are included with the XFIT distribution kit. This dat is being used as other (better) data has yet to be published by their respective users.

• In XFIT, load a single data file, fit and optimise to this, save the project file (in this example called r01.prj).

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• Go into a DOS Window, then copy the r01.prj to another name (so you have a backup) as the PRJ program will be modifying the starting r01.prj file.

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• In this example, we want to look at every 3rd file and look at 15 of them at once within XFIT. We also want PRJ to correctly name the files that XFIT will want to use - with the starting file being r00001.dat. (by default, PRJ leaves the file name the same and allows the user to manually define which file names they wish to look at) (thus only the number 1 need be given). Now run PRJ using the following command line.

  (NB: Just running prj without any arguments gives you a small help result)
  

  C:\koalarie\XFIT-TUT\ENERGYD\SILICON\BOTTOM>prj
     Usage is:- [prj] [filename] [no. of data files]/
           (optional)[file number step size] (optional)[starting index]
           for HELP type "prj help"
  C:\koalarie\XFIT-TUT\ENERGYD\SILICON\BOTTOM>

  prj r01.prj 15 3 1

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• While PRJ is rather terse on output, you should now have a new r01.prj file that you can re-open in XFIT using the File, Load Project command which should now give you 15 files ready to do peak fitting on. Please note that at present, PRJ only can handle a start prj file that is fitting a single data file.

  Also refer to the tutorial: "When refining multiple files simultaneously Why does XFIT seem slower than usual? The people at the Royal Institution in London get around this problem by running multiple instances of XFIT; with each instance of XFIT loading roughly 6 data files (depending on the complexity of the peak fitting to be implimented).

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