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Revision as of 19:46, 7 February 2008 by Kay (talk | contribs)

XDSSTAT is a home-brewn program that prints various statistics (that are not available from XDS itself) in the form of tables and images.


The program reads from a file written by CORRECT or XSCALE (default: XDS_ASCII.HKL).

As the output is long, it should be called as

xdsstat > XDSSTAT.LP

This will probably soon be changed to the XDS style.

The program may be called with two parameters which define the resolution range of data to be read:

xdsstat 20 3 > XDSSTAT.LP



  • statistics: for each frame: # reflections, # misfits, I, sigma(I), I/sigma(I), fraction of reflections observed, correlation with standard profiles, R_meas and # reflections used for R_meas, # unique reflections which only occur on this frame and would thus be lost if this frame were deleted from the dataset. These lines end with " L" which may be used for "grepping" them from XDSSTAT.LP ("grep ' L$' XDSSTAT.LP > L").
  • R-factors as a function of frame number difference (R[math]_d[/math] , see Diederichs K. (2006) Some aspects of quantitative analysis and correction of radiation damage. Acta Cryst D62, 96-101). These lines end with " DIFFERENCE" which may be used for "grepping" them from XDSSTAT.LP ("grep DIFFERENCE XDSSTAT.LP > D").


The following quantities mapped onto the detector surface:

  • misfits.pck: outliers identified in CORRECT. Useful e.g. to identify ice rings.
  • rf.pck: R-factor (very interesting)
  • anom.pck: anomalous signal (very interesting)
  • scales.pck: scale factors between symmetry-related reflections (very interesting)
  • nobs.pck: observed reflections (not very interesting)
  • rlps.pck: reciprocal lorentz factor (not very interesting)

These images are in the .pck format and may be visualized by VIEW.


The binary program is at [1]; a statically linked version is [2]. Before using the program, you have to set up a CCP4 environment, because it uses the CCP4 routines and files.

I (Kay dot Diederichs at uni-konstanz dot de) appreciate feedback.

The source code is in Fortran90 and requires a Fortran90-compiled CCP4 library, so few people are currently in a position to compile and link the program. I might opensource it someday, but preferably as part of the XDS distribution.