Friday, 10 August 2007

0.2.6.1 Buglet

If you find that perfectly correct indexing solutions are being rejected by the cell refinement test (with messages like "incorrect lattice constraints" you may have stumbled across a slight problem with the stability of the Moslfm cell refinement.

Previously I have used 1 (if tetragonal or higher, else 2) then 2, then 3 wedges for cell refinement. I found by jumping straight to 3 that the results are more reliable. However, on one test system and with one example the behaviour was completely wrong - it rejected a perfectly correct tetragonal solution with *very* high RMSD's. These are an artefact of unstable refinement.

If you remove the code:


# change 10/AUG/07 perhaps I should always be using
# three wedges?

Debug.write(
'Cell refinement: overriding the number of wedges to 3')

num_wedges = 3

from

$XIA2_ROOT/Wrapper/CCCP4/Mosflm.py

around line 768 everything should be fine. On windows this can be reached at

%XIA2_ROOT%/Wrapper/CCCP4/Mosflm.py

Any editor, even notepad, will be fine for this.

Sorry!

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