iotbx.reflection_statistics returns space group 195 for a scalepack 'no merge original index' .sca file for space group 123 (i.e space group 197)
the first line of the .sca file is 12 i23
You are right, this is a bug. Sorry. However, it went unnoticed because we usually supply the correct space group (along with the missing unit cell parameters) via --symmetry=some_other_file You could also use --unit_cell=10,20,30,90,90,90 --space_group=197 Mostly I prefer --symmetry because there is less of a chance to mistype. Also, quite often the space group in a reflection file is not correct anyway (e.g. P222 vs. P212121).
the CCP4 program scala can output a 'no merge original index' format file, which has all 24 i23 symmetry operators in the header - but iotbx.reflection_statistics cannot read that either
I think you should be able to use the .sca file with the --symmetry or --space_group option. I've never tried to work with scala 'no merge original index' files. If you could send me your files I will look into fixing both problems. Peter Zwart wrote:
Note that iotbx.reflection statistics itself performs a merging step, which is less sophisticated then those available in SCALA or scalepack. Therefor, it might be worthwile considering supplying merged data to iotbx.reflection_statistics.
That's right. The simple merging in the cctbx is meant to be a stop-gap measure. It is best to merge externally with a program specifically designed for this purpose. Thanks for reporting the bug! Cheers, Ralf