John R. Horton wrote:
I've tried several ways to get an Rfree flag into my mtz file...converting from a CNS to mtz (with existing flags) and scalepack to mtz and etc etc...with the same result, i.e. that the "bin number" that the reflection is in (0-19) is put in mtz file as the Rfree flag and not 0 or 1. I was wondering if this has to do with array size or something. This is a 1.42A dataset with 125982 reflections.
In MTZ files, free-R flags are usually from 0-19 (or 0-N, if you are not using a 5% free set).
There is a good reason for this - if you are not sure whether your FreeR is meaningful or not, you can re-run your structure solution using a different, non-overlapping FreeR set just by telling each individual program to use a set other than 0 as the test set. By this means you can do a full cross-validation.
Has anyone ever used this in practice? I don't know. But it is a good design feature.
