changing spacegroups

[Pete Dunten]

>DOES ANYONE KNOW OF A PROGRAM WHICH WILL CONVERT A MOSFLM PROCESSED P1
>DATA SET AND CONVERT IT TO A HIGHER ORDER SPACEGROUP, i.e P2?

>yesterday i asked if anyone knew of a program which would
>change the spacegroup of a data set.  the CCP4 program "REINDEX" was
>called to my attention.  


This is not a reindexing problem, it is a problem of merging 
the symmetry-related reflections, taking into account the proper spacegroup.

There seem to be 2 possibilities.
1) Merge the data using scala and agrovata.   You'll have more symmetry-
related reflections in P2 than in P1, improving the scaling.  

2) Throw away half the data, with for example sftools, keeping only one
set of the unique reflections.  I don't recommend this option, even if it
is much faster.  

Cheers, Pete