[ccp4bb] Reindexing Orthorhombic

[James Stroud]

Hello All,

I have two crystals (that I'll call "data set 1" and "data set 2")  
that seem to be isomorphic, but y and z are transposed between the two  
data sets. Reindexing data set 2 with the operators

  h => -h
  k => l
  l => k

makes the axes match data set 1, but running MR with the previous data  
set 2 solution on the newly reindexed data set 2 yields a solution  
rotated 180 about z with respect to the data set 1 solution. What is  
the operation to reindex such that real space is rotated 180 about z?  
These are in P212121.

James