[IMP-users] does IMP.algebra.get_transformation_aligning_first_to_second minimize RMSD ?

Hi list,

Just confronted to something that looks like a bug, either in IMP or in my reading of the IMP manual. I'd expect the alignment of two sets of particles or vectors to minimize the RMD between the two sets, but in my case it appears the alignment produces a worse RMSD. See output underneath, and sample script attached.

Considering 30 3D vectors natural rmsd between v1 and v2: 209.651290894 aligning v1 on v2... with resulting rmsd 220.458206177 running IMP version kernel SVN 10177 with Boost.FileSystem