Re: [ccp4bb] Calculation of angle between two helix of different subunits

[Charlie Bond]

I've previously done it by using the centroids of the Calphas from the  
first 4 residues and last 4 residues of the helix to define the vector  
(7 residues might be better if the helix is long enough). It seemed to  
work well enough by eye.
From then on it is simple vector algebra (google 'dot product' or  
something similar).
Cheers,
Charlie
--
Charlie Bond
Professorial Fellow
University of Western Australia
School of Biomedical, Biomolecular and Chemical Sciences
M310,  35 Stirling Highway
Crawley WA 6009, Australia