On Tue, 2005-05-24 at 11:34 +0200, Grégori Gerebtzoff wrote: > 3) define two interlaced loops and calculate the distance between all 6 > carbons of Phe1 with all 6 carbons of Phe2, either with cmd.dist or with > simple mathematical functions; sum these distances > > 4) divide the result by 36, and export the data!
Or more simply, once you have selected the 12 atoms, calculate the centroids of each of the two rings. Then just compute the distance between these centroids. This is a bit more efficient than doing 36 pairwise distances. Gareth