## Re: [PyMOL] asymmetric transformation matrices

 Re: [PyMOL] asymmetric transformation matrices From: Tsjerk Wassenaar - 2009-11-09 08:22:15 ```Hi Thomas, Say, the first system is x and the second y, where y=R(x+s) is the first transformation. Then the reverse transformation follows as y = R(x + s) y = Rx + Rs Rx = y - Rs x = t(R)(y-Rs) Note that that is also equal to: x = t(R)y - s Hope it helps, Tsjerk On Mon, Nov 9, 2009 at 1:09 AM, Thomas Evangelidis wrote: > Dear pymol users, > > I noticed something strange when superimposing 2 opposite pairs of > chains. E.g. > > DEBUG: template  1BQG_A  query  2MUC_A > Query Transformation: >         X2 = +0.86747*(X1+2.29751) + -0.49574*(Y1+60.99794) + > -0.04181*(Z1+64.71239) >         Y2 = -0.49701*(X1+2.29751) + -0.85983*(Y1+60.99794) + > -0.11697*(Z1+64.71239) >         Z2 = +0.02204*(X1+2.29751) + +0.12225*(Y1+60.99794) + > -0.99226*(Z1+64.71239) > > > DEBUG: template  2MUC_A  query  1BQG_A > Query Transformation: >         X2 = +0.86747*(X1+30.95128) + -0.49701*(Y1+61.15895) + > +0.02204*(Z1+56.70381) >         Y2 = -0.49574*(X1+30.95128) + -0.85983*(Y1+61.15895) + > +0.12225*(Z1+56.70381) >         Z2 = -0.04181*(X1+30.95128) + -0.11697*(Y1+61.15895) + > -0.99226*(Z1+56.70381) > > Although looking at the rotation matrices one is the transpose of the > other, the translation vectors are not opposite. Can someone explain > that? > > > > ------------------------------------------------------------------------------ > Let Crystal Reports handle the reporting - Free Crystal Reports 2008 30-Day > trial. Simplify your report design, integration and deployment - and focus on > what you do best, core application coding. Discover what's new with > Crystal Reports now.  http://p.sf.net/sfu/bobj-july > _______________________________________________ > PyMOL-users mailing list (PyMOL-users@...) > Info Page: https://lists.sourceforge.net/lists/listinfo/pymol-users > Archives: http://www.mail-archive.com/pymol-users@... > -- Tsjerk A. Wassenaar, Ph.D. Junior UD (post-doc) Biomolecular NMR, Bijvoet Center Utrecht University Padualaan 8 3584 CH Utrecht The Netherlands P: +31-30-2539931 F: +31-30-2537623 ```