Hi Vijay, All "by"-operators have a weak priority, so you'll need an extra set of parenthesis there:
carb_pos = cmd.select('e. C and (byring e. C) and (pc.>0)') See also the yellow highlighted note about "Entity expansion" here: https://pymolwiki.org/index.php/Selection_Algebra Cheers, Thomas > On Feb 1, 2018, at 4:16 AM, Vijay Masand <vijaymas...@gmail.com> wrote: > > Dear PyMOL users, > Today, I used following command to select positively charged ring > carbon atoms, surprisingly, PyMOL 2.0.7 selected negatively charged > ring carbon atoms also. Is it a bug or issue associated with 'Byring'? > carb_pos = cmd.select('e. C and Byring e. C and (pc.>0)') > I am sharing the image for better understanding. > Cheers > Vijay -- Thomas Holder PyMOL Principal Developer Schrödinger, Inc. ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot _______________________________________________ PyMOL-users mailing list (PyMOL-users@lists.sourceforge.net) Info Page: https://lists.sourceforge.net/lists/listinfo/pymol-users Archives: http://www.mail-archive.com/pymol-users@lists.sourceforge.net