Dear Zhengfeng The simplest is to use the command line. There is a whole “atom specification" language for selecting or specifying certain models, chains, atoms. For example: select :200 select #0:200.A The first example selects all residues with number 200, the second example selects residue 200 in chain A of model 0. See “atom specification” description and many examples: <http://www.rbvi.ucsf.edu/chimera/docs/UsersGuide/midas/frameatom_spec.html> To learn more, you could try the “getting started” tutorials: <http://www.rbvi.ucsf.edu/Outreach/Tutorials/GettingStarted.html> <http://www.rbvi.ucsf.edu/chimera/docs/UsersGuide/tutorials/getting_started.html> You can also show Sequence from the Favorites menu and select with the mouse in the sequence window. <http://www.rbvi.ucsf.edu/chimera/docs/ContributedSoftware/multalignviewer/framemav.html> I hope this helps, Elaine ----- Elaine C. Meng, Ph.D. UCSF Chimera(X) team Department of Pharmaceutical Chemistry University of California, San Francisco
On Jun 13, 2018, at 3:01 AM, 张征锋 <zhengfeng@mail.ccnu.edu.cn> wrote: Dear Sir, It is nice to use the amaizing software of UCSF Chimera. I can select a kind of residue such as all 'SER's and label them, while I am able to select a specified number of residue, such as the 200th residue 'Ser'. Could you please show me how to do with this? Thanks a lot. Best, zhengfeng