From: Peter (
Date: Tue Mar 26 2024 - 17:04:45 CDT

Hello everyone,

I tried selecting CA atoms within a certain distance of the center of the
sphere but have not been able to do so. More specifically, the "atomselect"
command is not able to process the selection. Is there any way of resolving
this issue?


set allatoms [atomselect top all]

set centerofsphere [measure center $allatoms]

set caatoms [atomselect top "name CA within 22 of $centerofsphere"]

$caatoms writepdb selectedatoms.pdb