Hi all,
I'm a new Chimera user. I'm performing some molecular dynamics with a more or less simple system with Amber,and now that I have them done, I would like to analyze some specific data,like changes in a dihedral angle during the dynamic process, or distances between pairs of atoms. If I select several dihedral angles in Chimera and I play the dynamic movie, I can see these changes, but is it possible to get a table of results that shows the value of this angle for each step of the dynamic process?
Hi Eduardo,
You can get this information by defining some actions to perform at each frame. To do this use MD Movie's Per Frame->Define Script... menu item. This will bring up a dialog that allows you to define Chimera commands or Python code to execute at each frame (controlled with the "Interpret script as..." menu at the top of the per-frame dialog). The Chimera command "angle" can be used to report dihedrals to the reply log, so something like:
angle #0:5@o4',c1',n9,c4
would report the specified dihedral angle to the reply log. Something similar can be done with the "distance" command but it's a little trickier since the distance command sets up a distance monitor and it won't let you set up a duplicate monitor, so you need to clear existing distance monitors first (with "~dist"). So something like this:
~dist all
dist #0:6@o4',h8
would report the given distance to the reply log. If you are reporting many distances/angles you might consider using the "echo" command to insert additional text into the reply log to help you keep track of things. Also, you can use the "help" command (e.g. "help echo") to get more info on any command.
I hope this helps.
--Eric