[gmx-users] initial velocities Langevin dynamics

[Mark Abraham]

Loris Moretti wrote:
> Dear Mark,
> 
> Thanks for answering! My question arises because in the manual is also reported that gen_vel "is only meaningful with integrator md" (mdp options section: velocity generation) 

Well it is much more effective to say that the first time. :-) Getting 
someone's attention to donate their time to you is more likely if you 
demonstrate that you've actively tried to find the answer. My reaction 
to your first post a week (or so) ago was to wonder why you hadn't 
looked in the manual. :-) This time, I actively pointed you at the 
manual, but now I find I didn't need to spend that time. This sort of 
thing can frustrate people who'd otherwise be happy to help. Do have a 
look at the link at the bottom of this page 
http://wiki.gromacs.org/index.php/Support

> and because I provide a .gro file with no velocities and I clearly specify in the .mdp not to generate velocity.

If there's no source of velocities, then probably zero gets used for 
initial velocities.

> Thus I am a bit confused about it!

I'm confused about the manual comment about only being meaningful with 
the MD integrator, but we'll have to wait until someone who knows 
something about LD can post!

Mark