Re: [IMP-dev] Harmonic restraint on rotation in IMP

[Ben Webb <>]

On 3/25/14, 6:47 PM, Barak Raveh wrote:
> Does anybody know of an existing implementation of a harmonic restraint
> on rotational degrees of freedom?

Sure, this is essentially how an angle restraint works in the CHARMM 
forcefield, for example.

> Namely, I have two reference frame of two particles p1 and p2. For
> simplicity, assume xyz(p1) = xyz(p2). I would like to add a harmonic
> restraint over the delta in their reference frame, for some definition
> of that delta.

You just need to encode that delta (e.g. as a PairScore) then plug it 
into the existing framework. For example, see core::AngleTripletScore.

	Ben
--
                      http://salilab.org/~ben/
"It is a capital mistake to theorize before one has data."
	- Sir Arthur Conan Doyle