On Jun 25, 2008, at 5:02 PM, Ben Webb wrote:
> Friedrich Foerster wrote: >> i spread imp throughout the world. even in exotic bavaria imp is >> functional now. >> here, i am trying ever more challenging things: i am using restraints >> from different sources and want to weight these terms differently. >> for >> that purpose, i want to employ a common strategy in x-ray: the >> different >> restraints are weighted according to the inverse magnitude of the >> corresponding derivatives. >> Do you know a way how to get the derivatives of a particle with >> respect >> to a specific restraint set in IMP. Particle.get_derivative uses the >> full scoring function as i understand it... > > It's not something that's immediately possible, as I see it, in IMP > currently. But I suppose you could go through every *other* restraint > and call set_is_active(false). Otherwise, if what you want to do is > precisely that - weight the restraints by the derivatives - then > perhaps > we could add extra functionality to the DerivativeAccumulator to allow > for that. To expand a little, it wouldn't be too hard to have the DA compute some metric on the derivatives it has been used to accumulate and then have a restraint set which looks at this value and uses it to compute its weight. The DA doesn't have any way of differentiating between different attributes though, in case that matters.