HOW TO DO How do I change the parameters of a force? vector forces = integrator->getForeGroup()->getForces(); // or Force* hf = new HarmDihedralSystemForce(2,0.3,true); report << hf->getId() <<":"<getParameters()[1].value << endr; string err; hf->setParameter(err,"-angle",0.5); report << hf->getId() <<":"<getParameters()[1].value << endr; hf->setParameter(err,1,0.7); report << hf->getId() <<":"<getParameters()[1].value << endr; delete hf;