When you define a restraint, you choose the type of the restraint (like distance, angle etc) and the functional form how to restrain it. E.g. If the functional form defines only an upper boundary, you have a constraint.
For the various implemented functional forms check table 2.2. on p 74 in the manual.
a gaussian or an upper boundary gaussian (functional form 3 and 2) would be the answer for you. If you define a very small sigma for the G. function, you can imitate a hard limit, if it is desired. For options check MAKE_RESTRAINTS routine (therein: restraint_parameters).
Andras
Giulio Rastelli wrote: > > Dear modellers, > > is it possible with Modeller4 to define constraints instead of restraints? > I would like to constraint a set of conserved residues to be exactly in the > same position as those of the template structure, and was looking for a way > to do > this without setting explicit distance, angle and torsion restraints. > > Thank yuo very much, > > Giulio Rastelli > Dipartimento di Scienze farmaceutiche > Universita di Modena , Italy