The MoleculeRep class, defined in the Molecule module, is designed to make it easy to keep track of the reps in a molecule and to update reps in many molecules simultaneously. The way it works is to create a MoleculeRep instance, then add it to as many molecules as you want using the Molecule.addRep() method. The only operations on MoleculeRep objects is to change their properties; when this occurs, all molecules to which the rep has been added will be updated. Deleting a MoleculeRep instance has no effect. A list of MoleculeRep instances for a given molecule can be gotten from the Molecule.reps() method.
The MoleculeRep class provides the following methods:
In the following example, we load a molecule, add a new transparent VDW rep to the molecule, then change the atom selection for the rep to "name CA":
>>> from VMD import *
>>> from Molecule import *
>>> bR=Molecule()
>>> bR.load('../proteins/brH.pdb')
<snip>
>>> reps=bR.reps()
>>> reps[0].style
'Lines'
>>> vdw=MoleculeRep(style='VDW', material='Transparent')
>>> bR.addRep(vdw)
>>> vdw.changeSelection('name CA')