def angle_to(self, other):
"""
Register this atom as angle partners. Cannot angle to itself. If that
is attempted, a BondError is raised
"""
if self is other:
raise BondError('Cannot angle atom to itself')
self._angle_partners.add(other)
other._angle_partners.add(self)
def dihedral_to(self, other):
"""
Register this atom as dihedral partners. Cannot dihedral to itself. If
that is attempted, a BondError is raised
"""
if self is other:
raise BondError('Cannot dihedral atom to itself')
self._dihedral_partners.add(other)
other._dihedral_partners.add(self)
def bond_to(self, other):
"""
Register this atom as bonded partners. Cannot bond to itself. If that
is attempted, a BondError is raised
"""
if self is other:
raise BondError('Cannot bond atom to itself')
self._bond_partners.add(other)
other._bond_partners.add(self)