def unit(self):
'''Normalize this vector to unit length.
@return: Normalised vector (L{Nvector}).
'''
if self._united is None:
u = NvectorBase.unit(self)
if u.datum != self.datum:
u._datum = self.datum
# self._united = u._united = u
return self._united
def unit(self, ll=None):
'''Normalize this vector to unit length.
@keyword ll: Optional, original latlon (C{LatLon}).
@return: Normalised vector (L{Nvector}).
'''
if self._united is None:
u = NvectorBase.unit(self, ll=ll)
if u.datum != self.datum:
u._datum = self.datum
# self._united = u._united = u
return self._united