code: def calcEL(self,**kwargs):
                                     
          E,L= calcELStaeckel(self._R,self._vR,self._vT,self._z,self._vz,
                              self._pot)
          return (E,L)
docs: NAME:
             calcEL
          PURPOSE:
             calculate the energy and angular momentum
          INPUT:
             scipy.integrate.quadrature keywords
          OUTPUT:
             (E,L)
          HISTORY:
             2012-11-27 - Written - Bovy (IAS)