P⃗,Q⃗,W⃗

def transform(self):
        '''P⃗,Q⃗,W⃗'''
        i = self.inclination
        Ω = self.longitude_of_ascending_node
        ω = self.argument_of_periapsis

        si = sin(i)
        ci = cos(i)
        sΩ = sin(Ω)
        cΩ = cos(Ω)
        sω = sin(ω)
        cω = cos(ω)

        Q = np.array([
             [-sΩ*ci*sω + cΩ*cω,
               cΩ*ci*sω + sΩ*cω,
               si*sω],
             [-sΩ*ci*cω - cΩ*sω,
               cΩ*ci*cω - sΩ*sω,
               si*cω],
             [ sΩ*si,
              -cΩ*si,
               ci]])

        return Q