const double V2diff = pow(real(V), 2) - pow(imag(V), 2);
const double Vprod = real(V)*imag(V);
Y = complex<double> ( + real(Y) * V2diff + 2 * imag(Y) * Vprod,
- imag(Y) * V2diff + 2 * real(Y) * Vprod ) / norm(V);
#endif
const double V2diff = pow(real(V), 2) - pow(imag(V), 2);
const double Vprod = real(V)*imag(V);
Y = complex<double> ( + real(Y) * V2diff + 2 * imag(Y) * Vprod,
- imag(Y) * V2diff + 2 * real(Y) * Vprod ) / norm(V);
#endif