}
// inline double * get_Euler_angles_v() { return euler_angles_v; }
inline double get_Phi() const { return euler_angles_v[0]; }
inline double get_Theta() const { return euler_angles_v[1]; }
inline double get_Psi() const { return euler_angles_v[2]; }
}
// inline double * get_Euler_angles_v() { return euler_angles_v; }
inline double get_Phi() const { return euler_angles_v[0]; }
inline double get_Theta() const { return euler_angles_v[1]; }
inline double get_Psi() const { return euler_angles_v[2]; }