def _apply_operator_JzKetCoupled(self, ket, **options):
        j = ket.j
        m = ket.m
        jn = ket.jn
        coupling = ket.coupling
        if m.is_Number and j.is_Number:
            if m <= -j:
                return S.Zero
        return hbar*sqrt(j*(j + S.One) - m*(m - S.One))*JzKetCoupled(j, m - S.One, jn, coupling)
dataset/ETHPy150Open sympy/sympy/sympy/physics/quantum/spin.py/JminusOp._apply_operator_JzKetCoupled/original