Lipschitz bound inside a bounded analytic half-plane (source code)

= Lipschitz bound inside a bounded analytic half-plane

If $f$ is analytic and bounded by $K$ on $\operatorname{Re}z>0$, then Cauchy's derivative estimate gives
$$
|f'(z)|\leq K/c
$$
on $\operatorname{Re}z>c$. Integrating along line segments gives a Lipschitz bound with the same constant in that smaller half-plane.