pub fn inv_norm_cdf<T: Passive, const K: usize>(x: &JetK<T, K>) -> JetK<T, K>
Inverse standard normal CDF Φ⁻¹(p). f' = 1/φ(f), f'' = f·f'².
Φ⁻¹(p)
f' = 1/φ(f)
f'' = f·f'²