Special

lambert_w(x::Float64) -> Float64

\[y = W_0(x)\]

langevin(x::Float64) -> Float64

\[\mathcal{L}(x) = \coth(x) - x^{-1}\]

inverse_langevin(y::Float64) -> Float64

\[x = \mathcal{L}^{-1}(y)\]

rosenbrock(x, a::Float64, b::Float64) -> Float64

\[f(\mathbf{x}) = \sum_{i=1}^{N-1} \left[\left(a - x_i\right)^2 + b\left(x_{i+1} - x_i^2\right)^2\right]\]