Functions
template<typename ST = double>
ST	lambertW0 (ST z, int maxIterations=20, ST eps=std::numeric_limits< ST >::epsilon())
	Implementation of the principal branch of the Lambert-W function (branch 0 in the domain \( [- \dfrac{1}{e}, \inf) \) ), that is defined as the inverse function of \( f: x \mapsto xe^x \). It is defined for inputs of \( [- \dfrac{1}{e}, \inf) \). More...

Function Documentation

◆ lambertW0()

template<typename ST = double>

ST Ikarus::util::lambertW0	(	ST	z,
		int	maxIterations = `20`,
		ST	eps = `std::numeric_limits<ST>::epsilon()`
	)

The implementation uses Halley's iterative method and is inspired by https://github.com/JuliaMath/LambertW.jl/blob/master/src/LambertW.jl (licensed under MIT "Expat" License).

Template Parameters

ST	the ScalarType (defaults to double).

Parameters

z	the input value.
maxIterations	optionally define a maximmum of iteration.
eps	optionally define the epsilon of the iteration process (detuls to machine epsilon).