The Lambert W function, given an input z, outputs w such that z = w
exp(w). A numerical algorithm of order 4 is used to find the zero of z -
w exp(w).
Usage
lambertw(z)
Arguments
z
the argument of the Lambert W function
Value
Returns the value of the Lambert W function.
References
Corless, R. M., Gonnet, G. H., Hare, D. E. G., Jeffrey, D. J. and Knuth,
D. E. (1996), On the Lambert W Function, 5, Advances in Computational
Mathematics