[][src]Crate zipf

A fast generator of discrete, bounded Zipf-distributed random numbers.

For a random variable X whose values are distributed according to this distribution, the probability mass function is given by

P(X = k) = H(N,s) * 1 / k^s for k = 1,2,...,N

H(N,s) is the normalizing constant which corresponds to the generalized harmonic number of order N of s.


use rand::distributions::Distribution;

let mut rng = rand::thread_rng();
let mut zipf = zipf::ZipfDistribution::new(1000, 1.03).unwrap();
let sample = zipf.sample(&mut rng);

This implementation is effectively a direct port of Apache Common's RejectionInversionZipfSampler, written in Java. It is based on the method described by Wolfgang Hörmann and Gerhard Derflinger in Rejection-inversion to generate variates from monotone discrete distributions from ACM Transactions on Modeling and Computer Simulation (TOMACS) 6.3 (1996).



Random number generator that generates Zipf-distributed random numbers using rejection inversion.