Function rgsl::randist::geometric::geometric

pub fn geometric(r: &Rng, p: f64) -> u32

This function returns a random integer from the geometric distribution, the number of independent trials with probability p until the first success. The probability distribution for geometric variates is,

p(k) = p (1-p)^k-1

for k >= 1. Note that the distribution begins with k=1 with this definition. There is another convention in which the exponent k-1 is replaced by k.