Note: the rand
crate now has built-in-support for the Alias method, so this library is no longer needed.
A Rust implementation of roulette wheel selection using the Alias Method. This can be used to simulate a loaded die and similar situations.
Initialization takes O(n) time; choosing a random element takes O(1) time. This is far faster than naive algorithms (the most common of which is commonly known as 'roulette wheel selection'). For an in-depth explanation of the algorithm, see http://www.keithschwarz.com/darts-dice-coins/.
This code was translated from http://www.keithschwarz.com/interesting/code/?dir=alias-method.
Example
Run example with cargo run --example simple
extern crate rand;
extern crate roulette;
use Roulette;
In this example, rand
will be 'a' with 40% probability, 'b' with 40% probability, and 'c' with 20% probability.