Struct fuzzcheck::mutators::vose_alias::VoseAlias

pub struct VoseAlias {
    pub original_probabilities: Vec<f64>,
    // some fields omitted
}

An efficient data structure to sample from a discrete, fixed distribution.

use fuzzcheck::mutators::vose_alias::VoseAlias;

// the discrete distribution is a vector of floats which must add up to 1.0
let probabilities = vec![0.5, 0.1, 0.2, 0.2];
// create the Vose alias. The `probabilities` vector is moved to `alias.original_probabilities`.
let alias = VoseAlias::new(probabilities);

// index has a 50% chance of being 0, 10% chance of being 1, 20% chance of being 2, and 20% chance of being 2
let index = alias.sample();

assert!((0 .. 4).contains(&index));

Fields

original_probabilities: Vec<f64>

Implementations

impl VoseAlias

pub fn new(probabilities: Vec<f64>) -> VoseAlias

Create a new Vose alias with the given discrete probability distribution.

Important: the probabilities must sum up to ~ 1.0

pub fn sample(&self) -> usize

Sample the Vose alias.

It returns an index within 0 .. original_probabilities.len().

Trait Implementations

impl Clone for VoseAlias

fn clone(&self) -> VoseAlias

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for VoseAlias

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl PartialEq<VoseAlias> for VoseAlias

fn eq(&self, other: &Self) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

This method tests for !=.