Struct mathru::stats::distrib::Poisson

pub struct Poisson { /* fields omitted */ }

Poisson distribution

Fore more information: https://en.wikipedia.org/wiki/Poisson_distribution

Methods

impl Poisson

pub fn new(gamma: &f64) -> Poisson

Creates a probability distribution

Arguments

• gamma gamma > 0.0

Panics

if gamma <= 0.0

Example

extern crate mathru;
use mathru::stats::distrib::Poisson;

let distrib: Poisson = Poisson::new(&0.2);

Trait Implementations

impl Discrete<u32, u32> for Poisson

fn pmf<'a>(&'a self, x: u32) -> f64

Probability mass function

Arguments

• x Random variable x ∈ ℕ

Example

extern crate mathru;
use mathru::stats::distrib::{Discrete, Poisson};

let distrib: Poisson = Poisson::new(&0.2);
let x: u32 = 5;
let p: f64 = distrib.pmf(x);

fn cdf<'a>(&'a self, x: u32) -> f64

Cumulative distribution function of the Bernoulli distribution

Arguments

• x Random variable x ∈ ℕ

Example

extern crate mathru;
use mathru::stats::distrib::{Discrete, Poisson};

let distrib: Poisson = Poisson::new(&0.2);
let x: u32 = 4;
let p: f64 = distrib.cdf(x);

fn mean<'a>(&'a self) -> f64

Expected value

Example

extern crate mathru;
use mathru::stats::distrib::{Discrete, Poisson};

let distrib: Poisson = Poisson::new(&0.2);
let mean: f64 = distrib.mean();

fn variance<'a>(&'a self) -> f64

Variance

Example

extern crate mathru;
use mathru::stats::distrib::{Discrete, Poisson};

let distrib: Poisson = Poisson::new(&0.2);
let var: f64 = distrib.variance();