Struct mathru::stats::distrib::Gamma

pub struct Gamma { /* fields omitted */ }

Gamma distribution

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

Methods

impl Gamma

pub fn new(p: &f64, b: &f64) -> Gamma

Creates a probability distribution

Arguments

• p (alpha) p > 0.0
• b (beta) b > 0.0

Panics

if p <= 0.0 || b <= 0.0

Example

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

let distrib: Gamma = Gamma::new(&0.3, &0.2);

Trait Implementations

impl Continuous<f64, f64> for Gamma

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

Probability density function

Arguments

• x Random variable x ∈ &#x2115 | x > 0.0

Panics

if x <= 0.0

Example

extern crate mathru;
use mathru::stats::distrib::{Continuous, Gamma};

let distrib: Gamma = Gamma::new(&0.3, &0.2);
let x: f64 = 5.0;
let p: f64 = distrib.pdf(x);

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

Cumulative distribution function

Arguments

• x Random variable

Example

extern crate mathru;
use mathru::stats::distrib::{Continuous, Gamma};

let distrib: Gamma = Gamma::new(&0.3, &0.2);
let x: f64 = 0.4;
let p: f64 = distrib.cdf(x);

fn quantile<'a, 'b>(&'a self, _p: f64) -> f64

Quantile function of inverse cdf

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

Expected value

Example

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

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

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

Variance

Example

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

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