Struct rv::dist::Poisson

pub struct Poisson {
    pub rate: f64,
}

Possion distribution on unisgned integers

Example

extern crate rv;
extern crate rand;

use rv::prelude::*;

// Create Possion(λ=5.3)
let pois = Poisson::new(5.3).unwrap();

// CDF at 5
assert!((pois.cdf(&5_u16) - 0.56347339228807169).abs() < 1E-12);

// Draw 100 samples
let mut rng = rand::thread_rng();
let xs: Vec<u32> = pois.sample(100, &mut rng);
assert_eq!(xs.len(), 100)

Fields

rate: f64

Methods

impl Poisson

pub fn new(rate: f64) -> Result<Self>

Trait Implementations

impl Clone for Poisson

fn clone(&self) -> Poisson

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for Poisson

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

Formats the value using the given formatter.

impl Mean<f64> for Poisson

fn mean(&self) -> Option<f64>

Returns None if the mean is undefined

impl Variance<f64> for Poisson

fn variance(&self) -> Option<f64>

Returns None if the variance is undefined

impl Skewness for Poisson

fn skewness(&self) -> Option<f64>

impl Kurtosis for Poisson

fn kurtosis(&self) -> Option<f64>

impl Rv<u16> for Poisson

fn ln_f(&self, x: &u16) -> f64

Un-normalized probability function

fn ln_normalizer(&self) -> f64

The log of the constant term in the PDF/PMF. Should not be a function of any of the parameters.

fn draw<R: Rng>(&self, rng: &mut R) -> u16

Single draw from the Rv

fn sample<R: Rng>(&self, n: usize, rng: &mut R) -> Vec<u16>

Multiple draws of the Rv

fn f(&self, x: &X) -> f64

Un-normalized probability function

fn normalizer(&self) -> f64

The constant term in the PDF/PMF. Should not be a function of any of the parameters.

impl Support<u16> for Poisson

fn contains(&self, x: &u16) -> bool

Returns true if x is in the support of the Rv

impl DiscreteDistr<u16> for Poisson

fn pmf(&self, x: &X) -> f64

Probability mass function (PMF) at x

fn ln_pmf(&self, x: &X) -> f64

Natural logarithm of the probability mass function (PMF)

impl Cdf<u16> for Poisson

fn cdf(&self, x: &u16) -> f64

The value of the Cumulative Density Function at x

fn sf(&self, x: &X) -> f64

Survival function, 1 - CDF(x)

impl Rv<u32> for Poisson

fn ln_f(&self, x: &u32) -> f64

Un-normalized probability function

fn ln_normalizer(&self) -> f64

The log of the constant term in the PDF/PMF. Should not be a function of any of the parameters.

fn draw<R: Rng>(&self, rng: &mut R) -> u32

Single draw from the Rv

fn sample<R: Rng>(&self, n: usize, rng: &mut R) -> Vec<u32>

Multiple draws of the Rv

fn f(&self, x: &X) -> f64

Un-normalized probability function

fn normalizer(&self) -> f64

The constant term in the PDF/PMF. Should not be a function of any of the parameters.

impl Support<u32> for Poisson

fn contains(&self, x: &u32) -> bool

Returns true if x is in the support of the Rv

impl DiscreteDistr<u32> for Poisson

fn pmf(&self, x: &X) -> f64

Probability mass function (PMF) at x

fn ln_pmf(&self, x: &X) -> f64

Natural logarithm of the probability mass function (PMF)

impl Cdf<u32> for Poisson

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

The value of the Cumulative Density Function at x

fn sf(&self, x: &X) -> f64

Survival function, 1 - CDF(x)