Struct rand_distr::Normal

pub struct Normal<F> where
    F: Float,
    StandardNormal: Distribution<F>,  { /* fields omitted */ }

The normal distribution N(mean, std_dev**2).

This uses the ZIGNOR variant of the Ziggurat method, see StandardNormal for more details.

Note that StandardNormal is an optimised implementation for mean 0, and standard deviation 1.

Example

use rand_distr::{Normal, Distribution};

// mean 2, standard deviation 3
let normal = Normal::new(2.0, 3.0).unwrap();
let v = normal.sample(&mut rand::thread_rng());
println!("{} is from a N(2, 9) distribution", v)

Implementations

impl<F> Normal<F> where
    F: Float,
    StandardNormal: Distribution<F>, 

pub fn new(mean: F, std_dev: F) -> Result<Normal<F>, Error>

Construct, from mean and standard deviation

Parameters:

• mean (μ, unrestricted)
• standard deviation (σ, must be finite)

pub fn from_mean_cv(mean: F, cv: F) -> Result<Normal<F>, Error>

Construct, from mean and coefficient of variation

Parameters:

• mean (μ, unrestricted)
• coefficient of variation (cv = abs(σ / μ))

pub fn from_zscore(&self, zscore: F) -> F

Sample from a z-score

This may be useful for generating correlated samples x1 and x2 from two different distributions, as follows.

let mut rng = thread_rng();
let z = StandardNormal.sample(&mut rng);
let x1 = Normal::new(0.0, 1.0).unwrap().from_zscore(z);
let x2 = Normal::new(2.0, -3.0).unwrap().from_zscore(z);

Trait Implementations

impl<F: Clone> Clone for Normal<F> where
    F: Float,
    StandardNormal: Distribution<F>, 

pub fn clone(&self) -> Normal<F>

Returns a copy of the value.

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

Performs copy-assignment from source.

impl<F: Copy> Copy for Normal<F> where
    F: Float,
    StandardNormal: Distribution<F>, 

impl<F: Debug> Debug for Normal<F> where
    F: Float,
    StandardNormal: Distribution<F>, 

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

Formats the value using the given formatter.

impl<F> Distribution<F> for Normal<F> where
    F: Float,
    StandardNormal: Distribution<F>, 

pub fn sample<R: Rng + ?Sized>(&self, rng: &mut R) -> F

Generate a random value of T, using rng as the source of randomness.

pub fn sample_iter<R>(self, rng: R) -> DistIter<Self, R, T> where
    R: Rng, 

Create an iterator that generates random values of T, using rng as the source of randomness.