Struct GammaDistribution 

pub struct GammaDistribution {
    pub shape_parameter: f64,
    pub scale_parameter: f64,
    pub distribution_name: String,
    pub description: String,
}

Parameters of a Gamma distribution.

A flexible positive-support family generalising the exponential and chi-squared distributions, in the shape/scale parameterisation.

Fields

shape_parameter: f64

Shape parameter k; must be > 0.

scale_parameter: f64

Scale parameter θ; must be > 0. The mean is k·θ.

distribution_name: String

Optional human-readable name; unused by the numerics, defaults to empty.

description: String

Optional human-readable description; unused by the numerics, defaults to empty.

Trait Implementations

impl Cdf for GammaDistribution

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

Evaluates the cumulative distribution function at x.

impl Clone for GammaDistribution

fn clone(&self) -> GammaDistribution

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for GammaDistribution

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

Formats the value using the given formatter.

impl Default for GammaDistribution

fn default() -> GammaDistribution

Returns the “default value” for a type.

impl Moments for GammaDistribution

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

Returns the theoretical mean, or None if it is undefined.

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

Returns the theoretical variance, or None if it is undefined.

impl Pdf for GammaDistribution

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

Evaluates the probability density function at x.

impl Quantile for GammaDistribution

fn quantile(&self, p: f64) -> f64

Evaluates the quantile (inverse CDF) at probability p.

impl Sample for GammaDistribution

fn sample(&self, rng: &mut SplitMix64) -> f64

Draws one variate, advancing rng.