PHP Класс MathPHP\Probability\Distribution\Continuous\LogNormal

Наследование: extends Continuous

Открытые методы

Метод	Описание
CDF ( number $x, number $μ, number $σ ) : number	Log normal distribution - cumulative distribution function
PDF ( number $x, number $μ, number $σ ) : number	Log normal distribution - probability density function
mean ( number $μ, number $σ ) : number	Mean of the distribution

https://en.wikipedia.org/wiki/Log-normal_distribution 1 1 / ln x - μ \ cdf = - + - erf | -------- | 2 2 \ √2σ /

public static CDF ( number $x, number $μ, number $σ ) : number
$x	number	> 0
$μ	number	location parameter
$σ	number	scale parameter > 0
Результат	number

https://en.wikipedia.org/wiki/Log-normal_distribution (ln x - μ)² 1 - ---------- pdf = ----- ℯ 2σ² xσ√2π

public static PDF ( number $x, number $μ, number $σ ) : number
$x	number	> 0
$μ	number	location parameter
$σ	number	scale parameter > 0
Результат	number

μ = exp(μ + σ²/2)

public static mean ( number $μ, number $σ ) : number
$μ	number
$σ	number
Результат	number