stats_dens_pmf_poisson

(PECL stats >= 1.0.0)

stats_dens_pmf_poissonProbability mass function of the Poisson distribution

Descrierea

stats_dens_pmf_poisson ( float $x , float $lb ) : float

Returns the probability mass at x, where the random variable follows the Poisson distribution whose parameter is lb.

Parametri

x

The value at which the probability mass is calculated

lb

The parameter of the Poisson distribution

Valorile întoarse

The probability mass at x or FALSE for failure.