(PECL stats >= 1.0.0)

stats_cdf_poissonCalculates any one parameter of the Poisson distribution given values for the others


stats_cdf_poisson ( float $par1 , float $par2 , int $which ) : float

Returns the cumulative distribution function, its inverse, or one of its parameters, of the Poisson distribution. The kind of the return value and parameters (par1 and par2) are determined by which.

The following table lists the return value and parameters by which. CDF, x, and lambda denotes cumulative distribution function, the value of the random variable, and the parameter of the Poisson distribution, respectively.

Return value and parameters
which Return value par1 par2
1 CDF x lambda
2 x CDF lambda
3 lambda x CDF

Список параметров


The first parameter


The second parameter


The flag to determine what to be calculated

Возвращаемые значения

Returns CDF, x, or lambda, determined by which.