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stats_rand_gen_gamma

(PECL stats >= 1.0.0)

stats_rand_gen_gamma — Generates a random deviate from the gamma distribution

说明

stats_rand_gen_gamma(float $a, float $r): float

Generates a random deviate from the gamma distribution whose density is (A**R)/Gamma(R) * X**(R-1) * Exp(-A*X).

参数

a

location parameter of Gamma distribution (a > 0).

r

shape parameter of Gamma distribution (r > 0).

返回值

A random deviate