(PECL stats >= 1.0.0)
stats_dens_pmf_negative_binomial — Probability mass function of the negative binomial distribution
Returns the probability mass at x
, where the
random variable follows the negative binomial distribution of which
the number of the success is n
and the success
rate is pi
.
x
The value at which the probability mass is calculated
n
The number of the success of the distribution
pi
The success rate of the distribution
The probability mass at x
or false
for failure.