(PECL stats >= 1.0.0)
stats_dens_beta — Probability density function of the beta distribution
$x
   , float $a
   , float $b
   ) : float
   Returns the probability density at x, where the
   random variable follows the beta distribution of which the shape parameters
   are a and b.
  
xThe value at which the probability density is calculated
aThe shape parameter of the distribution
bThe shape parameter of the distribution
   The probability density at x or FALSE for failure.