This function returns the value of a student-T-distribution with the total area of 1.
$dfr are the degrees of freedom for that distribution (aka k)
$x is the X-Value for which the value should be returned
(PECL stats >= 1.0.0)
stats_dens_t — Probability density function of the t-distribution
Returns the probability density at x, where the
random variable follows the t-distribution of which the degree of
freedom is dfr.
xThe value at which the probability density is calculated
dfrThe degree of freedom of the distribution
The probability density at x or false for failure.