Returns the probability density at x.
The density is zero for negative values. At zero it depends on the numerator degrees of freedom: it is infinite when the numerator df is less than 2, exactly 1.0 when equal to 2, and zero when greater than 2. For positive values the density is computed via exponentiation of the log-density.
Return
the probability density at x. Always non-negative.
Parameters
x
the point at which to evaluate the density.