pub fn digamma(x: Var<'_>) -> Var<'_>Expand description
Calculates the digamma function, which is the logarithmic derivative of the gamma function. It obeys the equation `digamma(x+1) = digamma(x)
- 1/x`. The approximation works better for large values. If the value is small, this function will shift it up using the digamma recurrence relation.