SLB: Simplify XGBoost->TMVA cut transformation equation
I simplified the equation used to convert the (XGBoost cut)->(TMVA cut) conversion. The two functions are mathematically equivalent. Don't know if it makes sense to commit this to master or 2025-patches so please advise there.
Previous maths: t = \frac{2}{1+ e^{-2 \xi}} -1 where: \xi = -\log\left( \frac{1}{x} -1 \right). New maths:
t = \frac{2 x - 1}{2 x^2 - 2 x + 1}.
Edited by Andy Morris