[#0] WARNING:InputArguments -- The parameter 'x' with range [0, 50] of the RooChiSquarePdf 'cs' exceeds the safe range of (0, inf). Advise to limit its range.
[#0] WARNING:InputArguments -- The parameter 'k' with range [0, 5] of the RooChiSquarePdf 'cs' exceeds the safe range of (0, inf). Advise to limit its range.
[#1] INFO:InputArguments -- RooNonCentralChiSquare sum being forced
[#0] WARNING:Eval -- RooNonCentralChiSquare did not converge: for x=36 k=2.01, lambda=5 fractional error = 0.00108172
 either adjust tolerance with SetErrorTolerance(tol) or max_iter with SetMaxIter(max_it)