Dear rooters,

I’m struggling with the “GetChisquare” method when using the Levenberg-Marquardth Algorithm for the minimization when I limit a parameter within an certain interval with “SetParLimits”.

Although the fitted curve looks quite nice when plotted, the Chi-square is way to big when compared with TMinuitMinimizer. I’ve realized that without the “SetParLimits” everything looks normal, however I’m fitting a lot of spectra with a given function and I need to limit one of the function parameters, otherwise for some spectra the fit does not converge.

Does anyone knows what may be the reason?

Thank you in advance,

Jorge Machado