Help needed on how iterating fitting and using minimizer

Roofit and RooStats
1

Dear all,

 I am trying to fit 2 peaks with overlapping tails and superimposed to a background.

I usually make a simple fit, but I read there are iterative methods using different minimizers (I am interested in Nelder Mead).

I have no idea of how using minimizers.
In attachment are my data and my code (basic fitting routine, with no minimizer).
Could anyone help me to make the final fit (fitFcn) to iterate x times up to when the reduced chisquare is minimized, pls?

Thanks,
Francesca
Output.dat (21 KB)
PlotSinglePeakMiniizer.C (6.18 KB)

2

Hi,

You can change the minimiser algorithm when fitting by simple doing:

ROOT::Math::MinimizerOptions::SetDefaultMinimizer("Minuit","Simplex");

But I am not sure that it will work better than Migrad

Lorenzo