RooFit normalization

Dear experts,

I see normalization is called only one time for each minuit step, and it’s called for the first event after evaluate(). Can somebody point me RooFit use which class to manage this logic? Basically I would like to know which class RooFit uses to check if normalization should be called.

If I know this, I can cache some internal parameters when the first event calls evaluate().

Liming Zhang


The way RooFit handles the normalisation is rather complex and depends on the case. Basically the integral of the pdf are computed only when needed, for example when the parameters changes. I don’t think there is a single class to control this. However for this low-level questions about RooFit, I suggest you to contact directly the RooFit author

Best Regards