Extrapolate fit

Hi

I would like to know, how it possible to extrapolate a fitted histogram –

For example, if the histo xaxis is 0->2.5 (eta) and you have values between 0.4 and 2.1 you can fit on this (fitpanel, whatever) --now, how can I extrapolate the results to 0 and 2.5 respectively? - Also, is it possible from Fitpanel?

TIA

Alexis

Get a pointer to the function and evaluate the function outside its range, eg

TF1 *f = (TF1*)myhist->GetFunction("functionname"); f->Eval(x); where x may be outside the range used to fit
Rene