In this section: http://root.cern.ch/root/html/TH1.html#TH1:Fit@1 if you scroll to the section “Setting initial conditions”, there is this text:
[quote]For example, if you fit a function with 6 parameters, you can do:
func->SetParameters(0, 3.1, 1.e-6, -8, 0, 100);
func->SetParLimits(3, -10, -4);
func->FixParameter(4, 0);
func->SetParLimits(5, 1, 1);
With this setup, parameters 0->2 can vary freely
Parameter 3 has boundaries [-10,-4] with initial value -8
Parameter 4 is fixed to 0
Parameter 5 is fixed to 100.[/quote]
I do not understand why parameter 5 would be fixed to 100. It should be fixed to 1, or in the example command the call should be SetParLimits(5,100,100);.
Jean-François