Passing non-parameter variables to MINUIT2 FCn


Is it possible to pass two vectors to FCN in MINUIT2? I mean operator()(vector params, vecotr non-fitted-params)
At the moment they are all squeezed in to params and kept constant by upar interaction but I am not sure this is a good idea.



Why do you want to pass two vectors ? The FCN function is called by minuit to evaluate for different parameters the function value. Since it is a C++ interface you can customise for extra parameters as you like by making them data member of your FCN class and pass them by defining extra methods or using the FCN class constructor.

Best Regards



Thanks I am not even sure why I didn’t think of that earlier. Thanks for the tip that is exactly what I am going to do!