Suppose I am fitting a histogrma by a function of three variables: A, B, C. Setting limits on one one parameters is quite simple: using SetParLimits.
I need to know how to do it for a combination of these paramters, i.e. set a constraint. For example set the parameter limit on “A*B”.
I can do some coding trick, but I am not sure if we can do it with root facilities. Ahmed