TH1::Add extension proposal

I haven’t found any direct way to “shift” the histogram’s “bin contents” so I’d like to propose the following extensions:

// this = this + c1h1 + c2
void TH1::Add(const TH1
h1, Double_t c1 = 1, Double_t c2 = 0)

// this = c1h1 + c2h2 + c3
void Add(const TH1* h, const TH1* h2, Double_t c1 = 1, Double_t c2 = 1, Double_t c3 = 0)

These changes should be fully “backwards compatible”.

For shifting an histogram you can use TH1::Add passing a TF1 object built as a constant function.