# illustrates how to exclude a range of bins from a fit

    // example to illustrate how to fit excluding points in a given range
    // Author: Rene Brun
    #include "TH1.h"
    #include "TF1.h"
    Double_t fline(Double_t *x, Double_t *par)
    {
        if (x[0] > 2.5 && x[0] < 3.5) {
          TF1::RejectPoint();
          return 0;
       }
       return par[0] + par[1]*x[0];
    }

    void fitExclude() {
       //Create a source function
       TF1 *f1 = new TF1("f1","[0] +[1]*x +gaus(2)",0,5);
       f1->SetParameters(6,-1,5,3,0.2);
       // create an histogram and fill it according to the source function
       TH1F *h = new TH1F("h","background + signal",100,0,5);
       h->FillRandom("f1",2000);
       TF1 *fline = new TF1("fline",fline,0,5,2);
       fline->SetParameters(2,-1);
       //we want to fit only the linear background excluding the signal area
       h->Fit("fline","l");
    }