16    auto c1 = 
new TCanvas(
"c1", 
"fit residual simple");
    17    auto h1 = 
new TH1D(
"h1", 
"h1", 50, -5, 5);
    24    std::vector<double> lines = {-3, -2, -1, 0, 1, 2, 3};
    25    rp1->SetGridlines(lines);
    27    rp1->GetLowerRefGraph()->SetMinimum(-4);
    28    rp1->GetLowerRefGraph()->SetMaximum(4);
 
R__EXTERN TStyle * gStyle
virtual void FillRandom(const char *fname, Int_t ntimes=5000)
Fill histogram following distribution in function fname. 
void SetOptStat(Int_t stat=1)
The type of information printed in the histogram statistics box can be selected via the parameter mod...
THist< 1, double, THistStatContent, THistStatUncertainty > TH1D
Class for displaying ratios, differences and fit residuals. 
virtual void SetTitle(const char *title="")
Set the title of the TNamed. 
virtual TFitResultPtr Fit(const char *formula, Option_t *option="", Option_t *goption="", Double_t xmin=0, Double_t xmax=0)
Fit histogram with function fname.