The good old X-axis range problem

[Wile_E_Coyote]

Setting Axis Range Exactly With Variable Bins

You could create and draw an empty histogram, with sufficiently dense x-bins. And then, on top of it, you could draw your “hist” using “same”: { Double_t x[] = {0., 100., 150., 200., 500., 20000.}; TH1F *hist = new TH1F("hist", "hist title;x axis name;y axis name", ((sizeof(x) / sizeof(Double_t)) - 1), x); hist->SetLineColor(kRed); hist->Fill(0., 1.); hist->Fill(100., 2.); hist->Fill(150., 3.); hist->Fill(200., 4.); hist->Fill(500., 5.); // TH1C *h = new TH1C…