Root paints outside the Frame

[Radek1]

In case of logaritmic x-axis root paints histogram outside the frame, see the following code.

   TH1::SetDefaultSumw2(true);
   TH1D *h1, *h2;

   h1 = new TH1D("h1", "", 20, 1, 30);
   h2 = new TH1D("h2", "", 20, 1, 30);

   for(int i = 0; i < 100000; ++i) {
      h1->Fill( 30*pow(gRandom->Gaus(),2) );
      h2->Fill( 40*pow(gRandom->Gaus(),2) );
   }
   TCanvas *can = new TCanvas("can");
   can->SetLeftMargin(0.4);
   h1->Draw();
   h1->SetMaximum(6000);
   h2->SetLineColor(kRed);
   h2->SetLineWidth(3);
   h2->Draw("same");
   gPad->SetLogx();

   h1->GetXaxis()->SetRangeUser(8.4, 30);

[couet]

A workaround is to apply the same range on h2:

{
   TH1::SetDefaultSumw2(true);
   TH1D *h1, *h2;

   h1 = new TH1D("h1", "", 20, 1, 30);
   h2 = new TH1D("h2", "", 20, 1, 30);

   for(int i = 0; i < 100000; ++i) {
      h1->Fill( 30*pow(gRandom->Gaus(),2) );
      h2->Fill( 40*pow(gRandom->Gaus(),2) );
   }

   TCanvas *can = new TCanvas("can");
   can->SetLeftMargin(0.4);

   h1->SetMaximum(6000);
   h1->Draw();
   h1->GetXaxis()->SetRangeUser(8.4, 30);
   gPad->SetLogx();

   h2->SetLineColor(kRed);
   h2->SetLineWidth(3);
   h2->Draw("same");
   h2->GetXaxis()->SetRangeUser(8.4, 30);
}

[Radek1]

Thanks,
It’s quite confusing to call SetRangeUser for every object drawn with “same” to prevent painting outside, but why not, it’s working.
I am just wondering why the same script with linear-axis works well, whereas log-axis has this peculiar feature. It is probably not by purpose.
Cheers
Radek

[couet]

I agree with you this is not the right behavior. I will have a look if something can be done.