hist011_TH1_legend_autoplaced.C File Reference

Detailed Description

The legend can be placed automatically in the current pad in an empty space found at painting time.

The following example illustrate this facility. Only the width and height of the legend is specified in percentage of the pad size.

 
void hist011_TH1_legend_autoplaced()
{
   auto *c4 = new TCanvas("c", "c", 600, 500);
 
   // Create a dummy histogram
   auto *hpx = new TH1D("hpx", "This is the hpx distribution", 100, -4., 4.);
   hpx->FillRandom("gaus", 50000);
   hpx->Draw("E");
   hpx->GetYaxis()->SetTitle("Y Axis title");
   hpx->GetYaxis()->SetTitleOffset(1.3);
   hpx->GetYaxis()->CenterTitle(true);
   hpx->GetXaxis()->SetTitle("X Axis title");
   hpx->GetXaxis()->CenterTitle(true);
 
   // Create another dummy histogram
   auto *h1 = new TH1D("h1", "A green histogram", 100, -2., 2.);
   h1->FillRandom("gaus", 10000);
   h1->SetLineColor(kGreen);
   h1->Draw("same");
 
   // Create a dummy graph
   auto *g = new TGraph();
   g->SetPoint(0, -3.5, 100);
   g->SetPoint(1, -3.0, 300);
   g->SetPoint(2, -2.0, 1000);
   g->SetPoint(3, 1.0, 800);
   g->SetPoint(4, 0.0, 200);
   g->SetPoint(5, 3.0, 200);
   g->SetPoint(6, 3.0, 700);
   g->Draw("L");
   g->SetTitle("This is a TGraph");
   g->SetLineColor(kRed);
   g->SetFillColor(0);
 
   // TPad::BuildLegend() default placement values are such that they trigger
   // the automatic placement.
   c4->BuildLegend();
}

Date

November 2024

Author

Olivier Couet

Definition in file hist011_TH1_legend_autoplaced.C.