Stairs graph from text file

ROOT
1

Hello,
I want to plot a stairs or step graph from the 2 column text file.
I am not able to find Draw option for stairs graph.
The simple program that I am using is :slightly_smiling_face:

FILE *fpm = fopen("Mass_Energy.txt", "r");

   int i=0;
   double a,b;

   TGraph *ab = new TGraph();

   while (fscanf(fpm, "%lf\t%lf", &a, &b)!=EOF) {
      i++;
      ab->SetPoint(i,a,b);
   }
   ab->SetMarkerStyle(21);   //21 for solid square, 20 for solid circle
   ab->Draw("P");

Hopefully, I need to make some changes to the Draw option.

ROOT Version: 6.14/04
Platform: Ubuntu 18.04 LTS

2

It seems you are looking for an historgam not a graph.
If you really need a graph you will have to insert the extra points making the stair and draw with option L.