Histogram exclude zero

Hoink · March 2, 2007, 8:15am

Hello Rooters,

I am trying to draw the contents of a TNtupleD with a condition. When the condition is false (the point beeing 0 then), then the line should go through the next point not going through the point at 0.

As I understand the Drawing Option:
“P” : Draw current marker at each bin except empty bins
will do that for the markers.
Is there a similar way to also exlude these points also for the drawn line?

The code I am using is the following:

WithNoise->Draw("Height>>h11(360,20,200)","ErrorCoM*(ErrorCoM < 0.25)","c"); TH1D* h11 = (TH1D*)gDirectory->Get("h11"); h11->SetTitle("");
As you can see in the attached picture, the line goes down to zero when the condition is false. How can I avoid that and instead make the line go through the next point where the condition is true again?

Thank you,
Lutz

couet · March 2, 2007, 9:31am

Here is a possible way to get a continuous graph from an histogram having bins with zero contanet.

{
   Int_t nb = hpx->GetNbinsX();
   Double_t x,y;
   TGraph *g = new TGraph();
   Int_t ig=0;
   for (Int_t i=1; i<=100; i++) {
      y = hpx->GetBinContent(i);
      x = hpx->GetXaxis()->GetBinCenter(i);
      if (y>0) {
         g->SetPoint(ig,x,y);
         ig++;
      }
   }
   TCanvas c;
   c->Divide(1,2);
   c->cd(1); hpx->Draw();
   c->cd(2); g->Draw("al*");
}