Show fitted function works differently (?) than before

Newbie
1

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ROOT Version: 5.34/36
Platform: cygwin
Compiler: 10.2.0

Hi, I have a funny problem, see this example:

TH1F* h1 = new TH1F("h1","h1",10,0.,1.);
h1->Fill(0.3)
h1->Fill(0.3)
h1->Fill(0.4)
h1->Fill(0.4)
h1->Fill(0.4)
h1->Fill(0.5)
h1->Fill(0.5)
h1->Fill(0.5)
h1->Fill(0.5) // etc.....
  TF1* gauss = new TF1("gFun","gaus");
  gauss->SetParNames("height","mean","sigma");
  gauss->SetLineColor(kRed);
  gauss->SetLineWidth(2);
 double gauPeak = h1->GetMaximum();
 gauss->SetParameters(10.,gauPeak,0.001);
TFitResultPtr res = h1->Fit("gFun","QS0"); // do NOT plot this just now
....... h1 is done, do other things, big code parts.....
h1->Draw();           //this does NOT plot the red gaussian!
h1->Draw("FUNC") //this does NOT plot anything. note there is a stat box

I thought (I am even 99% sure that I have used this behaviour before) that using option “0” to the fit means “do the fit, but do not mess with my pads & windows just_now” ; but it appears that it means instead “do not ever plot this curve” even if the associated curve exists.
Could you please clarify me this?
Thank you!

2

See “Warning when using the option "0"” in the TH1::Fit method description.

3

OK, thank you. Just 2 things, for my peace of spirit:

  1. has it always been like this?
  2. in the TH1::Fit doc (that today I have read and reread a dozen of times)
    the warning you mention should be really just below the place where the option “0” is mentioned, not 2 pages below, where nobody looks for it anymore.
    Bye, Sandro
4

This is like that at least since ROOT version 5.24 ie: June 2009