Print fit result on TCanvas

[Svyatoslav]

Hello, I fit histogram and want to print result values on TCanvas.

Fit:

TFitResultPtr res_fit_mD = mass_D->Fit(f_total, "RSNQ");

Draw:

make_grid(his_Dp[i]);
DrwFun(list_fun[i]);

where:

void make_grid(TH1* his){
  gStyle->SetOptStat(10);
  gStyle->SetOptFit(112);
  gPad->SetGrid();
  his->SetMinimum(0);
}

void DrwFun(vector<TF1*> list_of_function){
  list_of_function.at(0)->SetLineColor(kRed);
  list_of_function.at(1)->SetLineColor(kGreen+2);
  list_of_function.at(2)->SetLineColor(kGray+2);
  
  list_of_function.at(0)->Draw("same");
  list_of_function.at(1)->Draw("same");
  list_of_function.at(2)->Draw("same");
}

Result:

I don’t see the result values of fit under “Entries 906198”. How to do this?

---

Please read tips for efficient and successful posting and posting code

ROOT Version: 6.26/06
Platform: Ubuntu
Compiler: Not Provided

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[bellenot]

@couet can hep you with that

[couet]

What do you see when you use the default setting:

gStyle->SetOptFit(1);

?

[couet]

With this simple example it is fine:

{
   auto h1 = new TH1F("h1","h1",200,-10,10);
   for (int i=0;i<=10000;i++) h1->Fill(gRandom->Gaus(0,1));
   gStyle -> SetOptFit(112);
   h1->Fit("gaus");
}

[Svyatoslav]

No changes

[couet]

So, can you provide a reproducer we ca run ?
As you see the simple example I posted is working.
There must be something special in your case.

[Svyatoslav]

When I delete N option from TFitResultPtr res_fit_mD = mass_D->Fit(f_total, "RSNQ"); root build two histograms:

I think the problem connect N option in Fit(). I make this option because I don’t wont to print first auto Draw.

I can give you all code (it’s big) and data. Next message.

[Svyatoslav]

Sorry, file with data too big. Code files. build_his.C is main.
build_his.C (14.7 KB)
Data_D0.C (1.4 KB)
Data_D0.h (5.7 KB)
Data_Dp.C (1.4 KB)
Data_Dp.h (6.7 KB)

[couet]

I cannot run your macro. I get: DTag_4180.root does not exist
May be try 0 instead of N.

[Svyatoslav]

File “DTag_4180.root” more 3 MB. How can I upload it?

[couet]

yes, try …

[couet]

what about option 0 ?

[Svyatoslav]

Yes, then I change 0 for N the problem is disappear. But new problem is born. The window with parameters is too small.

[couet]

It looks like you are fixing the box size somewhere . When it is fixed by the user it uses
that size. The automatic size occurs only if you let it free.

[Svyatoslav]

What if I don’t do it anywhere? This box size is created when I enter gStyle->SetOptStat(10);. And after size the box size is saved?

[Svyatoslav]

If I swap gStyle->SetOptFit(1); and gStyle->SetOptStat(10); then I get this