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1/// \file
2/// \ingroup tutorial_hist
4/// This tutorial demonstrates how the highlight mechanism can be used on an histogram.
5/// A 2D histogram is booked an filled with a random gaussian distribution.
6/// Then an highlight method is connected to the histogram. Moving the mouse
7/// on the histogram will update the histogram title in real time according to
8/// the highlighted bin.
10/// \macro_code
12/// \date March 2018
13/// \author Jan Musinsky
15TText *info = nullptr;
17void HighlightTitle(TVirtualPad *pad, TObject *obj, Int_t xhb, Int_t yhb)
19 auto h2 = dynamic_cast<TH2F*>(obj);
20 if (!h2) return;
21 if (!h2->IsHighlight()) { // after highlight disabled
22 h2->SetTitle("Disable highlight");
23 return;
24 }
25 if (info) info->SetTitle("");
26 TString t;
27 t.Form("bin[%02d, %02d] (%5.2f, %5.2f) content %g", xhb, yhb,
28 h2->GetXaxis()->GetBinCenter(xhb), h2->GetYaxis()->GetBinCenter(yhb),
29 h2->GetBinContent(xhb, yhb));
30 h2->SetTitle(t.Data());
31 pad->Update();
34void hlHisto1()
36 auto c1 = new TCanvas();
37 c1->HighlightConnect("HighlightTitle(TVirtualPad*,TObject*,Int_t,Int_t)");
39 auto h2 = new TH2F("h2", "", 50, -5.0, 5.0, 50, -5.0, 5.0);
40 for (Int_t i = 0; i < 10000; i++) h2->Fill(gRandom->Gaus(), gRandom->Gaus());
41 h2->Draw();
43 info = new TText(0.0, -4.0, "please move the mouse over the frame");
44 info->SetTextAlign(22);
45 info->SetTextColor(kRed+1);
46 info->SetBit(kCannotPick);
47 info->Draw();
48 c1->Update();
50 // call after update to apply changes in the histogram painter
51 h2->SetHighlight();
int Int_t
Definition: RtypesCore.h:45
@ kRed
Definition: Rtypes.h:66
@ kCannotPick
Definition: TObject.h:374
R__EXTERN TRandom * gRandom
Definition: TRandom.h:62
virtual void SetTextAlign(Short_t align=11)
Set the text alignment.
Definition: TAttText.h:42
virtual void SetTextColor(Color_t tcolor=1)
Set the text color.
Definition: TAttText.h:44
The Canvas class.
Definition: TCanvas.h:23
void SetTitle(const char *title) override
Change (i.e.
Definition: TH1.cxx:6700
2-D histogram with a float per channel (see TH1 documentation)}
Definition: TH2.h:257
virtual void SetTitle(const char *title="")
Set the title of the TNamed.
Definition: TNamed.cxx:164
Mother of all ROOT objects.
Definition: TObject.h:41
void SetBit(UInt_t f, Bool_t set)
Set or unset the user status bits as specified in f.
Definition: TObject.cxx:775
virtual void Draw(Option_t *option="")
Default Draw method for all objects.
Definition: TObject.cxx:274
virtual Double_t Gaus(Double_t mean=0, Double_t sigma=1)
Samples a random number from the standard Normal (Gaussian) Distribution with the given mean and sigm...
Definition: TRandom.cxx:274
Basic string class.
Definition: TString.h:136
const char * Data() const
Definition: TString.h:369
void Form(const char *fmt,...)
Formats a string using a printf style format descriptor.
Definition: TString.cxx:2323
Base class for several text objects.
Definition: TText.h:22
TVirtualPad is an abstract base class for the Pad and Canvas classes.
Definition: TVirtualPad.h:51
virtual void Update()=0
return c1
Definition: legend1.C:41