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hsumTimer.C
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1/// \file
2/// \ingroup tutorial_hist
3/// \notebook -js
4/// Demo of Timers.
5///
6/// Simple example illustrating how to use the C++ interpreter
7/// to fill histograms in a loop and show the graphics results
8/// This program is a variant of the tutorial "hsum".
9/// It illustrates the use of Timers.
10///
11/// \macro_image
12/// \macro_code
13///
14/// \author Rene Brun
15
16Float_t progressRatio;
17TSlider *slider;
18TCanvas *c1;
19
20void hsumUpdate()
21{
22// called when Timer times out
23 if (slider) slider->SetRange(0, ::progressRatio);
24 c1->Modified();
25 c1->Update();
26}
27
28void hsumTimer(Int_t nfill=100000)
29{
30 c1 = new TCanvas("c1","The HSUM example",200,10,600,400);
31 c1->SetGrid();
32
33
34 // Create some histograms.
35 auto total = new TH1F("total","This is the total distribution",100,-4,4);
36 auto main = new TH1F("main","Main contributor",100,-4,4);
37 auto s1 = new TH1F("s1","This is the first signal",100,-4,4);
38 auto s2 = new TH1F("s2","This is the second signal",100,-4,4);
39 total->Sumw2(); // store the sum of squares of weights
40 total->SetMarkerStyle(21);
41 total->SetMarkerSize(0.7);
42 main->SetFillColor(16);
43 s1->SetFillColor(42);
44 s2->SetFillColor(46);
45 total->SetMaximum(nfill/20.);
46 total->Draw("e1p");
47 main->Draw("same");
48 s1->Draw("same");
49 s2->Draw("same");
50 c1->Update();slider = new TSlider("slider",
51 "test",4.2,0,4.6,0.8*total->GetMaximum(),38);
52 slider->SetFillColor(46);
53
54 // Create a TTimer (hsumUpdate called every 300 msec)
55 TTimer timer("hsumUpdate()",300);
56 timer.TurnOn();
57
58 // Fill histograms randomly
59 Float_t xs1, xs2, xmain;
61 for (Int_t i=0; i<nfill; i++) {
62 ::progressRatio = Float_t(i)/Float_t(nfill);
63 if (gSystem->ProcessEvents()) break;
64 xmain = gRandom->Gaus(-1,1.5);
65 xs1 = gRandom->Gaus(-0.5,0.5);
66 xs2 = gRandom->Landau(1,0.15);
67 main->Fill(xmain);
68 s1->Fill(xs1,0.3);
69 s2->Fill(xs2,0.2);
70 total->Fill(xmain);
71 total->Fill(xs1,0.3);
72 total->Fill(xs2,0.2);
73 }
74 timer.TurnOff();
75 hsumUpdate();
76}
77
#define s1(x)
Definition: RSha256.hxx:91
int Int_t
Definition: RtypesCore.h:45
float Float_t
Definition: RtypesCore.h:57
static unsigned int total
R__EXTERN TRandom * gRandom
Definition: TRandom.h:62
R__EXTERN TSystem * gSystem
Definition: TSystem.h:559
int main(int argc, char *argv[])
Definition: cef_main.cxx:54
virtual void SetFillColor(Color_t fcolor)
Set the fill area color.
Definition: TAttFill.h:37
The Canvas class.
Definition: TCanvas.h:23
1-D histogram with a float per channel (see TH1 documentation)}
Definition: TH1.h:574
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
virtual void SetSeed(ULong_t seed=0)
Set the random generator seed.
Definition: TRandom.cxx:608
virtual Double_t Landau(Double_t mean=0, Double_t sigma=1)
Generate a random number following a Landau distribution with location parameter mu and scale paramet...
Definition: TRandom.cxx:380
A specialized TPad including a TSliderBox object.
Definition: TSlider.h:17
virtual void SetRange(Double_t xmin=0, Double_t xmax=1)
Set Slider range in [0,1].
Definition: TSlider.cxx:207
virtual Bool_t ProcessEvents()
Process pending events (GUI, timers, sockets).
Definition: TSystem.cxx:419
Handles synchronous and a-synchronous timer events.
Definition: TTimer.h:51
return c1
Definition: legend1.C:41