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Reference Guide
testSmooth.C
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1/// \file
2/// \ingroup tutorial_hist
3/// \notebook
4/// Histogram smoothing.
5///
6/// \macro_image
7/// \macro_code
8///
9/// \author Rene Brun
10
11int ipad = 1;
12TCanvas * c1 = 0;
13
14void smooth_hist(const char * fname, double xmin, double xmax, int n1, int n2) {
15
16 std::cout << "smoothing a " << fname << " histogram" << std::endl;
17
18 TH1D * h1 = new TH1D("h1","h1",100,xmin,xmax);
19 TH1D * h2 = new TH1D("h2","h2",100,xmin,xmax);
20 h1->FillRandom(fname,n1);
21
22 TH1D * h1_s = new TH1D(*h1);
23 h1_s->SetName("h1_s");
24 h1_s->Smooth();
25
26 h2->FillRandom(fname,n2);
27
28 double p1 = h1->Chi2Test(h2,"");
29 double p2 = h1_s->Chi2Test(h2,"UU");
30 if (p2 < p1) Error("testSmooth","TH1::Smooth is not working correctly - a worst chi2 is obtained");
31
32 std::cout << " chi2 test non-smoothed histo " << p1 << std::endl;
33 std::cout << " chi2 test smoothed histo " << p2 << std::endl;
34
35 double a1 = h1->AndersonDarlingTest(h2);
36 double a2 = h1_s->AndersonDarlingTest(h2);
37
38 std::cout << " AD test non-smoothed histo " << a1 << std::endl;
39 std::cout << " AD test smoothed histo " << a2 << std::endl;
40
41 double k1 = h1->KolmogorovTest(h2);
42 double k2 = h1_s->KolmogorovTest(h2);
43
44 std::cout << " KS test non-smoothed histo " << k1 << std::endl;
45 std::cout << " KS test smoothed histo " << k2 << std::endl;
46
47 c1->cd(ipad++);
48 h1->Draw("E");
49 h1_s->SetLineColor(kRed);
50 h1_s->Draw("same");
51 h2->Scale(double(n1)/n2);
53 h2->Draw("same");
54}
55
56void testSmooth(int n1 = 1000, int n2 = 1000000) {
57
58 TH1::AddDirectory(false);
59
60 c1 = new TCanvas();
61 c1->Divide(1,3);
62
63
64 smooth_hist("gaus",-5,5,n1,n2);
65 smooth_hist("landau",-5,15,n1,n2);
66 smooth_hist("expo",-5,0,n1,n2);
67
68}
@ kRed
Definition: Rtypes.h:66
@ kGreen
Definition: Rtypes.h:66
void Error(const char *location, const char *msgfmt,...)
Use this function in case an error occurred.
Definition: TError.cxx:187
float xmin
Definition: THbookFile.cxx:95
float xmax
Definition: THbookFile.cxx:95
virtual void SetLineColor(Color_t lcolor)
Set the line color.
Definition: TAttLine.h:40
The Canvas class.
Definition: TCanvas.h:23
1-D histogram with a double per channel (see TH1 documentation)}
Definition: TH1.h:617
virtual void Smooth(Int_t ntimes=1, Option_t *option="")
Smooth bin contents of this histogram.
Definition: TH1.cxx:6875
static void AddDirectory(Bool_t add=kTRUE)
Sets the flag controlling the automatic add of histograms in memory.
Definition: TH1.cxx:1277
virtual void FillRandom(const char *fname, Int_t ntimes=5000, TRandom *rng=nullptr)
Fill histogram following distribution in function fname.
Definition: TH1.cxx:3523
virtual Double_t Chi2Test(const TH1 *h2, Option_t *option="UU", Double_t *res=0) const
test for comparing weighted and unweighted histograms
Definition: TH1.cxx:2002
void Draw(Option_t *option="") override
Draw this histogram with options.
Definition: TH1.cxx:3070
void SetName(const char *name) override
Change the name of this histogram.
Definition: TH1.cxx:8835
virtual Double_t AndersonDarlingTest(const TH1 *h2, Option_t *option="") const
Statistical test of compatibility in shape between this histogram and h2, using the Anderson-Darling ...
Definition: TH1.cxx:7981
virtual void Scale(Double_t c1=1, Option_t *option="")
Multiply this histogram by a constant c1.
Definition: TH1.cxx:6594
virtual Double_t KolmogorovTest(const TH1 *h2, Option_t *option="") const
Statistical test of compatibility in shape between this histogram and h2, using Kolmogorov test.
Definition: TH1.cxx:8095
return c1
Definition: legend1.C:41
TH1F * h1
Definition: legend1.C:5