doc/hackathon/hist017__TH1__smooth_8C.html

int ipad = 1;

TCanvas *c1 = 0;


void smooth_hist(const char *fname, double xmin, double xmax, int n1, int n2)

{


   std::cout << "smoothing a " << fname << " histogram" << std::endl;


   TH1D *h1 = new TH1D("h1", "h1", 100, xmin, xmax);

   TH1D *h2 = new TH1D("h2", "h2", 100, xmin, xmax);

   h1->FillRandom(fname, n1);


   TH1D *h1_s = new TH1D(*h1);

   h1_s->SetName("h1_s");

   h1_s->Smooth();


   h2->FillRandom(fname, n2);


   double p1 = h1->Chi2Test(h2, "");

   double p2 = h1_s->Chi2Test(h2, "UU");

   if (p2 < p1)

      Error("testSmooth", "TH1::Smooth is not working correctly - a worst chi2 is obtained");


   std::cout << " chi2 test non-smoothed histo " << p1 << std::endl;

   std::cout << " chi2 test smoothed histo     " << p2 << std::endl;


   double a1 = h1->AndersonDarlingTest(h2);

   double a2 = h1_s->AndersonDarlingTest(h2);


   std::cout << " AD test non-smoothed histo " << a1 << std::endl;

   std::cout << " AD test smoothed histo     " << a2 << std::endl;


   double k1 = h1->KolmogorovTest(h2);

   double k2 = h1_s->KolmogorovTest(h2);


   std::cout << " KS test non-smoothed histo " << k1 << std::endl;

   std::cout << " KS test smoothed histo     " << k2 << std::endl;


   c1->cd(ipad++);

   h1->Draw("E");

   h1_s->SetLineColor(kRed);

   h1_s->Draw("same");

   h2->Scale(double(n1) / n2);

   h2->SetLineColor(kGreen);

   h2->Draw("same");

}


void hist017_TH1_smooth(int n1 = 1000, int n2 = 1000000)

{


   TDirectory::TContext ctx{nullptr}; // Don't register histograms to the current directory


   c1 = new TCanvas();

   c1->Divide(1, 3);


   smooth_hist("gaus", -5, 5, n1, n2);

   smooth_hist("landau", -5, 15, n1, n2);

   smooth_hist("expo", -5, 0, n1, n2);

}

kRed
@ kRed
Definition Rtypes.h:67

kGreen
@ kGreen
Definition Rtypes.h:67

Error
Error("WriteTObject","The current directory (%s) is not associated with a file. The object (%s) has not been written.", GetName(), objname)

xmin
float xmin
Definition THbookFile.cxx:95

xmax
float xmax
Definition THbookFile.cxx:95

TAttLine::SetLineColor
virtual void SetLineColor(Color_t lcolor)
Set the line color.
Definition TAttLine.h:44

TCanvas
The Canvas class.
Definition TCanvas.h:23

TDirectory::TContext
TDirectory::TContext keeps track and restore the current directory.
Definition TDirectory.h:89

TH1D
1-D histogram with a double per channel (see TH1 documentation)
Definition TH1.h:926

TH1::Smooth
virtual void Smooth(Int_t ntimes=1, Option_t *option="")
Smooth bin contents of this histogram.
Definition TH1.cxx:7004

TH1::FillRandom
virtual void FillRandom(TF1 *f1, Int_t ntimes=5000, TRandom *rng=nullptr)
Definition TH1.cxx:3577

TH1::Draw
void Draw(Option_t *option="") override
Draw this histogram with options.
Definition TH1.cxx:3097

TH1::SetName
void SetName(const char *name) override
Change the name of this histogram.
Definition TH1.cxx:9097

TH1::AndersonDarlingTest
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:8195

TH1::Chi2Test
virtual Double_t Chi2Test(const TH1 *h2, Option_t *option="UU", Double_t *res=nullptr) const
test for comparing weighted and unweighted histograms.
Definition TH1.cxx:2025

TH1::Scale
virtual void Scale(Double_t c1=1, Option_t *option="")
Multiply this histogram by a constant c1.
Definition TH1.cxx:6719

TH1::KolmogorovTest
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:8311

c1
return c1
Definition legend1.C:41

h1
TH1F * h1
Definition legend1.C:5