doc/hackathon/hist037__TH2Poly__boxes_8C.html

void hist037_TH2Poly_boxes()

{

   TCanvas *ch2p2 = new TCanvas("ch2p2", "ch2p2", 600, 400);

   gStyle->SetPalette(57);

   TH2Poly *h2p = new TH2Poly();

   h2p->SetName("Boxes");

   h2p->SetTitle("Boxes");


   Int_t i, j;

   Int_t nx = 40;

   Int_t ny = 40;

   Double_t xval1, yval1, xval2, yval2;

   Double_t dx = 0.2, dy = 0.1;

   xval1 = 0.;

   xval2 = dx;


   for (i = 0; i < nx; i++) {

      yval1 = 0.;

      yval2 = dy;

      for (j = 0; j < ny; j++) {

         h2p->AddBin(xval1, yval1, xval2, yval2);

         yval1 = yval2;

         yval2 = yval2 + yval2 * dy;

      }

      xval1 = xval2;

      xval2 = xval2 + xval2 * dx;

   }


   TRandom ran;

   for (i = 0; i < 300000; i++) {

      h2p->Fill(50 * ran.Gaus(2., 1), ran.Gaus(2., 1));

   }


   h2p->Draw("COLZ");

}

Int_t
int Int_t
Signed integer 4 bytes (int).
Definition RtypesCore.h:59

Double_t
double Double_t
Double 8 bytes.
Definition RtypesCore.h:73

gStyle
externTStyle * gStyle
Definition TStyle.h:442

TCanvas
The Canvas class.
Definition TCanvas.h:23

TH1::SetTitle
void SetTitle(const char *title) override
Change/set the title.
Definition TH1.cxx:6836

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

TH2Poly
2D Histogram with Polygonal Bins
Definition TH2Poly.h:66

TH2Poly::Fill
Int_t Fill(Double_t x, Double_t y) override
Increment the bin containing (x,y) by 1.
Definition TH2Poly.cxx:650

TH2Poly::AddBin
virtual Int_t AddBin(TObject *poly)
Adds a new bin to the histogram.
Definition TH2Poly.cxx:296

TRandom
This is the base class for the ROOT Random number generators.
Definition TRandom.h:27

TRandom::Gaus
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