Example macro showing some major probability density functions in ROOT. 
The macro shows four of them with respect to their two variables. In order to run the macro type:
Original tutorial by Andras Zsenei. 
  
import ROOT
 
 
f1a = 
ROOT.TF2(
"f1a",
"ROOT::Math::cauchy_pdf(x, y)",0,10,0,10)
 
f2a = 
ROOT.TF2(
"f2a",
"ROOT::Math::chisquared_pdf(x,y)",0,20, 0,20)
 
f3a = 
ROOT.TF2(
"f3a",
"ROOT::Math::gaussian_pdf(x,y)",0,10,0,5)
 
f4a = 
ROOT.TF2(
"f4a",
"ROOT::Math::tdistribution_pdf(x,y)",0,10,0,5)
 
 
ROOT::Detail::TRangeCast< T, true > TRangeDynCast
TRangeDynCast is an adapter class that allows the typed iteration through a TCollection.
 
- Author
 - Alberto Ferro 
 
Definition in file pdf002_2d_pdf.py.