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Reference Guide
FeldmanCousins.C
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1/// \file
2/// \ingroup tutorial_math
3/// \notebook -nodraw
4/// Example macro of using the TFeldmanCousins class in root.
5///
6/// get a FeldmanCousins calculation object with the default limits
7/// of calculating a 90% CL with the minimum signal value scanned
8/// = 0.0 and the maximum signal value scanned of 50.0
9///
10/// \macro_output
11/// \macro_code
12///
13/// \author Adrian John Bevan <bevan@SLAC.Stanford.EDU>
14
15void FeldmanCousins()
16{
17 if (!gROOT->GetClass("TFeldmanCousins"))
18 R__LOAD_LIBRARY(libPhysics);
19
21
22 // calculate either the upper or lower limit for 10 observed
23 // events with an estimated background of 3. The calculation of
24 // either upper or lower limit will return that limit and fill
25 // data members with both the upper and lower limit for you.
26 Double_t Nobserved = 10.0;
27 Double_t Nbackground = 3.0;
28
29 Double_t ul = f.CalculateUpperLimit(Nobserved, Nbackground);
30 Double_t ll = f.GetLowerLimit();
31
32 cout << "For " << Nobserved << " data observed with and estimated background"<<endl;
33 cout << "of " << Nbackground << " candidates, the Feldman-Cousins method of "<<endl;
34 cout << "calculating confidence limits gives:"<<endl;
35 cout << "\tUpper Limit = " << ul << endl;
36 cout << "\tLower Limit = " << ll << endl;
37 cout << "at the 90% CL"<< endl;
38}
39
#define f(i)
Definition: RSha256.hxx:104
double Double_t
Definition: RtypesCore.h:59
#define R__LOAD_LIBRARY(LIBRARY)
Definition: Rtypes.h:489
#define gROOT
Definition: TROOT.h:404
Class to calculate the CL upper limit using the Feldman-Cousins method as described in PRD V57 #7,...