Logo ROOT   6.14/05
Reference Guide
RooLandau.cxx
Go to the documentation of this file.
1 /*****************************************************************************
2  * Project: RooFit *
3  * Package: RooFitModels *
4  * @(#)root/roofit:$Id$
5  * Authors: *
6  * WV, Wouter Verkerke, UC Santa Barbara, verkerke@slac.stanford.edu *
7  * DK, David Kirkby, UC Irvine, dkirkby@uci.edu *
8  * *
9  * Copyright (c) 2000-2005, Regents of the University of California *
10  * and Stanford University. All rights reserved. *
11  * *
12  * Redistribution and use in source and binary forms, *
13  * with or without modification, are permitted according to the terms *
14  * listed in LICENSE (http://roofit.sourceforge.net/license.txt) *
15  *****************************************************************************/
16 
17 /** \class RooLandau
18  \ingroup Roofit
19 
20 Landau Distribution p.d.f
21 **/
22 
23 #include "TMath.h"
24 #include "RooFit.h"
25 
26 #include "RooLandau.h"
27 #include "RooLandau.h"
28 #include "RooRandom.h"
29 
30 #include "TError.h"
31 
32 using namespace std;
33 
35 
36 ////////////////////////////////////////////////////////////////////////////////
37 
38 RooLandau::RooLandau(const char *name, const char *title, RooAbsReal& _x, RooAbsReal& _mean, RooAbsReal& _sigma) :
39  RooAbsPdf(name,title),
40  x("x","Dependent",this,_x),
41  mean("mean","Mean",this,_mean),
42  sigma("sigma","Width",this,_sigma)
43 {
44 }
45 
46 ////////////////////////////////////////////////////////////////////////////////
47 
48 RooLandau::RooLandau(const RooLandau& other, const char* name) :
49  RooAbsPdf(other,name),
50  x("x",this,other.x),
51  mean("mean",this,other.mean),
52  sigma("sigma",this,other.sigma)
53 {
54 }
55 
56 ////////////////////////////////////////////////////////////////////////////////
57 
59 {
60  return TMath::Landau(x, mean, sigma);
61 }
62 
63 ////////////////////////////////////////////////////////////////////////////////
64 
65 Int_t RooLandau::getGenerator(const RooArgSet& directVars, RooArgSet &generateVars, Bool_t /*staticInitOK*/) const
66 {
67  if (matchArgs(directVars,generateVars,x)) return 1 ;
68  return 0 ;
69 }
70 
71 ////////////////////////////////////////////////////////////////////////////////
72 
74 {
75  R__ASSERT(code==1) ;
76  Double_t xgen ;
77  while(1) {
79  if (xgen<x.max() && xgen>x.min()) {
80  x = xgen ;
81  break;
82  }
83  }
84  return;
85 }
Double_t Landau(Double_t x, Double_t mpv=0, Double_t sigma=1, Bool_t norm=kFALSE)
The LANDAU function.
Definition: TMath.cxx:469
Bool_t matchArgs(const RooArgSet &allDeps, RooArgSet &numDeps, const RooArgProxy &a) const
Utility function for use in getAnalyticalIntegral().
RooLandau()
Definition: RooLandau.h:26
#define R__ASSERT(e)
Definition: TError.h:96
int Int_t
Definition: RtypesCore.h:41
bool Bool_t
Definition: RtypesCore.h:59
STL namespace.
Landau Distribution p.d.f.
Definition: RooLandau.h:24
Double_t evaluate() const
Definition: RooLandau.cxx:58
RooRealProxy mean
Definition: RooLandau.h:38
Double_t x[n]
Definition: legend1.C:17
Int_t getGenerator(const RooArgSet &directVars, RooArgSet &generateVars, Bool_t staticInitOK=kTRUE) const
Load generatedVars with the subset of directVars that we can generate events for, and return a code t...
Definition: RooLandau.cxx:65
void generateEvent(Int_t code)
Interface for generation of anan event using the algorithm corresponding to the specified code...
Definition: RooLandau.cxx:73
static TRandom * randomGenerator()
Return a pointer to a singleton random-number generator implementation.
Definition: RooRandom.cxx:54
const Double_t sigma
RooRealProxy x
Definition: RooLandau.h:37
#define ClassImp(name)
Definition: Rtypes.h:359
Double_t min(const char *rname=0) const
Definition: RooRealProxy.h:56
double Double_t
Definition: RtypesCore.h:55
RooAbsReal is the common abstract base class for objects that represent a real value and implements f...
Definition: RooAbsReal.h:53
Double_t max(const char *rname=0) const
Definition: RooRealProxy.h:57
RooAbsPdf is the abstract interface for all probability density functions The class provides hybrid a...
Definition: RooAbsPdf.h:41
virtual Double_t Landau(Double_t mean=0, Double_t sigma=1)
Generate a random number following a Landau distribution with location parameter mu and scale paramet...
Definition: TRandom.cxx:361
char name[80]
Definition: TGX11.cxx:109
RooRealProxy sigma
Definition: RooLandau.h:39