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Reference Guide
TVector2.cxx
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1 // @(#)root/physics:$Id$
2 // Author: Pasha Murat 12/02/99
3 
4 /*************************************************************************
5  * Copyright (C) 1995-2000, Rene Brun and Fons Rademakers. *
6  * All rights reserved. *
7  * *
8  * For the licensing terms see $ROOTSYS/LICENSE. *
9  * For the list of contributors see $ROOTSYS/README/CREDITS. *
10  *************************************************************************/
11 
12 /** \class TVector2
13  \ingroup Physics
14 
15 TVector2 is a general two vector class, which can be used for
16 the description of different vectors in 2D.
17 */
18 
19 #include "TROOT.h"
20 #include "TVector2.h"
21 #include "TMath.h"
22 
24 Double_t const kTWOPI = 2.*kPI;
25 
27 
28 ////////////////////////////////////////////////////////////////////////////////
29 /// Constructor
30 
32 {
33  fX = 0.;
34  fY = 0.;
35 }
36 
37 ////////////////////////////////////////////////////////////////////////////////
38 /// Constructor
39 
41 {
42  fX = v[0];
43  fY = v[1];
44 }
45 
46 ////////////////////////////////////////////////////////////////////////////////
47 /// Constructor
48 
50 {
51  fX = x0;
52  fY = y0;
53 }
54 
55 ////////////////////////////////////////////////////////////////////////////////
56 
58 {
59 }
60 
61 ////////////////////////////////////////////////////////////////////////////////
62 /// Return modulo of this vector
63 
65 {
66  return TMath::Sqrt(fX*fX+fY*fY);
67 }
68 
69 ////////////////////////////////////////////////////////////////////////////////
70 /// Return module normalized to 1
71 
73 {
74  return (Mod2()) ? *this/Mod() : TVector2();
75 }
76 
77 ////////////////////////////////////////////////////////////////////////////////
78 /// Return vector phi
79 
81 {
82  return TMath::Pi()+TMath::ATan2(-fY,-fX);
83 }
84 
85 ////////////////////////////////////////////////////////////////////////////////
86 /// Returns phi angle in the interval [0,2*PI)
87 
89  if(TMath::IsNaN(x)){
90  gROOT->Error("TVector2::Phi_0_2pi","function called with NaN");
91  return x;
92  }
93  while (x >= kTWOPI) x -= kTWOPI;
94  while (x < 0.) x += kTWOPI;
95  return x;
96 }
97 
98 ////////////////////////////////////////////////////////////////////////////////
99 /// Returns phi angle in the interval [-PI,PI)
100 
102  if(TMath::IsNaN(x)){
103  gROOT->Error("TVector2::Phi_mpi_pi","function called with NaN");
104  return x;
105  }
106  while (x >= kPI) x -= kTWOPI;
107  while (x < -kPI) x += kTWOPI;
108  return x;
109 }
110 
111 ////////////////////////////////////////////////////////////////////////////////
112 /// Rotation by phi
113 
115 {
116  return TVector2( fX*TMath::Cos(phi)-fY*TMath::Sin(phi), fX*TMath::Sin(phi)+fY*TMath::Cos(phi) );
117 }
118 
119 ////////////////////////////////////////////////////////////////////////////////
120 /// Set vector using mag and phi
121 
123 {
124  Double_t amag = TMath::Abs(mag);
125  fX = amag * TMath::Cos(phi);
126  fY = amag * TMath::Sin(phi);
127 }
128 ////////////////////////////////////////////////////////////////////////////////
129 /// Stream an object of class TVector2.
130 
131 void TVector2::Streamer(TBuffer &R__b)
132 {
133  if (R__b.IsReading()) {
134  UInt_t R__s, R__c;
135  Version_t R__v = R__b.ReadVersion(&R__s, &R__c);
136  if (R__v > 2) {
137  R__b.ReadClassBuffer(TVector2::Class(), this, R__v, R__s, R__c);
138  return;
139  }
140  //====process old versions before automatic schema evolution
141  if (R__v < 2) TObject::Streamer(R__b);
142  R__b >> fX;
143  R__b >> fY;
144  R__b.CheckByteCount(R__s, R__c, TVector2::IsA());
145  //====end of old versions
146 
147  } else {
148  R__b.WriteClassBuffer(TVector2::Class(),this);
149  }
150 }
151 
153 {
154  //print vector parameters
155  Printf("%s %s (x,y)=(%f,%f) (rho,phi)=(%f,%f)",GetName(),GetTitle(),X(),Y(),
156  Mod(),Phi()*TMath::RadToDeg());
157 }
static Double_t Phi_0_2pi(Double_t x)
Returns phi angle in the interval [0,2*PI)
Definition: TVector2.cxx:88
Bool_t IsReading() const
Definition: TBuffer.h:85
Double_t fY
Definition: TVector2.h:25
virtual Int_t WriteClassBuffer(const TClass *cl, void *pointer)=0
short Version_t
Definition: RtypesCore.h:61
const char Option_t
Definition: RtypesCore.h:62
Double_t const kTWOPI
Definition: TVector2.cxx:24
Double_t fX
Definition: TVector2.h:24
Buffer base class used for serializing objects.
Definition: TBuffer.h:42
virtual Int_t CheckByteCount(UInt_t startpos, UInt_t bcnt, const TClass *clss)=0
#define gROOT
Definition: TROOT.h:415
TVector2 Rotate(Double_t phi) const
Rotation by phi.
Definition: TVector2.cxx:114
Bool_t IsNaN(Double_t x)
Definition: TMath.h:882
Short_t Abs(Short_t d)
Definition: TMathBase.h:120
TVector2 is a general two vector class, which can be used for the description of different vectors in...
Definition: TVector2.h:18
Double_t x[n]
Definition: legend1.C:17
void Class()
Definition: Class.C:29
Double_t ATan2(Double_t y, Double_t x)
Definition: TMath.h:669
static Double_t Phi_mpi_pi(Double_t x)
Returns phi angle in the interval [-PI,PI)
Definition: TVector2.cxx:101
virtual ~TVector2()
Definition: TVector2.cxx:57
constexpr Double_t Pi()
Definition: TMath.h:38
void Print(Option_t *option="") const
This method must be overridden when a class wants to print itself.
Definition: TVector2.cxx:152
TVector2()
Constructor.
Definition: TVector2.cxx:31
Double_t X() const
Definition: TVector2.h:72
unsigned int UInt_t
Definition: RtypesCore.h:42
Double_t Cos(Double_t)
Definition: TMath.h:631
virtual Int_t ReadClassBuffer(const TClass *cl, void *pointer, const TClass *onfile_class=0)=0
#define ClassImp(name)
Definition: Rtypes.h:365
Double_t Phi() const
Return vector phi.
Definition: TVector2.cxx:80
double Double_t
Definition: RtypesCore.h:55
void Printf(const char *fmt,...)
Double_t const kPI
Definition: TVector2.cxx:23
constexpr Double_t RadToDeg()
Conversion from radian to degree: .
Definition: TMath.h:74
virtual const char * GetTitle() const
Returns title of object.
Definition: TObject.cxx:401
Double_t Y() const
Definition: TVector2.h:73
Double_t Sin(Double_t)
Definition: TMath.h:627
TVector2 Unit() const
Return module normalized to 1.
Definition: TVector2.cxx:72
void SetMagPhi(Double_t mag, Double_t phi)
Set vector using mag and phi.
Definition: TVector2.cxx:122
Double_t Sqrt(Double_t x)
Definition: TMath.h:681
Double_t Mod2() const
Definition: TVector2.h:67
virtual const char * GetName() const
Returns name of object.
Definition: TObject.cxx:357
Double_t Mod() const
Return modulo of this vector.
Definition: TVector2.cxx:64
virtual Version_t ReadVersion(UInt_t *start=0, UInt_t *bcnt=0, const TClass *cl=0)=0