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Functions
P4Helpers Namespace Reference

P4Helpers provides static helper functions for kinematic calculation on objects deriving from I4Momentum. More...

Functions

double deltaPhi (double phiA, double phiB)
 delta Phi in range [-pi,pi[ More...
 
double deltaEta (const I4Momentum &p1, const I4Momentum &p2)
 Computes efficiently \( \Delta{\eta} \). More...
 
double deltaEtaSq (const I4Momentum &p1, const I4Momentum &p2)
 Computes efficiently \( \Delta{\eta}^2 \). More...
 
double deltaEta (const I4Momentum *const p1, const I4Momentum *const p2)
 Computes efficiently \( \Delta{\eta} \), pointer args. More...
 
double deltaPhi (const I4Momentum &p4, const double phi)
 delta Phi in range [-pi,pi[ from one I4momentum reference More...
 
double deltaPhi (const I4Momentum &pA, const I4Momentum &pB)
 delta Phi in range [-pi,pi[ from two I4momentum references More...
 
double deltaPhiSq (const I4Momentum &pA, const I4Momentum &pB)
 delta Phi squared in range ([-pi,pi[)^2 from two I4momentum references More...
 
double deltaPhi (const I4Momentum *const pA, const I4Momentum *const pB)
 delta Phi in range [-pi,pi[ from two I4momentum pointers More...
 
double deltaR (const I4Momentum &p4, double eta, double phi)
 \( \Delta{R} \) from 1 I4Momentum More...
 
double deltaR (const I4Momentum &pA, const I4Momentum &pB)
 delta R from two I4momentum reference More...
 
double deltaR (const I4Momentum *const pA, const I4Momentum *const pB)
 delta R from two I4momentum pointers More...
 
bool isInDeltaR (const I4Momentum &p1, const I4Momentum &p2, double dR)
 Check if 2 I4Momentum are in a \( \Delta{R} \) cone. More...
 
double invMass (const I4Momentum &pA, const I4Momentum &pB)
 invariant mass from two I4momentum references More...
 
double invMass (const I4Momentum *const pA, const I4Momentum *const pB)
 invariant mass from two I4momentum pointers More...
 
double invMass (const I4Momentum &pA, const I4Momentum &pB, const I4Momentum &pC, const I4Momentum &pD)
 invariant mass from four I4momentum references More...
 
double invMass (const I4Momentum *const pA, const I4Momentum *const pB, const I4Momentum *const pC, const I4Momentum *const pD)
 invariant mass from four I4momentum pointers More...
 
template<class Iterator_t , class Predicate_t >
void sort (Iterator_t itr, Iterator_t itrEnd, Predicate_t p)
 sort a container according to the given predicate More...
 
template<class Container_t , class Predicate_t >
void sort (Container_t &container, Predicate_t p)
 sort a container according to the given predicate More...
 
template<class Container_t >
bool closestDeltaR (const double eta, const double phi, Container_t &coll, std::size_t &index, double &deltaR)
 Find the closest element in a collection to an I4Momentum. More...
 
template<class Container_t >
bool closestDeltaR (const I4Momentum &p4, Container_t &coll, std::size_t &index, double &deltaR)
 Find the closest element in a collection to an I4Momentum. More...
 
template<class Container_t >
bool closestDeltaR (const double eta, const double phi, const double ene, Container_t &coll, std::size_t &index, double &deltaR, double &deltaE)
 find the closest element in R - with a condition on E More...
 
template<class Container_t >
bool closestDeltaR (const I4Momentum &p4, Container_t &coll, std::size_t &index, double &deltaR, double &deltaE)
 find the closest element in R - with a condition on E More...
 

Detailed Description

P4Helpers provides static helper functions for kinematic calculation on objects deriving from I4Momentum.

Author
David Rousseau rouss.nosp@m.eau@.nosp@m.lal.i.nosp@m.n2p3.nosp@m..fr
Sebastien Binet binet.nosp@m.@cer.nosp@m.n.ch
Tadashi Maeno

Function Documentation

◆ closestDeltaR() [1/4]

template<class Container_t >
bool P4Helpers::closestDeltaR ( const double  eta,
const double  phi,
const double  ene,
Container_t &  coll,
std::size_t &  index,
double &  deltaR,
double &  deltaE 
)
inline

find the closest element in R - with a condition on E

Parameters
index[out] index of the closest element
deltaR[out] \( \Delta{R} \)
deltaE[out] \( \Delta{E} \)
Returns
true if found

Definition at line 331 of file P4Helpers.h.

334  {
335  using std::abs;
336  deltaR = deltaE = std::numeric_limits<double>::max(); // big value
337  bool l_return = false;
338  std::size_t l_idx = 0;
339  typename Container_t::const_iterator it = coll.begin();
340  typename Container_t::const_iterator itE = coll.end();
341  for (; it != itE; ++it,++l_idx) {
342  const double dE = abs( ene - (*it)->e() );
343  if ( CxxUtils::fpcompare::less(dE, deltaE) ) {
344  const double rtu = P4Helpers::deltaR(**it,eta,phi);
345  if ( CxxUtils::fpcompare::less(rtu, deltaR) ) {
346  index = l_idx;
347  deltaR = rtu;
348  deltaE = dE;
349  l_return = true;
350  }
351  }
352  }
353  return l_return;
354  }

◆ closestDeltaR() [2/4]

template<class Container_t >
bool P4Helpers::closestDeltaR ( const double  eta,
const double  phi,
Container_t &  coll,
std::size_t &  index,
double &  deltaR 
)
inline

Find the closest element in a collection to an I4Momentum.

Parameters
index[out] index of the closest element
deltaR[out] \( \Delta{R} \)
Returns
true if found

Definition at line 292 of file P4Helpers.h.

294  {
295  deltaR = std::numeric_limits<double>::max(); // big value
296  bool l_return = false;
297  std::size_t l_idx = 0;
298  typename Container_t::const_iterator it = coll.begin();
299  typename Container_t::const_iterator itE = coll.end();
300  for (; it != itE; ++it,++l_idx) {
301  double rtu = P4Helpers::deltaR(**it, eta, phi);
302  if ( CxxUtils::fpcompare::less(rtu, deltaR) ) {
303  index = l_idx;
304  deltaR = rtu;
305  l_return = true;
306  }
307  }
308  return l_return;
309  }

◆ closestDeltaR() [3/4]

template<class Container_t >
bool P4Helpers::closestDeltaR ( const I4Momentum &  p4,
Container_t &  coll,
std::size_t &  index,
double &  deltaR 
)
inline

Find the closest element in a collection to an I4Momentum.

Parameters
index[out] index of the closest element
deltaR[out] \( \Delta{R} \)
Returns
true if found

Definition at line 317 of file P4Helpers.h.

319  {
320  return P4Helpers::closestDeltaR( p4.eta(), p4.phi(),
321  coll, index, deltaR );
322  }

◆ closestDeltaR() [4/4]

template<class Container_t >
bool P4Helpers::closestDeltaR ( const I4Momentum &  p4,
Container_t &  coll,
std::size_t &  index,
double &  deltaR,
double &  deltaE 
)
inline

find the closest element in R - with a condition on E

Parameters
index[out] index of the closest element
deltaR[out] \( \Delta{R} \)
deltaE[out] \( \Delta{E} \)
Returns
false if found

Definition at line 363 of file P4Helpers.h.

366  {
367  return P4Helpers::closestDeltaR( p4.eta(), p4.phi(), p4.e(),
368  coll, index, deltaR, deltaE );
369  }

◆ deltaEta() [1/2]

double P4Helpers::deltaEta ( const I4Momentum &  p1,
const I4Momentum &  p2 
)
inline

Computes efficiently \( \Delta{\eta} \).

Definition at line 53 of file P4Helpers.h.

54  {
55  double dEta(999);
56  if ( p1.kind() == I4Momentum::P4PXPYPZE && p2.kind() == I4Momentum::P4PXPYPZE )
57  {
58  const double mom1 = p1.p(); const double pz1 = p1.pz();
59  const double mom2 = p2.p(); const double pz2 = p2.pz();
60  if ( ( mom1 + pz1 ) * ( mom2 - pz2 ) > 0 )
61  dEta = -0.5 * std::log( ( mom1 - pz1 ) / ( mom1 + pz1 )
62  * ( mom2 + pz2 ) / ( mom2 - pz2 ) );
63  }
64  else if ( p1.kind() == I4Momentum::P4PXPYPZE )
65  {
66  const double mom1 = p1.p(); const double pz1 = p1.pz();
67  if ( mom1 + pz1 > 0 )
68  dEta = -0.5 * std::log( ( mom1 - pz1 ) / ( mom1 + pz1 ) ) - p2.eta();
69  }
70  else if ( p2.kind() == I4Momentum::P4PXPYPZE )
71  {
72  const double mom2 = p2.p(); const double pz2 = p2.pz();
73  if ( mom2 - pz2 > 0 )
74  dEta = p1.eta() - 0.5 * std::log( ( mom2 + pz2 ) / ( mom2 - pz2 ) );
75  }
76  else
77  {
78  dEta = p1.eta() - p2.eta();
79  }
80  return dEta;
81  }

◆ deltaEta() [2/2]

double P4Helpers::deltaEta ( const I4Momentum *const  p1,
const I4Momentum *const  p2 
)
inline

Computes efficiently \( \Delta{\eta} \), pointer args.

Definition at line 127 of file P4Helpers.h.

128  {
129  return deltaEta(*p1, *p2);
130  }

◆ deltaEtaSq()

double P4Helpers::deltaEtaSq ( const I4Momentum &  p1,
const I4Momentum &  p2 
)
inline

Computes efficiently \( \Delta{\eta}^2 \).

Definition at line 85 of file P4Helpers.h.

86  {
87  double dEtaSq(999);
88  if ( p1.kind() == I4Momentum::P4PXPYPZE && p2.kind() == I4Momentum::P4PXPYPZE )
89  {
90  const double mom1 = p1.p(); const double pz1 = p1.pz();
91  const double mom2 = p2.p(); const double pz2 = p2.pz();
92  if ( ( mom1 + pz1 ) * ( mom2 - pz2 ) > 0 )
93  {
94  dEtaSq = std::log( ( mom1 - pz1 ) / ( mom1 + pz1 )
95  * ( mom2 + pz2 ) / ( mom2 - pz2 ) );
96  dEtaSq = 0.25 * dEtaSq * dEtaSq;
97  }
98  }
99  else if ( p1.kind() == I4Momentum::P4PXPYPZE )
100  {
101  const double mom1 = p1.p(); const double pz1 = p1.pz();
102  if ( mom1 + pz1 > 0 )
103  {
104  dEtaSq = - 0.5 * std::log( ( mom1 - pz1 ) / ( mom1 + pz1 ) ) - p2.eta();
105  dEtaSq = dEtaSq * dEtaSq;
106  }
107  }
108  else if ( p2.kind() == I4Momentum::P4PXPYPZE )
109  {
110  const double mom2 = p2.p(); const double pz2 = p2.pz();
111  if ( mom2 - pz2 > 0 )
112  {
113  dEtaSq = p1.eta() - 0.5 * std::log( ( mom2 + pz2 ) / ( mom2 - pz2 ) );
114  dEtaSq = dEtaSq * dEtaSq;
115  }
116  }
117  else
118  {
119  dEtaSq = p1.eta() - p2.eta();
120  dEtaSq = dEtaSq * dEtaSq;
121  }
122  return dEtaSq;
123  }

◆ deltaPhi() [1/4]

double P4Helpers::deltaPhi ( const I4Momentum &  p4,
const double  phi 
)
inline

delta Phi in range [-pi,pi[ from one I4momentum reference

Definition at line 134 of file P4Helpers.h.

135  {
136  return P4Helpers::deltaPhi( p4.phi(), phi );
137  }

◆ deltaPhi() [2/4]

double P4Helpers::deltaPhi ( const I4Momentum &  pA,
const I4Momentum &  pB 
)
inline

delta Phi in range [-pi,pi[ from two I4momentum references

Definition at line 141 of file P4Helpers.h.

142  {
143  double dPhi(999);
144  if ( pA.kind() == I4Momentum::P4PXPYPZE && pB.kind() == I4Momentum::P4PXPYPZE )
145  {
146  double xp = pA.px() * pB.px() ;
147  double xyp1 = 0;
148  if ( xp != 0 )
149  {
150  xyp1 = 1.0 + pA.py() * pB.py() / xp ;
151  dPhi = 0;
152  if ( xyp1 != 0 )
153  dPhi = atan( ( pA.py() / pA.px() - pB.py() / pB.px() ) / xyp1 );
154  if ( xyp1 < 0 )
155  {
156  if ( pA.py() / pA.px() > 0 )
157  dPhi += M_PI;
158  else
159  dPhi -= M_PI;
160  }
161  }
162  }
163  else
164  {
165  dPhi = remainder( -pA.phi() + pB.phi(), 2*M_PI );
166  }
167  return dPhi;
168  }

◆ deltaPhi() [3/4]

double P4Helpers::deltaPhi ( const I4Momentum *const  pA,
const I4Momentum *const  pB 
)
inline

delta Phi in range [-pi,pi[ from two I4momentum pointers

Definition at line 191 of file P4Helpers.h.

192  { return deltaPhi( pA->phi(), pB->phi() ); }

◆ deltaPhi() [4/4]

double P4Helpers::deltaPhi ( double  phiA,
double  phiB 
)
inline

delta Phi in range [-pi,pi[

Definition at line 29 of file P4Helpers.h.

30  {
31  return -remainder( -phiA + phiB, 2*M_PI );
32  }

◆ deltaPhiSq()

double P4Helpers::deltaPhiSq ( const I4Momentum &  pA,
const I4Momentum &  pB 
)
inline

delta Phi squared in range ([-pi,pi[)^2 from two I4momentum references

Definition at line 172 of file P4Helpers.h.

173  {
174  double dPhiSq(999);
175  if ( pA.kind() == I4Momentum::P4PXPYPZE && pB.kind() == I4Momentum::P4PXPYPZE )
176  {
177  double cosPhi = ( pA.px() * pB.px() + pA.py() * pB.py() ) / pA.pt() / pB.pt();
178  double phi = acos(cosPhi);
179  dPhiSq = phi*phi;
180  }
181  else
182  {
183  dPhiSq = remainder( -pA.phi() + pB.phi(), 2*M_PI );
184  dPhiSq = dPhiSq * dPhiSq;
185  }
186  return dPhiSq;
187  }

◆ deltaR() [1/3]

double P4Helpers::deltaR ( const I4Momentum &  p4,
double  eta,
double  phi 
)
inline

\( \Delta{R} \) from 1 I4Momentum

Definition at line 196 of file P4Helpers.h.

197  {
198  using std::sqrt;
199  const double dEta = p4.eta() - eta;
200  const double dPhi = P4Helpers::deltaPhi( p4, phi );
201  return sqrt( dEta*dEta + dPhi*dPhi );
202  }

◆ deltaR() [2/3]

double P4Helpers::deltaR ( const I4Momentum &  pA,
const I4Momentum &  pB 
)
inline

delta R from two I4momentum reference

Definition at line 206 of file P4Helpers.h.

207  {
208  using std::sqrt;
209  const double dEtaSq = P4Helpers::deltaEtaSq( pA, pB );
210  const double dPhiSq = P4Helpers::deltaPhiSq( pA, pB );
211  return sqrt( dEtaSq + dPhiSq );
212  }

◆ deltaR() [3/3]

double P4Helpers::deltaR ( const I4Momentum *const  pA,
const I4Momentum *const  pB 
)
inline

delta R from two I4momentum pointers

Definition at line 216 of file P4Helpers.h.

217  { return P4Helpers::deltaR( *pA, *pB ); }

◆ invMass() [1/4]

double P4Helpers::invMass ( const I4Momentum &  pA,
const I4Momentum &  pB 
)
inline

invariant mass from two I4momentum references

Definition at line 239 of file P4Helpers.h.

240  { return (pA.hlv()+pB.hlv()).m(); }

◆ invMass() [2/4]

double P4Helpers::invMass ( const I4Momentum &  pA,
const I4Momentum &  pB,
const I4Momentum &  pC,
const I4Momentum &  pD 
)
inline

invariant mass from four I4momentum references

Definition at line 249 of file P4Helpers.h.

251  { return (pA.hlv()+pB.hlv()+pC.hlv()+pD.hlv()).m(); }

◆ invMass() [3/4]

double P4Helpers::invMass ( const I4Momentum *const  pA,
const I4Momentum *const  pB 
)
inline

invariant mass from two I4momentum pointers

Definition at line 244 of file P4Helpers.h.

245  { return invMass( *pA, *pB ); }

◆ invMass() [4/4]

double P4Helpers::invMass ( const I4Momentum *const  pA,
const I4Momentum *const  pB,
const I4Momentum *const  pC,
const I4Momentum *const  pD 
)
inline

invariant mass from four I4momentum pointers

Definition at line 255 of file P4Helpers.h.

257  { return invMass( *pA, *pB, *pC, *pD ); }

◆ isInDeltaR()

bool P4Helpers::isInDeltaR ( const I4Momentum &  p1,
const I4Momentum &  p2,
double  dR 
)
inline

Check if 2 I4Momentum are in a \( \Delta{R} \) cone.

Parameters
dR[in] \( \Delta{R} \)
Returns
true if they are

Definition at line 223 of file P4Helpers.h.

225  {
226  using std::abs;
227  using std::sqrt;
228  const double dPhi = abs( P4Helpers::deltaPhi(p1,p2) ); // in [-pi,pi)
229  if ( dPhi > dR ) return false; // <==
230  const double dEta = abs( P4Helpers::deltaEta(p1,p2) );
231  if ( dEta > dR ) return false; // <==
232  const double deltaR2 = dEta*dEta + dPhi*dPhi;
233  if ( deltaR2 > dR*dR ) return false; // <==
234  return true;
235  }

◆ sort() [1/2]

template<class Container_t , class Predicate_t >
void P4Helpers::sort ( Container_t &  container,
Predicate_t  p 
)
inline

sort a container according to the given predicate

Definition at line 277 of file P4Helpers.h.

278  {
279  return P4Helpers::sort( container.begin(), container.end(), p );
280  }

◆ sort() [2/2]

template<class Iterator_t , class Predicate_t >
void P4Helpers::sort ( Iterator_t  itr,
Iterator_t  itrEnd,
Predicate_t  p 
)
inline

sort a container according to the given predicate

Definition at line 266 of file P4Helpers.h.

267  {
268  // Koenig's look-up at our rescue: handle correctly DataVector's
269  // special sort method. => We inject the std::sort into our namespace
270  using std::sort;
271  return sort( itr, itrEnd, p );
272  }
I4Momentum::py
virtual double py() const =0
y component of momentum
P4Helpers::deltaEtaSq
double deltaEtaSq(const I4Momentum &p1, const I4Momentum &p2)
Computes efficiently .
Definition: P4Helpers.h:85
P4Helpers::closestDeltaR
bool closestDeltaR(const double eta, const double phi, Container_t &coll, std::size_t &index, double &deltaR)
Find the closest element in a collection to an I4Momentum.
Definition: P4Helpers.h:292
python.PerfMonSerializer.p
def p
Definition: PerfMonSerializer.py:743
max
#define max(a, b)
Definition: cfImp.cxx:41
phi
Scalar phi() const
phi method
Definition: AmgMatrixBasePlugin.h:64
eta
Scalar eta() const
pseudorapidity method
Definition: AmgMatrixBasePlugin.h:79
index
Definition: index.py:1
I4Momentum::p
virtual double p() const =0
momentum magnitude
skel.it
it
Definition: skel.GENtoEVGEN.py:423
M_PI
#define M_PI
Definition: ActiveFraction.h:11
P4Helpers::invMass
double invMass(const I4Momentum *const pA, const I4Momentum *const pB, const I4Momentum *const pC, const I4Momentum *const pD)
invariant mass from four I4momentum pointers
Definition: P4Helpers.h:255
xAOD::P4Helpers::deltaR2
double deltaR2(double rapidity1, double phi1, double rapidity2, double phi2)
from bare rapidity,phi
Definition: xAODP4Helpers.h:111
I4Momentum::pt
virtual double pt() const =0
transverse momentum
I4Momentum::hlv
virtual CLHEP::HepLorentzVector hlv() const =0
CLHEP HepLorentzVector.
TruthTest.itE
itE
Definition: TruthTest.py:25
drawFromPickle.atan
atan
Definition: drawFromPickle.py:36
P4Helpers::deltaR
double deltaR(const I4Momentum *const pA, const I4Momentum *const pB)
delta R from two I4momentum pointers
Definition: P4Helpers.h:216
P4Helpers::deltaPhi
double deltaPhi(double phiA, double phiB)
delta Phi in range [-pi,pi[
Definition: P4Helpers.h:29
I4Momentum::pz
virtual double pz() const =0
z component of momentum
P4Helpers::deltaEta
double deltaEta(const I4Momentum &p1, const I4Momentum &p2)
Computes efficiently .
Definition: P4Helpers.h:53
I4Momentum::e
virtual double e() const =0
energy
TauGNNUtils::Variables::Track::dPhi
bool dPhi(const xAOD::TauJet &tau, const xAOD::TauTrack &track, double &out)
Definition: TauGNNUtils.cxx:530
I4Momentum::eta
virtual double eta() const =0
pseudo rapidity
P4Helpers::deltaR
double deltaR(const I4Momentum &p4, double eta, double phi)
from 1 I4Momentum
Definition: P4Helpers.h:196
I4Momentum::phi
virtual double phi() const =0
phi in [-pi,pi[
I4Momentum::kind
virtual Kind kind() const =0
tells what kind of P4XYZT this is
P4Helpers::deltaPhi
double deltaPhi(const I4Momentum *const pA, const I4Momentum *const pB)
delta Phi in range [-pi,pi[ from two I4momentum pointers
Definition: P4Helpers.h:191
P4Helpers::deltaPhiSq
double deltaPhiSq(const I4Momentum &pA, const I4Momentum &pB)
delta Phi squared in range ([-pi,pi[)^2 from two I4momentum references
Definition: P4Helpers.h:172
remainder
std::vector< std::string > remainder(const std::vector< std::string > &v1, const std::vector< std::string > &v2)
list of entries in a vector that are not in another
Definition: compareFlatTrees.cxx:44
CxxUtils::fpcompare::less
bool less(double a, double b)
Compare two FP numbers, working around x87 precision issues.
Definition: fpcompare.h:166
P4Helpers::sort
void sort(Iterator_t itr, Iterator_t itrEnd, Predicate_t p)
sort a container according to the given predicate
Definition: P4Helpers.h:266
P4Helpers::deltaEta
double deltaEta(const I4Momentum *const p1, const I4Momentum *const p2)
Computes efficiently , pointer args.
Definition: P4Helpers.h:127
python.CaloCondTools.log
log
Definition: CaloCondTools.py:20
P4Helpers::sort
void sort(Container_t &container, Predicate_t p)
sort a container according to the given predicate
Definition: P4Helpers.h:277
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bool dEta(const xAOD::TauJet &tau, const xAOD::TauTrack &track, double &out)
Definition: TauGNNUtils.cxx:525
I4Momentum::px
virtual double px() const =0
x component of momentum
I4Momentum::P4PXPYPZE
@ P4PXPYPZE
Definition: I4Momentum.h:33
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