genie::NuEKinematicsGenerator Class Reference

Generates kinematics for neutrino-electron events. Is a concrete implementation of the EventRecordVisitorI interface. More...

#include <NuEKinematicsGenerator.h>

Inheritance diagram for genie::NuEKinematicsGenerator:

Collaboration diagram for genie::NuEKinematicsGenerator:

Public Member Functions
	NuEKinematicsGenerator ()
	NuEKinematicsGenerator (string config)
	~NuEKinematicsGenerator ()
void	ProcessEventRecord (GHepRecord *event_rec) const
void	Configure (const Registry &config)
void	Configure (string config)
void	LoadConfig (void)
double	ComputeMaxXSec (const Interaction *in) const
double	Energy (const Interaction *in) const
Public Member Functions inherited from genie::EventRecordVisitorI
virtual	~EventRecordVisitorI ()
Public Member Functions inherited from genie::Algorithm
virtual	~Algorithm ()
virtual void	FindConfig (void)
virtual const Registry &	GetConfig (void) const
Registry *	GetOwnedConfig (void)
virtual const AlgId &	Id (void) const
	Get algorithm ID.
virtual AlgStatus_t	GetStatus (void) const
	Get algorithm status.
virtual bool	AllowReconfig (void) const
virtual AlgCmp_t	Compare (const Algorithm *alg) const
	Compare with input algorithm.
virtual void	SetId (const AlgId &id)
	Set algorithm ID.
virtual void	SetId (string name, string config)
const Algorithm *	SubAlg (const RgKey &registry_key) const
void	AdoptConfig (void)
void	AdoptSubstructure (void)
virtual void	Print (ostream &stream) const
	Print algorithm info.

Additional Inherited Members
Static Public Member Functions inherited from genie::Algorithm
static string	BuildParamVectKey (const std::string &comm_name, unsigned int i)
static string	BuildParamVectSizeKey (const std::string &comm_name)
static string	BuildParamMatKey (const std::string &comm_name, unsigned int i, unsigned int j)
static string	BuildParamMatRowSizeKey (const std::string &comm_name)
static string	BuildParamMatColSizeKey (const std::string &comm_name)
Protected Member Functions inherited from genie::KineGeneratorWithCache
	KineGeneratorWithCache ()
	KineGeneratorWithCache (string name)
	KineGeneratorWithCache (string name, string config)
	~KineGeneratorWithCache ()
virtual double	ComputeMaxXSec (const Interaction *in, const int nkey) const
virtual double	MaxXSec (GHepRecord *evrec, const int nkey=0) const
virtual double	FindMaxXSec (const Interaction *in, const int nkey=0) const
virtual void	CacheMaxXSec (const Interaction *in, double xsec, const int nkey=0) const
virtual CacheBranchFx *	AccessCacheBranch (const Interaction *in, const int nkey=0) const
virtual void	AssertXSecLimits (const Interaction *in, double xsec, double xsec_max) const
Protected Member Functions inherited from genie::EventRecordVisitorI
	EventRecordVisitorI ()
	EventRecordVisitorI (string name)
	EventRecordVisitorI (string name, string config)
Protected Member Functions inherited from genie::Algorithm
	Algorithm ()
	Algorithm (string name)
	Algorithm (string name, string config)
void	Initialize (void)
void	DeleteConfig (void)
void	DeleteSubstructure (void)
Registry *	ExtractLocalConfig (const Registry &in) const
Registry *	ExtractLowerConfig (const Registry &in, const string &alg_key) const
	Split an incoming configuration Registry into a block valid for the sub-algo identified by alg_key.
template<class T>
bool	GetParam (const RgKey &name, T &p, bool is_top_call=true) const
template<class T>
bool	GetParamDef (const RgKey &name, T &p, const T &def) const
template<class T>
int	GetParamVect (const std::string &comm_name, std::vector< T > &v, bool is_top_call=true) const
	Handle to load vectors of parameters.
int	GetParamVectKeys (const std::string &comm_name, std::vector< RgKey > &k, bool is_top_call=true) const
template<class T>
int	GetParamMat (const std::string &comm_name, TMatrixT< T > &mat, bool is_top_call=true) const
	Handle to load matrix of parameters.
template<class T>
int	GetParamMatSym (const std::string &comm_name, TMatrixTSym< T > &mat, bool is_top_call=true) const
int	GetParamMatKeys (const std::string &comm_name, std::vector< RgKey > &k, bool is_top_call=true) const
int	AddTopRegistry (Registry *rp, bool owns=true)
	add registry with top priority, also update ownership
int	AddLowRegistry (Registry *rp, bool owns=true)
	add registry with lowest priority, also update ownership
int	MergeTopRegistry (const Registry &r)
int	AddTopRegisties (const vector< Registry * > &rs, bool owns=false)
	Add registries with top priority, also udated Ownerships.
Protected Attributes inherited from genie::KineGeneratorWithCache
const XSecAlgorithmI *	fXSecModel
double	fSafetyFactor
	ComputeMaxXSec -> ComputeMaxXSec * fSafetyFactor.
std::vector< double >	vSafetyFactors
	MaxXSec -> MaxXSec * fSafetyFactors[nkey].
int	fNumOfSafetyFactors
	Number of given safety factors.
std::vector< string >	vInterpolatorTypes
	Type of interpolator for each key in a branch.
int	fNumOfInterpolatorTypes
	Number of given interpolators types.
double	fMaxXSecDiffTolerance
	max{100*(xsec-maxxsec)/.5*(xsec+maxxsec)} if xsec>maxxsec
double	fEMin
	min E for which maxxsec is cached - forcing explicit calc.
bool	fGenerateUniformly
	uniform over allowed phase space + event weight?
Protected Attributes inherited from genie::Algorithm
bool	fAllowReconfig
bool	fOwnsSubstruc
	true if it owns its substructure (sub-algs,...)
AlgId	fID
	algorithm name and configuration set
vector< Registry * >	fConfVect
vector< bool >	fOwnerships
	ownership for every registry in fConfVect
AlgStatus_t	fStatus
	algorithm execution status
AlgMap *	fOwnedSubAlgMp
	local pool for owned sub-algs (taken out of the factory pool)

Detailed Description

Generates kinematics for neutrino-electron events. Is a concrete implementation of the EventRecordVisitorI interface.

Author

Costas Andreopoulos <c.andreopoulos \at cern.ch> University of Liverpool

Created:\n July 13, 2005

License:\n Copyright (c) 2003-2025, The GENIE Collaboration

For the full text of the license visit http://copyright.genie-mc.org

Definition at line 27 of file NuEKinematicsGenerator.h.

Constructor & Destructor Documentation

NuEKinematicsGenerator() [1/2]

NuEKinematicsGenerator::NuEKinematicsGenerator

(

)

Definition at line 29 of file NuEKinematicsGenerator.cxx.

                                               :
KineGeneratorWithCache("genie::NuEKinematicsGenerator")
{
 
}

References genie::KineGeneratorWithCache::KineGeneratorWithCache().

NuEKinematicsGenerator() [2/2]

NuEKinematicsGenerator::NuEKinematicsGenerator

(

string

config

)

Definition at line 35 of file NuEKinematicsGenerator.cxx.

                                                            :
KineGeneratorWithCache("genie::NuEKinematicsGenerator", config)
{
 
}

References genie::KineGeneratorWithCache::KineGeneratorWithCache().

~NuEKinematicsGenerator()

NuEKinematicsGenerator::~NuEKinematicsGenerator

(

)

Definition at line 41 of file NuEKinematicsGenerator.cxx.

{
 
}

Member Function Documentation

ComputeMaxXSec()

double NuEKinematicsGenerator::ComputeMaxXSec ( const Interaction * in ) const

virtual

Implements genie::KineGeneratorWithCache.

Definition at line 145 of file NuEKinematicsGenerator.cxx.

{
// Computes the maximum differential cross section in the requested phase
// space. This method overloads KineGeneratorWithCache::ComputeMaxXSec
// method and the value is cached at a circular cache branch for retrieval
// during subsequent event generation.
// The computed max differential cross section does not need to be the exact
// maximum. The number used in the rejection method will be scaled up by a
// safety factor. But it needs to be fast - do not use a very small y step.
 
  const int N  = 40;
//const int Nb =  6;
 
  const KPhaseSpace & kps = interaction->PhaseSpace();
  Range1D_t yl = kps.Limits(kKVy);
  const double ymin = yl.min;
  const double ymax = yl.max;
 
  double max_xsec = -1.0;
 
  double dy = (ymax-ymin)/(N-1);
//double xseclast = -1;
//bool   increasing;
 
  for(int i=0; i<N; i++) {
    double y = ymin + i * dy;
    interaction->KinePtr()->Sety(y);
    double xsec = fXSecModel->XSec(interaction, kPSyfE);
 
    SLOG("NuEKinematics", pDEBUG) << "xsec(y = " << y << ") = " << xsec;
    max_xsec = TMath::Max(xsec, max_xsec);
/*
    increasing = xsec-xseclast>=0;
    xseclast   = xsec;
 
    // once the cross section stops increasing, I reduce the step size and
    // step backwards a little bit to handle cases that the max cross section
    // is grossly underestimated (very peaky distribution & large step)
    if(!increasing) {
       dy/=(Nb+1);
       for(int ib=0; ib<Nb; ib++) {
         y = y-dy;
         if(y<ymin) break;
         interaction->KinePtr()->Sety(y);
         xsec = fXSecModel->XSec(interaction, kPSyfE);
         SLOG("NuEKinematics", pDEBUG) << "xsec(y = " << y << ") = " << xsec;
         max_xsec = TMath::Max(xsec, max_xsec);
       }
       break;
    }
*/
  }//y
 
  // Apply safety factor, since value retrieved from the cache might
  // correspond to a slightly different energy.
  max_xsec *= fSafetyFactor;
 
  SLOG("NuEKinematics", pDEBUG) << interaction->AsString();
  SLOG("NuEKinematics", pDEBUG) << "Max xsec in phase space = " << max_xsec;
  SLOG("NuEKinematics", pDEBUG) << "Computed using alg = " << *fXSecModel;
 
  return max_xsec;
}

References genie::Interaction::AsString(), genie::KineGeneratorWithCache::fSafetyFactor, genie::KineGeneratorWithCache::fXSecModel, genie::Interaction::KinePtr(), genie::kKVy, genie::kPSyfE, genie::KPhaseSpace::Limits(), genie::Range1D_t::max, genie::Range1D_t::min, pDEBUG, genie::Interaction::PhaseSpace(), genie::Kinematics::Sety(), and SLOG.

Configure() [1/2]

void NuEKinematicsGenerator::Configure ( const Registry & config )

virtual

Configure the algorithm with an external registry The registry is merged with the top level registry if it is owned, Otherwise a copy of it is added with the highest priority

Reimplemented from genie::Algorithm.

Definition at line 220 of file NuEKinematicsGenerator.cxx.

{
  Algorithm::Configure(config);
  this->LoadConfig();
}

References genie::Algorithm::Configure(), and LoadConfig().

Configure() [2/2]

void NuEKinematicsGenerator::Configure ( string config )

virtual

Configure the algorithm from the AlgoConfigPool based on param_set string given in input An algorithm contains a vector of registries coming from different xml configuration files, which are loaded according a very precise prioriy This methods will load a number registries in order of priority: 1) "Tunable" parameter set from CommonParametes. This is loaded with the highest prioriry and it is designed to be used for tuning procedure Usage not expected from the user. 2) For every string defined in "CommonParame" the corresponding parameter set will be loaded from CommonParameter.xml 3) parameter set specified by the config string and defined in the xml file of the algorithm 4) if config is not "Default" also the Default parameter set from the same xml file will be loaded Effectively this avoids the repetion of a parameter when it is not changed in the requested configuration

Reimplemented from genie::Algorithm.

Definition at line 226 of file NuEKinematicsGenerator.cxx.

{
  Algorithm::Configure(config);
  this->LoadConfig();
}

References genie::Algorithm::Configure(), and LoadConfig().

Energy()

double NuEKinematicsGenerator::Energy ( const Interaction * in ) const

virtual

Reimplemented from genie::KineGeneratorWithCache.

Definition at line 210 of file NuEKinematicsGenerator.cxx.

{
// Override the base class Energy() method to cache the max xsec for the
// neutrino energy in the LAB rather than in the hit nucleon rest frame.
 
  const InitialState & init_state = interaction->InitState();
  double E = init_state.ProbeE(kRfLab);
  return E;
}

References genie::Interaction::InitState(), genie::kRfLab, and genie::InitialState::ProbeE().

LoadConfig()

void NuEKinematicsGenerator::LoadConfig

(

void

)

Definition at line 232 of file NuEKinematicsGenerator.cxx.

{
        GetParamDef( "MaxXSec-SafetyFactor", fSafetyFactor, 2.00 ) ;
        GetParamDef( "Cache-MinEnergy", fEMin, 1.00 ) ;
 
        GetParamDef("MaxXSec-DiffTolerance", fMaxXSecDiffTolerance, 0. ) ;
        assert(fMaxXSecDiffTolerance>=0);
 
  //-- Generate kinematics uniformly over allowed phase space and compute
  //   an event weight?
        GetParamDef( "UniformOverPhaseSpace", fGenerateUniformly, false ) ;
 
}

References genie::KineGeneratorWithCache::fEMin, genie::KineGeneratorWithCache::fGenerateUniformly, genie::KineGeneratorWithCache::fMaxXSecDiffTolerance, genie::KineGeneratorWithCache::fSafetyFactor, and genie::Algorithm::GetParamDef().

Referenced by Configure(), and Configure().

ProcessEventRecord()

void NuEKinematicsGenerator::ProcessEventRecord ( GHepRecord * event_rec ) const

virtual

Implements genie::EventRecordVisitorI.

Definition at line 46 of file NuEKinematicsGenerator.cxx.

{
  if(fGenerateUniformly) {
    LOG("NuEKinematics", pNOTICE)
          << "Generating kinematics uniformly over the allowed phase space";
  }
 
  //-- Get the random number generators
  RandomGen * rnd = RandomGen::Instance();
 
  //-- Access cross section algorithm for running thread
  RunningThreadInfo * rtinfo = RunningThreadInfo::Instance();
  const EventGeneratorI * evg = rtinfo->RunningThread();
  fXSecModel = evg->CrossSectionAlg();
 
  //-- For the subsequent kinematic selection with the rejection method:
  //   Calculate the max differential cross section or retrieve it from the
  //   cache. Throw an exception and quit the evg thread if a non-positive
  //   value is found.
  //   If the kinematics are generated uniformly over the allowed phase
  //   space the max xsec is irrelevant
  double xsec_max = (fGenerateUniformly) ? -1 : this->MaxXSec(evrec);
 
  //-- y range
  const KPhaseSpace & kps = evrec->Summary()->PhaseSpace();
  Range1D_t yl = kps.Limits(kKVy);
  double ymin = yl.min;
  double ymax = yl.max;
  double dy   = ymax-ymin;
 
  double xsec = -1;
  Interaction * interaction = evrec->Summary();
 
  //-- Try to select a valid inelastisity y
  unsigned int iter = 0;
  bool accept = false;
  while(1) {
     iter++;
     if(iter > kRjMaxIterations) {
        LOG("NuEKinematics", pWARN)
              << "*** Could not select a valid y after "
                                              << iter << " iterations";
        evrec->EventFlags()->SetBitNumber(kKineGenErr, true);
        genie::exceptions::EVGThreadException exception;
        exception.SetReason("Couldn't select kinematics");
        exception.SwitchOnFastForward();
        throw exception;
     }
 
     double y = ymin + dy * rnd->RndKine().Rndm();
     interaction->KinePtr()->Sety(y);
 
     LOG("NuEKinematics", pINFO) << "Trying: y = " << y;
 
     //-- computing cross section for the current kinematics
     xsec = fXSecModel->XSec(interaction, kPSyfE);
 
     //-- decide whether to accept the current kinematics
     if(!fGenerateUniformly) {
        this->AssertXSecLimits(interaction, xsec, xsec_max);
 
        double t = xsec_max * rnd->RndKine().Rndm();
        LOG("NuEKinematics", pDEBUG) << "xsec= "<< xsec<< ", J= 1, Rnd= "<< t;
 
        accept = (t<xsec);
     } else {
       accept = (xsec>0);
     }
 
     //-- If the generated kinematics are accepted, finish-up module's job
     if(accept) {
        LOG("NuEKinematics", pINFO) << "Selected: y = " << y;
 
        // set the cross section for the selected kinematics
        evrec->SetDiffXSec(xsec,kPSyfE);
 
        // for uniform kinematics, compute an event weight as
        // wght = (phase space volume)*(differential xsec)/(event total xsec)
         if(fGenerateUniformly) {
           double vol     = kinematics::PhaseSpaceVolume(interaction,kPSyfE);
           double totxsec = evrec->XSec();
           double wght    = (vol/totxsec)*xsec;
           LOG("NuEKinematics", pNOTICE)  << "Kinematics wght = "<< wght;
 
           // apply computed weight to the current event weight
           wght *= evrec->Weight();
           LOG("NuEKinematics", pNOTICE) << "Current event wght = " << wght;
           evrec->SetWeight(wght);
        }
 
        // lock selected kinematics & clear running values
        interaction->KinePtr()->Sety(y, true);
        interaction->KinePtr()->ClearRunningValues();
 
        return;
     }
  }// iterations
}

References genie::KineGeneratorWithCache::AssertXSecLimits(), genie::Kinematics::ClearRunningValues(), genie::EventGeneratorI::CrossSectionAlg(), genie::GHepRecord::EventFlags(), genie::KineGeneratorWithCache::fGenerateUniformly, genie::KineGeneratorWithCache::fXSecModel, genie::RandomGen::Instance(), genie::RunningThreadInfo::Instance(), genie::Interaction::KinePtr(), genie::kKineGenErr, genie::kKVy, genie::kPSyfE, genie::controls::kRjMaxIterations, genie::KPhaseSpace::Limits(), LOG, genie::Range1D_t::max, genie::KineGeneratorWithCache::MaxXSec(), genie::Range1D_t::min, pDEBUG, genie::Interaction::PhaseSpace(), genie::utils::kinematics::PhaseSpaceVolume(), pINFO, pNOTICE, pWARN, genie::RandomGen::RndKine(), genie::RunningThreadInfo::RunningThread(), genie::GHepRecord::SetDiffXSec(), genie::exceptions::EVGThreadException::SetReason(), genie::GHepRecord::SetWeight(), genie::Kinematics::Sety(), genie::GHepRecord::Summary(), genie::exceptions::EVGThreadException::SwitchOnFastForward(), genie::GHepRecord::Weight(), and genie::GHepRecord::XSec().

---

The documentation for this class was generated from the following files:

• NuEKinematicsGenerator.h
• NuEKinematicsGenerator.cxx