ATHRNG::RNGWrapper Class Reference

A wrapper class for event-slot-local random engines. More...

#include <RNGWrapper.h>

Collaboration diagram for ATHRNG::RNGWrapper:

Public Types
enum	SeedingOptionType { MC20Seeding =0, MC16Seeding =1, MC21Seeding =2, SeedingDefault =MC21Seeding }
	Options for seeding option=0 is setSeed as in MC20 option=1 is setSeedLegacy as in MC16 option=2 is setSeedImproved. More...

Public Member Functions
	RNGWrapper (const factoryFunc &genFact, size_t nSlots)
	Constructor takes a factory function which can instantiate a CLHEP::HepRandomEngine and the number of event slots. More...
	~RNGWrapper ()
void	setSeed (const std::string &algName, const EventContext &ctx)
	Set the random seed using a string (e.g. More...
void	setSeed (const std::string &algName, size_t slot, uint64_t ev, uint64_t run, EventContext::ContextEvt_t evt=EventContext::INVALID_CONTEXT_EVT)
	Set the random seed using a string (e.g. More...
void	setSeedMC16 (const std::string &algName, size_t slot, uint64_t ev, uint64_t run, uint32_t offset=0, EventContext::ContextEvt_t evt=EventContext::INVALID_CONTEXT_EVT)
	Set the random seed using a string (e.g. More...
void	setSeedMC20 (const std::string &algName, size_t slot, uint64_t ev, uint64_t run, EventContext::ContextEvt_t evt=EventContext::INVALID_CONTEXT_EVT)
	Set the random seed using a string (e.g. More...
void	setSeedMC21 (const std::string &algName, size_t slot, uint64_t ev, uint64_t run, uint64_t offset=0, EventContext::ContextEvt_t evt=EventContext::INVALID_CONTEXT_EVT)
	Set the random seed using a string (e.g. More...
void	setSeedLegacy (const std::string &algName, size_t slot, uint64_t ev, uint64_t run, uint64_t offset, SeedingOptionType seeding, EventContext::ContextEvt_t evt=EventContext::INVALID_CONTEXT_EVT)
	Set the random seed using a string (e.g. More...
void	setSeedLegacy (const std::string &algName, const EventContext &ctx, uint32_t offset, SeedingOptionType seeding, EventContext::ContextEvt_t evt=EventContext::INVALID_CONTEXT_EVT)
	Set the random seed using a string (e.g. More...
void	setSeed (size_t slot, size_t seed, EventContext::ContextEvt_t evt=EventContext::INVALID_CONTEXT_EVT)
	Set the seed value directly for a specified slot. More...
void	setSeeds (size_t slot, const long *seeds, EventContext::ContextEvt_t evt=EventContext::INVALID_CONTEXT_EVT)
	Set the seed value(s) directly for a specified slot. More...
	operator CLHEP::HepRandomEngine * () const
	Cast-to-engine pointer operator. More...
CLHEP::HepRandomEngine *	getEngine (const EventContext &ctx) const
	Retrieve the random engine corresponding to the provided EventContext. More...
EventContext::ContextEvt_t	evtSeeded () const
	Return the event count at which the current slot was last seeded. More...
EventContext::ContextEvt_t	evtSeeded (const EventContext &ctx) const
	Return the event count at which the current slot of CTX was last seeded. More...

Static Public Attributes
static constexpr std::initializer_list< SeedingOptionType >	all_SeedingOptions = {MC20Seeding, MC16Seeding, MC21Seeding}

Private Types
typedef std::function< CLHEP::HepRandomEngine *(void)>	factoryFunc

Private Attributes
std::vector< CLHEP::HepRandomEngine * >	m_engines
	Vector of random engines, ordered by slot number. More...
std::vector< EventContext::ContextEvt_t >	m_evtSeeded
	Event counter when the engine was last seeded. More...

Detailed Description

A wrapper class for event-slot-local random engines.

Implemented primarily for use in services implementing IAthRNGSvc for thread-safe random number generation in AthenaMT.

The slot-local HepRandomEngine is retrieved via the dereference operator or the getEngine method.

This class also provides a seed setting and generating mechanism. The seed is calculated from an algorithm name and the slot, event, and run numbers.

Author

Sami Kama sami..nosp@m.kama.nosp@m.@cern.nosp@m..ch

Steve Farrell Steve.nosp@m.n.Fa.nosp@m.rrell.nosp@m.@cer.nosp@m.n.ch

Definition at line 55 of file RNGWrapper.h.

Member Typedef Documentation

factoryFunc

typedef std::function<CLHEP::HepRandomEngine*(void)> ATHRNG::RNGWrapper::factoryFunc

private

Definition at line 58 of file RNGWrapper.h.

Member Enumeration Documentation

SeedingOptionType

enum ATHRNG::RNGWrapper::SeedingOptionType

Options for seeding option=0 is setSeed as in MC20 option=1 is setSeedLegacy as in MC16 option=2 is setSeedImproved.

Enumerator
MC20Seeding
MC16Seeding
MC21Seeding
SeedingDefault

Definition at line 97 of file RNGWrapper.h.

                           {
      MC20Seeding=0,
      MC16Seeding=1,
      MC21Seeding=2,
      SeedingDefault=MC21Seeding
    };    

Constructor & Destructor Documentation

RNGWrapper()

ATHRNG::RNGWrapper::RNGWrapper	(	const factoryFunc &	genFact,
		size_t	nSlots
	)

Constructor takes a factory function which can instantiate a CLHEP::HepRandomEngine and the number of event slots.

Definition at line 69 of file RNGWrapper.cxx.

{
  // Construct the random engines; one per event slot.
  m_engines.reserve(nSlots);
  for(size_t t = 0; t < nSlots; t++){
    m_engines.emplace_back(genFact());
  }
  m_evtSeeded.resize (nSlots, EventContext::INVALID_CONTEXT_EVT);
}

~RNGWrapper()

ATHRNG::RNGWrapper::~RNGWrapper

(

)

Definition at line 79 of file RNGWrapper.cxx.

{
  // Clean up the allocated engines
  for(auto engPtr : m_engines) {
    delete engPtr;
  }
}

Member Function Documentation

evtSeeded() [1/2]

EventContext::ContextEvt_t ATHRNG::RNGWrapper::evtSeeded ( ) const

inline

Return the event count at which the current slot was last seeded.

Definition at line 139 of file RNGWrapper.h.

    {
      return m_evtSeeded[Gaudi::Hive::currentContext().slot()];
    }

evtSeeded() [2/2]

EventContext::ContextEvt_t ATHRNG::RNGWrapper::evtSeeded ( const EventContext &  ctx ) const

inline

Return the event count at which the current slot of CTX was last seeded.

Definition at line 145 of file RNGWrapper.h.

    {
      return m_evtSeeded[ctx.slot()];
    }

getEngine()

CLHEP::HepRandomEngine* ATHRNG::RNGWrapper::getEngine ( const EventContext &  ctx ) const

inline

Retrieve the random engine corresponding to the provided EventContext.

Definition at line 134 of file RNGWrapper.h.

                                                                   {
      return m_engines[ctx.slot()];
    }

operator CLHEP::HepRandomEngine *()

ATHRNG::RNGWrapper::operator CLHEP::HepRandomEngine * ( ) const

inline

Cast-to-engine pointer operator.

Retrieves the current event context and returns the engine corresponding to the current event slot.

Definition at line 129 of file RNGWrapper.h.

                                           {
      return m_engines[Gaudi::Hive::currentContext().slot()];
    }

setSeed() [1/3]

void ATHRNG::RNGWrapper::setSeed ( const std::string &  algName, const EventContext &  ctx  )

inline

Set the random seed using a string (e.g.

algorithm name) and the current EventContext. Does nothing if the context is invalid.

Definition at line 169 of file RNGWrapper.h.

{
  setSeed( algName, ctx.slot(),
           ctx.eventID().event_number(),
           ctx.eventID().run_number(),
           ctx.evt() );
}

setSeed() [2/3]

void ATHRNG::RNGWrapper::setSeed ( const std::string &  algName, size_t  slot, uint64_t  ev, uint64_t  run, EventContext::ContextEvt_t  evt = EventContext::INVALID_CONTEXT_EVT  )

inline

Set the random seed using a string (e.g.

algorithm name) and the current slot, event, and run numbers.

Definition at line 163 of file RNGWrapper.h.

{
  setSeedMC21(algName,slot,ev,run,0,evt);
}

setSeed() [3/3]

void ATHRNG::RNGWrapper::setSeed	(	size_t	slot,
		size_t	seed,
		EventContext::ContextEvt_t	evt = EventContext::INVALID_CONTEXT_EVT
	)

Set the seed value directly for a specified slot.

Definition at line 129 of file RNGWrapper.cxx.

{
  m_engines[slot]->setSeed(seed, 0);
  if (evt == EventContext::INVALID_CONTEXT_EVT) {
    evt = Gaudi::Hive::currentContext().evt();
  }
  m_evtSeeded[slot] = evt;
}

setSeedLegacy() [1/2]

void ATHRNG::RNGWrapper::setSeedLegacy ( const std::string &  algName, const EventContext &  ctx, uint32_t  offset, SeedingOptionType  seeding, EventContext::ContextEvt_t  evt = EventContext::INVALID_CONTEXT_EVT  )

inline

Set the random seed using a string (e.g.

algorithm name) and the current EventContext and an optional offset. Does nothing if the context is invalid. - Version allowing to switch the seeding options

Definition at line 177 of file RNGWrapper.h.

{
  setSeedLegacy( algName, ctx.slot(),
                 ctx.eventID().event_number(),
                 ctx.eventID().run_number(),
                 offset, seeding, evt);
}

setSeedLegacy() [2/2]

void ATHRNG::RNGWrapper::setSeedLegacy	(	const std::string &	algName,
		size_t	slot,
		uint64_t	ev,
		uint64_t	run,
		uint64_t	offset,
		SeedingOptionType	seeding,
		EventContext::ContextEvt_t	evt = EventContext::INVALID_CONTEXT_EVT
	)

Set the random seed using a string (e.g.

algorithm name) and the current slot, event, and run numbers and an optional offset. - Version allowing to switch the seeding options

Definition at line 104 of file RNGWrapper.cxx.

{
  if(seeding==MC16Seeding) {
    // Use MC16 legacy seeding
    setSeedMC16(algName, slot, ev, run, offset, evt);
    return;
  }
  if(seeding==MC20Seeding) {
    // Use MC20 seeding
    setSeedMC20(algName, slot, ev, run, evt);
    return;
  }
  // Use MC21 seeding
  setSeedMC21(algName, slot, ev, run, offset, evt);
}

setSeedMC16()

void ATHRNG::RNGWrapper::setSeedMC16	(	const std::string &	algName,
		size_t	slot,
		uint64_t	ev,
		uint64_t	run,
		uint32_t	offset = 0,
		EventContext::ContextEvt_t	evt = EventContext::INVALID_CONTEXT_EVT
	)

Set the random seed using a string (e.g.

algorithm name) and the current slot, event, and run numbers and an optional offset. - MC16 Legacy Version attempting to reproduce seeds from thread-unsafe random number services

Definition at line 122 of file RNGWrapper.cxx.

{
  uint32_t theHash = calculateSeedMC16(algName, ev, run, offset);
  setSeed(slot, theHash, evt);
}

setSeedMC20()

void ATHRNG::RNGWrapper::setSeedMC20	(	const std::string &	algName,
		size_t	slot,
		uint64_t	ev,
		uint64_t	run,
		EventContext::ContextEvt_t	evt = EventContext::INVALID_CONTEXT_EVT
	)

Set the random seed using a string (e.g.

algorithm name) and the current slot, event, and run numbers. MC20 seeding algorithm

Definition at line 87 of file RNGWrapper.cxx.

{
  auto hsh = calculateSeedMC20(algName, ev, run);
  setSeed(slot, hsh, evt);
}

setSeedMC21()

void ATHRNG::RNGWrapper::setSeedMC21	(	const std::string &	algName,
		size_t	slot,
		uint64_t	ev,
		uint64_t	run,
		uint64_t	offset = 0,
		EventContext::ContextEvt_t	evt = EventContext::INVALID_CONTEXT_EVT
	)

Set the random seed using a string (e.g.

algorithm name) and the current slot, event, and run numbers. MC21 seeding algorithm

Definition at line 95 of file RNGWrapper.cxx.

{
  long seeds[7]; //CLHEP uses long for seeding
  calculateSeedsMC21(seeds, algName, ev, run, offset);
  setSeeds(slot, seeds, evt);
}

setSeeds()

void ATHRNG::RNGWrapper::setSeeds	(	size_t	slot,
		const long *	seeds,
		EventContext::ContextEvt_t	evt = EventContext::INVALID_CONTEXT_EVT
	)

Set the seed value(s) directly for a specified slot.

Definition at line 139 of file RNGWrapper.cxx.

{
  m_engines[slot]->setSeeds(seeds, 0);
  if (evt == EventContext::INVALID_CONTEXT_EVT) {
    evt = Gaudi::Hive::currentContext().evt();
  }
  m_evtSeeded[slot] = evt;
}

Member Data Documentation

all_SeedingOptions

constexpr std::initializer_list<SeedingOptionType> ATHRNG::RNGWrapper::all_SeedingOptions = {MC20Seeding, MC16Seeding, MC21Seeding}

staticconstexpr

Definition at line 103 of file RNGWrapper.h.

m_engines

std::vector<CLHEP::HepRandomEngine*> ATHRNG::RNGWrapper::m_engines

private

Vector of random engines, ordered by slot number.

Definition at line 153 of file RNGWrapper.h.

m_evtSeeded

std::vector<EventContext::ContextEvt_t> ATHRNG::RNGWrapper::m_evtSeeded

private

Event counter when the engine was last seeded.

Definition at line 156 of file RNGWrapper.h.

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

• RNGWrapper.h
• RNGWrapper.cxx