HepMcParticleLink Class Reference

a link optimized in size for a GenParticle in a McEventCollection More...

#include <HepMcParticleLink.h>

Collaboration diagram for HepMcParticleLink:

Classes
class	ExtendedBarCode
	Persistent representation of a link. More...

Public Types
enum	PositionFlag { IS_EVENTNUM = 0 , IS_POSITION = 1 }
enum	UniqueIDFlag { IS_ID = 0 , IS_BARCODE = 1 }
typedef uint32_t	barcode_type
typedef uint32_t	index_type

Public Member Functions
	HepMcParticleLink (IProxyDict *sg=nullptr)
	Default constructor.
	HepMcParticleLink (const EventContext &ctx)
	Default constructor.
	HepMcParticleLink (barcode_type uid, uint32_t eventIndex, PositionFlag positionFlag, UniqueIDFlag uniqueIDFlag, IProxyDict *sg)
	Constructor.
	HepMcParticleLink (barcode_type uid, uint32_t eventIndex, PositionFlag positionFlag, UniqueIDFlag uniqueIDFlag, const EventContext &ctx=Gaudi::Hive::currentContext())
	Constructor.
	HepMcParticleLink (const HepMC::ConstGenParticlePtr &p, uint32_t eventIndex, PositionFlag positionFlag, IProxyDict *sg)
	Constructor.
	HepMcParticleLink (const HepMC::ConstGenParticlePtr &part, uint32_t eventIndex, PositionFlag positionFlag, const EventContext &ctx=Gaudi::Hive::currentContext())
	Constructor.
	HepMcParticleLink (const HepMcParticleLink &rhs)=default
	Copy constructor.
	HepMcParticleLink (HepMcParticleLink &&rhs) noexcept=default
	Move constructor.
HepMcParticleLink &	operator= (const HepMcParticleLink &rhs)=default
	Assignment.
HepMcParticleLink &	operator= (HepMcParticleLink &&rhs)=default
	Move Assignment.
pointer interface
const HepMC::GenParticle &	operator* () const
	Dereference.
HepMC::ConstGenParticlePtr	operator-> () const
	Dereference.
	operator HepMC::ConstGenParticlePtr () const
	Dereference.
HepMC::ConstGenParticlePtr	cptr () const
	Dereference.
HepMC::ConstGenParticlePtr	scptr () const
	Dereference/smart pointer.
bool	linkIsNull () const
	return true if neither barcode nor id are valid
bool	isValid () const
	Validity check.
bool	operator! () const
	Validity check.
	operator bool () const
	Validity check.
Comparison operators.
bool	operator== (const HepMcParticleLink &rhs) const
	Equality comparison.
bool	operator!= (const HepMcParticleLink &rhs) const
	Inequality comparison.
bool	operator< (const HepMcParticleLink &rhs) const
	Ordering comparison.

ParticleLink-specific methods.
IProxyDict *	m_store
	Pointer to the store containing the event.
ATH_NO_UNIQUE_ADDRESS CxxUtils::CachedValue< HepMC::ConstGenParticlePtr >	m_ptr
	Transient part. Pointer to the particle.
ExtendedBarCode	m_extBarcode
	Persistent part: barcode and location of target GenEvent.
int	barcode () const
	Return the barcode of the target particle.
int	id () const
	Return the id of the target particle.
index_type	eventIndex () const
	Return the event number of the referenced GenEvent.
index_type	getEventPositionInCollection (IProxyDict *sg) const
	Return the position in the McEventCollection of the GenEvent pointed to by this HepMcParticleLink.
index_type	getEventPositionInCollection (const EventContext &ctx) const
	Return the position in the McEventCollection of the GenEvent pointed to by this HepMcParticleLink.
EBC_SUPPRESSED_TRUTH	getTruthSuppressionType () const
	Return whether the truth particle has been suppressed, as an enum.
void	setTruthSuppressionType (EBC_SUPPRESSED_TRUTH truthSupp)
	Return whether the truth particle has been suppressed.
char	getTruthSuppressionTypeAsChar () const
	Return whether the truth particle has been suppressed, as a char ('a'..'b').
barcode_type	compress () const
	Hash the 32 bit barcode and 16 bit eventindex into a 32bit int.
void	setExtendedBarCode (const ExtendedBarCode &extBarcode)
	Alter the persistent part of the link.
static int	getEventNumberAtPosition (index_type position, IProxyDict *sg)
	Return the event number of the GenEvent at the specified position in the McEventCollection.
static int	getEventNumberAtPosition (index_type position, const EventContext &ctx)
	Return the event number of the GenEvent at the specified position in the McEventCollection.
static std::vector< index_type >	getEventPositionInCollection (index_type index, IProxyDict *sg)
	Return a vector of the positions in the McEventCollection of the GenEvent(s) with a given event number.
static HepMcParticleLink	getRedirectedLink (const HepMcParticleLink &particleLink, uint32_t eventIndex, const EventContext &ctx)
	Return a HepMcParticleLink pointing at the same particle, but in a different GenEvent.
std::ostream &	operator<< (std::ostream &os, const HepMcParticleLink &link)
	Output operator.
MsgStream &	operator<< (MsgStream &os, const HepMcParticleLink &link)
	Output operator.
static const McEventCollection *	retrieveMcEventCollection (IProxyDict *sg)
	Look up the event collection we're targeting.
static SG::DataProxy *	find_proxy (IProxyDict *sg)
	Find the proxy for the target event collection.
static std::string	getLastEventCollectionName ()
	Return the most recent SG key used for a particular collection type.

Detailed Description

a link optimized in size for a GenParticle in a McEventCollection

A link is defined by three items:

• A target McEventCollection;
• A particular GenEvent within this collection; and
• A particular particle within the GenEvent.

There is a list of StoreGate keys for the McEventCollection (see the initialization of s_keys). When we want to dereference the link, we try to look up each possible key in turn until we find one that works. (The position of that key in the list is then remembered as a hint for where to start searching next time.)

The particular GenEvent within the collection can be represented as either an event number (as returned by GenEvent::event_number()) or by a position within the collection. Which case is desired is indicated by the value of the isIndexEventPosition argument to the constructors (defaulting to the event number case). In order to convert between these, we need to retrieve the McEventCollection from the store, but we don't have the store pointer once the link has been dereferenced. Therefore, when a position-based link is dereferenced, it is automatically changed to be event-number-based. This also happens when a link is constructed with an explicit ConstGenParticlePtr and a position-based GenEvent.

As a special case, a GenEvent number of 0 is interpreted as the first GenEvent in the collection.

The particle within the GenEvent is represented by a unique ID. A unique ID of 0 implies a null link.

In order to dereference a link, we need to reference a particular event store. By default, the current store (as defined by the current EventContext) is stored when the link is constructed; however, an explicit IProxyDict* or EventContext may also be specified.

See also

McEventCollection, GenEvent, ElementLink

Author

Paolo Calafiura

Definition at line 71 of file HepMcParticleLink.h.

Member Typedef Documentation

barcode_type

typedef uint32_t HepMcParticleLink::barcode_type

Definition at line 74 of file HepMcParticleLink.h.

index_type

typedef uint32_t HepMcParticleLink::index_type

Definition at line 75 of file HepMcParticleLink.h.

Member Enumeration Documentation

PositionFlag

enum HepMcParticleLink::PositionFlag

Enumerator
IS_EVENTNUM
IS_POSITION

Definition at line 78 of file HepMcParticleLink.h.

                    {
    IS_EVENTNUM = 0,
    IS_POSITION = 1,
  };

UniqueIDFlag

enum HepMcParticleLink::UniqueIDFlag

Enumerator
IS_ID
IS_BARCODE

Definition at line 83 of file HepMcParticleLink.h.

                    {
    IS_ID = 0,
    IS_BARCODE = 1,
  };

Constructor & Destructor Documentation

HepMcParticleLink() [1/8]

HepMcParticleLink::HepMcParticleLink

(

IProxyDict *

sg = nullptr

)

Default constructor.

Makes a null link.

Parameters

sg	Optional specification of a specific store to reference.

HepMcParticleLink() [2/8]

HepMcParticleLink::HepMcParticleLink

(

const EventContext &

ctx

)

Default constructor.

Makes a null link.

Parameters

ctx	Context of the store to reference.

HepMcParticleLink() [3/8]

HepMcParticleLink::HepMcParticleLink	(	barcode_type	uid,
		uint32_t	eventIndex,
		PositionFlag	positionFlag,
		UniqueIDFlag	uniqueIDFlag,
		IProxyDict *	sg )

Constructor.

Parameters

uid	Unique ID of the target particle. 0 means a null link.
eventIndex	Identifies the target GenEvent in a McEventCollection, as either the event number if isIndexEventPosition is IS_EVENTNUM, or the position in the container if isIndexEventPosition is IS_POSITION. 0 always means the first event in the collection.
positionFlag	See eventIndex.
sg	Optional specification of a specific store to reference.

HepMcParticleLink() [4/8]

HepMcParticleLink::HepMcParticleLink	(	barcode_type	uid,
		uint32_t	eventIndex,
		PositionFlag	positionFlag,
		UniqueIDFlag	uniqueIDFlag,
		const EventContext &	ctx = Gaudi::Hive::currentContext() )

Constructor.

Parameters

uid	Unique ID of the target particle. 0 means a null link.
eventIndex	Identifies the target GenEvent in a McEventCollection, as either the event number if isIndexEventPosition is IS_EVENTNUM, or the position in the container if isIndexEventPosition is IS_POSITION. 0 always means the first event in the collection.
positionFlag	See eventIndex.
ctx	Context of the store to reference.

HepMcParticleLink() [5/8]

HepMcParticleLink::HepMcParticleLink	(	const HepMC::ConstGenParticlePtr &	part,
		uint32_t	eventIndex,
		PositionFlag	positionFlag,
		IProxyDict *	sg )

Constructor.

Parameters

p	Particle to reference.
eventIndex	Identifies the target GenEvent in a McEventCollection, as either the event number if isIndexEventPosition is IS_EVENTNUM, or the position in the container if isIndexEventPosition is IS_POSITION. 0 always means the first event in the collection.
positionFlag	See eventIndex.
sg	Optional specification of a specific store to reference.

Definition at line 144 of file HepMcParticleLink.cxx.

  : m_store (sg),
    m_ptr (part),
    m_extBarcode((nullptr != part) ? HepMC::uniqueID(part) : 0, eventIndex, positionFlag, IS_ID)
{
  assert(part);
 
  if (part != nullptr && positionFlag == IS_POSITION) {
    if (const McEventCollection* pEvtColl = retrieveMcEventCollection(sg)) {
      const HepMC::GenEvent *pEvt = pEvtColl->at (eventIndex);
      m_extBarcode.makeIndex (pEvt->event_number(), eventIndex);
    }
    else {
      MsgStream log (Athena::getMessageSvc(), "HepMcParticleLink");
      log << MSG::WARNING << "cptr: McEventCollection not found" << endmsg;
    }
  }
}

HepMcParticleLink() [6/8]

HepMcParticleLink::HepMcParticleLink	(	const HepMC::ConstGenParticlePtr &	part,
		uint32_t	eventIndex,
		PositionFlag	positionFlag,
		const EventContext &	ctx = Gaudi::Hive::currentContext() )

Constructor.

Parameters

p	Particle to reference.
eventIndex	Identifies the target GenEvent in a McEventCollection, as either the event number if isIndexEventPosition is IS_EVENTNUM, or the position in the container if isIndexEventPosition is IS_POSITION. 0 always means the first event in the collection.
positionFlag	See eventIndex.
ctx	Context of the store to reference.

HepMcParticleLink() [7/8]

HepMcParticleLink::HepMcParticleLink ( const HepMcParticleLink & rhs )

default

Copy constructor.

HepMcParticleLink() [8/8]

HepMcParticleLink::HepMcParticleLink ( HepMcParticleLink && rhs )

defaultnoexcept

Move constructor.

Member Function Documentation

barcode()

int HepMcParticleLink::barcode

(

)

const

Return the barcode of the target particle.

0 for a null link. FIXME: return type.

Definition at line 311 of file HepMcParticleLink.cxx.

{
  // if m_BC is zero (delta rays), then just return that same for barcode and id
  if (m_extBarcode.uid()) {
    barcode_type particle_id, particle_barcode;
    m_extBarcode.uniqueID (particle_id, particle_barcode);
    if (particle_barcode != ExtendedBarCode::UNDEFINEDBC) {
      return int(particle_barcode);
    }
    // dummy link
    if (!m_ptr.isValid() && !m_store) {
      return 0; // TODO Decide if this is a good default - constant from MagicNumbers.h instead?
    }
    // we will need to look up the barcode from the GenParticle
    (void) eventIndex(); // FIXME be careful to avoid an infinite loop of calls here
    if (cptr()) {
      return HepMC::barcode(cptr());
    }
  }
  return 0;
}

compress()

barcode_type HepMcParticleLink::compress

(

)

const

Hash the 32 bit barcode and 16 bit eventindex into a 32bit int.

cptr()

HepMC::ConstGenParticlePtr HepMcParticleLink::cptr

(

)

const

Dereference.

Definition at line 178 of file HepMcParticleLink.cxx.

{
  // dummy link
  const bool is_valid = m_ptr.isValid();
  if (!is_valid && !m_store) {
    return nullptr;
  }
  if (is_valid) {
    return *m_ptr.ptr();
  }
  if (m_extBarcode.linkIsNull()) {
    #if 0
    MsgStream log (Athena::getMessageSvc(), "HepMcParticleLink");
    log << MSG::DEBUG
        << "cptr: no truth particle associated with this hit (barcode==0)."
        << " Probably this is a noise hit" << endmsg;
    #endif
    return nullptr;
  }
  IProxyDict* sg = m_store;
  if (!sg) {
    sg = Atlas::proxyDictFromEventContext();
  }
  if (const McEventCollection* pEvtColl = retrieveMcEventCollection(sg)) {
    const HepMC::GenEvent *pEvt = nullptr;
    index_type event_number, position;
    m_extBarcode.eventIndex (event_number, position);
    if (event_number == 0) {
      pEvt = pEvtColl->at(0);
    }
    else if (position != ExtendedBarCode::UNDEFINED) {
      if (position < pEvtColl->size()) {
        pEvt = pEvtColl->at (position);
      }
      else {
        #if 0
        MsgStream log (Athena::getMessageSvc(), "HepMcParticleLink");
        log << MSG::WARNING << "cptr: position = " << position << ", McEventCollection size = "<< pEvtColl->size() << endmsg;
        #endif
        return nullptr;
      }
    }
    else {
      pEvt = pEvtColl->find (event_number);
    }
 
    if (nullptr != pEvt) {
      // Be sure to update m_extBarcode before m_ptrs;
      // otherwise, the logic in eventIndex() won't work correctly.
      if (position != ExtendedBarCode::UNDEFINED) {
        m_extBarcode.makeIndex (pEvt->event_number(), position);
      }
      if (event_number == 0) {
        m_extBarcode.makeIndex (pEvt->event_number(), position);
      }
      if ( !m_extBarcode.linkIsNull() ) { // Check that either the ID or Barcode is non-zero or undefined
        barcode_type particle_id, particle_barcode;
        m_extBarcode.uniqueID (particle_id, particle_barcode);
        if (particle_id == ExtendedBarCode::UNDEFINEDBC) {
          // barcode to GenParticle
          const HepMC::ConstGenParticlePtr p = HepMC::barcode_to_particle(pEvt,int(particle_barcode));
          if (p) {
            int genParticleID = HepMC::uniqueID(p);
            if (genParticleID > -1) {
              particle_id = static_cast<barcode_type>(genParticleID);
              m_extBarcode.makeID (particle_id, particle_barcode);
            }
            m_ptr.set (p);
            return p;
          }
        }
        else {
          // id to GenParticle
          const auto &particles = pEvt->particles();
          if (particle_id-1 < particles.size()) {
            const HepMC::ConstGenParticlePtr p = particles[particle_id-1];
            if (p) {
              m_ptr.set (p);
              return p;
            }
          }
        }
      }
    } else {
      MsgStream log (Athena::getMessageSvc(), "HepMcParticleLink");
      if (position != ExtendedBarCode::UNDEFINED) {
        log << MSG::WARNING
            << "cptr: Mc Truth not stored for event at " << position
            << endmsg;
      } else {
        log << MSG::WARNING
            << "cptr: Mc Truth not stored for event with event number " << event_number
            << endmsg;
      }
    }
  } else {
    MsgStream log (Athena::getMessageSvc(), "HepMcParticleLink");
    log << MSG::WARNING << "cptr: McEventCollection not found" << endmsg;
  }
  return nullptr;
}

eventIndex()

HepMcParticleLink::index_type HepMcParticleLink::eventIndex

(

)

const

Return the event number of the referenced GenEvent.

0 means the first GenEvent in the collection.

Definition at line 338 of file HepMcParticleLink.cxx.

{
  // dummy link
  if (!m_ptr.isValid() && !m_store) {
    return ExtendedBarCode::UNDEFINED;
  }
 
  index_type event_number, event_position;
  m_extBarcode.eventIndex (event_number, event_position);
  if (event_number == ExtendedBarCode::UNDEFINED) {
    const HepMC::GenEvent* pEvt{};
    IProxyDict* sg_nc ATLAS_THREAD_SAFE = m_store;
    if (const McEventCollection* coll = retrieveMcEventCollection (sg_nc)) {
      if (event_position < coll->size()) {
        pEvt = coll->at (event_position);
      }
      if (pEvt) {
        const int genEventNumber = pEvt->event_number();
        // Be sure to update m_extBarcode before m_ptr.
        // Otherwise, if two threads run this method simultaneously,
        // one thread could see event_number == UNDEFINED, but where m_ptr
        // is already updated so we get nullptr back for sg.
        if (genEventNumber > -1) {
          event_number = static_cast<index_type>(genEventNumber);
          m_extBarcode.makeIndex (event_number, event_position);
          return event_number;
        }
        if (barcode() != 0) {
          HepMC::ConstGenParticlePtr pp = HepMC::barcode_to_particle(pEvt, barcode());
          if (pp) {
            m_ptr.set (pp);
          }
        }
      }
    }
  }
  // Don't trip the assertion for a null link.
  if ( m_extBarcode.linkIsNull() )
    {
      return (event_number != ExtendedBarCode::UNDEFINED) ? event_number : 0;
    }
  // Attempt to find the GenParticle
  cptr();
  // Check if event_number is valid once more
  m_extBarcode.eventIndex (event_number, event_position);
  assert (event_number != ExtendedBarCode::UNDEFINED);
  return event_number;
}

find_proxy()

SG::DataProxy * HepMcParticleLink::find_proxy ( IProxyDict * sg )

staticprivate

Find the proxy for the target event collection.

Parameters

sg	Target event store. May return nullptr if the collection is not found.

Definition at line 532 of file HepMcParticleLink.cxx.

{
  const CLID clid = ClassID_traits<McEventCollection>::ID();
  unsigned int hint_orig = s_hint.load(std::memory_order_relaxed);
  if (hint_orig >= std::size (s_keys)) hint_orig = 0;
  unsigned int hint = hint_orig;
 
  // Cache key -> sgkey translation.
  using sgkey_array_t = std::array<SG::sgkey_t, std::size (s_keys)>;
  static const sgkey_array_t s_sgkeys =
    [&]() {
      sgkey_array_t a;
      for (size_t i = 0; i < std::size (s_keys); ++i)
        a[i] = sg->stringToKey (s_keys[i], clid);
      return a;
    }();
 
  do {
    SG::DataProxy* proxy = sg->proxy (clid, s_keys[hint]);
    if (!proxy) {
      // try with input renamng.
      SG::DataProxyHolder holder;
      holder.toTransient (s_sgkeys[hint], sg, true);
      proxy = holder.proxy();
    }
    if (proxy) {
      if (hint != s_hint.load(std::memory_order_relaxed)) {
        s_hint.store(hint, std::memory_order_relaxed);
      }
      static std::once_flag log_flag;
      std::call_once(log_flag, [hint]() {
        MsgStream log (Athena::getMessageSvc(), "HepMcParticleLink");
        log << MSG::INFO << "find_proxy: Using " << s_keys[hint]
            << " as McEventCollection key for this job " << endmsg;
      });
      return proxy;
    }
    ++hint;
    if (hint >= std::size (s_keys)) hint = 0;
  } while (hint != hint_orig);
 
  MsgStream log (Athena::getMessageSvc(), "HepMcParticleLink");
  static std::atomic<unsigned long> msgCount {0};
  unsigned int count = ++msgCount;
  if (count <= CPTRMAXMSGCOUNT) {
    log << MSG::WARNING << "find_proxy: No Valid MC event Collection found "
        <<   endmsg;
  }
  if (count == CPTRMAXMSGCOUNT) {
    log << MSG::WARNING <<"find_proxy: suppressing further messages about valid MC event Collection. Use \n"
        << "  msgSvc.setVerbose += [HepMcParticleLink]\n"
        << "to see all messages" << endmsg;
  }
  if (count > CPTRMAXMSGCOUNT) {
    log << MSG::VERBOSE << "find_proxy: No Valid MC event Collection found "
        << endmsg;
  }
  return nullptr;
}

getEventNumberAtPosition() [1/2]

int HepMcParticleLink::getEventNumberAtPosition ( index_type position, const EventContext & ctx )

static

Return the event number of the GenEvent at the specified position in the McEventCollection.

Parameters

position	in the McEventCollection
sg	Target event store. Returns -999 when position is larger than the McEventCollection size

Definition at line 468 of file HepMcParticleLink.cxx.

{
  return getEventNumberAtPosition (position, Atlas::proxyDictFromEventContext (ctx));
}

getEventNumberAtPosition() [2/2]

int HepMcParticleLink::getEventNumberAtPosition ( index_type position, IProxyDict * sg )

static

Return the event number of the GenEvent at the specified position in the McEventCollection.

Parameters

position	in the McEventCollection
sg	Target event store. Returns -999 when position is larger than the McEventCollection size

Definition at line 449 of file HepMcParticleLink.cxx.

{
  if (const McEventCollection* coll = retrieveMcEventCollection (sg)) {
    if (position < coll->size()) {
      return coll->at (position)->event_number();
    }
  }
#if 0
  MsgStream log (Athena::getMessageSvc(), "HepMcParticleLink");
  log << MSG::WARNING << "getEventNumberAtPosition: position = " << position << ", McEventCollection size = "<< coll->size() << endmsg;
#endif
  return -999;
}

getEventPositionInCollection() [1/3]

HepMcParticleLink::index_type HepMcParticleLink::getEventPositionInCollection

(

const EventContext &

ctx

)

const

Return the position in the McEventCollection of the GenEvent pointed to by this HepMcParticleLink.

Return the position in the McEventCollection of the (first) GenEvent with a given event number.

Parameters

sg	Target event context. FIXME - need to be able to flag when no event with the appropriate event_number was found.

Definition at line 414 of file HepMcParticleLink.cxx.

{
  IProxyDict* sg = Atlas::proxyDictFromEventContext (ctx);
  return getEventPositionInCollection (sg);
}

getEventPositionInCollection() [2/3]

std::vector< HepMcParticleLink::index_type > HepMcParticleLink::getEventPositionInCollection ( index_type index, IProxyDict * sg )

static

Return a vector of the positions in the McEventCollection of the GenEvent(s) with a given event number.

Return the position in the McEventCollection of the (first) GenEvent with a given event number.

Parameters

index	the event number of the required GenEvent
sg	Target event store. Returns a vector containing only ExtendedBarCode::UNDEFINED FIXME when no event with the appropriate event_number was found. (Multiple entries in the vector is technically a bug, but can't be fixed until the HepMC3 migration.)

Definition at line 426 of file HepMcParticleLink.cxx.

{
  std::vector<index_type> positions; positions.reserve(1);
  const int int_event_number = static_cast<int>(event_number);
  if (const McEventCollection* coll = retrieveMcEventCollection (sg)) {
    size_t sz = coll->size();
    for (size_t i = 0; i < sz; i++) {
      if ((*coll)[i]->event_number() == int_event_number) {
        positions.push_back(i);
      }
    }
  }
  if (positions.empty() ) {
    positions.push_back(ExtendedBarCode::UNDEFINED);
  }
  return positions;
}

getEventPositionInCollection() [3/3]

HepMcParticleLink::index_type HepMcParticleLink::getEventPositionInCollection

(

IProxyDict *

sg

)

const

Return the position in the McEventCollection of the GenEvent pointed to by this HepMcParticleLink.

Return the position in the McEventCollection of the (first) GenEvent with a given event number.

Parameters

sg	Target event store. FIXME - need to be able to flag when no event with the appropriate event_number was found.

Definition at line 393 of file HepMcParticleLink.cxx.

{
  index_type event_number, position;
  m_extBarcode.eventIndex (event_number, position);
  if (position != ExtendedBarCode::UNDEFINED) {
    return position;
  }
  if (event_number == 0) {
    return 0;
  }
 
  std::vector<index_type> positions = getEventPositionInCollection(event_number, sg);
  return positions[0];
}

getLastEventCollectionName()

std::string HepMcParticleLink::getLastEventCollectionName ( )

staticprivate

Return the most recent SG key used for a particular collection type.

Definition at line 596 of file HepMcParticleLink.cxx.

{
  static const std::string unset =  "CollectionNotSet";
  unsigned idx = s_hint;
  if (idx < std::size (s_keys)) {
    return s_keys[idx];
  }
  return unset;
}

getRedirectedLink()

HepMcParticleLink HepMcParticleLink::getRedirectedLink ( const HepMcParticleLink & particleLink, uint32_t eventIndex, const EventContext & ctx )

static

Return a HepMcParticleLink pointing at the same particle, but in a different GenEvent.

Parameters

particleLink	the current HepMcParticleLink
eventIndex	the event number (unless zero) of the GenEvent which the redirected HepMcParticleLink should point at

Definition at line 481 of file HepMcParticleLink.cxx.

{
  const HepMcParticleLink::PositionFlag idxFlag =
    (eventIndex==0) ? HepMcParticleLink::IS_POSITION: HepMcParticleLink::IS_EVENTNUM;
  // Support reading in legacy barcode-based persistent EDM for now
  const int uniqueID =
    (particleLink.barcode() != 0) ? particleLink.barcode() : particleLink.id();
  const HepMcParticleLink::UniqueIDFlag uidFlag =
    (particleLink.barcode() != 0) ? HepMcParticleLink::IS_BARCODE : HepMcParticleLink::IS_ID;
  HepMcParticleLink redirectedLink(uniqueID, eventIndex, idxFlag, uidFlag, ctx);
  redirectedLink.setTruthSuppressionType(particleLink.getTruthSuppressionType());
  return redirectedLink;
}

getTruthSuppressionType()

EBC_SUPPRESSED_TRUTH HepMcParticleLink::getTruthSuppressionType

(

)

const

Return whether the truth particle has been suppressed, as an enum.

getTruthSuppressionTypeAsChar()

char HepMcParticleLink::getTruthSuppressionTypeAsChar

(

)

const

Return whether the truth particle has been suppressed, as a char ('a'..'b').

id()

int HepMcParticleLink::id

(

)

const

Return the id of the target particle.

Return the id of the referenced GenParticle.

0 for a null link.

Definition at line 284 of file HepMcParticleLink.cxx.

{
  // if m_BC is zero (delta rays), then just return that same for barcode and id
  if (m_extBarcode.uid()) {
    // dummy link
    if (!m_ptr.isValid() && !m_store) {
      return 0; // TODO Decide if this is a good default - constant from MagicNumbers.h instead?
    }
 
    barcode_type particle_id, particle_barcode;
    m_extBarcode.uniqueID (particle_id, particle_barcode);
    if (particle_id == ExtendedBarCode::UNDEFINEDBC) {
      (void) cptr(); // FIXME be careful to avoid an infinite loop of calls here
      m_extBarcode.uniqueID (particle_id, particle_barcode);
    }
    if (particle_id != ExtendedBarCode::UNDEFINEDBC) {
      return particle_id;
    }
  }
  return 0;
}

isValid()

bool HepMcParticleLink::isValid

(

)

const

Validity check.

Dereference and check for null.

linkIsNull()

bool HepMcParticleLink::linkIsNull

(

)

const

return true if neither barcode nor id are valid

Definition at line 170 of file HepMcParticleLink.cxx.

                                         {
  return m_extBarcode.linkIsNull();
}

operator bool()

HepMcParticleLink::operator bool

(

)

const

Validity check.

Dereference and check for null.

operator HepMC::ConstGenParticlePtr()

HepMcParticleLink::operator HepMC::ConstGenParticlePtr

(

)

const

Dereference.

operator!()

bool HepMcParticleLink::operator!

(

)

const

Validity check.

Dereference and check for null.

operator!=()

bool HepMcParticleLink::operator!=

(

const HepMcParticleLink &

rhs

)

const

Inequality comparison.

operator*()

const HepMC::GenParticle & HepMcParticleLink::operator*

(

)

const

Dereference.

operator->()

HepMC::ConstGenParticlePtr HepMcParticleLink::operator->

(

)

const

Dereference.

operator<()

bool HepMcParticleLink::operator<

(

const HepMcParticleLink &

rhs

)

const

Ordering comparison.

operator=() [1/2]

HepMcParticleLink & HepMcParticleLink::operator= ( const HepMcParticleLink & rhs )

default

Assignment.

operator=() [2/2]

HepMcParticleLink & HepMcParticleLink::operator= ( HepMcParticleLink && rhs )

default

Move Assignment.

operator==()

bool HepMcParticleLink::operator==

(

const HepMcParticleLink &

rhs

)

const

Equality comparison.

retrieveMcEventCollection()

const McEventCollection * HepMcParticleLink::retrieveMcEventCollection ( IProxyDict * sg )

staticprivate

Look up the event collection we're targeting.

Parameters

sg	Target event store. May return nullptr if the collection is not found.

Definition at line 513 of file HepMcParticleLink.cxx.

{
  const McEventCollection* pEvtColl = nullptr;
  SG::DataProxy* proxy = find_proxy (sg);
  if (proxy) {
    pEvtColl = SG::DataProxy_cast<McEventCollection> (proxy);
    if (!pEvtColl) {
      MsgStream log (Athena::getMessageSvc(), "HepMcParticleLink");
      log << MSG::WARNING << "cptr: McEventCollection not found" << endmsg;
    }
  }
  return pEvtColl;
}

scptr()

HepMC::ConstGenParticlePtr HepMcParticleLink::scptr ( ) const

inline

Dereference/smart pointer.

Definition at line 491 of file HepMcParticleLink.h.

{ return cptr(); }

setExtendedBarCode()

void HepMcParticleLink::setExtendedBarCode

(

const ExtendedBarCode &

extBarcode

)

Alter the persistent part of the link.

Definition at line 499 of file HepMcParticleLink.cxx.

{
  m_extBarcode = extBarcode;
  m_store = Atlas::proxyDictFromEventContext();
  m_ptr.reset();
}

setTruthSuppressionType()

void HepMcParticleLink::setTruthSuppressionType

(

EBC_SUPPRESSED_TRUTH

truthSupp

)

Return whether the truth particle has been suppressed.

Friends And Related Symbol Documentation

operator<< [1/2]

MsgStream & operator<< ( MsgStream & os, const HepMcParticleLink & link )

friend

Output operator.

Parameters

os	MsgStream to which to output.
link	Link to dump.

Definition at line 625 of file HepMcParticleLink.cxx.

{
  link.m_extBarcode.print(os);
  return os;
}

operator<< [2/2]

std::ostream & operator<< ( std::ostream & os, const HepMcParticleLink & link )

friend

Output operator.

Parameters

os	Stream to which to output.
link	Link to dump.

Definition at line 612 of file HepMcParticleLink.cxx.

{
  link.m_extBarcode.print(os);
  return os;
}

Member Data Documentation

m_extBarcode

ExtendedBarCode HepMcParticleLink::m_extBarcode

private

Persistent part: barcode and location of target GenEvent.

Definition at line 699 of file HepMcParticleLink.h.

m_ptr

ATH_NO_UNIQUE_ADDRESS CxxUtils::CachedValue<HepMC::ConstGenParticlePtr> HepMcParticleLink::m_ptr

private

Transient part. Pointer to the particle.

Definition at line 695 of file HepMcParticleLink.h.

m_store

IProxyDict* HepMcParticleLink::m_store

private

Pointer to the store containing the event.

Definition at line 687 of file HepMcParticleLink.h.

---

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

• HepMcParticleLink.h
• HepMcParticleLink.cxx