Hit pattern of CDC hits within a track. More...

#include <HitPatternCDC.h>

Public Member Functions
	HitPatternCDC ()
	Create empty pattern.

	HitPatternCDC (ULong64_t initValue)
	Initialize the pattern with an integer.

ULong64_t	getInteger () const
	Getter for underlying integer type.

unsigned short	getNHits () const
	Get the total Number of CDC hits in the fit.

void	setNHits (unsigned short nHits)
	Sets the 8 MSBs to the total number of hits in the CDC.

void	setLayer (const unsigned short layer)
	Set bit corresponding to layer to true.

void	resetLayer (const unsigned short layer)
	Set bit corresponding to layer to false.

bool	hasLayer (const unsigned short layer) const
	Getter for single layer.

short	getFirstLayer () const
	Returns the index of the first layer with a hit.

short	getLastLayer () const
	Returns the index of the last layer with a hit.

bool	hasSLayer (const unsigned short sLayer) const
	Getter for super-layer match.

void	resetSLayer (const unsigned short sLayer)
	Reset complete superLayer, e.g.

std::bitset< 64 >	getSLayerPattern (const unsigned short sLayer)
	Get the bit pattern in a specific super layer.

unsigned short	getSLayerNHits (const unsigned short sLayer) const
	Getter for the number of hits in one super-layer.

unsigned short	getLongestContRunInSL (const unsigned short sLayer) const
	Getter for longest run of consecutive layers with hits within the given Super-layer.

bool	hasAxialLayer () const
	True, if at least one axial layer is true.

bool	hasStereoLayer () const
	True, if at least one axial layer is true.

std::string	__str__ () const
	String for printing in python.

Private Member Functions
std::bitset< 64 >	getBitSet () const
	Getter for underlying bit set.

void	resetPattern ()
	Reset the complete hit pattern.

Private Attributes
std::bitset< 64 >	m_pattern
	Saves the actual pattern.

Static Private Attributes
static const std::bitset< 64 >	s_sLayerMasks [9]
	Masks to zero out all bits from other layers.

static const std::bitset< 64 >	s_infoLayerMask = infoLayerCDC
	Mask to zero out all bits from other layers.

static const std::map< unsigned short, std::pair< unsigned short, unsigned short > >	s_superLayerIndices
	Holds the indices for super layer access.

Friends
class	HitPatternCDCTest_settersNGetters_Test

class	HitPatternCDCTest_getFirstLastLayer_Test

Detailed Description

Hit pattern of CDC hits within a track.

The pattern is stored using a std::bitset. This allows to use the STL, which is very efficiently programmed.

For each layer there is one bit. The layer counting is from 0 to 55. Super-layer information is generated on demand. The super-layer counting goes from 0 to 8.

The numbering scheme just in this class is equivalent to the one defined in the note BELLE2-NOTE-TE-2015-022: https://docs.belle2.org/record/256

See also: HitPatternVXD

Definition at line 35 of file HitPatternCDC.h.

Constructor & Destructor Documentation

◆ HitPatternCDC() [1/2]

HitPatternCDC ( )

inline

Create empty pattern.

Definition at line 41 of file HitPatternCDC.h.

41: m_pattern(0) {}

Belle2::HitPatternCDC::m_pattern

std::bitset< 64 > m_pattern

Saves the actual pattern.

Definition: HitPatternCDC.h:158

◆ HitPatternCDC() [2/2]

HitPatternCDC ( ULong64_t initValue )

inlineexplicit

Initialize the pattern with an integer.

Definition at line 44 of file HitPatternCDC.h.

44: m_pattern(initValue) {}

Member Function Documentation

◆ str()

std::string __str__ ( ) const

String for printing in python.

Definition at line 169 of file HitPatternCDC.cc.

{
  return m_pattern.to_string();
}

◆ getBitSet()

std::bitset< 64 > getBitSet ( ) const

inlineprivate

Getter for underlying bit set.

Just for testing.

Definition at line 166 of file HitPatternCDC.h.

166{ return m_pattern; }

◆ getFirstLayer()

short getFirstLayer ( ) const

Returns the index of the first layer with a hit.

If there is no hit in the whole pattern, -1 is returned.

Returns: Index of last layer.

Definition at line 96 of file HitPatternCDC.cc.

{
  for (unsigned int i = 0; i < m_pattern.size(); ++i) {
    if ((m_pattern & ~s_infoLayerMask).test(i)) return i;
  }
  return -1;
}

◆ getInteger()

ULong64_t getInteger ( ) const

Getter for underlying integer type.

Definition at line 69 of file HitPatternCDC.cc.

{
  if constexpr(sizeof(unsigned long) >= 8) {
    return m_pattern.to_ulong();
  } else {
    return m_pattern.to_ullong();
  }
}

◆ getLastLayer()

short getLastLayer ( ) const

Returns the index of the last layer with a hit.

If there is no hit in the whole pattern, -1 is returned.

Returns: Index of last layer.

Definition at line 104 of file HitPatternCDC.cc.

{
  // m_pattern.size()-8 because the first 8 bits are not pattern
  for (unsigned int i = m_pattern.size() - 8; i > 0; --i) {
    // -1 because of the index couting...
    if ((m_pattern & ~s_infoLayerMask).test(i - 1)) return i - 1;
  }
  return -1;
}

◆ getLongestContRunInSL()

unsigned short getLongestContRunInSL ( const unsigned short sLayer ) const

Getter for longest run of consecutive layers with hits within the given Super-layer.

Parameters

sLayer Super-layer index.

Returns: Length of longest run.

Definition at line 139 of file HitPatternCDC.cc.

{
  B2ASSERT("Super layer outof range.", sLayer <= 8);
  unsigned short max = 0;
  unsigned short counter = 0;
  std::pair<unsigned short, unsigned short> indices = s_superLayerIndices.at(sLayer);
  for (unsigned short i = indices.first; i <= indices.second; ++i) {
    counter += m_pattern[i];
    if (m_pattern[i] == 0) {
      if (counter > max) {
        max = counter;
      }
      counter = 0;
    }
  }
  return std::max(max, counter);
}

◆ getNHits()

unsigned short getNHits ( ) const

Get the total Number of CDC hits in the fit.

Nota Bene: The maximum value returned here is 255. This is because only 8 bits are available to store the information. If the track had more than 255 hits, e.g. because it was a curler, the returned value may be to small.

Returns: Number of hits in the CDC.

Definition at line 47 of file HitPatternCDC.cc.

{
  // Shift the 8 MSBs to the right and return their value as integer.
  return static_cast<unsigned short int>((m_pattern >> 56).to_ulong());
}

◆ getSLayerNHits()

unsigned short getSLayerNHits ( const unsigned short sLayer ) const

Getter for the number of hits in one super-layer.

Nota Bene: As only a bitwise information is available if a layer is hit, under-counting is possible if in at least one layer more than one wire is hit.

Parameters

sLayer Super-layer index.

Returns: Number of hits in super-layer.

Definition at line 133 of file HitPatternCDC.cc.

{
  B2ASSERT("Super layer outof range.", sLayer <= 8);
  return static_cast<unsigned short>((m_pattern & s_sLayerMasks[sLayer]).count());
}

◆ getSLayerPattern()

std::bitset< 64 > getSLayerPattern ( const unsigned short sLayer )

Get the bit pattern in a specific super layer.

Parameters

sLayer Super-layer index.

Returns: Super-layer bit pattern.

Definition at line 128 of file HitPatternCDC.cc.

{
  return m_pattern & s_sLayerMasks[sLayer];
}

◆ hasAxialLayer()

bool hasAxialLayer ( ) const

True, if at least one axial layer is true.

Definition at line 157 of file HitPatternCDC.cc.

{
  return ((s_sLayerMasks[0] | s_sLayerMasks[2] | s_sLayerMasks[4] | s_sLayerMasks[6] | s_sLayerMasks[8])
          & m_pattern).any();
}

◆ hasLayer()

bool hasLayer ( const unsigned short layer ) const

Getter for single layer.

Parameters

layer Layer index.

Returns: Boolean if layer is hit or not.

Definition at line 90 of file HitPatternCDC.cc.

{
  B2ASSERT("Layer is out of range.", layer <= 55);
  return m_pattern[layer];
}

◆ hasSLayer()

bool hasSLayer ( const unsigned short sLayer ) const

Getter for super-layer match.

Parameters

sLayer super-layer index.

Definition at line 114 of file HitPatternCDC.cc.

{
  B2ASSERT("Super layer outof range.", sLayer <= 8);
  return ((m_pattern & s_sLayerMasks[sLayer]).any());
}

◆ hasStereoLayer()

bool hasStereoLayer ( ) const

True, if at least one axial layer is true.

Definition at line 163 of file HitPatternCDC.cc.

{
  return ((s_sLayerMasks[1] | s_sLayerMasks[3] | s_sLayerMasks[5] | s_sLayerMasks[7])
          & m_pattern).any();
}

◆ resetLayer()

void resetLayer ( const unsigned short layer )

Set bit corresponding to layer to false.

This function may throw an out-of-range exception.

Parameters

layer Layer index.

Definition at line 84 of file HitPatternCDC.cc.

{
  B2ASSERT("Layer is out of range.", layer <= 55);
  m_pattern.reset(layer);
}

◆ resetPattern()

void resetPattern ( )

inlineprivate

Reset the complete hit pattern.

Just for testing.

Definition at line 169 of file HitPatternCDC.h.

169{ m_pattern.reset(); }

◆ resetSLayer()

void resetSLayer ( const unsigned short sLayer )

Reset complete superLayer, e.g.

because segment shouldn't belong to that track.

Parameters

sLayer Super-layer index.

Definition at line 120 of file HitPatternCDC.cc.

{
  B2ASSERT("Super layer outof range.", sLayer <= 8);
  for (unsigned short int ii = 0; ii < m_pattern.size(); ++ii) {
    if ((s_sLayerMasks[sLayer])[ii]) {resetLayer(ii);}
  }
}

◆ setLayer()

void setLayer ( const unsigned short layer )

Set bit corresponding to layer to true.

This function may throw an out-of-range exception.

Parameters

layer Layer index.

Definition at line 78 of file HitPatternCDC.cc.

{
  B2ASSERT("Layer is out of range.", layer <= 55);
  m_pattern.set(layer);
}

◆ setNHits()

void setNHits ( unsigned short nHits )

Sets the 8 MSBs to the total number of hits in the CDC.

Nota Bene: If the whole track has more than 255 hits, e.g. because it is a curler, the value is set to 255.

Parameters

nHits Number of hits in the CDC.

Definition at line 53 of file HitPatternCDC.cc.

{
  if (nHits > 256) {
    // Maximum with 8 available bits
    nHits = 255;
  }
  // Reset the 8 MSBs to zero.
  m_pattern = m_pattern & ~s_infoLayerMask;
  // Set the total number of hits as the 8 MSBs
  std::bitset<64> numberOfHits(nHits);
  numberOfHits <<= 56;
  // Set the 8 MSBs to the total number of hits.
  // The 8 MSBs have to be zero, otherwise this breaks.
  m_pattern = numberOfHits | m_pattern;
}

Friends And Related Function Documentation

◆ HitPatternCDCTest_getFirstLastLayer_Test

friend class HitPatternCDCTest_getFirstLastLayer_Test

friend

Definition at line 37 of file HitPatternCDC.h.

◆ HitPatternCDCTest_settersNGetters_Test

friend class HitPatternCDCTest_settersNGetters_Test

friend

Definition at line 36 of file HitPatternCDC.h.

Member Data Documentation

◆ m_pattern

std::bitset<64> m_pattern

private

Saves the actual pattern.

Definition at line 158 of file HitPatternCDC.h.

◆ s_infoLayerMask

const std::bitset< 64 > s_infoLayerMask = infoLayerCDC

staticprivate

Mask to zero out all bits from other layers.

Definition at line 160 of file HitPatternCDC.h.

◆ s_sLayerMasks

const std::bitset< 64 > s_sLayerMasks

staticprivate

Initial value:

= {sLayerZer, sLayerOne, sLayerTwo, sLayerThr, sLayerFou,
                                                         sLayerFiv, sLayerSix, sLayerSev, sLayerEig
                                                        }

Masks to zero out all bits from other layers.

Definition at line 159 of file HitPatternCDC.h.

◆ s_superLayerIndices

const std::map< unsigned short, std::pair< unsigned short, unsigned short > > s_superLayerIndices

staticprivate

Initial value:

= {
  {0, std::make_pair(0, 7)},
  {1, std::make_pair(8, 13)},
  {2, std::make_pair(14, 19)},
  {3, std::make_pair(20, 25)},
  {4, std::make_pair(26, 31)},
  {5, std::make_pair(32, 37)},
  {6, std::make_pair(38, 43)},
  {7, std::make_pair(44, 49)},
  {8, std::make_pair(50, 55)}
}

Holds the indices for super layer access.

Definition at line 163 of file HitPatternCDC.h.

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

mdst/dataobjects/include/HitPatternCDC.h
mdst/dataobjects/src/HitPatternCDC.cc

Public Member Functions

Private Member Functions

Private Attributes

Static Private Attributes

Friends

Detailed Description

Constructor & Destructor Documentation

◆ HitPatternCDC() [1/2]

◆ HitPatternCDC() [2/2]

Member Function Documentation

◆ __str__()

◆ getBitSet()

◆ getFirstLayer()

◆ getInteger()

◆ getLastLayer()

◆ getLongestContRunInSL()

◆ getNHits()

◆ getSLayerNHits()

◆ getSLayerPattern()

◆ hasAxialLayer()

◆ hasLayer()

◆ hasSLayer()

◆ hasStereoLayer()

◆ resetLayer()

◆ resetPattern()

◆ resetSLayer()

◆ setLayer()

◆ setNHits()

Friends And Related Function Documentation

◆ HitPatternCDCTest_getFirstLastLayer_Test

◆ HitPatternCDCTest_settersNGetters_Test

Member Data Documentation

◆ m_pattern

◆ s_infoLayerMask

◆ s_sLayerMasks

◆ s_superLayerIndices

◆ str()