This class holds the prior distribution for a single particle species. More...

#include <PIDPriorsTable.h>

Public Member Functions
void	setBinEdges (const std::vector< float > &binEdgesX, const std::vector< float > &binEdgesY)
	Sets the bin edges arrays.

void	setPriorsTable (const std::vector< float > &priors)
	Sets the priors table from a 2D std::vector.

void	setErrorsTable (const std::vector< float > &errors)
	Sets the priors error table from a 2D std::vector.

void	setPriorValue (float x, float y, float value)
	Sets the prior value for a single bin.

void	setErrorValue (float x, float y, float value)
	Sets the error on the prior value for a single bin.

void	setAxisLabels (const std::string &labelX, const std::string &labelY)
	Sets axes labels.

float	getPriorInBin (int iX, int iY) const
	Returns the prior probability for a given bin.

float	getErrorInBin (int iX, int iY) const
	Returns the error on prior probability for a given bin.

float	getPriorValue (float x, float y) const
	Returns the prior probability for a given value of (x,y).

float	getErrorValue (float x, float y) const
	Returns the error on the prior probability for a given value of (x,y).

std::string	getXAxisLabel () const
	Returns the X axis label.

std::string	getYAxisLabel () const
	Returns the Y axis label.

void	printPrior () const
	Prints the content of the table and the axes.

void	printError () const
	Prints the content of the error table and the axes.

Private Member Functions
bool	checkRange (const std::string &text, float val, const std::vector< float > &edges) const
	Checks if a value is within the range of an array.

short	findBin (float val, std::vector< float > array) const
	This function returns the position of a number in a sorted array of bin edges.

short	findBinFast (float val, std::vector< float > array) const
	This function returns the position of a number in a sorted array of bin edges This implementation should be more clever than the binary search implemented in findBin, but at the very end it seems to be slower.

short	findBinWithFixedWidth (float val, std::vector< float > array) const
	This function returns the position of a number in a sorted array of bin edges, assuming that the latter are equally spaced.

Private Attributes
std::vector< float >	m_binEdgesX = {}
	The array containing the bin edges for the X axis.

std::vector< float >	m_binEdgesY = {}
	The array containing the bin edges for the Y axis.

std::vector< float >	m_priors
	The matrix with the prior probabilities.

std::vector< float >	m_errors
	The matrix with the errors on the prior probabilities.

std::string	m_xAxisLabel = ""
	label of the X axis, indicating which variable is represented here

std::string	m_yAxisLabel = ""
	label of the Y axis, indicating which variable is represented here

Detailed Description

This class holds the prior distribution for a single particle species.

Its basic data members are two 2D matrices of floats (one for the probability, one for it uncertainties) plus two arrays for the bins edges. All these elements, including the matrices, are implemented as 1 dimensional vectors. The PIDPriors class that is stored in the database is basically nothing but a collection of 6 of these objects, one per particle species.

Definition at line 27 of file PIDPriorsTable.h.

Member Function Documentation

◆ checkRange()

bool checkRange	(	const std::string &	text,
		float	val,
		const std::vector< float > &	edges
	)		const

private

Checks if a value is within the range of an array.

Parameters

text	text to display in the warning message
val	the value
edges	the vector of bin edge values the val has to be found in

Returns: the position of the last edge below the input value

Definition at line 152 of file PIDPriorsTable.cc.

{
  const float& min = edges.front();
  const float& max = edges.back();
  if (val > max || val < min) {
    B2WARNING("PriorsTable: " << text  << LogVar("value", val) << LogVar("min", min) << LogVar("max", max));
    return false;
  }
  return true;
};

◆ findBin()

short findBin	(	float	val,
		std::vector< float >	array
	)		const

private

This function returns the position of a number in a sorted array of bin edges.

Parameters

val	the value
array	the std::vector the val has to be found

Returns: the position of the last edge below the input value

Definition at line 164 of file PIDPriorsTable.cc.

{
  auto it = std::lower_bound(array.cbegin(),  array.cend(), val);
  return std::distance(array.cbegin(), it) - 1;
};

◆ findBinFast()

short findBinFast	(	float	val,
		std::vector< float >	array
	)		const

private

This function returns the position of a number in a sorted array of bin edges This implementation should be more clever than the binary search implemented in findBin, but at the very end it seems to be slower.

It's kept in here just in case someone passes by and finds a way to speed it up.

Parameters

val	the value
array	the std::vector the val has to be found

Returns: the position of the last edge below the input value

Definition at line 171 of file PIDPriorsTable.cc.

{
  // This function searches for the first bin the axis which is above the
  // value. First it starts assuming the bins are equal, and then moves around
  // the array until the correct bin is found
  float averageBinSize = (array.back() - array.front()) / (array.size() - 1);
  short bin = 1 + (short)((val - array[0]) / averageBinSize);
  //adjusts forward
 
  while (bin < static_cast<short>(array.size()) && array[bin] < val) {
    bin++;
  }
  //adjusts backward
  while (bin - 1 >  0 && array[bin - 1] > val) {
    bin--;
  }
  return bin - 1;
};

◆ findBinWithFixedWidth()

short findBinWithFixedWidth	(	float	val,
		std::vector< float >	array
	)		const

private

This function returns the position of a number in a sorted array of bin edges, assuming that the latter are equally spaced.

Parameters

val	the value
array	the std::vector the val has to be found

Returns: the position of the last edge below the input value

Definition at line 191 of file PIDPriorsTable.cc.

{
  float binWidth = (array.back() - array.front()) / (array.size() - 1.);
  return (short)((val - array.back()) / binWidth);
};

◆ getErrorInBin()

float getErrorInBin	(	int	iX,
		int	iY
	)		const

inline

Returns the error on prior probability for a given bin.

If the bin is outside of the table boundaries, 0 will be returned.

Parameters

iX	bin number on the X axis
iY	bin number on the Y axis

Returns: the error on the prior probability value

Definition at line 111 of file PIDPriorsTable.h.

    {
      return m_errors[iX + (m_binEdgesX.size() - 1) * iY];
    };

◆ getErrorValue()

float getErrorValue	(	float	x,
		float	y
	)		const

Returns the error on the prior probability for a given value of (x,y).

If the bin is outside of the table boundaries, 0 will be returned.

Parameters

x	the x-value of the x coordinate
y	the y-value of the y coordinate

Returns: value the error on the prior probability value

Definition at line 89 of file PIDPriorsTable.cc.

{
  if (!checkRange("The value is out of range for the X axis", x, m_binEdgesX)
      || !checkRange("The value is out of range for the Y axis", y, m_binEdgesY)) return 0;
  auto binX = findBin(x, m_binEdgesX);
  auto binY = findBin(y, m_binEdgesY);
  return getErrorInBin(binX, binY);
};

◆ getPriorInBin()

float getPriorInBin	(	int	iX,
		int	iY
	)		const

inline

Returns the prior probability for a given bin.

If the bin is outside of the table boundaries, 0 will be returned.

Parameters

iX	bin number on the X axis
iY	bin number on the Y axis

Returns: value the prior probability value

Definition at line 99 of file PIDPriorsTable.h.

    {
      return m_priors[iX + (m_binEdgesX.size() - 1) * iY];
    };

◆ getPriorValue()

float getPriorValue	(	float	x,
		float	y
	)		const

Returns the prior probability for a given value of (x,y).

If the bin is outside of the table boundaries, 0 will be returned.

Parameters

x	the x-value of the x coordinate
y	the y-value of the y coordinate

Returns: the value the prior probability value

Definition at line 79 of file PIDPriorsTable.cc.

{
  if (!checkRange("The value is out of range for the X axis", x, m_binEdgesX)
      || !checkRange("The value is out of range for the Y axis", y, m_binEdgesY)) return 0;
  auto binX = findBin(x, m_binEdgesX);
  auto binY = findBin(y, m_binEdgesY);
  return getPriorInBin(binX, binY);
};

◆ getXAxisLabel()

std::string getXAxisLabel ( ) const

inline

Returns the X axis label.

Returns: the X axis label

Definition at line 139 of file PIDPriorsTable.h.

    {
      return m_xAxisLabel;
    };

◆ getYAxisLabel()

std::string getYAxisLabel ( ) const

inline

Returns the Y axis label.

Returns: the Y axis label

Definition at line 148 of file PIDPriorsTable.h.

    {
      return m_yAxisLabel;
    };

◆ printError()

void printError ( ) const

Prints the content of the error table and the axes.

Definition at line 125 of file PIDPriorsTable.cc.

{
  std::cout << " --- Error summary --- " << std::endl;
  std::cout << " Size :  " << m_errors.size() << " (" << m_binEdgesX.size() - 1 <<  " x  " <<   m_binEdgesY.size() - 1 << ")" <<
            std::endl;
  std::cout << " X axis:  " ;
  for (auto edge : m_binEdgesX) {
    std::cout << " "  << edge << " " ;
  }
  std::cout << " " << std::endl;
  std::cout << " Y axis ";
  for (auto edge : m_binEdgesY) {
    std::cout << " " << edge << " " ;
  }
  std::cout << " " << std::endl;
  std::cout << " Values " << std::endl;
  for (int iY = m_binEdgesY.size() - 2; iY >= 0; iY--) {
    for (int iX = 0; iX < static_cast<int>(m_binEdgesX.size() - 1); iX++) {
      std::cout << " " << getErrorInBin(iX, iY) << " ";
    }
    std::cout << " " << std::endl;
  }
  std::cout << " --- End of error summary --- " << std::endl;
};

◆ printPrior()

void printPrior ( ) const

Prints the content of the table and the axes.

Definition at line 99 of file PIDPriorsTable.cc.

{
  std::cout << " --- Prior summary --- " << std::endl;
  std::cout << " Size :  " << m_priors.size() << " (" << m_binEdgesX.size() - 1 <<  " x  " <<   m_binEdgesY.size() - 1 << ")" <<
            std::endl;
  std::cout << " X axis:  " ;
  for (auto edge : m_binEdgesX) {
    std::cout << " "  << edge << " " ;
  }
  std::cout << " " << std::endl;
  std::cout << " Y axis ";
  for (auto edge : m_binEdgesY) {
    std::cout << " " << edge << " " ;
  }
  std::cout << " " << std::endl;
  std::cout << " Values " << std::endl;
  for (int iY = m_binEdgesY.size() - 2; iY >= 0; iY--) {
    for (int iX = 0; iX < static_cast<int>(m_binEdgesX.size() - 1); iX++) {
      std::cout << " " << getPriorInBin(iX, iY) << " ";
    }
    std::cout << " " << std::endl;
  }
  std::cout << " --- End of prior summary --- " << std::endl;
};

◆ setAxisLabels()

void setAxisLabels	(	const std::string &	labelX,
		const std::string &	labelY
	)

inline

Sets axes labels.

Parameters

labelX	the label of the X axis
labelY	the label of the X axis

Definition at line 85 of file PIDPriorsTable.h.

    {
      m_xAxisLabel = labelX;
      m_yAxisLabel = labelY;
      return ;
    }

◆ setBinEdges()

void setBinEdges	(	const std::vector< float > &	binEdgesX,
		const std::vector< float > &	binEdgesY
	)

Sets the bin edges arrays.

Please notice that setting the axes will also automatically clear the tables.

Parameters

binEdgesX	the vector of bin edges for the X axis
binEdgesY	the vector of bin edges for the Y axis

Definition at line 17 of file PIDPriorsTable.cc.

{
  m_binEdgesX = binEdgesX;
  m_binEdgesY = binEdgesY;
 
  // if less than two edges are provided, assumes the maximum range for floats
  auto checkEdges = [](std::vector<float>& edges, const std::string & axis) {
    if (edges.size() < 2) {
      B2WARNING("You provided less than 2 bin edges for the " << axis <<
                " axis. This is not enough to create one bin, so one will be created with range [-FLT_MAX, +FLT_MAX]");
      edges = { -FLT_MAX, FLT_MAX};
    }
    auto prevVal = edges[0];
    for (int iBin = 1; iBin < static_cast<int>(edges.size()); iBin++) {
      auto edge = edges[iBin];
      if (prevVal >= edge)
        B2FATAL("Null or negative bin size found on the X axis. Please make sure that all the bin edges are sorted and non-equal");
      prevVal = edge;
    }
    return;
  };
 
  checkEdges(m_binEdgesX, "X");
  checkEdges(m_binEdgesY, "Y");
 
  m_priors.clear();
  m_errors.clear();
 
  m_priors.resize((m_binEdgesY.size() - 1) * (m_binEdgesX.size() - 1), 0.);
  m_errors.resize((m_binEdgesY.size() - 1) * (m_binEdgesX.size() - 1), 0.);
  return;
};

◆ setErrorsTable()

void setErrorsTable ( const std::vector< float > & errors )

inline

Sets the priors error table from a 2D std::vector.

Parameters

errors 2D std:vector of floats containing the error on the prior probability for each bin

Definition at line 55 of file PIDPriorsTable.h.

    {
      m_errors = errors;
      return;
    };

◆ setErrorValue()

void setErrorValue	(	float	x,
		float	y,
		float	value
	)

Sets the error on the prior value for a single bin.

Parameters

x	the x-value of the x coordinate
y	the y-value of the y coordinate
value	the x-value of the prior probability error associated to x and y

Definition at line 67 of file PIDPriorsTable.cc.

{
  if (!checkRange("The value is out of range for the X axis", x, m_binEdgesX)
      || !checkRange("The value is out of range for the Y axis", y, m_binEdgesY)) return ;
 
  auto binX = findBin(x, m_binEdgesX);
  auto binY = findBin(y, m_binEdgesY);
  m_errors[binX + (m_binEdgesX.size() - 1)*binY] = value;
  return ;
};

◆ setPriorsTable()

void setPriorsTable ( const std::vector< float > & priors )

inline

Sets the priors table from a 2D std::vector.

Parameters

priors 2D std:vector of floats containing the prior probability for each bin

Definition at line 44 of file PIDPriorsTable.h.

    {
      m_priors = priors;
      return;
    };

◆ setPriorValue()

void setPriorValue	(	float	x,
		float	y,
		float	value
	)

Sets the prior value for a single bin.

Parameters

x	the x-value of the x coordinate
y	the y-value of the y coordinate
value	the x-value of the prior probability associated to x and y

Definition at line 52 of file PIDPriorsTable.cc.

{
  if (!checkRange("The value is out of range for the X axis", x, m_binEdgesX)
      || !checkRange("The value is out of range for the Y axis", y, m_binEdgesY)) return;
  if (value > 1. || value < 0.) {
    B2WARNING("The value " << value  << " you are trying to set for the bin (" << x << ",  " << y <<
              ") does not look like a probability. The table will be filled, but i  will not be usable as a proper prior probability table.");
  }
  auto binX = findBin(x, m_binEdgesX);
  auto binY = findBin(y, m_binEdgesY);
  m_priors[binX + (m_binEdgesX.size() - 1)*binY] = value;
  return;
};

Member Data Documentation

◆ m_binEdgesX

std::vector<float> m_binEdgesX = {}

private

The array containing the bin edges for the X axis.

Definition at line 167 of file PIDPriorsTable.h.

◆ m_binEdgesY

std::vector<float> m_binEdgesY = {}

private

The array containing the bin edges for the Y axis.

Definition at line 168 of file PIDPriorsTable.h.

◆ m_errors

std::vector<float> m_errors

private

The matrix with the errors on the prior probabilities.

Definition at line 170 of file PIDPriorsTable.h.

◆ m_priors

std::vector<float> m_priors

private

The matrix with the prior probabilities.

Definition at line 169 of file PIDPriorsTable.h.

◆ m_xAxisLabel

std::string m_xAxisLabel = ""

private

label of the X axis, indicating which variable is represented here

Definition at line 171 of file PIDPriorsTable.h.

◆ m_yAxisLabel

std::string m_yAxisLabel = ""

private

label of the Y axis, indicating which variable is represented here

Definition at line 172 of file PIDPriorsTable.h.

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

analysis/dbobjects/include/PIDPriorsTable.h
analysis/dbobjects/src/PIDPriorsTable.cc

Public Member Functions

Private Member Functions

Private Attributes

Detailed Description

Member Function Documentation

◆ checkRange()

◆ findBin()

◆ findBinFast()

◆ findBinWithFixedWidth()

◆ getErrorInBin()

◆ getErrorValue()

◆ getPriorInBin()

◆ getPriorValue()

◆ getXAxisLabel()

◆ getYAxisLabel()

◆ printError()

◆ printPrior()

◆ setAxisLabels()

◆ setBinEdges()

◆ setErrorsTable()

◆ setErrorValue()

◆ setPriorsTable()

◆ setPriorValue()

Member Data Documentation

◆ m_binEdgesX

◆ m_binEdgesY

◆ m_errors

◆ m_priors

◆ m_xAxisLabel

◆ m_yAxisLabel