Detailed Description

template<unsigned int PolyDegree>
class KVImpactParameters::rogly_fitting_function< PolyDegree >

Exponential function relating mean value of observable to centrality.

Template Parameters

PolyDegree The degree of the polynomial, \(N\)

This implements the function

\[ k(c_b) = k_0 \exp{\left(-\sum_{i=1}^{N} a_i c_b^i\right)} \]

from Rogly et al., Phys. Rev. C 98, 024902(2018), describing the centrality dependence of the mean value of an observable which decreases monotonically with impact parameter.

Definition at line 27 of file rogly_fitting_function.h.

#include <rogly_fitting_function.h>

Public Member Functions
	rogly_fitting_function ()

	rogly_fitting_function (const rogly_fitting_function &prev_fit)

	rogly_fitting_function (std::initializer_list< double > params)

void	backup_params ()

void	fill_array_from_params (double *p) const

void	fill_params_from_array (double *p)

double	k_cb (double cb) const

double	meanX (double cb) const

void	normalise_shape_function ()

constexpr int	npar () const

void	print_fit_params () const

double	redVar (double) const

void	restore_params ()

void	set_initial_parameters (TH1 *h, TF1 &f)

void	set_par_names (TF1 &f) const

Private Attributes
ipde_fit_parameter	kmax
	maximum of mean value for \(b=0\)

std::vector< ipde_fit_parameter >	poly_param
	polynomial coefficients

ipde_fit_parameter	theta_p
	fluctuation parameter \(\theta\)

Constructor & Destructor Documentation

◆ rogly_fitting_function() [1/3]

template<unsigned int PolyDegree>

KVImpactParameters::rogly_fitting_function< PolyDegree >::rogly_fitting_function ( )

inline

Definition at line 33 of file rogly_fitting_function.h.

◆ rogly_fitting_function() [2/3]

template<unsigned int PolyDegree>

KVImpactParameters::rogly_fitting_function< PolyDegree >::rogly_fitting_function ( const rogly_fitting_function< PolyDegree > & prev_fit )

inline

Definition at line 36 of file rogly_fitting_function.h.

◆ rogly_fitting_function() [3/3]

template<unsigned int PolyDegree>

KVImpactParameters::rogly_fitting_function< PolyDegree >::rogly_fitting_function ( std::initializer_list< double > params )

inline

Constructor with initializer list containing (in order): theta, kmax, PolyDegree coefficients

i.e. with PolyDegree=3 can construct with

rogly_fitting_function<3> fit_result{0.3, 25, -1.3, 0.21, -0.67}

KVImpactParameters::rogly_fitting_function

Exponential function relating mean value of observable to centrality.

Definition rogly_fitting_function.h:27

Definition at line 41 of file rogly_fitting_function.h.

Member Function Documentation

◆ backup_params()

template<unsigned int PolyDegree>

void KVImpactParameters::rogly_fitting_function< PolyDegree >::backup_params ( )

inline

Store all current values of parameters in backup

Definition at line 150 of file rogly_fitting_function.h.

◆ fill_array_from_params()

template<unsigned int PolyDegree>

void KVImpactParameters::rogly_fitting_function< PolyDegree >::fill_array_from_params ( double * p ) const

inline

Copy values of parameters into the array (interface to ROOT TF1)

Parameters

[in]	p	address of an array of size given by npar()
[in]	p[0]	\(\theta\)
[in]	p[1]	\(k_{max}\)
[in]	p[2]	\(a_1\)
[in]	p[...]	...
[in]	p[1+PolyDegree]	\(a_{PolyDegree}\)

Definition at line 92 of file rogly_fitting_function.h.

◆ fill_params_from_array()

template<unsigned int PolyDegree>

void KVImpactParameters::rogly_fitting_function< PolyDegree >::fill_params_from_array ( double * p )

inline

Set values of parameters from values in the array (interface to ROOT TF1)

Parameters

[in]	p	address of an array of size given by npar()
[in]	p[0]	\(\theta\)
[in]	p[1]	\(k_{max}\)
[in]	p[2]	\(a_1\)
[in]	p[...]	...
[in]	p[1+PolyDegree]	\(a_{PolyDegree}\)

Definition at line 79 of file rogly_fitting_function.h.

◆ k_cb()

template<unsigned int PolyDegree>

double KVImpactParameters::rogly_fitting_function< PolyDegree >::k_cb ( double cb ) const

inline

Returns: value of \(k(c_b)\) for given centrality

Parameters

[in] cb centrality

Definition at line 71 of file rogly_fitting_function.h.

◆ meanX()

template<unsigned int PolyDegree>

double KVImpactParameters::rogly_fitting_function< PolyDegree >::meanX ( double cb ) const

inline

Definition at line 175 of file rogly_fitting_function.h.

◆ normalise_shape_function()

template<unsigned int PolyDegree>

void KVImpactParameters::rogly_fitting_function< PolyDegree >::normalise_shape_function ( )

inline

Modify values of parameters so that \(k(c_b)\) varies between 1 at \(c_b=0\) to 0 at \(c_b=1\).

Todo:: Currently this just scales \(k_{max}\) to 1, the minimum at \(c_b=1\) will not be zero.

Definition at line 168 of file rogly_fitting_function.h.

◆ npar()

template<unsigned int PolyDegree>

constexpr int KVImpactParameters::rogly_fitting_function< PolyDegree >::npar ( ) const

inlineconstexpr

Returns: number of parameters for fitting function (=PolyDegree+2)

Definition at line 65 of file rogly_fitting_function.h.

◆ print_fit_params()

template<unsigned int PolyDegree>

void KVImpactParameters::rogly_fitting_function< PolyDegree >::print_fit_params ( ) const

inline

Definition at line 134 of file rogly_fitting_function.h.

◆ redVar()

template<unsigned int PolyDegree>

double KVImpactParameters::rogly_fitting_function< PolyDegree >::redVar ( double ) const

inline

Definition at line 179 of file rogly_fitting_function.h.

◆ restore_params()

template<unsigned int PolyDegree>

void KVImpactParameters::rogly_fitting_function< PolyDegree >::restore_params ( )

inline

Retore all current values of parameters from backup

Definition at line 159 of file rogly_fitting_function.h.

◆ set_initial_parameters()

template<unsigned int PolyDegree>

void KVImpactParameters::rogly_fitting_function< PolyDegree >::set_initial_parameters	(	TH1 *	h,
		TF1 &	f
	)

inline

Set initial values for parameters in TF1 object based on data in histogram h

Parameters

[in]	h	histogram with data (inclusive distribution of observable, \(P(X)\)) to be fitted
[in,out]	f	ROOT function using this implementation of \(k(c_b)\)

Definition at line 118 of file rogly_fitting_function.h.

◆ set_par_names()

template<unsigned int PolyDegree>

void KVImpactParameters::rogly_fitting_function< PolyDegree >::set_par_names ( TF1 & f ) const

inline

double theta() const { // Get value of \(\theta\) parameter return theta_p.value; }

Set name of parameters in TF1 object

Parameters

[in,out] f ROOT function using this implementation of \(k(c_b)\)

Definition at line 110 of file rogly_fitting_function.h.

Member Data Documentation

◆ kmax

template<unsigned int PolyDegree>

ipde_fit_parameter KVImpactParameters::rogly_fitting_function< PolyDegree >::kmax

private

maximum of mean value for \(b=0\)

Definition at line 29 of file rogly_fitting_function.h.

◆ poly_param

template<unsigned int PolyDegree>

std::vector<ipde_fit_parameter> KVImpactParameters::rogly_fitting_function< PolyDegree >::poly_param

private

polynomial coefficients

Definition at line 30 of file rogly_fitting_function.h.

◆ theta_p

template<unsigned int PolyDegree>

ipde_fit_parameter KVImpactParameters::rogly_fitting_function< PolyDegree >::theta_p

private

fluctuation parameter \(\theta\)

Definition at line 28 of file rogly_fitting_function.h.

Detailed Description

Public Member Functions

Private Attributes

Constructor & Destructor Documentation

◆ rogly_fitting_function() [1/3]

◆ rogly_fitting_function() [2/3]

◆ rogly_fitting_function() [3/3]

Member Function Documentation

◆ backup_params()

◆ fill_array_from_params()

◆ fill_params_from_array()

◆ k_cb()

◆ meanX()

◆ normalise_shape_function()

◆ npar()

◆ print_fit_params()

◆ redVar()

◆ restore_params()

◆ set_initial_parameters()

◆ set_par_names()

Member Data Documentation

◆ kmax

◆ poly_param

◆ theta_p