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LHAPDF  6.1.6
LHAPDF::AlphaSArray Class Reference

Internal storage class for alpha_s interpolation grids. More...

#include <KnotArray.h>

Public Member Functions

Construction etc.
 AlphaSArray ()
 Default constructor just for std::map insertability.
 
 AlphaSArray (const std::vector< double > &q2knots, const std::vector< double > &as)
 Constructor from Q2 knot values and alpha_s values.
 
Q2 stuff
const std::vector< double > & q2s () const
 Q2 knot vector accessor.
 
const std::vector< double > & logq2s () const
 log(Q2) knot vector accessor
 
size_t iq2below (double q2) const
 
size_t ilogq2below (double logq2) const
 
alpha_s values at Q2 points
const std::vector< double > & alphas () const
 alpha_s value accessor (const)
 
alpha_s derivatives vs (log)Q2, useful for interpolation
double ddlogq_forward (size_t i) const
 Forward derivative w.r.t. logQ2.
 
double ddlogq_backward (size_t i) const
 Backward derivative w.r.t. logQ2.
 
double ddlogq_central (size_t i) const
 Central (avg of forward and backward) derivative w.r.t. logQ2.
 

Private Member Functions

void _sync ()
 Synchronise the log(Q2) array from the Q2 one.
 

Private Attributes

std::vector< double > _q2s
 List of Q2 knots.
 
std::vector< double > _logq2s
 List of log(Q2) knots.
 
std::vector< double > _as
 List of alpha_s values across the knot array.
 

Detailed Description

Internal storage class for alpha_s interpolation grids.

Member Function Documentation

size_t LHAPDF::AlphaSArray::ilogq2below ( double  logq2) const
inline

Get the index of the closest logQ2 knot row <= logq2

If the value is >= q2_max, return i_max-1 (for polynomial spine construction)

Find the closest knot below the requested value

size_t LHAPDF::AlphaSArray::iq2below ( double  q2) const
inline

Get the index of the closest Q2 knot row <= q2

If the value is >= q2_max, return i_max-1 (for polynomial spine construction)

Find the closest knot below the requested value


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