AliPhysics  ef3b16e (ef3b16e)
GraphSysErr::LinearSigmaCombiner Struct Reference
Inheritance diagram for GraphSysErr::LinearSigmaCombiner:

Public Member Functions

Double_t W (const Observation &r) const
 
Double_t StepW (Double_t guess, const Observation &r) const
 
Double_t StepOffset (Double_t, const Observation &) const
 
Double_t VarTerm (Double_t guess, const Observation &r) const
 
Wrapper_t Wrapper () const
 
- Public Member Functions inherited from GraphSysErr::Combiner
 Combiner ()
 
virtual ~Combiner ()
 
Double_t ChiTerm (Double_t guess, const Observation &r) const
 
Double_t F (Double_t guess, Double_t chi2) const
 
Double_t E (UShort_t nIter, Int_t sign, Double_t best, Double_t chi2, Double_t s)
 
Double_t X (UShort_t nIter, Double_t lowest, Double_t highest)
 
ResultCalculate (UShort_t nIter=50)
 
TF1 * MakeF (const Observation &r, Int_t j) const
 
TLine * MakeL (TF1 *f) const
 
void Draw (Option_t *option="")
 
void Clear (Option_t *option="")
 
void Add (const Observation &r)
 
void Add (Double_t x, Double_t el, Double_t eh)
 
void Print (Option_t *option="") const
 

Static Public Member Functions

static Double_t L (Double_t guess, Double_t x, Double_t el, Double_t eh)
 
static Double_t WrapL (Double_t *xp, Double_t *pp)
 

Additional Inherited Members

- Public Types inherited from GraphSysErr::Combiner
typedef Double_t(* Wrapper_t) (Double_t *, Double_t *)
 
- Public Attributes inherited from GraphSysErr::Combiner
TClonesArray fData
 
ResultfResult
 

Detailed Description

A combiner that uses a linear \(\sigma\) approximation

Definition at line 5417 of file GraphSysErr.C.

Member Function Documentation

static Double_t GraphSysErr::LinearSigmaCombiner::L ( Double_t  guess,
Double_t  x,
Double_t  el,
Double_t  eh 
)
inlinestatic

Return the likely-hood function value at \( x'\):

\[ L(x') = \left[(x'-x) / (s + s'(x'-x))\right]^2 \]

where

\[ s = 2\sigma^+\sigma^-/(\sigma^++\sigma^-) \]

\[ s' = (\sigma^+-\sigma^-)/(\sigma^++\sigma^-) \]

Parameters
guess\( x'\)
x\( x\)
el\( \sigma^-\)
eh\( \sigma^+\)
Returns

Definition at line 5505 of file GraphSysErr.C.

Double_t GraphSysErr::LinearSigmaCombiner::StepOffset ( Double_t  ,
const Observation  
) const
inlinevirtual

Calculate the bias.

Returns
0

Implements GraphSysErr::Combiner.

Definition at line 5462 of file GraphSysErr.C.

Double_t GraphSysErr::LinearSigmaCombiner::StepW ( Double_t  guess,
const Observation r 
) const
inlinevirtual

Calculate the weight based on a guess of best \( x'\)

\[ w(x') = s / [s + s' (x' - x)]^3 \]

Parameters
guessCurrent guess \( x'\)
rObservation
Returns
\( W(x')\)

Implements GraphSysErr::Combiner.

Definition at line 5450 of file GraphSysErr.C.

Double_t GraphSysErr::LinearSigmaCombiner::VarTerm ( Double_t  guess,
const Observation r 
) const
inlinevirtual

Calculate the contribution variance to the \(\chi^2\) with the guess \(x'\).

\[ v(x') = [s + s' (x' - x)]^2 \]

Parameters
guessCurrent guess \( x'\)
rObservation
Returns
\( v(x')\)

Implements GraphSysErr::Combiner.

Definition at line 5479 of file GraphSysErr.C.

Double_t GraphSysErr::LinearSigmaCombiner::W ( const Observation r) const
inlinevirtual

Calculate the weight

\[ w = 1/2 (s + x s')^3 / s \]

Parameters
rObservation
Returns
\( W\)

Implements GraphSysErr::Combiner.

Definition at line 5430 of file GraphSysErr.C.

static Double_t GraphSysErr::LinearSigmaCombiner::WrapL ( Double_t xp,
Double_t pp 
)
inlinestatic

Wrap likely-hood function for ROOT

Parameters
xpPointer to independent variables
ppPointer to parameters
Returns
Likely-hood function evaluate at xp

Definition at line 5523 of file GraphSysErr.C.

Wrapper_t GraphSysErr::LinearSigmaCombiner::Wrapper ( ) const
inlinevirtual

Return function pointer to wrapper

Returns
Function pointer

Implements GraphSysErr::Combiner.

Definition at line 5532 of file GraphSysErr.C.


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