TSFunc1DErfWeightedPdf.h

/*
 * TSFunc1DErfWeightedPdf.h
 *
 *  Created on: Dec 6, 2018
 *      Author: Maciej Lewicki
 *      malewick@cern.ch
 *
 */

#ifndef TSFUNC1DERFWEIGHTEDPDF_H_
#define TSFUNC1DERFWEIGHTEDPDF_H_


#include "TSFunc1DGaussPdf.h"

/* 
 * f(x) = 
 *  = \frac{1}{\sum_l n_l}\sum_l \frac{n_l}{\sqrt{2\pi}\sigma_{i,l}}\exp{-\frac{1}{2}\left( \frac{x-x_i}{(1 \pm \delta)\sigma_{i,l}} \right)^2}
 * , where:
 * \sigma_{i,l} = \frac{\sigma_0}{\sqrt{l}} \left( \frac{x_i}{x_1} \right)^{\alpha}
 */


class TSFunc1DErfWeightedPdf: public TSFunc1DGaussPdf {


public:

    TSFunc1DErfWeightedPdf(TString name, TString title
                    ,const TSVariable& var_x, const TSParameter& mean, const TSParameter& sigma
                    ,const TSParameter& delta
                    ,std::map<int,int>& npoints );


    virtual ~TSFunc1DErfWeightedPdf();

    virtual double Evaluate() const;

    double GetDelta() const { return fDelta ? fDelta->GetValue(): 0; }

    const TSParameter *GetParamDelta() const {return fDelta;}

    void SetSpread(double spread) { fSpread = spread; }

private:

    const TSParameter *fDelta;
    std::map<int,int> fNPoints;

    double fSpread;

};

#endif /* TSFUNC1DERFWEIGHTEDPDF_H_ */