RooCruijff.cxx

#include "RooCruijff.h"
#include "Riostream.h" 

#include "RooAbsReal.h" 
#include "RooAbsCategory.h" 
#include <math.h> 
#include "TMath.h" 


ClassImp(RooCruijff)

RooCruijff::RooCruijff(const char *name, const char *title,
                       RooAbsReal& _x, RooAbsReal& _mean,
                       RooAbsReal& _sigmaL, RooAbsReal& _sigmaR,
                       RooAbsReal& _alphaL, RooAbsReal& _alphaR
                      ):
	RooAbsPdf(name, title),
	x("x", "Observable", this, _x),
	mean("mean", "Mean", this, _mean),
	sigmaL("sigmaL", "sigmaL", this, _sigmaL),
	sigmaR("sigmaR", "sigmaR", this, _sigmaR),
	alphaL("alphaL", "alphaL", this, _alphaL),
	alphaR("alphaR", "alphaR", this, _alphaR)
{


}

RooCruijff::RooCruijff(const RooCruijff& other, const char *name):
	RooAbsPdf(other, name),
	x("x", this, other.x),
	mean("mean", this, other.mean),
	sigmaL("sigmaL", this, other.sigmaL),
	sigmaR("sigmaR", this, other.sigmaR),
	alphaL("alphaL", this, other.alphaL),
	alphaR("alphaR", this, other.alphaR)
{

}


Double_t RooCruijff::evaluate() const
{

	Double_t sigma, alpha;
	if(x < mean) {
		sigma = sigmaL;
		alpha = alphaL;
	} else {
		sigma = sigmaR;
		alpha = alphaR;
	}

	Double_t delta_x = x - mean;
	Double_t delta_x2 = delta_x * delta_x;

	return exp(- delta_x2 / (2 * sigma * sigma + alpha * delta_x2));
}