KVGausGumDistribution.cpp

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//Created by KVClassFactory on Mon Apr 20 14:02:31 2012
//Author: John Frankland,,,
 
#include "KVGausGumDistribution.h"
#include "TMath.h"
#include "Riostream.h"
 
ClassImp(KVGausGumDistribution)
 
 
 
KVGausGumDistribution::KVGausGumDistribution()
   : TF1(), fGaussComp(0), fGumbelComp(0)
{
   // default ctor
   SetLineColor(kBlack);
   SetNpx(2000);
   fkFac = 0.;
   fkGaussNor = 1. / sqrt(2 * TMath::Pi());
}
 
 
 
 
 
KVGausGumDistribution::KVGausGumDistribution(const Char_t* name, Int_t k, Double_t xmin, Double_t xmax)
   : TF1(name, this, &KVGausGumDistribution::GDk, xmin, xmax, 5,
         "KVGausGumDistribution", "GDk"), fGaussComp(0), fGumbelComp(0)
{
   // normalised sum of Gaussian distribution and Gumbel distribution of k-th rank
   // f = eta*Gauss(mean,sigma) + (1-eta)*Gumbel(a,b)
   // free parameters: gauss: (mean,sigma) gumbel: (a,b) eta
   fRank = k;
   fkFac = TMath::Power(k, k) / TMath::Factorial(k - 1);
   fkGaussNor = 1. / sqrt(2 * TMath::Pi());
   SetParName(0, "#eta");
   SetParName(1, "#mu");
   SetParName(2, "#sigma");
   SetParName(3, "#mu-a_{m}");
   SetParName(4, "b_{m}");
   SetParLimits(0, 0., 1.);
   SetParLimits(1, GetXmin(), GetXmax());
   SetParLimits(2, 0.01, 200.);
   SetParLimits(3, 0.01, GetXmax());
   SetParLimits(4, 0.01, 200.);
   SetLineColor(kBlack);
   SetNpx(2000);
 
}
 
 
 
 
 
KVGausGumDistribution::KVGausGumDistribution(const KVGausGumDistribution& obj)  : TF1()
{
   // Copy constructor
   // This ctor is used to make a copy of an existing object (for example
   // when a method returns an object), and it is always a good idea to
   // implement it.
   // If your class allocates memory in its constructor(s) then it is ESSENTIAL :-)
 
   obj.Copy(*this);
}
 
 
 
 
KVGausGumDistribution::~KVGausGumDistribution()
{
   // Destructor
   SafeDelete(fGaussComp);
   SafeDelete(fGumbelComp);
}
 
 
 
 
 
void KVGausGumDistribution::Copy(TObject& obj) const
{
   // This method copies the current state of 'this' object into 'obj'
   // You should add here any member variables, for example:
   //    (supposing a member variable KVGausGumDistribution::fToto)
   //    CastedObj.fToto = fToto;
   // or
   //    CastedObj.SetToto( GetToto() );
 
   TF1::Copy(obj);
   KVGausGumDistribution& CastedObj = (KVGausGumDistribution&)obj;
   CastedObj.fRank = fRank;
   CastedObj.fkFac = fkFac;
   CastedObj.fkGaussNor = fkGaussNor;
}
 
 
 
 
 
void KVGausGumDistribution::Paint(Option_t* option)
{
   // Draw total distribution and the two component distributions
 
   TF1::Paint(option);
   if (!fkGaussNor) fkGaussNor = 1. / sqrt(2 * TMath::Pi());
 
   if (!fGaussComp)  fGaussComp = new TF1("GaussComp", "[0]*exp(-0.5*((x-[1])/[2])**2)", GetXmin(), GetXmax());
   if (!fGumbelComp) fGumbelComp = new KVGumbelDistribution("GumbelComp", fRank, false, GetXmin(), GetXmax());
   fGaussComp->SetParameters(fkGaussNor * GetParameter(0) / GetParameter(2), GetParameter(1), GetParameter(2));
   fGumbelComp->SetParameters(GetParameter(1) - GetParameter(3), GetParameter(4), (1. - GetParameter(0)));
 
   fGaussComp->SetLineColor(kBlue);
   fGaussComp->SetLineStyle(9);
   fGaussComp->SetLineWidth(5);
   fGaussComp->SetNpx(2000);
 
   fGumbelComp->SetLineColor(kRed);
   fGumbelComp->SetLineWidth(5);
   fGumbelComp->SetNpx(2000);
 
   fGaussComp->Paint("same");
   fGumbelComp->Paint("same");
}
 
 
 
 
 
Double_t KVGausGumDistribution::GDk(Double_t* x, Double_t* p)
{
   // Evaluate normalised sum of Gaussian and Gumbel distribution of rank fRank for x
   // with parameters
   // par[0] = eta
   // par[1] = mu
   // par[2] = sigma
   // par[3] = distance between gaussian and gumbel >=0
   // par[4] = b
 
   if (p[4] == 0) return 0;
 
   Double_t am = p[1] - p[3];
   Double_t s = (*x - am) / p[4];
   Double_t gum = (fkFac / p[4]);
   Double_t es = -fRank * (s + TMath::Exp(-s));
   gum *= TMath::Exp(es);
 
   Double_t gau = fkGaussNor / p[2];
   s = (*x - p[1]) / p[2];
   s = TMath::Power(s, 2.) / 2.;
   gau *= TMath::Exp(-s);
 
   Double_t gg = p[0] * gau + (1. - p[0]) * gum;
   return gg;
}