coverity fix
[u/mrichter/AliRoot.git] / TPC / AliTPCPRF2D.cxx
index 58e739d..4f8d636 100644 (file)
  * provided "as is" without express or implied warranty.                  *
  **************************************************************************/
 
-/*
-$Log$
-*/
+/* $Id$ */
 
 ///////////////////////////////////////////////////////////////////////////////
-//  AliTPCPRF2D -                                                                         //
+//  AliTPCPRF2D -                                                            //
 //  Pad response function object in two dimesions                            //
 //  This class contains the basic functions for the                          //
 //  calculation of PRF according generic charge distribution                 //
@@ -30,92 +28,129 @@ $Log$
 //  Origin: Marian Ivanov, Uni. of Bratislava, ivanov@fmph.uniba.sk          //
 //                                                                           //
 ///////////////////////////////////////////////////////////////////////////////
-#include "TMath.h"
-#include "AliTPCPRF2D.h"
-#include "TF2.h"
-#include <iostream.h>
+
+#include <Riostream.h>
+#include <TCanvas.h>
+#include <TClass.h>
+#include <TF2.h>
+#include <TH1.h> 
+#include <TMath.h>
+#include <TPad.h>
+#include <TPaveText.h>
+#include <TStyle.h>
+#include <TText.h>
 #include <string.h>
-#include "TCanvas.h"
-#include "TPad.h"
-#include "TStyle.h"
-#include "TH1.h"
-#include "TH2.h"
-#include "TPaveText.h"
-#include "TText.h"
+
+#include "AliH2F.h"
+#include "AliTPCPRF2D.h"
+
 
 extern TStyle * gStyle;
 
-static const Float_t sqrt12=3.46;
-static const Int_t   NPRF = 100;
+const Double_t AliTPCPRF2D::fgkDegtoRad = 0.01745329251994;
+const Double_t AliTPCPRF2D::fgkSQRT12=3.464101;
+const Int_t   AliTPCPRF2D::fgkNPRF = 100;
 
 
-static Double_t funGauss2D(Double_t *x, Double_t * par)
+static Double_t FunGauss2D(const Double_t *const x, const Double_t *const par)
 { 
+//Gauss function  -needde by the generic function object 
   return ( TMath::Exp(-(x[0]*x[0])/(2*par[0]*par[0]))*
           TMath::Exp(-(x[1]*x[1])/(2*par[1]*par[1])));
 
 }
 
-static Double_t funCosh2D(Double_t *x, Double_t * par)
+static Double_t FunCosh2D(const Double_t *const x, const Double_t *const par)
 {
+ //Cosh function  -needde by the generic function object 
   return ( 1/(TMath::CosH(3.14159*x[0]/(2*par[0]))*
           TMath::CosH(3.14159*x[1]/(2*par[1]))));
 }    
 
-static Double_t funGati2D(Double_t *x, Double_t * par)
+static Double_t FunGati2D(const Double_t *const x, const Double_t *const par)
 {
-  //par[1] = is equal to k3X
-  //par[0] is equal to pad wire distance
-  Float_t K3=par[1];
-  Float_t K3R=TMath::Sqrt(K3);
-  Float_t K2=(TMath::Pi()/2)*(1-K3R/2.);
-  Float_t K1=K2*K3R/(4*TMath::ATan(K3R));
+  //Gati function  -needde by the generic function object 
+  Float_t k3=par[1];
+  Float_t k3R=TMath::Sqrt(k3);
+  Float_t k2=(TMath::Pi()/2)*(1-k3R/2.);
+  Float_t k1=k2*k3R/(4*TMath::ATan(k3R));
   Float_t l=x[0]/par[0];
-  Float_t tan2=TMath::TanH(K2*l);
+  Float_t tan2=TMath::TanH(k2*l);
   tan2*=tan2;
-  Float_t res = K1*(1-tan2)/(1+K3*tan2);
+  Float_t res = k1*(1-tan2)/(1+k3*tan2);
  //par[4] = is equal to k3Y
-  K3=par[4];
-  K3R=TMath::Sqrt(K3);
-  K2=(TMath::Pi()/2)*(1-K3R/2.);
-  K1=K2*K3R/(4*TMath::ATan(K3R));
+  k3=par[4];
+  k3R=TMath::Sqrt(k3);
+  k2=(TMath::Pi()/2)*(1-k3R/2.);
+  k1=k2*k3R/(4*TMath::ATan(k3R));
   l=x[1]/par[0];
-  tan2=TMath::TanH(K2*l);
+  tan2=TMath::TanH(k2*l); 
   tan2*=tan2;
-  res = res*K1*(1-tan2)/(1+K3*tan2);  
+  res = res*k1*(1-tan2)/(1+k3*tan2);   
   return res;  
 }   
 
-
-///////////////////////////////////////////////////////////////////////////
-///////////////////////////////////////////////////////////////////////////
 ///////////////////////////////////////////////////////////////////////////
 ///////////////////////////////////////////////////////////////////////////
 
 ClassImp(AliTPCPRF2D)
 
 AliTPCPRF2D::AliTPCPRF2D()
+            :TObject(),
+             fcharge(0),
+             fY1(0.),
+             fY2(0.),
+             fNYdiv(0),
+             fNChargeArray(0),
+             fChargeArray(0),
+             fHeightFull(0.),
+             fHeightS(0.),
+             fShiftY(0.),
+             fWidth(0.),
+             fK(0.),
+             fNPRF(0),
+             fNdiv(5),
+             fDStep(0.),
+             fKNorm(1.),
+             fInteg(0.),
+             fGRF(0),
+             fK3X(0.),
+             fK3Y(0.),
+             fPadDistance(0.),
+             fOrigSigmaX(0.),
+             fOrigSigmaY(0.),
+             fChargeAngle(0.),
+             fPadAngle(0.),
+             fSigmaX(0.),
+             fSigmaY(0.),
+             fMeanX(0.),
+             fMeanY(0.),
+             fInterX(0),
+             fInterY(0),
+             fCurrentY(0.),
+             fDYtoWire(0.),
+             fDStepM1(0.)             
 {
-  ffcharge = 0;
-  fNPRF =NPRF ;
-  fSigmaX = 0;
+  //default constructor for response function object
+
+  fNPRF =fgkNPRF ;
+  for(Int_t i=0;i<5;i++){
+        funParam[i]=0.;
+        fType[i]=0;
+  }
+  
 
-  fGRF = 0;
-  fkNorm = 1;
-  forigsigmaY=0;
-  forigsigmaX=0;
-  fNdiv = 5;
   //chewron default values   
   SetPad(0.8,0.8);
   SetChevron(0.2,0.0,1.0);
   SetY(-0.2,0.2,2);
-  // SetGauss(0.22,0.22,1);  
+  SetInterpolationType(2,0);
 }
 
 AliTPCPRF2D::~AliTPCPRF2D()
 {
-  if (ffcharge!=0) delete [] ffcharge;
-  if (fGRF !=0 ) fGRF->Delete();
+  if (fChargeArray!=0) delete [] fChargeArray;
+  if (fGRF !=0 ) fGRF->Delete(); 
 }
 
 void AliTPCPRF2D::SetY(Float_t y1, Float_t y2, Int_t nYdiv)
@@ -124,8 +159,6 @@ void AliTPCPRF2D::SetY(Float_t y1, Float_t y2, Int_t nYdiv)
   //set virtual line position
   //first and last line and number of lines
   fNYdiv = nYdiv;
-  if (ffcharge!=0) delete [] ffcharge;
-  ffcharge = new Float_t[fNPRF*fNYdiv];
   fY1=y1;
   fY2=y2;
 }
@@ -143,7 +176,7 @@ void AliTPCPRF2D::SetChevron(Float_t hstep,
   //set shaping of chewron parameters
   fHeightS=hstep;
   fShiftY=shifty;
-  fK=fWidth*fac/hstep;
+  fK=fac;
 }
 
 void AliTPCPRF2D::SetChParam(Float_t width, Float_t height,
@@ -154,74 +187,74 @@ void AliTPCPRF2D::SetChParam(Float_t width, Float_t height,
 }
 
 
-Float_t AliTPCPRF2D::GetPRF(Float_t xin, Float_t yin, Bool_t inter)
+Float_t AliTPCPRF2D::GetPRF(Float_t xin, Float_t yin)
 {
-  if (ffcharge==0) return 0;
-  //  Float_t y=Float_t(fNYdiv-1)*(yin-fY1)/(fY2-fY1);
+  //function which return pad response
+  //for the charge in distance xin 
+  //return  cubic aproximation of PRF or PRF at nearest virtual wire
+   if (fChargeArray==0) return 0;
   //transform position to "wire position"
   Float_t y=fDYtoWire*(yin-fY1);
   if (fNYdiv == 1) y=fY1;
   //normaly it find nearest line charge
-  if (inter ==kFALSE){   
+  if (fInterY ==0){   
     Int_t i=Int_t(0.5+y);
     if (y<0) i=Int_t(-0.5+y);
     if ((i<0) || (i>=fNYdiv) ) return 0;
-    fcharge   = &(ffcharge[i*fNPRF]);
+    fcharge   = &(fChargeArray[i*fNPRF]);
     return GetPRFActiv(xin);
   }
-  else{
-    //make interpolation from more fore lines
-    Int_t i= Int_t(y);
-    if ((i<0) || (i>=fNYdiv) ) return 0;
-    Float_t z0=0;
-    Float_t z1=0;
-    Float_t z2=0;
-    Float_t z3=0;
-    if (i>0) {
-      fcharge =&(ffcharge[(i-1)*fNPRF]);
-      z0 = GetPRFActiv(xin);
-    }
-    fcharge =&(ffcharge[i*fNPRF]);
-    z1=GetPRFActiv(xin);
-    if ((i+1)<fNYdiv){
-      fcharge =&(ffcharge[(i+1)*fNPRF]);
-      z2 = GetPRFActiv(xin);
-    }
-    if ((i+2)<fNYdiv){
-      fcharge =&(ffcharge[(i+2)*fNPRF]);
-      z3 = GetPRFActiv(xin);
-    }
-    Float_t a,b,c,d,K,L;
-    a=z1;
-    b=(z2-z0)/2.;
-    K=z2-a-b;
-    L=(z3-z1)/2.-b;
-    d=L-2*K;
-    c=K-d;
-    Float_t dy=y-Float_t(i);
-        Float_t res = a+b*dy+c*dy*dy+d*dy*dy*dy;  
-       //Float_t res = z1*(1-dy)+z2*dy;
-    return res;            
-  }        
-  return 0.;
+  //make interpolation from more fore lines
+  Int_t i= Int_t(y);
+  Float_t res;
+  if ((i<0) || (i>=fNYdiv) ) return 0;
+  Float_t z0=0;
+  Float_t z1=0;
+  Float_t z2=0;
+  Float_t z3=0;
+  if (i>0) {
+    fcharge =&(fChargeArray[(i-1)*fNPRF]);
+    z0 = GetPRFActiv(xin);
+  }
+  fcharge =&(fChargeArray[i*fNPRF]);
+  z1=GetPRFActiv(xin);
+  if ((i+1)<fNYdiv){
+    fcharge =&(fChargeArray[(i+1)*fNPRF]);
+    z2 = GetPRFActiv(xin);
+  }
+  if ((i+2)<fNYdiv){
+    fcharge =&(fChargeArray[(i+2)*fNPRF]);
+    z3 = GetPRFActiv(xin);
+  }
+  Float_t a,b,c,d,k,l;
+  a=z1;
+  b=(z2-z0)/2.;
+  k=z2-a-b;
+  l=(z3-z1)/2.-b;
+  d=l-2*k;
+  c=k-d;
+  Float_t dy=y-Float_t(i);
+  
+  res = a+b*dy+c*dy*dy+d*dy*dy*dy;  
+  return res;            
 } 
 
 
 Float_t AliTPCPRF2D::GetPRFActiv(Float_t xin)
 {
-  //x xin DStep unit
-  //return splaine aproximaton 
+  //GEt response function on given charege line 
+  //return spline aproximaton 
   Float_t x = (xin*fDStepM1)+fNPRF/2;
   Int_t i = Int_t(x);
   
-  if  ( (i>0) && ((i+2)<fNPRF)) {
-    Float_t a,b,c,d,K,L;
+  if  ( (i>1) && ((i+2)<fNPRF)) {
+    Float_t a,b,c,d,k,l;
     a = fcharge[i];
     b = (fcharge[i+1]-fcharge[i-1])*0.5; 
-    K = fcharge[i+1]-a-b;
-    L = (fcharge[i+2]-fcharge[i])*0.5-b;
-    d=L-2.*K;
-    c=K-d;
+    k = fcharge[i+1]-a-b;
+    l = (fcharge[i+2]-fcharge[i])*0.5-b;
+    d=l-2.*k;
+    c=k-d;
     Float_t dx=x-Float_t(i);
     Float_t res = a+b*dx+c*dx*dx+d*dx*dx*dx;  
     return res;
@@ -232,522 +265,712 @@ Float_t AliTPCPRF2D::GetPRFActiv(Float_t xin)
 
 Float_t  AliTPCPRF2D::GetGRF(Float_t xin, Float_t yin)
 {  
-  if (fGRF != 0 ) 
-    return fkNorm*fGRF->Eval(xin,yin)/fInteg;
+  //function which returnoriginal charge distribution
+  //this function is just normalised for fKnorm
+  if (GetGRF() != 0 ) 
+    return fKNorm*GetGRF()->Eval(xin,yin)/fInteg;
       else
     return 0.;
 }
 
    
-void AliTPCPRF2D::SetParam( TF2 * GRF,  Float_t kNorm, 
+void AliTPCPRF2D::SetParam( TF2 *const GRF,  Float_t kNorm, 
                       Float_t sigmaX, Float_t sigmaY)
 {
+  //adjust parameters of the original charge distribution
+  //and pad size parameters
    if (fGRF !=0 ) fGRF->Delete();
    fGRF = GRF;
-   fkNorm = kNorm;
-   if (sigmaX ==0) sigmaX=(fWidth+fK*fHeightS)/sqrt12;
-   if (sigmaY ==0) sigmaY=(fWidth+fK*fHeightS)/sqrt12;
-   forigsigmaX=sigmaX; 
-   forigsigmaY=sigmaY; 
-   fDStep = TMath::Sqrt(sigmaX*sigmaX+fWidth*fWidth/6.)/10.; 
-   //   Update();   
-  sprintf(fType,"User");
+   fKNorm = kNorm;
+   //sprintf(fType,"User");
+   snprintf(fType,5,"User");
+   if (sigmaX ==0) sigmaX=(fWidth*(1+TMath::Abs(fK)))/fgkSQRT12;
+   if (sigmaY ==0) sigmaY=(fWidth*(1+TMath::Abs(fK)))/fgkSQRT12;
+   fOrigSigmaX=sigmaX; 
+   fOrigSigmaY=sigmaY; 
+   Double_t estimsigma = 
+     TMath::Sqrt(sigmaX*sigmaX+(fWidth*fWidth*(1+TMath::Abs(fK))/12)+
+                TMath::Tan(fPadAngle*fgkDegtoRad)*TMath::Tan(fPadAngle*fgkDegtoRad)*fHeightFull*fHeightFull/12);   
+   if (estimsigma < 5*sigmaX) {
+     fDStep = estimsigma/10.;
+     fNPRF  = Int_t(estimsigma*8./fDStep); 
+   }
+   else{
+     fDStep = sigmaX; 
+     Double_t width = fWidth*(1+TMath::Abs(fK))+TMath::Abs(TMath::Tan(fPadAngle*fgkDegtoRad))*fHeightFull;
+     fNPRF = Int_t((width+8.*sigmaX)/fDStep);
+   };
+
 }
   
 
 void AliTPCPRF2D::SetGauss(Float_t sigmaX, Float_t sigmaY,
                      Float_t kNorm)
 {
-  fkNorm = kNorm;
+  // 
+  // set parameters for Gauss generic charge distribution
+  //
+  fKNorm = kNorm;
+  fOrigSigmaX=sigmaX;
+  fOrigSigmaY=sigmaY;
+  //sprintf(fType,"Gauss");
+  snprintf(fType,5,"Gauss");
   if (fGRF !=0 ) fGRF->Delete();
-  fGRF = new TF2("fun",funGauss2D,-5.,5.,-5.,5.,4);
+  fGRF = new TF2("FunGauss2D",FunGauss2D,-5.,5.,-5.,5.,4);
+  
   funParam[0]=sigmaX;
   funParam[1]=sigmaY;  
   funParam[2]=fK;
   funParam[3]=fHeightS;    
-  forigsigmaX=sigmaX;
-  forigsigmaY=sigmaY;
-  fGRF->SetParameters(funParam);
-  fDStep = TMath::Sqrt(sigmaX*sigmaX+fWidth*fWidth/6.)/10.; 
-  //by default I set the step as one tenth of sigma
-  //Update();
-  sprintf(fType,"Gauss");
+  fGRF->SetParameters(funParam); 
+  Double_t estimsigma = 
+     TMath::Sqrt(sigmaX*sigmaX+(fWidth*fWidth*(1+TMath::Abs(fK))/12)+
+                TMath::Tan(fPadAngle)*TMath::Tan(fPadAngle*fgkDegtoRad)*fHeightFull*fHeightFull/12);   
+   if (estimsigma < 5*sigmaX) {
+     fDStep = estimsigma/10.;
+     fNPRF  = Int_t(estimsigma*8./fDStep); 
+   }
+   else{
+     fDStep = sigmaX; 
+     Double_t width = fWidth*(1+TMath::Abs(fK))+TMath::Abs(TMath::Tan(fPadAngle*fgkDegtoRad))*fHeightFull;
+     fNPRF = Int_t((width+8.*sigmaX)/fDStep);
+   };
+  
 }
-
 void AliTPCPRF2D::SetCosh(Float_t sigmaX, Float_t sigmaY,
                     Float_t kNorm)
-{
-  fkNorm = kNorm;
+{ 
+  // set parameters for Cosh generic charge distribution
+  //
+  fKNorm = kNorm;
+  fOrigSigmaX=sigmaX;
+  fOrigSigmaY=sigmaY; 
+  //  sprintf(fType,"Cosh");
+  snprintf(fType,5,"Cosh");
   if (fGRF !=0 ) fGRF->Delete();
-  fGRF = new TF2("fun",        funCosh2D,-5.,5.,-5.,5.,4);   
+  fGRF = new TF2("FunCosh2D",  FunCosh2D,-5.,5.,-5.,5.,4);   
   funParam[0]=sigmaX;
   funParam[1]=sigmaY;
   funParam[2]=fK;  
   funParam[3]=fHeightS;
   fGRF->SetParameters(funParam);
-  forigsigmaX=sigmaX;
-  forigsigmaY=sigmaY;
-  fDStep = TMath::Sqrt(sigmaX*sigmaX+fWidth*fWidth/6.)/10.; 
-  //by default I set the step as one tenth of sigma
-  //Update();
-  sprintf(fType,"Cosh");
+
+  Double_t estimsigma = TMath::Sqrt(sigmaX*sigmaX+fWidth*fWidth*(1+TMath::Abs(fK))/12);   
+  if (estimsigma < 5*sigmaX) {
+    fDStep = estimsigma/10.;
+    fNPRF  = Int_t(estimsigma*8./fDStep); 
+  }
+  else{
+    fDStep = sigmaX; 
+    fNPRF = Int_t((1.2*fWidth*(1+TMath::Abs(fK))+8.*sigmaX)/fDStep);
+  };  
 }
 
 void AliTPCPRF2D::SetGati(Float_t K3X, Float_t K3Y,
                     Float_t padDistance,
                     Float_t kNorm)
 {
-  fkNorm = kNorm;
-  if (fGRF !=0 ) fGRF->Delete();
-  fGRF = new TF2("fun",        funGati2D,-5.,5.,-5.,5.,5);  
+  // set parameters for Gati generic charge distribution
+  //
+  fKNorm = kNorm;
   fK3X=K3X;
   fK3Y=K3Y;
-  fPadDistance=padDistance;
+  fPadDistance=padDistance;  
+  //sprintf(fType,"Gati");
+  snprintf(fType,5,"Gati");
+  if (fGRF !=0 ) fGRF->Delete();
+  fGRF = new TF2("FunGati2D",  FunGati2D,-5.,5.,-5.,5.,5);  
   funParam[0]=padDistance;
   funParam[1]=K3X;
   funParam[2]=fK;  
   funParam[3]=fHeightS;
   funParam[4]=K3Y;
   fGRF->SetParameters(funParam);
-  forigsigmaX=padDistance;
-  forigsigmaY=padDistance;
-  fDStep = TMath::Sqrt(padDistance*padDistance+fWidth*fWidth/6.)/10.; 
-  //by default I set the step as one tenth of sigma
-  //Update();
-  sprintf(fType,"Gati");
+  fOrigSigmaX=padDistance;
+  fOrigSigmaY=padDistance;
+  Float_t sigmaX = fOrigSigmaX;
+  Double_t estimsigma = TMath::Sqrt(sigmaX*sigmaX+fWidth*fWidth*(1+TMath::Abs(fK))/12);   
+  if (estimsigma < 5*sigmaX) {
+    fDStep = estimsigma/10.;
+    fNPRF  = Int_t(estimsigma*8./fDStep); 
+  }
+  else{
+    fDStep = sigmaX; 
+    fNPRF = Int_t((1.2*fWidth*(1+TMath::Abs(fK))+8.*sigmaX)/fDStep);
+  };
 }
 
 
 
 void AliTPCPRF2D::Update()
 {
-  for (Int_t i=0; i<fNYdiv; i++){
-    if (fNYdiv == 1) fActualY = fY1;
+  //
+  //update fields  with interpolated values for
+  //PRF calculation
+
+  if ( fGRF == 0 ) return;  
+  //initialize interpolated values to 0
+  Int_t i;
+  if (fChargeArray!=0) delete [] fChargeArray;
+  fChargeArray = new Float_t[fNPRF*fNYdiv];
+  fNChargeArray = fNPRF*fNYdiv;
+  for (i =0; i<fNPRF*fNYdiv;i++)  fChargeArray[i] = 0;
+  //firstly calculate total integral of charge
+
+  ////////////////////////////////////////////////////////
+  //I'm waiting for normal integral
+  //in this moment only sum
+  Float_t x2=  4*fOrigSigmaX;
+  Float_t y2=  4*fOrigSigmaY;
+  Float_t dx = fOrigSigmaX/Float_t(fNdiv*6);
+  Float_t dy = fOrigSigmaY/Float_t(fNdiv*6);  
+  Int_t nx  = Int_t(0.5+x2/dx);
+  Int_t ny  = Int_t(0.5+y2/dy);
+  Int_t ix,iy;
+  fInteg  = 0;
+  Double_t dInteg =0;
+  for (ix=-nx;ix<=nx;ix++)
+    for ( iy=-ny;iy<=ny;iy++) 
+      dInteg+=fGRF->Eval(Float_t(ix)*dx,Float_t(iy)*dy)*dx*dy;  
+  /////////////////////////////////////////////////////
+  fInteg =dInteg;
+  if ( fInteg == 0 ) fInteg = 1; 
+
+  for (i=0; i<fNYdiv; i++){
+    if (fNYdiv == 1) fCurrentY = fY1;
     else
-      fActualY = fY1+Float_t(i)*(fY2-fY1)/Float_t(fNYdiv-1);
-    fcharge   = &(ffcharge[i*fNPRF]);
+      fCurrentY = fY1+Double_t(i)*(fY2-fY1)/Double_t(fNYdiv-1);
+    fcharge   = &(fChargeArray[i*fNPRF]);
     Update1();
   }
+  //calculate conversion coefitient to convert position to virtual wire
+  fDYtoWire=Float_t(fNYdiv-1)/(fY2-fY1);
+  fDStepM1=1/fDStep;
+  UpdateSigma();
 }
 
-
-
 void AliTPCPRF2D::Update1()
 {
-  //initialize to 0
-  
-
+  //
+  //update fields  with interpolated values for
+  //PRF calculation for given charge line
   Int_t i;
-  Float_t x;
-  for (i =0; i<fNPRF;i++)  fcharge[i] = 0;
-  if ( fGRF == 0 ) return;
-  ////////////////////////////////////////////////////////
-  //I'm waiting for normal integral
-  //in this moment only sum
-  Float_t x2=  4*forigsigmaX;
-  Float_t y2=  4*forigsigmaY;
-  Float_t dx = forigsigmaX/Float_t(fNdiv*6);
-  Float_t dy = forigsigmaY/Float_t(fNdiv*6);  
-  fInteg  = 0;
-  for (x=0.;x<x2;x+=dx)
-    for (Float_t y=0;y<y2;y+=dy) fInteg+=fGRF->Eval(x,y)*dx*dy;
-  fInteg*=4;
-  /////////////////////////////////////////////////////
+  Double_t cos = TMath::Cos(fChargeAngle);
+  Double_t sin = TMath::Sin(fChargeAngle);
+  const Double_t kprec =0.00000001;
+  //integrate charge over pad for different distance of pad
+  for (i =0; i<fNPRF;i++){      
+    //x in cm fWidth in cm
+    //calculate integral 
+    Double_t xch = fDStep * (Double_t)(i-fNPRF/2);
+    fcharge[i]=0;
+    Double_t k=1;  
+    
+    
+    for (Double_t ym=-fHeightFull/2.-fShiftY;  ym<fHeightFull/2.-kprec;ym+=fHeightS){  
+      Double_t y2chev=TMath::Min((ym+fHeightS),Double_t(fHeightFull/2.)); // end of chevron step
+      Double_t y1chev= ym;  //beginning of chevron step
+      Double_t y2 = TMath::Min(y2chev,fCurrentY+3.5*fOrigSigmaY);
+      Double_t y1 = TMath::Max((y1chev),Double_t(-fHeightFull/2.));
+      y1 = TMath::Max(y1chev,fCurrentY-3.5*fOrigSigmaY);
+
+      Double_t x0 = fWidth*(-1.-(Double_t(k)*fK))*0.5+ym*TMath::Tan(fPadAngle*fgkDegtoRad);
+      Double_t kx  = Double_t(k)*(fK*fWidth)/fHeightS;     
+      kx = TMath::Tan(TMath::ATan(kx))+TMath::Tan(fPadAngle*fgkDegtoRad);     
+
+      Int_t ny = TMath::Max(Int_t(fNdiv*TMath::Exp(-(y1-fCurrentY)*(y1-fCurrentY)/(2*fOrigSigmaY*fOrigSigmaY))),4);
+      Double_t dy = TMath::Min(fOrigSigmaY/Double_t(ny),y2-y1);
+      Double_t ndy = dy;
       
-  
-  if ( fInteg == 0 ) fInteg = 1; 
-  
-    //integrate charge over pad for different distance of pad
-    for (i =0; i<fNPRF;i++)
-      {      //x in cm fWidth in cm
-       //calculate integral 
-       Float_t xch = fDStep * (Float_t)(i-fNPRF/2);
-       Float_t k=1;
-       fcharge[i]=0;
-       for (Float_t y=-fHeightFull/2.-fShiftY;
-            y<fHeightFull/2.;y+=fHeightS){
-         Float_t y2=TMath::Min((y+fHeightS),Float_t(fHeightFull/2.));
-         Float_t y1=TMath::Max((y),Float_t(-fHeightFull/2.));
-         Float_t x1;
+      //loop over different y strips with variable step size  dy
+      if (y2>(y1+kprec)) for (Double_t y = y1; y<y2+kprec;){      
+       //new step SIZE 
        
-         if (k>0) 
-           x1 = (y2-y1)*fK-(fWidth+fK*fHeightS)/2.;      
-         else
-           x1 =-(fWidth+fK*fHeightS)/2. ;        
-         Float_t x2=x1+fWidth;
-
-         if (y2>y1) {
-           
-            if ((x2-x1)*fNdiv<forigsigmaX) dx=(x2-x1);
-           else{
-             dx= forigsigmaX/Float_t(fNdiv);
-             dx = (x2-x1)/Float_t(Int_t(3+(x2-x1)/dx));          
-           }       
-           Float_t dy;
-           if ((y2-y1)*fNdiv<forigsigmaY) dy=(y2-y1);
-           else{             
-             dy= forigsigmaY/Float_t(fNdiv);
-             dy = (y2-y1)/Float_t(Int_t(3+(y2-y1)/dy));
+       ny = TMath::Max(Int_t(fNdiv*TMath::Exp(-(y-fCurrentY)*(y-fCurrentY)/(2*fOrigSigmaY*fOrigSigmaY))),5);
+       ndy = fOrigSigmaY/Double_t(ny); 
+       if (ndy>(y2-y-dy)) {
+         ndy =y2-y-dy;
+         if (ndy<kprec) ndy=2*kprec; //calculate new delta y
+       }
+       //              
+       Double_t sumch=0;
+       //calculation of x borders and initial step
+       Double_t deltay = (y-y1chev);           
+
+       Double_t xp1  = x0+deltay*kx;
+                //x begining of pad at position y
+       Double_t xp2 =xp1+fWidth;        //x end of pad at position y
+       Double_t xp3 =xp1+kx*dy; //...at position y+dy
+       Double_t xp4 =xp2+kx*dy; //..  
+       
+       Double_t x1 = TMath::Min(xp1,xp3);
+       x1 = TMath::Max(xp1,xch-3.5*fOrigSigmaX); //beging of integration
+       Double_t x2 = TMath::Max(xp2,xp4);
+        x2 = TMath::Min(xp2+dy*kx,xch+3.5*fOrigSigmaX); //end of integration
+
+       Int_t nx = TMath::Max(Int_t(fNdiv*TMath::Exp(-(x1-xch)*(x1-xch)/(2*fOrigSigmaX*fOrigSigmaX))*
+                                   TMath::Exp(-(y1-fCurrentY)*(y1-fCurrentY)/(2*fOrigSigmaY*fOrigSigmaY))),2);
+       Double_t dx = TMath::Min(fOrigSigmaX/Double_t(nx),x2-x1)/5.; //on the border more iteration
+       Double_t ndx=dx;
+       
+       if (x2>(x1+kprec)) {
+         for (Double_t x = x1; x<x2+kprec ;){
+         //new step SIZE         
+         nx = TMath::Max(Int_t(fNdiv*TMath::Exp(-(x-xch)*(x-xch)/(2*fOrigSigmaX*fOrigSigmaX))),3);       
+         ndx = fOrigSigmaX/Double_t(nx);
+         if (ndx>(x2-x-dx)) {
+           ndx =x2-x-dx;                  
+         }
+          if ( ( (x+dx+ndx)<TMath::Max(xp3,xp1)) || ( (x+dx+ndx)>TMath::Min(xp4,xp2))) {
+           ndx/=5.;
+         }       
+         if (ndx<kprec) ndx=2*kprec;
+         //INTEGRAL APROXIMATION
+         Double_t ddx,ddy,dddx,dddy;
+         ddx = xch-(x+dx/2.);
+         ddy = fCurrentY-(y+dy/2.);
+         dddx = cos*ddx-sin*ddy;
+         dddy = sin*ddx+cos*ddy;
+         Double_t z0=fGRF->Eval(dddx,dddy);  //middle point
+         
+         ddx = xch-(x+dx/2.);
+         ddy = fCurrentY-(y);
+         dddx = cos*ddx-sin*ddy;
+         dddy = sin*ddx+cos*ddy;
+         Double_t z1=fGRF->Eval(dddx,dddy);  //point down
+         
+         ddx = xch-(x+dx/2.);
+         ddy = fCurrentY-(y+dy);
+         dddx = cos*ddx-sin*ddy;
+         dddy = sin*ddx+cos*ddy;
+         Double_t z3=fGRF->Eval(dddx,dddy);  //point up
+         
+         ddx = xch-(x);
+         ddy = fCurrentY-(y+dy/2.);
+         dddx = cos*ddx-sin*ddy;
+         dddy = sin*ddx+cos*ddy;
+         Double_t z2=fGRF->Eval(dddx,dddy);  //point left  
+         
+         ddx = xch-(x+dx);
+         ddy = fCurrentY-(y+dy/2.);
+         dddx = cos*ddx-sin*ddy;
+         dddy = sin*ddx+cos*ddy;
+         Double_t z4=fGRF->Eval(dddx,dddy);  //point right
+         
+         
+         if (z0<0) {z0=0;z1=0;z2=0;z3=0;z4=0;}
+         
+         Double_t f2x= (z3+z1-2*z0)*4.;//second derivation in y
+         Double_t f2y= (z2+z4-2*z0)*4.;//second derivation in x
+         Double_t f1y= (z3-z1);
+         Double_t z ;    
+         z = (z0+f2x/6.+f2y/6.);//second order aproxiation of integral     
+         if (kx>kprec){  //positive derivation
+           if (x<(xp1+dy*kx)){                //calculate volume at left border 
+             Double_t xx1  = x;
+             Double_t xx2  = TMath::Min(x+dx,xp1+dy*kx);
+             Double_t yy1  = y+(xx1-xp1)/kx;
+             Double_t yy2  = TMath::Min(y+(xx2-xp1)/kx,y+dy);        
+             z=z0;
+             if (yy2<y+dy) {           
+               z-= z0*(y+dy-yy2)/dy; //constant part rectangle
+               z-= f1y*(xx2-xx1)*(y+dy-yy2)*(y+dy-yy2)/(2.*dx*dy);
+             }
+             z-=z0*(xx2-xx1)*(yy2-yy1)/(2*dx*dy); //constant part rectangle
+             
+           }
+           if (x>xp2){          //calculate volume at right  border 
+             Double_t xx1  = x;
+             Double_t xx2  = x+dx;
+             Double_t yy1  = y+(xx1-xp2)/kx;
+             Double_t yy2  = y+(xx2-xp2)/kx;                
+             z=z0;
+             //rectangle part
+             z-=z0*(yy1-y)/dy; //constant part
+             z-=f1y*(xx2-xx1)*(yy1-y)*(yy1-y)/(2*dx*dy);
+             //triangle part         
+             z-=z0*(xx2-xx1)*(yy2-yy1)/(2*dx*dy); //constant part            
            }
+         }       
+         if (kx<-kprec){ //negative  derivation            
+           if (x<(xp1+dy*kx)){       //calculate volume at left border          
+             Double_t xx1  = x;
+             Double_t xx2  = TMath::Min(x+dx,xp3-dy/kx);
+             Double_t yy1  = y+(xx1-xp1)/kx;
+             Double_t yy2  = TMath::Max(y,yy1+(xx2-xx1)/kx); //yy2<yy1 
+             z = z0;
+             z-= z0*(yy2-y)/dy; // constant part rectangle 
+             z-= f1y*(xx2-xx1)*(yy2-y)*(yy2-y)/(2.*dx*dy); 
+             z-=z0*(xx2-xx1)*(yy1-yy2)/(2*dx*dy); //constant part triangle
+           }
+           if (x>xp2){       //calculate volume at right  border 
+             Double_t xx1  = TMath::Max(x,xp2+dy*kx);
+             Double_t xx2  = x+dx;
+             Double_t yy1  = TMath::Min(y+dy,y-(xp2-xx1)/kx);
+             Double_t yy2  = y-(xp2-xx2)/kx;
+             z=z0;
+             z-=z0*(yy2-y)/dy;  //constant part rextangle
+             z-= f1y*(xx2-xx1)*(yy2-y)*(yy2-y)/(2.*dx*dy); 
+             z-=z0*(xx2-xx1)*(yy1-yy2)/(2*dx*dy); //constant part triangle
+           }               
+         }     
+              
+         if (z>0.)           sumch+=fKNorm*z*dx*dy/fInteg;
+         
+         x+=dx;
+         dx = ndx;
+       }; //loop over x          
+       fcharge[i]+=sumch;
+       }//if x2>x1
+       y+=dy;
+       dy =ndy;
+      }//step over different y
+      k*=-1.;
+    }//step over chevron 
+    
+   }//step over different points on line NPRF
+}
 
-           for (x=x1;x<x2;x+=dx)
-             for (Float_t y=y1;y<y2;y+=dy){
-               if ( (y>(fActualY-(4.0*forigsigmaY))) &&
-                    (y<(fActualY+(4.0*forigsigmaY)))){
-                 Float_t xt=x-k*fK*(y-y1); 
-                 if ((TMath::Abs(xch-xt)<4*forigsigmaX)){
-                   
-                   Float_t z0=fGRF->Eval(xch-(xt+dx/2.),fActualY-(y+dy/2.));
-                   
-                   Float_t z1=fGRF->Eval(xch-(xt+dx/2.),fActualY-y);
-                   Float_t z2=fGRF->Eval(xch-xt,fActualY-(y+dy/2.));
-                   Float_t z3=fGRF->Eval(xch-(xt-dx/2.),fActualY-y);
-                   Float_t z4=fGRF->Eval(xch-xt,fActualY-(y-dy/2.));
-                   if (z0<0) z0=0;
-                   if (z1<0) z1=0;
-                   if (z2<0) z2=0;
-                   if (z3<0) z3=0;
-                   if (z4<0) z4=0;
-                   
-                   //        Float_t a=(z1-z3)/2;
-                   //        Float_t b=(z2-z4)/2;
-                   Float_t c= (z3+z1-2*z0)/2.;
-                   Float_t d= (z2+z4-2*z0)/2.;
-                   Float_t z= (z0+c/12.+d/12.);                                
-                   
-                   //Float_t z= fGRF->Eval(xch-xt,fActualY-y);
-                   if (z>0.)         fcharge[i]+=z*dx*dy/fInteg;             
-                 }
-               }
-             }
-         }
-         k*=-1;
-       }
-      };   
-  
-  fSigmaX = 0; 
+void AliTPCPRF2D::UpdateSigma()
+{
+  //
+  //calulate effective sigma X and sigma y of PRF
+  fMeanX = 0;
+  fMeanY = 0;
+  fSigmaX = 0;
+  fSigmaY = 0;
   Float_t sum =0;
-  Float_t mean=0;
-  for (x =-fNPRF*fDStep; x<fNPRF*fDStep;x+=fDStep)
-    {      //x in cm fWidth in cm
-      Float_t weight = GetPRFActiv(x);
-      fSigmaX+=x*x*weight; 
-      mean+=x*weight;
-      sum+=weight;
+  Int_t i;
+  Float_t x,y;
+
+  for (i=-1; i<=fNYdiv; i++){
+    if (fNYdiv == 1) y = fY1;
+    else
+      y = fY1+Float_t(i)*(fY2-fY1)/Float_t(fNYdiv-1);
+    for (x =-fNPRF*fDStep; x<fNPRF*fDStep;x+=fDStep)
+      {      
+       //x in cm fWidth in cm
+       Float_t weight = GetPRF(x,y);
+       fSigmaX+=x*x*weight; 
+       fSigmaY+=y*y*weight;
+       fMeanX+=x*weight;
+       fMeanY+=y*weight;
+       sum+=weight;
     };  
+  }
   if (sum>0){
-    mean/=sum;
-    fSigmaX = TMath::Sqrt(fSigmaX/sum-mean*mean);   
+    fMeanX/=sum;
+    fMeanY/=sum;    
+    fSigmaX = TMath::Sqrt(fSigmaX/sum-fMeanX*fMeanX);
+    fSigmaY = TMath::Sqrt(fSigmaY/sum-fMeanY*fMeanY);   
   }
   else fSigmaX=0; 
-  //calculate conversion coefitient to convert position to virtual wire
-  fDYtoWire=Float_t(fNYdiv-1)/(fY2-fY1);
-  fDStepM1=1/fDStep;
 }
 
-void AliTPCPRF2D::Streamer(TBuffer &R__b)
+
+void AliTPCPRF2D::Streamer(TBuffer &xRuub)
 {
    // Stream an object of class AliTPCPRF2D
 
-   if (R__b.IsReading()) {
-      Version_t R__v = R__b.ReadVersion(); if (R__v) { }
-      TObject::Streamer(R__b);     
-      //read chewron parameters
-      R__b >> fSigmaX;
-      R__b >> fHeightFull;
-      R__b >> fHeightS;
-      R__b >> fShiftY;
-      R__b >> fWidth;
-      R__b >> fK;
-      R__b >> fActualY;
-      //read charge parameters
-      R__b >> fType[0];
-      R__b >> fType[1];
-      R__b >> fType[2];
-      R__b >> fType[3];
-      R__b >> fType[4];
-      R__b >> forigsigmaX;
-      R__b >> forigsigmaY;
-      R__b >> fkNorm;
-      R__b >> fK3X;
-      R__b >> fK3Y;
-      R__b >> fPadDistance;
-      R__b >> fInteg;
-      
+   if (xRuub.IsReading()) {
+      UInt_t xRuus, xRuuc;
+      Version_t xRuuv = xRuub.ReadVersion(&xRuus, &xRuuc);
+      AliTPCPRF2D::Class()->ReadBuffer(xRuub, this, xRuuv, xRuus, xRuuc);
       //read functions
-      if (fGRF!=0) { 
-       delete [] fGRF;  
-       fGRF=0;
+      if (strncmp(fType,"User",3)!=0){
+       delete fGRF;  
+        if (strncmp(fType,"Gauss",3)==0) 
+         fGRF = new TF2("FunGauss2D",FunGauss2D,-5.,5.,-5.,5.,4);
+        if (strncmp(fType,"Cosh",3)==0) 
+         fGRF = new TF2("FunCosh2D",FunCosh2D,-5.,5.,-5.,5.,4);
+        if (strncmp(fType,"Gati",3)==0) 
+         fGRF = new TF2("FunGati2D",FunGati2D,-5.,5.,-5.,5.,5);      
+        if (fGRF!=0) fGRF->SetParameters(funParam);
       }
-      if (strncmp(fType,"User",3)==0){
-       fGRF= new TF2;
-       R__b>>fGRF;   
-      }
-      if (strncmp(fType,"Gauss",3)==0) 
-       fGRF = new TF2("fun",funGauss2D,-5.,5.,-5.,5.,4);
-      if (strncmp(fType,"Cosh",3)==0) 
-       fGRF = new TF2("fun",funCosh2D,-5.,5.,-5.,5.,4);
-       if (strncmp(fType,"Gati",3)==0) 
-       fGRF = new TF2("fun",funGati2D,-5.,5.,-5.,5.,5);
-      
-      //read interpolation parameters
-      R__b >>fY1;
-      R__b >>fY2;
-      R__b >>fNYdiv;  
-      R__b >>fDStep;  
-      R__b >>fNPRF;
-      if (ffcharge!=0) delete [] ffcharge;
-      ffcharge = new Float_t[fNPRF*fNYdiv];
-      R__b.ReadFastArray(ffcharge,fNPRF*fNYdiv); 
-      R__b.ReadFastArray(funParam,5); 
-      if (fGRF!=0) fGRF->SetParameters(funParam);
       //calculate conversion coefitient to convert position to virtual wire
       fDYtoWire=Float_t(fNYdiv-1)/(fY2-fY1);
       fDStepM1=1/fDStep;
    } else {
-      R__b.WriteVersion(AliTPCPRF2D::IsA());
-      TObject::Streamer(R__b);      
-      //write chewron parameters
-      R__b << fSigmaX;
-      R__b << fHeightFull;
-      R__b << fHeightS;
-      R__b << fShiftY;
-      R__b << fWidth;
-      R__b << fK;
-      R__b << fActualY;
-      //write charge parameters
-      R__b << fType[0];
-      R__b << fType[1];
-      R__b << fType[2];
-      R__b << fType[3];
-      R__b << fType[4];
-
-      R__b << forigsigmaX;
-      R__b << forigsigmaY;
-      R__b << fkNorm;
-      R__b << fK3X;
-      R__b << fK3Y;
-      R__b << fPadDistance;  
-      R__b << fInteg;
-
-      if (strncmp(fType,"User",3)==0)  R__b <<fGRF;         
-      //write interpolation parameters
-      R__b <<fY1;
-      R__b <<fY2;
-      R__b <<fNYdiv;   
-      R__b <<fDStep;
-      R__b <<fNPRF;    
-      R__b.WriteFastArray(ffcharge,fNPRF*fNYdiv); 
-      R__b.WriteFastArray(funParam,5); 
+      AliTPCPRF2D::Class()->WriteBuffer(xRuub,this);
    }
 }
 
 
-
-
-void AliTPCPRF2D::DrawX(Float_t x1 ,Float_t x2,Float_t y, Bool_t inter)
-{ 
-  if (fGRF==0) return ;
-  const Int_t N=100;
-  char s[100];
-  TCanvas  * c1 = new TCanvas("canPRF","Pad response function",700,900);
-  c1->cd();
-  TPad * pad1 = new TPad("pad1PRF","",0.05,0.61,0.95,0.97,21);
-  pad1->Draw();
-  TPad * pad2 = new TPad("pad2PRF","",0.05,0.22,0.95,0.60,21);
-  pad2->Draw();
-
-  //  pad1->cd();  
-  //pad2->cd();
-  gStyle->SetOptFit(1);
-  gStyle->SetOptStat(0); 
-  sprintf(s,"PRF response function for chevron pad");  
-  TH1F * hPRFc = new TH1F("hPRFc",s,N+1,x1,x2);
+TH1F *  AliTPCPRF2D::GenerDrawXHisto(Float_t x1, Float_t x2,Float_t y)
+{
+  //gener one dimensional hist of pad response function
+  //  at position y 
+  char s[100]; 
+  const Int_t kn=200;
+  //sprintf(s,"Pad Response Function"); 
+  snprintf(s,100,"Pad Response Function");  
+  TH1F * hPRFc = new TH1F("hPRFc",s,kn+1,x1,x2);
   Float_t x=x1;
   Float_t y1;
-  //  Float_t y2;
 
-  for (Float_t i = 0;i<N+1;i++)
+  for (Int_t i = 0;i<kn+1;i++)
     {
-      x+=(x2-x1)/Float_t(N);
-      y1 = GetPRF(x,y,inter);
+      x+=(x2-x1)/Float_t(kn);
+      y1 = GetPRF(x,y);
       hPRFc->Fill(x,y1);
     };
+  hPRFc->SetXTitle("pad  (cm)");
+  return hPRFc;
+}  
 
-  pad1->cd();
-  fGRF->SetRange(x1,x1,x2,x2); 
-  fGRF->SetNpx(25);
-  fGRF->SetNpy(25); 
-  fGRF->Draw("lego2");
-  // hPRFo->Fit("gaus");
-  gStyle->SetOptStat(1); 
-  pad2->cd();
-  hPRFc->Fit("gaus");
-  c1->cd(); 
+AliH2F * AliTPCPRF2D::GenerDrawHisto(Float_t x1, Float_t x2, Float_t y1, Float_t y2, Int_t Nx, Int_t Ny)
+{
+  //
+  //gener two dimensional histogram with PRF
+  //
+  char s[100];
+  //sprintf(s,"Pad Response Function"); 
+  snprintf(s,100,"Pad Response Function");  
+  AliH2F * hPRFc = new AliH2F("hPRFc",s,Nx,x1,x2,Ny,y1,y2);
+  Float_t dx=(x2-x1)/Float_t(Nx);
+  Float_t dy=(y2-y1)/Float_t(Ny) ;
+  Float_t x,y,z; 
+  x = x1;
+  y = y1;
+  for ( Int_t i  = 0;i<=Nx;i++,x+=dx){
+    y=y1;
+    for (Int_t j  = 0;j<=Ny;j++,y+=dy){
+      z = GetPRF(x,y);
+      hPRFc->SetCellContent(i,j,z);
+    };
+  }; 
+  hPRFc->SetXTitle("pad direction (cm)");
+  hPRFc->SetYTitle("pad row  direction (cm)");
+  hPRFc->SetTitleOffset(1.5,"X");
+  hPRFc->SetTitleOffset(1.5,"Y");
+  return hPRFc;
+}
+
+
+AliH2F * AliTPCPRF2D::GenerDrawDistHisto(Float_t x1, Float_t x2, Float_t y1, Float_t y2, Int_t Nx, Int_t Ny, Float_t  thr)
+{
+  //return histogram with distortion
+  const Float_t kminth=0.00001;
+  if (thr<kminth) thr=kminth;
+  char s[100]; 
+  //sprintf(s,"COG distortion of PRF (threshold=%2.2f)",thr); 
+  snprintf(s,100,"COG distortion of PRF (threshold=%2.2f)",thr); 
+  AliH2F * hPRFDist = new AliH2F("hDistortion",s,Nx,x1,x2,Ny,y1,y2);
+  Float_t dx=(x2-x1)/Float_t(Nx);
+  Float_t dy=(y2-y1)/Float_t(Ny) ;
+  Float_t x,y,z,ddx;
+  x=x1;
+  for ( Int_t i  = 0;i<=Nx;i++,x+=dx){
+    y=y1;
+    for(Int_t j  = 0;j<=Ny;j++,y+=dy)      
+      {
+       Float_t sumx=0;
+       Float_t sum=0;
+       for (Int_t k=-3;k<=3;k++)
+         {         
+           Float_t padx=Float_t(k)*fWidth;
+           z = GetPRF(x-padx,y); 
+           if (z>thr){
+             sum+=z;
+             sumx+=z*padx;
+           }   
+         };    
+       if (sum>kminth)  
+         {
+           ddx = (x-(sumx/sum));
+         }
+       else ddx=-1;
+       if (TMath::Abs(ddx)<10)         hPRFDist->SetCellContent(i,j,ddx);
+      }
+  }
+
+  hPRFDist->SetXTitle("pad direction (cm)");
+  hPRFDist->SetYTitle("pad row  direction (cm)");
+  hPRFDist->SetTitleOffset(1.5,"X");
+  hPRFDist->SetTitleOffset(1.5,"Y");
+  return hPRFDist;
+}  
+  
+
+
+
+
+void AliTPCPRF2D::DrawX(Float_t x1 ,Float_t x2,Float_t y1,Float_t y2, Int_t N)
+{ 
+  //
+  //draw pad response function at interval <x1,x2> at  given y position
+  //
+  if (N<0) return;
+  TCanvas  * c1 = new TCanvas("PRFX","Pad response function",700,900);
+  c1->cd();  
+  
   TPaveText * comment = new TPaveText(0.05,0.02,0.95,0.20,"NDC");
   comment->SetTextAlign(12);
   comment->SetFillColor(42);
-  TText *title = comment->AddText("Chevron pad parameters:");
-  title->SetTextSize(0.03);
-  sprintf(s,"Full height of pad:  %2.2f",fHeightFull);
-  comment->AddText(s);
-  sprintf(s,"Height of one chevron unit h:  %2.2f cm",2*fHeightS);
-  comment->AddText(s);
-  sprintf(s,"Width of one chevron unit  w:  %2.2f cm",fWidth);
-  comment->AddText(s);
-  sprintf(s,"Overlap factor:  %2.2f",fK*fHeightS/fWidth);
-  comment->AddText(s);
-  sprintf(s,"Y position:  %2.2f ",y);
-  comment->AddText(s);
-  sprintf(s,"Sigma x of original distribution: %2.2f ",forigsigmaX);
-  comment->AddText(s);  
-  sprintf(s,"Sigma y of original distribution: %2.2f ",forigsigmaY);
-  comment->AddText(s);    
-  sprintf(s,"Type of original distribution: %s ",fType);
-  comment->AddText(s); 
+  DrawComment(comment);  
   comment->Draw();
+  c1->cd(); 
+
+  TPad * pad2 = new TPad("pPRF","",0.05,0.22,0.95,0.95);
+  pad2->Divide(2,(N+1)/2);
+  pad2->Draw();
+  gStyle->SetOptFit(1);
+  gStyle->SetOptStat(1); 
+  for (Int_t i=0;i<N;i++){
+    char ch[200];
+    Float_t y;
+    if (N==1) y=y1;
+    else y = y1+i*(y2-y1)/Float_t(N-1);
+    pad2->cd(i+1);
+    TH1F * hPRFc =GenerDrawXHisto(x1, x2,y);
+    //sprintf(ch,"PRF at wire position: %2.3f",y);
+    snprintf(ch,40,"PRF at wire position: %2.3f",y);
+    hPRFc->SetTitle(ch);  
+    //sprintf(ch,"PRF %d",i);
+    snprintf(ch,15,"PRF %d",i);
+    hPRFc->SetName(ch);  
+     hPRFc->Fit("gaus");
+  }
 }
 
 
 
-void AliTPCPRF2D::Draw(Float_t x1 ,Float_t x2,Float_t y1, Float_t y2, 
-                 Bool_t inter, Int_t Nx, Int_t Ny)
+void AliTPCPRF2D::DrawPRF(Float_t x1 ,Float_t x2,Float_t y1, Float_t y2, Int_t Nx, Int_t Ny)
 { 
-  char s[100];
-  if (fGRF==0) return ;
+  //
+  //
   TCanvas  * c1 = new TCanvas("canPRF","Pad response function",700,900);
   c1->cd();
-  TPad * pad1 = new TPad("pad1PRF","",0.05,0.61,0.95,0.97,21);
-  pad1->Draw();
-  TPad * pad2 = new TPad("pad2PRF","",0.05,0.22,0.95,0.60,21);
-  pad2->Draw();
-
-  //  pad1->cd();  
-  //pad2->cd();
+  TPad * pad2 = new TPad("pad2PRF","",0.05,0.22,0.95,0.95);
+  pad2->Draw(); 
   gStyle->SetOptFit(1);
-  gStyle->SetOptStat(0); 
-  sprintf(s,"PRF response function for chevron pad");  
-  TH2F * hPRFc = new TH2F("hPRFc",s,Nx+1,x1,x2,Ny+1,y1,y2);
-  Float_t dx=(x2-x1)/Float_t(Nx);
-  Float_t dy=(y2-y1)/Float_t(Ny) ;
-  Float_t x,y,z;
-  //  Float_t y2;
-  for ( x = x1;x<=x2;x+=dx){
-    for(y = y1;y<=y2;y+=dy)
-      {
-       z = GetPRF(x,y,inter);
-       hPRFc->Fill(x,y,z);
-      };
-  }
-  pad1->cd();
-  fGRF->SetRange(x1,y1,x2,y2); 
-  fGRF->SetNpx(25);
-  fGRF->SetNpy(25); 
-  fGRF->Draw("lego2");
-  // hPRFo->Fit("gaus");
   gStyle->SetOptStat(1); 
+  TH2F * hPRFc = GenerDrawHisto(x1, x2, y1, y2, Nx,Ny);   
   pad2->cd();
-  hPRFc->Draw("lego2");
+  hPRFc->Draw("surf");
   c1->cd(); 
   TPaveText * comment = new TPaveText(0.05,0.02,0.95,0.20,"NDC");
   comment->SetTextAlign(12);
   comment->SetFillColor(42);
-  TText *title = comment->AddText("Chevron pad parameters:");
-  title->SetTextSize(0.03);
-  sprintf(s,"Full height of pad:  %2.2f",fHeightFull);
-  comment->AddText(s);
-  sprintf(s,"Height of one chevron unit h:  %2.2f cm",2*fHeightS);
-  comment->AddText(s);
-  sprintf(s,"Width of one chevron unit  w:  %2.2f cm",fWidth);
-  comment->AddText(s);
-  sprintf(s,"Overlap factor:  %2.2f",fK*fHeightS/fWidth);
-  comment->AddText(s); 
-  sprintf(s,"Sigma x of original distribution: %2.2f ",forigsigmaX);
-  comment->AddText(s);  
-  sprintf(s,"Sigma y of original distribution: %2.2f ",forigsigmaY);
-  comment->AddText(s);    
-  sprintf(s,"Type of original distribution: %s ",fType);
-  comment->AddText(s); 
+  DrawComment(comment);  
   comment->Draw();
 }
 
-void AliTPCPRF2D::DrawDist(Float_t x1 ,Float_t x2,Float_t y1, Float_t y2, 
-                 Bool_t inter, Int_t Nx, Int_t Ny, Float_t thr)
+void AliTPCPRF2D::DrawDist(Float_t x1 ,Float_t x2,Float_t y1, Float_t y2, Int_t Nx, Int_t Ny, Float_t thr)
 { 
-  const Float_t minth=0.00001;
-  if (thr<minth) thr=minth;
-  char s[100];
-  if (fGRF==0) return ;
+  //
+  //draw distortion of the COG method - for different threshold parameter
   TCanvas  * c1 = new TCanvas("padDistortion","COG distortion",700,900);
   c1->cd();
-  TPad * pad1 = new TPad("CHARGE","",0.05,0.61,0.95,0.97,21);
+  TPad * pad1 = new TPad("dist","",0.05,0.55,0.95,0.95,21);
   pad1->Draw();
-  TPad * pad2 = new TPad("dist","",0.05,0.22,0.95,0.60,21);
+  TPad * pad2 = new TPad("dist","",0.05,0.22,0.95,0.53,21);
   pad2->Draw();
-
-  //  pad1->cd();  
-  //pad2->cd();
   gStyle->SetOptFit(1);
   gStyle->SetOptStat(0); 
-  sprintf(s,"COG distortion (threshold=%2.2f)",thr);  
-  TH2F * hPRFDist = new TH2F("hDistortion",s,Nx+1,x1,x2,Ny+1,y1,y2);
-  Float_t dx=(x2-x1)/Float_t(Nx);
-  Float_t dy=(y2-y1)/Float_t(Ny) ;
-  Float_t x,y,z,ddx;
-  //  Float_t y2;
-  for ( x = x1;x<(x2+dx/2.);x+=dx)
-    for(y = y1;y<=(y2+dx/2.);y+=dy)
-      {
-       Float_t sumx=0;
-       Float_t sum=0;
-       for (Float_t padx=-fWidth;padx<(fWidth*1.1);padx+=fWidth)
-         {         
-           z = GetPRF(x-padx,y,inter);
-           if (z>thr){
-             sum+=z;
-             sumx+=z*padx;
-           }   
-         };    
-       if (sum>minth)  
-         {
-           ddx = (x-(sumx/sum));
-         }
-       else ddx=-1;
-       if (TMath::Abs(ddx)<10)         hPRFDist->Fill(x,y,ddx);
-      }
+  
+  AliH2F * hPRFDist = GenerDrawDistHisto(x1, x2, y1, y2, Nx,Ny,thr); 
+  
   pad1->cd();
-  fGRF->SetRange(x1,y1,x2,y2); 
-  fGRF->SetNpx(25);
-  fGRF->SetNpy(25); 
-  fGRF->Draw("lego2");
-  // hPRFo->Fit("gaus");
-  //  gStyle->SetOptStat(1); 
-  pad2->cd();
-  hPRFDist->Draw("lego2");
+  hPRFDist->Draw("surf");
+  Float_t distmax =hPRFDist->GetMaximum();
+  Float_t distmin =hPRFDist->GetMinimum();
+  gStyle->SetOptStat(1); 
   
+  TH1F * dist = hPRFDist->GetAmplitudes(distmin,distmax,distmin-1);
+  pad2->cd();
+  dist->Draw();
   c1->cd(); 
   TPaveText * comment = new TPaveText(0.05,0.02,0.95,0.20,"NDC");
   comment->SetTextAlign(12);
   comment->SetFillColor(42);
-  //  TText *title = comment->AddText("Distortion of COG method");
-  //  title->SetTextSize(0.03);
-  TText * title = comment->AddText("Chevron pad parameters:");
+  DrawComment(comment);  
+  comment->Draw();
+}
+
+void AliTPCPRF2D::DrawComment(TPaveText *comment)
+{
+  //
+  //function to write comment to picture 
+  
+  char s[100];
+  //draw comments to picture
+  TText * title = comment->AddText("Pad Response Function  parameters:");
   title->SetTextSize(0.03);
-  sprintf(s,"Full height of pad:  %2.2f",fHeightFull);
+  //sprintf(s,"Height of pad:  %2.2f cm",fHeightFull);
+  snprintf(s,100,"Height of pad:  %2.2f cm",fHeightFull);
   comment->AddText(s);
-  sprintf(s,"Height of one chevron unit h:  %2.2f cm",2*fHeightS);
+  //sprintf(s,"Width pad:  %2.2f cm",fWidth);
+  snprintf(s,100,"Width pad:  %2.2f cm",fWidth);
   comment->AddText(s);
-  sprintf(s,"Width of one chevron unit  w:  %2.2f cm",fWidth);
+  //sprintf(s,"Pad Angle:  %2.2f ",fPadAngle);
+  snprintf(s,100,"Pad Angle:  %2.2f ",fPadAngle);
   comment->AddText(s);
-  sprintf(s,"Overlap factor:  %2.2f",fK*fHeightS/fWidth);
-  comment->AddText(s); 
-  sprintf(s,"Sigma x of original distribution: %2.2f ",forigsigmaX);
-  comment->AddText(s);  
-  sprintf(s,"Sigma y of original distribution: %2.2f ",forigsigmaY);
-  comment->AddText(s);    
-  sprintf(s,"Type of original distribution: %s ",fType);
-  comment->AddText(s); 
-  comment->Draw();
   
+  if (TMath::Abs(fK)>0.0001){
+    //sprintf(s,"Height of one chevron unit h:  %2.2f cm",2*fHeightS);
+    snprintf(s,100,"Height of one chevron unit h:  %2.2f cm",2*fHeightS);
+    comment->AddText(s);
+    //sprintf(s,"Overlap factor:  %2.2f",fK);
+    snprintf(s,100,"Overlap factor:  %2.2f",fK);
+    comment->AddText(s); 
+  }
+
+  if (strncmp(fType,"User",3)==0){
+    //sprintf(s,"Charge distribution - user defined function  %s ",fGRF->GetTitle());
+    snprintf(s,100,"Charge distribution - user defined function  %s ",fGRF->GetTitle());
+    comment->AddText(s);  
+    //sprintf(s,"Sigma x of charge distribution: %2.2f ",fOrigSigmaX);
+    snprintf(s,100,"Sigma x of charge distribution: %2.2f ",fOrigSigmaX);  
+    comment->AddText(s);  
+    //sprintf(s,"Sigma y of charge distribution: %2.2f ",fOrigSigmaY);
+    snprintf(s,100,"Sigma y of charge distribution: %2.2f ",fOrigSigmaY);
+    comment->AddText(s); 
+  }
+  if (strncmp(fType,"Gauss",3)==0){
+    //sprintf(s,"Gauss charge distribution");
+    snprintf(s,100,"Gauss charge distribution");
+    comment->AddText(s);  
+    //sprintf(s,"Sigma x of charge distribution: %2.2f ",fOrigSigmaX);
+    snprintf(s,100,"Sigma x of charge distribution: %2.2f ",fOrigSigmaX);
+    comment->AddText(s);  
+    //sprintf(s,"Sigma y of charge distribution: %2.2f ",fOrigSigmaY);
+    snprintf(s,100,"Sigma y of charge distribution: %2.2f ",fOrigSigmaY);
+    comment->AddText(s); 
+  }
+  if (strncmp(fType,"Gati",3)==0){
+    //sprintf(s,"Gati charge distribution");
+    snprintf(s,100,"Gati charge distribution");
+    comment->AddText(s);  
+    //sprintf(s,"K3X of Gati : %2.2f ",fK3X);
+    snprintf(s,100,"K3X of Gati : %2.2f ",fK3X);
+    comment->AddText(s);  
+    //sprintf(s,"K3Y of Gati: %2.2f ",fK3Y);
+    snprintf(s,100,"K3Y of Gati: %2.2f ",fK3Y);
+    comment->AddText(s); 
+    //sprintf(s,"Wire to Pad Distance: %2.2f ",fPadDistance);
+    snprintf(s,100,"Wire to Pad Distance: %2.2f ",fPadDistance);
+    comment->AddText(s); 
+  }
+  if (strncmp(fType,"Cosh",3)==0){
+    //sprintf(s,"Cosh charge distribution");
+    snprintf(s,100,"Cosh charge distribution");
+    comment->AddText(s);  
+    //sprintf(s,"Sigma x of charge distribution: %2.2f ",fOrigSigmaX);
+    snprintf(s,100,"Sigma x of charge distribution: %2.2f ",fOrigSigmaX);
+    comment->AddText(s);  
+    //sprintf(s,"Sigma y of charge distribution: %2.2f ",fOrigSigmaY);
+    snprintf(s,100,"Sigma y of charge distribution: %2.2f ",fOrigSigmaY);
+    comment->AddText(s); 
+  }
+  //sprintf(s,"Normalisation: %2.2f ",fKNorm);
+  snprintf(s,100,"Normalisation: %2.2f ",fKNorm);
+  comment->AddText(s);    
 }