[u/mrichter/AliRoot.git] / STEER / AliTrackFitterRieman.cxx

/**************************************************************************
 * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
 *                                                                        *
 * Author: The ALICE Off-line Project.                                    *
 * Contributors are mentioned in the code where appropriate.              *
 *                                                                        *
 * Permission to use, copy, modify and distribute this software and its   *
 * documentation strictly for non-commercial purposes is hereby granted   *
 * without fee, provided that the above copyright notice appears in all   *
 * copies and that both the copyright notice and this permission notice   *
 * appear in the supporting documentation. The authors make no claims     *
 * about the suitability of this software for any purpose. It is          *
 * provided "as is" without express or implied warranty.                  *
 **************************************************************************/

/* $Id$ */

///////////////////////////////////////////////////////////////////////////////
//
// Class to the track points on the Riemann sphere. Inputs are
// the set of id's (volids) of the volumes in which residuals are
// calculated to construct a chi2 function to be minimized during 
// the alignment procedures. For the moment the track extrapolation is 
// taken at the space-point reference plane. The reference plane is
// found using the covariance matrix of the point
// (assuming sigma(x)=0 at the reference coordinate system.
//
// Internal usage of AliRieman class for minimization
//
//////////////////////////////////////////////////////////////////////////////

#include <TArrayI.h>
#include <TLinearFitter.h>
#include <TMath.h>
#include <TMatrixD.h>
#include <TMatrixDSym.h>
#include <TRandom.h>
#include <TTreeStream.h>

#include "AliLog.h"
#include "AliLog.h"
#include "AliRieman.h"
#include "AliTrackFitterRieman.h"

ClassImp(AliTrackFitterRieman)


AliTrackFitterRieman::AliTrackFitterRieman():
  AliTrackFitter(),
  fBCorrection(kFALSE),
  fAlpha(0.),
  fNUsed(0),
  fConv(kFALSE),
  fMaxDelta(3),
  fRieman(new AliRieman(10000)),  // allocate rieman
  fMinPointRadius(2.),
  fMaxPointRadius(500.),
  fDebugStream(new TTreeSRedirector("RiemanAlignDebug.root"))
{
  //
  // default constructor
  //
}


AliTrackFitterRieman::AliTrackFitterRieman(AliTrackPointArray *array, Bool_t owner):
  AliTrackFitter(array,owner),
  fBCorrection(kFALSE),
  fAlpha(0.),
  fNUsed(0),
  fConv(kFALSE),
  fMaxDelta(3),
  fRieman(new AliRieman(10000)),  //allocate rieman
  fMinPointRadius(2.),
  fMaxPointRadius(500.),
  fDebugStream(0)
{
  //
  // Constructor
  //
  if (AliLog::GetDebugLevel("","AliTrackFitterRieman")) fDebugStream = new TTreeSRedirector("RiemanAlignDebug.root");
}

AliTrackFitterRieman::AliTrackFitterRieman(const AliTrackFitterRieman &rieman):
  AliTrackFitter(rieman),
  fBCorrection(rieman.fBCorrection),
  fAlpha(rieman.fAlpha),
  fNUsed(rieman.fNUsed),
  fConv(rieman.fConv),
  fMaxDelta(rieman.fMaxDelta),
  fRieman(new AliRieman(*(rieman.fRieman))),
  fMinPointRadius(rieman.fMinPointRadius),
  fMaxPointRadius(rieman.fMaxPointRadius),
  fDebugStream(0)
{
  //
  // copy constructor
  //
  if (AliLog::GetDebugLevel("","AliTrackFitterRieman")) fDebugStream = new TTreeSRedirector("RiemanAlignDebug.root");
}

//_____________________________________________________________________________
AliTrackFitterRieman &AliTrackFitterRieman::operator =(const AliTrackFitterRieman& rieman)
{
  //
  // Assignment operator
  //
  if(this==&rieman) return *this;
  ((AliTrackFitter *)this)->operator=(rieman);

  fBCorrection = rieman.fBCorrection;
  fAlpha  = rieman.fAlpha;
  fNUsed  = rieman.fNUsed;
  fConv   = rieman.fConv;
  fMaxDelta = rieman.fMaxDelta;
  fRieman = new AliRieman(*(rieman.fRieman));
  fMinPointRadius = rieman.fMinPointRadius;
  fMaxPointRadius = rieman.fMaxPointRadius;
  fDebugStream = 0;
  if (AliLog::GetDebugLevel("","AliTrackFitterRieman")) fDebugStream = new TTreeSRedirector("RiemanAlignDebug.root");
  return *this;
}


AliTrackFitterRieman::~AliTrackFitterRieman(){
  //
  //
  //
  delete fRieman;
  delete fDebugStream;
}

void AliTrackFitterRieman::Reset()
{
  // Reset the track parameters and
  // rieman sums
  //
  AliTrackFitter::Reset();
  fRieman->Reset();
  fAlpha = 0.;
  fNUsed = 0;
  fConv =kFALSE;
}

Bool_t AliTrackFitterRieman::Fit(const TArrayI *volIds,const TArrayI *volIdsFit,
				 AliGeomManager::ELayerID layerRangeMin,
			 AliGeomManager::ELayerID layerRangeMax)
{
  // Fit the track points. The method takes as an input
  // the set of id's (volids) of the volumes in which
  // one wants to calculate the residuals.
  // The following parameters are used to define the
  // range of volumes to be used in the fitting
  // As a result two AliTrackPointArray's obects are filled.
  // The first one contains the space points with
  // volume id's from volids list. The second array of points represents
  // the track extrapolations corresponding to the space points
  // in the first array. The two arrays can be used to find
  // the residuals in the volids and consequently construct a
  // chi2 function to be minimized during the alignment
  // procedures. For the moment the track extrapolation is taken
  // at the space-point reference plane. The reference plane is
  // found using the covariance matrix of the point
  // (assuming sigma(x)=0 at the reference coordinate system.
  Int_t debugLevel = AliLog::GetDebugLevel("","AliTrackFitterRieman");
  
  //  Float_t debugRatio = 1./(1.+debugLevel);
  Float_t debugRatio = debugLevel? 1.0/debugLevel : 1.0;

  Int_t npoints = fPoints->GetNPoints();
  if ( npoints<fMinNPoints) return kFALSE;
  //
  // fast count points
  if (volIdsFit != 0x0) {
    Int_t countFit = 0;
    Int_t countPoint = 0;
    for (Int_t ipoint = 0; ipoint < npoints; ipoint++) {
      if (FindVolId(volIds,fPoints->GetVolumeID()[ipoint]))
	countPoint++;
      if (volIdsFit != 0x0) {
	if (FindVolId(volIdsFit,fPoints->GetVolumeID()[ipoint]))
	  countFit++;
      }
    }
    if (countPoint==0) return kFALSE;
    if ((countFit<fMinNPoints) && (volIdsFit != 0x0)) return kFALSE;
  }
  //

  Reset();

  if (fPoints && AliLog::GetDebugLevel("","AliTrackFitterRieman")>1&& gRandom->Rndm()<debugRatio){
    Int_t nVol    = volIds->GetSize();
    Int_t nVolFit = volIdsFit->GetSize();
    Int_t volId  = volIds->At(0);    
    (*fDebugStream)<<"PInput"<<
      "NPoints="<<npoints<<    // number of points
      "VolId="<<volId<<        // first vol ID
      "NVol="<<nVol<<          // number of volumes 
      "NvolFit="<<nVolFit<<    // number of volumes to fit
      "fPoints.="<<fPoints<<   // input points
      "\n";
  }

  Bool_t isAlphaCalc = kFALSE;
  AliTrackPoint p,plocal;
//   fPoints->GetPoint(p,0);
//   fAlpha = TMath::ATan2(p.GetY(),p.GetX());

  Int_t npVolId = 0;
  fNUsed = 0;
  Int_t *pindex = new Int_t[npoints];
  for (Int_t ipoint = 0; ipoint < npoints; ipoint++)
    {
      fPoints->GetPoint(p,ipoint);
      UShort_t iVolId = p.GetVolumeID();
      if (FindVolId(volIds,iVolId)) {
	pindex[npVolId] = ipoint;
	npVolId++;
      }
      if (volIdsFit != 0x0) {
	if (!FindVolId(volIdsFit,iVolId)) continue;
      }
      else {
	if (iVolId < AliGeomManager::LayerToVolUID(layerRangeMin,0) ||
	    iVolId > AliGeomManager::LayerToVolUID(layerRangeMax,
						AliGeomManager::LayerSize(layerRangeMax))) continue;
      }
      if (!isAlphaCalc) {
	fAlpha = p.GetAngle();
	isAlphaCalc = kTRUE;
      }
      plocal = p.Rotate(fAlpha);
      if (TMath::Abs(plocal.GetX())>fMaxPointRadius || TMath::Abs(plocal.GetX())<fMinPointRadius || plocal.GetCov()[3]<=0 ||plocal.GetCov()[5]<=0 ){
	printf("<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<</n");
	p.Dump();
	plocal.Dump();
	printf("Problematic point\n");	
	printf("<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<</n");
      }else{
	AddPoint(plocal.GetX(),plocal.GetY(),plocal.GetZ(),
		 TMath::Sqrt(plocal.GetCov()[3]),TMath::Sqrt(plocal.GetCov()[5]));
      }
      // fNUsed++;  AddPoint should be responsible
    }

  if (npVolId == 0 || fNUsed < fMinNPoints) {
    delete [] pindex;
    return kFALSE;
  }

  Update();
 
  if (!fConv) {
    delete [] pindex;
    return kFALSE;
  }

  if ((fParams[0] == 0) ||
      ((-fParams[2]*fParams[0]+fParams[1]*fParams[1]+1) <= 0)) {
    delete [] pindex;
    return kFALSE;
  }


  if (fNUsed < fMinNPoints) {
    delete [] pindex;
    return kFALSE;
  }

  fPVolId = new AliTrackPointArray(npVolId);
  fPTrack = new AliTrackPointArray(npVolId);
  AliTrackPoint p2;
  for (Int_t ipoint = 0; ipoint < npVolId; ipoint++)
    {
      Int_t index = pindex[ipoint];
      fPoints->GetPoint(p,index);
      if (GetPCA(p,p2) && (
	  TMath::Abs(p.GetX()-p2.GetX())<fMaxDelta && 
	  TMath::Abs(p.GetY()-p2.GetY())<fMaxDelta &&
	  TMath::Abs(p.GetZ()-p2.GetZ())<fMaxDelta
	  )) {
	Float_t xyz[3],xyz2[3];
	p.GetXYZ(xyz); p2.GetXYZ(xyz2);
	//	printf("residuals %f %d %d %f %f %f %f %f %f\n",fChi2,fNUsed,fConv,xyz[0],xyz[1],xyz[2],xyz2[0]-xyz[0],xyz2[1]-xyz[1],xyz2[2]-xyz[2]);	
	fPVolId->AddPoint(ipoint,&p);
	fPTrack->AddPoint(ipoint,&p2);
      }else{
	// what should be default bahavior -  
	delete [] pindex;
	delete fPVolId;
	delete fPTrack;
	fPVolId =0;
	fPTrack =0;
	return kFALSE;
      }
    }  
  
  if (AliLog::GetDebugLevel("","AliTrackFitterRieman")>0 && gRandom->Rndm()<debugRatio){
    //
    // Debug Info
    //
    AliTrackPointArray *lPVolId = new AliTrackPointArray(npVolId);
    AliTrackPointArray *lPTrack = new AliTrackPointArray(npVolId);
    AliTrackPointArray *lPTrackE = new AliTrackPointArray(npVolId);
    AliRieman * residual = fRieman->MakeResiduals();
    for (Int_t ipoint = 0; ipoint < npVolId; ipoint++){
      AliTrackPoint p0, p0local;      
      AliTrackPoint pFit, pFitlocal, pFitLocalE;      
      fPVolId->GetPoint(p0,ipoint);
      Float_t lAngle = p0.GetAngle();
      p0local= p0.MasterToLocal();
      fPTrack->GetPoint(pFit,ipoint);
      pFitlocal= pFit.Rotate(lAngle);
      //
      Float_t xyz[3], cov[6];
      xyz[0] = pFitlocal.GetX();
      xyz[1] = pFitlocal.GetY();
      xyz[2] = pFitlocal.GetZ();
      for (Int_t icov=0; icov<6; icov++) cov[icov]=0;
      cov[3] = GetErrY2at(xyz[0]);
      cov[5] = GetErrZ2at(xyz[0]);      
      pFitLocalE.SetXYZ(xyz,cov);
      //
      lPVolId->AddPoint(ipoint,&p0local);
      lPTrack->AddPoint(ipoint,&pFitlocal);
      lPTrackE->AddPoint(ipoint,&pFitLocalE);
    }      
    //
    // debug info
    //
    Int_t nVol    = volIds->GetSize();
    Int_t nVolFit = volIdsFit->GetSize();
    Int_t volId   = volIds->At(0);   
    Int_t modId   =0;
    Int_t layer   =  AliGeomManager::VolUIDToLayer(volId,modId);
    Int_t volIdFit   = volIdsFit->At(0);   
    Int_t modIdFit   =0;
    Int_t layerFit   =  AliGeomManager::VolUIDToLayer(volIdFit,modIdFit);
    
    (*fDebugStream)<<"Fit"<<
      "VolId="<<volId<<        // volume ID
      "Layer="<<layer<<        // layer ID
      "Module="<<modId<<       // module ID
      "LayerFit="<<layerFit<<        // layer ID fit
      "ModuleFit="<<modIdFit<<       // module ID fit
      "NVol="<<nVol<<          // number of volumes 
      "NvolFit="<<nVolFit<<    // number of volumes to fit
      "Points0.="<<fPVolId<<    // original points
      "Points1.="<<fPTrack<<    // fitted points 
      "LPoints0.="<<lPVolId<<   // original points - local frame
      "LPoints1.="<<lPTrack<<   // fitted points   - local frame      
      "LPointsE.="<<lPTrackE<<   // fitted points with ext error - local frame      
      "Rieman.="<<this<<        // original rieman fit
      "Res.="<<residual<<       // residuals of rieman fit  
      "\n";
    delete lPVolId;
    delete lPTrack;
    delete residual;
  }

  delete [] pindex;
  return kTRUE;
}


void AliTrackFitterRieman::AddPoint(Float_t x, Float_t y, Float_t z, Float_t sy, Float_t sz)
{
  //
  // add point to rieman fitter
  //
  fRieman->AddPoint(x,y,z,sy,sz);
  fNUsed = fRieman->GetN();
}


Bool_t AliTrackFitterRieman::Update(){
  //
  // 
  //
  fRieman->Update();
  fConv = kFALSE;
  if (fRieman->IsValid()){
    for (Int_t ipar=0; ipar<6; ipar++){
      fParams[ipar] = fRieman->GetParam()[ipar];
    }
    fChi2  =  fRieman->GetChi2();
    fNdf   =  fRieman->GetN()- 2;
    fNUsed =  fRieman->GetN();
    fConv = kTRUE;
  }
  //
  //
  //
  TLinearFitter fitY(3,"pol2");
  TLinearFitter fitZ(3,"pol2");
  for (Int_t ip=0; ip<fRieman->GetN();ip++){
    Double_t x = fRieman->GetX()[ip]; 
    fitY.AddPoint(&x,fRieman->GetY()[ip]-fRieman->GetYat(x),1);
    fitZ.AddPoint(&x,fRieman->GetZ()[ip]-fRieman->GetZat(x),1);    
  }
  fitY.Eval();
  fitZ.Eval();
  for (Int_t iparam=0; iparam<3; iparam++){
    fCorrY[iparam]=fitY.GetParameter(iparam);
    fCorrZ[iparam]=fitZ.GetParameter(iparam);
  }
  fCorrY[3]=fitY.GetChisquare()/Float_t(fRieman->GetN()-3);   
  fCorrZ[3]=fitZ.GetChisquare()/Float_t(fRieman->GetN()-3);

  return kTRUE;
}


//_____________________________________________________________________________
Bool_t AliTrackFitterRieman::GetPCA(const AliTrackPoint &p, AliTrackPoint &p2) const
{
  //
  // Get the closest to a given spacepoint track trajectory point
  // Look for details in the description of the Fit() method
  //
  if (!fConv) return kFALSE;

  // First X and Y coordinates
  Double_t sin = TMath::Sin(fAlpha);
  Double_t cos = TMath::Cos(fAlpha);
  //  fParam[0]  = 1/y0
  //  fParam[1]  = -x0/y0
  //  fParam[2]  = - (R^2 - x0^2 - y0^2)/y0
  if (fParams[0] == 0) return kFALSE;
  // Track parameters in the global coordinate system
  Double_t x0 = -fParams[1]/fParams[0]*cos -         1./fParams[0]*sin;
  Double_t y0 =          1./fParams[0]*cos - fParams[1]/fParams[0]*sin;
  if ((-fParams[2]*fParams[0]+fParams[1]*fParams[1]+1) <= 0) return kFALSE;
  Double_t r  = TMath::Sqrt(-fParams[2]*fParams[0]+fParams[1]*fParams[1]+1)/
                fParams[0];

  // Define space-point refence plane
  Double_t alphap = p.GetAngle();
  Double_t sinp = TMath::Sin(alphap);
  Double_t cosp = TMath::Cos(alphap);
  Double_t x  = p.GetX()*cosp + p.GetY()*sinp;
  Double_t y  = p.GetY()*cosp - p.GetX()*sinp;
  Double_t x0p= x0*cosp + y0*sinp;
  Double_t y0p= y0*cosp - x0*sinp;
  if ((r*r - (x-x0p)*(x-x0p))<0) {
    AliWarning(Form("Track extrapolation failed ! (Track radius = %f, track circle x = %f, space-point x = %f, reference plane angle = %f\n",r,x0p,x,alphap));
    return kFALSE;
  }
  Double_t temp = TMath::Sqrt(r*r - (x-x0p)*(x-x0p));
  Double_t y1 = y0p + temp;
  Double_t y2 = y0p - temp;
  Double_t yprime = y1;
  if(TMath::Abs(y2-y) < TMath::Abs(y1-y)) yprime = y2;

  // Back to the global coordinate system
  Double_t xsecond = x*cosp - yprime*sinp;
  Double_t ysecond = yprime*cosp + x*sinp;

  // Now Z coordinate and track angles
  Double_t x2 = xsecond*cos + ysecond*sin;
  Double_t zsecond = GetZat(x2);
  Double_t dydx = GetDYat(x2);
  Double_t dzdx = GetDZat(x2);

  // Fill the cov matrix of the track extrapolation point
  Double_t cov[6] = {0,0,0,0,0,0};
  Double_t sigmax = 100*100.;
  cov[0] = sigmax;           cov[1] = sigmax*dydx;      cov[2] = sigmax*dzdx;
  cov[3] = sigmax*dydx*dydx; cov[4] = sigmax*dydx*dzdx;
  cov[5] = sigmax*dzdx*dzdx;

  Double_t sigmay2 = GetErrY2at(x2);
  Double_t sigmaz2 = GetErrZ2at(x2);
  cov[3] += sigmay2;
  cov[5] += sigmaz2;
   

  Float_t  newcov[6];
  newcov[0] = cov[0]*cos*cos-
            2*cov[1]*sin*cos+
              cov[3]*sin*sin;
  newcov[1] = cov[1]*(cos*cos-sin*sin)-
             (cov[3]-cov[0])*sin*cos;
  newcov[2] = cov[2]*cos-
              cov[4]*sin;
  newcov[3] = cov[0]*sin*sin+
            2*cov[1]*sin*cos+
              cov[3]*cos*cos;
  newcov[4] = cov[4]*cos+
              cov[2]*sin;
  newcov[5] = cov[5];

  p2.SetXYZ(xsecond,ysecond,zsecond,newcov);
  Int_t debugLevel = AliLog::GetDebugLevel("","AliTrackFitterRieman");
  Float_t debugRatio = 1./(1.+debugLevel);
  if (AliLog::GetDebugLevel("","AliTrackFitterRieman")>0 && gRandom->Rndm()<debugRatio){
    AliTrackPoint lp0(p);
    AliTrackPoint lp2(p2);
    AliTrackPoint localp0(p);
    AliTrackPoint localp2(p2);
    Float_t lAngle = lp0.GetAngle();
    localp0 = localp0.Rotate(lAngle);
    localp2 = localp2.Rotate(lAngle);

    (*fDebugStream)<<"PCA"<<
      "P0.="<<&lp0<<  //global position
      "P2.="<<&lp2<<
      "LP0.="<<&localp0<<  //local position
      "LP2.="<<&localp2<<
      "\n";
  }
  return kTRUE;
}

Double_t AliTrackFitterRieman::GetYat(Double_t x) const  {
  //
  // get y position at given point 
  //
  Double_t correction=0;
  if (fBCorrection){ // systematic effect correction
    correction  =  fCorrY[0]+fCorrY[1]*x +fCorrY[2]*x*x;
  }
  return fRieman->GetYat(x)+correction;
}

Double_t AliTrackFitterRieman::GetZat(Double_t x) const  {
  //
  // get z position at given point 
  //
  Double_t correction=0;
  if (fBCorrection){ // systematic effect correction
    correction  =  fCorrZ[0]+fCorrZ[1]*x +fCorrZ[2]*x*x;
  }
  return fRieman->GetZat(x)+correction;
}

Double_t AliTrackFitterRieman::GetErrY2at(Double_t x) const {
  //
  // get estimate of extrapolation error
  //
  Double_t error = fRieman->GetErrY(x);
  Double_t correction=0;
  if (fBCorrection){ // everestimate error due systematic effect
    error      *=fCorrY[3];
    correction  =  fCorrY[0]+fCorrY[1]*x +fCorrY[2]*x*x;
    correction *=correction;
  }
  return TMath::Sqrt(error+correction);
}

Double_t AliTrackFitterRieman::GetErrZ2at(Double_t x) const {
  //
  // get estimate of extrapolation error
  //
  Double_t error = fRieman->GetErrZ(x)*fCorrZ[3];
  Double_t correction=0;
  if (fBCorrection){  
     error    *=  fCorrZ[3];
    correction =  fCorrZ[0]+fCorrZ[1]*x +fCorrZ[2]*x*x;
    correction*=  correction;
  }
  return TMath::Sqrt(error+correction);
}

void AliTrackFitterRieman::SetParam(Int_t i, Double_t par) {
  if (i<0 || i>5) return;
  fParams[i]=par;
  fRieman->GetParam()[i]=par;
}
Commit	Line	Data
6b6cba33	1	/**************************************************************************
	2	* Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
	3	* *
	4	* Author: The ALICE Off-line Project. *
	5	* Contributors are mentioned in the code where appropriate. *
	6	* *
	7	* Permission to use, copy, modify and distribute this software and its *
	8	* documentation strictly for non-commercial purposes is hereby granted *
	9	* without fee, provided that the above copyright notice appears in all *
	10	* copies and that both the copyright notice and this permission notice *
	11	* appear in the supporting documentation. The authors make no claims *
	12	* about the suitability of this software for any purpose. It is *
	13	* provided "as is" without express or implied warranty. *
	14	**************************************************************************/
	15
	16	/* $Id$ */
	17
	18	///////////////////////////////////////////////////////////////////////////////
	19	//
	20	// Class to the track points on the Riemann sphere. Inputs are
	21	// the set of id's (volids) of the volumes in which residuals are
	22	// calculated to construct a chi2 function to be minimized during
	23	// the alignment procedures. For the moment the track extrapolation is
	24	// taken at the space-point reference plane. The reference plane is
	25	// found using the covariance matrix of the point
	26	// (assuming sigma(x)=0 at the reference coordinate system.
	27	//
8849da04	28	// Internal usage of AliRieman class for minimization
8849da04	29	//
6b6cba33	30	//////////////////////////////////////////////////////////////////////////////
6b6cba33	31
3010c308	32	#include <TArrayI.h>
	33	#include <TLinearFitter.h>
	34	#include <TMath.h>
	35	#include <TMatrixD.h>
	36	#include <TMatrixDSym.h>
	37	#include <TRandom.h>
	38	#include <TTreeStream.h>
	39
24d4520d	40	#include "AliLog.h"
8849da04	41	#include "AliLog.h"
3010c308	42	#include "AliRieman.h"
3010c308	43	#include "AliTrackFitterRieman.h"
98937d93	44
	45	ClassImp(AliTrackFitterRieman)
	46
8849da04	47
98937d93	48	AliTrackFitterRieman::AliTrackFitterRieman():
75e3794b	49	AliTrackFitter(),
dfce6628	50	fBCorrection(kFALSE),
75e3794b	51	fAlpha(0.),
	52	fNUsed(0),
	53	fConv(kFALSE),
	54	fMaxDelta(3),
	55	fRieman(new AliRieman(10000)), // allocate rieman
d4af2e1d	56	fMinPointRadius(2.),
d4af2e1d	57	fMaxPointRadius(500.),
75e3794b	58	fDebugStream(new TTreeSRedirector("RiemanAlignDebug.root"))
98937d93	59	{
	60	//
	61	// default constructor
	62	//
98937d93	63	}
	64
	65
	66	AliTrackFitterRieman::AliTrackFitterRieman(AliTrackPointArray *array, Bool_t owner):
75e3794b	67	AliTrackFitter(array,owner),
dfce6628	68	fBCorrection(kFALSE),
75e3794b	69	fAlpha(0.),
	70	fNUsed(0),
	71	fConv(kFALSE),
	72	fMaxDelta(3),
	73	fRieman(new AliRieman(10000)), //allocate rieman
d4af2e1d	74	fMinPointRadius(2.),
d4af2e1d	75	fMaxPointRadius(500.),
75e3794b	76	fDebugStream(0)
98937d93	77	{
	78	//
	79	// Constructor
	80	//
8849da04	81	if (AliLog::GetDebugLevel("","AliTrackFitterRieman")) fDebugStream = new TTreeSRedirector("RiemanAlignDebug.root");
98937d93	82	}
	83
	84	AliTrackFitterRieman::AliTrackFitterRieman(const AliTrackFitterRieman &rieman):
75e3794b	85	AliTrackFitter(rieman),
dfce6628	86	fBCorrection(rieman.fBCorrection),
75e3794b	87	fAlpha(rieman.fAlpha),
	88	fNUsed(rieman.fNUsed),
	89	fConv(rieman.fConv),
	90	fMaxDelta(rieman.fMaxDelta),
	91	fRieman(new AliRieman(*(rieman.fRieman))),
d4af2e1d	92	fMinPointRadius(rieman.fMinPointRadius),
d4af2e1d	93	fMaxPointRadius(rieman.fMaxPointRadius),
75e3794b	94	fDebugStream(0)
98937d93	95	{
	96	//
	97	// copy constructor
	98	//
75e3794b	99	if (AliLog::GetDebugLevel("","AliTrackFitterRieman")) fDebugStream = new TTreeSRedirector("RiemanAlignDebug.root");
98937d93	100	}
	101
	102	//_____________________________________________________________________________
	103	AliTrackFitterRieman &AliTrackFitterRieman::operator =(const AliTrackFitterRieman& rieman)
	104	{
6b6cba33	105	//
6b6cba33	106	// Assignment operator
98937d93	107	//
	108	if(this==&rieman) return *this;
	109	((AliTrackFitter *)this)->operator=(rieman);
	110
dfce6628	111	fBCorrection = rieman.fBCorrection;
8849da04	112	fAlpha = rieman.fAlpha;
	113	fNUsed = rieman.fNUsed;
	114	fConv = rieman.fConv;
186e6ced	115	fMaxDelta = rieman.fMaxDelta;
8849da04	116	fRieman = new AliRieman(*(rieman.fRieman));
d4af2e1d	117	fMinPointRadius = rieman.fMinPointRadius;
d4af2e1d	118	fMaxPointRadius = rieman.fMaxPointRadius;
75e3794b	119	fDebugStream = 0;
75e3794b	120	if (AliLog::GetDebugLevel("","AliTrackFitterRieman")) fDebugStream = new TTreeSRedirector("RiemanAlignDebug.root");
98937d93	121	return *this;
	122	}
	123
8849da04	124
	125	AliTrackFitterRieman::~AliTrackFitterRieman(){
	126	//
	127	//
	128	//
	129	delete fRieman;
	130	delete fDebugStream;
	131	}
	132
98937d93	133	void AliTrackFitterRieman::Reset()
	134	{
	135	// Reset the track parameters and
	136	// rieman sums
6b6cba33	137	//
98937d93	138	AliTrackFitter::Reset();
8849da04	139	fRieman->Reset();
98937d93	140	fAlpha = 0.;
46ae650f	141	fNUsed = 0;
98937d93	142	fConv =kFALSE;
	143	}
	144
cc345ce3	145	Bool_t AliTrackFitterRieman::Fit(const TArrayI volIds,const TArrayI volIdsFit,
25be1e5c	146	AliGeomManager::ELayerID layerRangeMin,
25be1e5c	147	AliGeomManager::ELayerID layerRangeMax)
98937d93	148	{
98937d93	149	// Fit the track points. The method takes as an input
cc345ce3	150	// the set of id's (volids) of the volumes in which
	151	// one wants to calculate the residuals.
	152	// The following parameters are used to define the
98937d93	153	// range of volumes to be used in the fitting
	154	// As a result two AliTrackPointArray's obects are filled.
	155	// The first one contains the space points with
cc345ce3	156	// volume id's from volids list. The second array of points represents
cc345ce3	157	// the track extrapolations corresponding to the space points
98937d93	158	// in the first array. The two arrays can be used to find
cc345ce3	159	// the residuals in the volids and consequently construct a
98937d93	160	// chi2 function to be minimized during the alignment
98937d93	161	// procedures. For the moment the track extrapolation is taken
cc345ce3	162	// at the space-point reference plane. The reference plane is
	163	// found using the covariance matrix of the point
	164	// (assuming sigma(x)=0 at the reference coordinate system.
dfce6628	165	Int_t debugLevel = AliLog::GetDebugLevel("","AliTrackFitterRieman");
d9e9045c	166
	167	// Float_t debugRatio = 1./(1.+debugLevel);
	168	Float_t debugRatio = debugLevel? 1.0/debugLevel : 1.0;
98937d93	169
98937d93	170	Int_t npoints = fPoints->GetNPoints();
dfce6628	171	if ( npoints<fMinNPoints) return kFALSE;
	172	//
	173	// fast count points
f8ad955c	174	if (volIdsFit != 0x0) {
	175	Int_t countFit = 0;
	176	Int_t countPoint = 0;
	177	for (Int_t ipoint = 0; ipoint < npoints; ipoint++) {
	178	if (FindVolId(volIds,fPoints->GetVolumeID()[ipoint]))
	179	countPoint++;
	180	if (volIdsFit != 0x0) {
	181	if (FindVolId(volIdsFit,fPoints->GetVolumeID()[ipoint]))
	182	countFit++;
	183	}
	184	}
	185	if (countPoint==0) return kFALSE;
	186	if ((countFit<fMinNPoints) && (volIdsFit != 0x0)) return kFALSE;
dfce6628	187	}
dfce6628	188	//
	189
	190	Reset();
	191
	192	if (fPoints && AliLog::GetDebugLevel("","AliTrackFitterRieman")>1&& gRandom->Rndm()<debugRatio){
8849da04	193	Int_t nVol = volIds->GetSize();
	194	Int_t nVolFit = volIdsFit->GetSize();
	195	Int_t volId = volIds->At(0);
	196	(*fDebugStream)<<"PInput"<<
	197	"NPoints="<<npoints<< // number of points
	198	"VolId="<<volId<< // first vol ID
	199	"NVol="<<nVol<< // number of volumes
	200	"NvolFit="<<nVolFit<< // number of volumes to fit
	201	"fPoints.="<<fPoints<< // input points
	202	"\n";
	203	}
98937d93	204
cc345ce3	205	Bool_t isAlphaCalc = kFALSE;
46ae650f	206	AliTrackPoint p,plocal;
cc345ce3	207	// fPoints->GetPoint(p,0);
cc345ce3	208	// fAlpha = TMath::ATan2(p.GetY(),p.GetX());
98937d93	209
98937d93	210	Int_t npVolId = 0;
46ae650f	211	fNUsed = 0;
98937d93	212	Int_t *pindex = new Int_t[npoints];
	213	for (Int_t ipoint = 0; ipoint < npoints; ipoint++)
	214	{
	215	fPoints->GetPoint(p,ipoint);
	216	UShort_t iVolId = p.GetVolumeID();
cc345ce3	217	if (FindVolId(volIds,iVolId)) {
98937d93	218	pindex[npVolId] = ipoint;
	219	npVolId++;
	220	}
cc345ce3	221	if (volIdsFit != 0x0) {
cc345ce3	222	if (!FindVolId(volIdsFit,iVolId)) continue;
46ae650f	223	}
46ae650f	224	else {
25be1e5c	225	if (iVolId < AliGeomManager::LayerToVolUID(layerRangeMin,0) \|\|
	226	iVolId > AliGeomManager::LayerToVolUID(layerRangeMax,
	227	AliGeomManager::LayerSize(layerRangeMax))) continue;
46ae650f	228	}
cc345ce3	229	if (!isAlphaCalc) {
	230	fAlpha = p.GetAngle();
	231	isAlphaCalc = kTRUE;
	232	}
46ae650f	233	plocal = p.Rotate(fAlpha);
d4af2e1d	234	if (TMath::Abs(plocal.GetX())>fMaxPointRadius \|\| TMath::Abs(plocal.GetX())<fMinPointRadius \|\| plocal.GetCov()[3]<=0 \|\|plocal.GetCov()[5]<=0 ){
8849da04	235	printf("<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<</n");
	236	p.Dump();
	237	plocal.Dump();
	238	printf("Problematic point\n");
	239	printf("<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<</n");
186e6ced	240	}else{
	241	AddPoint(plocal.GetX(),plocal.GetY(),plocal.GetZ(),
	242	TMath::Sqrt(plocal.GetCov()[3]),TMath::Sqrt(plocal.GetCov()[5]));
8849da04	243	}
8849da04	244	// fNUsed++; AddPoint should be responsible
98937d93	245	}
98937d93	246
8849da04	247	if (npVolId == 0 \|\| fNUsed < fMinNPoints) {
98937d93	248	delete [] pindex;
	249	return kFALSE;
	250	}
	251
	252	Update();
cc345ce3	253
98937d93	254	if (!fConv) {
	255	delete [] pindex;
	256	return kFALSE;
	257	}
	258
	259	if ((fParams[0] == 0) \|\|
	260	((-fParams[2]fParams[0]+fParams[1]fParams[1]+1) <= 0)) {
	261	delete [] pindex;
	262	return kFALSE;
	263	}
	264
cc345ce3	265
	266	if (fNUsed < fMinNPoints) {
	267	delete [] pindex;
	268	return kFALSE;
	269	}
	270
46ae650f	271	fPVolId = new AliTrackPointArray(npVolId);
46ae650f	272	fPTrack = new AliTrackPointArray(npVolId);
98937d93	273	AliTrackPoint p2;
	274	for (Int_t ipoint = 0; ipoint < npVolId; ipoint++)
	275	{
	276	Int_t index = pindex[ipoint];
	277	fPoints->GetPoint(p,index);
186e6ced	278	if (GetPCA(p,p2) && (
	279	TMath::Abs(p.GetX()-p2.GetX())<fMaxDelta &&
	280	TMath::Abs(p.GetY()-p2.GetY())<fMaxDelta &&
	281	TMath::Abs(p.GetZ()-p2.GetZ())<fMaxDelta
	282	)) {
cc345ce3	283	Float_t xyz[3],xyz2[3];
cc345ce3	284	p.GetXYZ(xyz); p2.GetXYZ(xyz2);
186e6ced	285	// printf("residuals %f %d %d %f %f %f %f %f %f\n",fChi2,fNUsed,fConv,xyz[0],xyz[1],xyz[2],xyz2[0]-xyz[0],xyz2[1]-xyz[1],xyz2[2]-xyz[2]);
46ae650f	286	fPVolId->AddPoint(ipoint,&p);
46ae650f	287	fPTrack->AddPoint(ipoint,&p2);
8849da04	288	}else{
	289	// what should be default bahavior -
	290	delete [] pindex;
	291	delete fPVolId;
	292	delete fPTrack;
	293	fPVolId =0;
	294	fPTrack =0;
	295	return kFALSE;
98937d93	296	}
98937d93	297	}
8849da04	298
dfce6628	299	if (AliLog::GetDebugLevel("","AliTrackFitterRieman")>0 && gRandom->Rndm()<debugRatio){
8849da04	300	//
	301	// Debug Info
	302	//
	303	AliTrackPointArray *lPVolId = new AliTrackPointArray(npVolId);
	304	AliTrackPointArray *lPTrack = new AliTrackPointArray(npVolId);
dfce6628	305	AliTrackPointArray *lPTrackE = new AliTrackPointArray(npVolId);
8849da04	306	AliRieman * residual = fRieman->MakeResiduals();
8849da04	307	for (Int_t ipoint = 0; ipoint < npVolId; ipoint++){
dfce6628	308	AliTrackPoint p0, p0local;
	309	AliTrackPoint pFit, pFitlocal, pFitLocalE;
	310	fPVolId->GetPoint(p0,ipoint);
	311	Float_t lAngle = p0.GetAngle();
	312	p0local= p0.MasterToLocal();
	313	fPTrack->GetPoint(pFit,ipoint);
	314	pFitlocal= pFit.Rotate(lAngle);
	315	//
14b34be5	316	Float_t xyz[3], cov[6];
dfce6628	317	xyz[0] = pFitlocal.GetX();
	318	xyz[1] = pFitlocal.GetY();
	319	xyz[2] = pFitlocal.GetZ();
	320	for (Int_t icov=0; icov<6; icov++) cov[icov]=0;
	321	cov[3] = GetErrY2at(xyz[0]);
	322	cov[5] = GetErrZ2at(xyz[0]);
	323	pFitLocalE.SetXYZ(xyz,cov);
	324	//
	325	lPVolId->AddPoint(ipoint,&p0local);
	326	lPTrack->AddPoint(ipoint,&pFitlocal);
	327	lPTrackE->AddPoint(ipoint,&pFitLocalE);
8849da04	328	}
	329	//
	330	// debug info
	331	//
	332	Int_t nVol = volIds->GetSize();
	333	Int_t nVolFit = volIdsFit->GetSize();
	334	Int_t volId = volIds->At(0);
	335	Int_t modId =0;
25be1e5c	336	Int_t layer = AliGeomManager::VolUIDToLayer(volId,modId);
dfce6628	337	Int_t volIdFit = volIdsFit->At(0);
dfce6628	338	Int_t modIdFit =0;
25be1e5c	339	Int_t layerFit = AliGeomManager::VolUIDToLayer(volIdFit,modIdFit);
8849da04	340
	341	(*fDebugStream)<<"Fit"<<
	342	"VolId="<<volId<< // volume ID
	343	"Layer="<<layer<< // layer ID
	344	"Module="<<modId<< // module ID
dfce6628	345	"LayerFit="<<layerFit<< // layer ID fit
dfce6628	346	"ModuleFit="<<modIdFit<< // module ID fit
8849da04	347	"NVol="<<nVol<< // number of volumes
	348	"NvolFit="<<nVolFit<< // number of volumes to fit
	349	"Points0.="<<fPVolId<< // original points
	350	"Points1.="<<fPTrack<< // fitted points
	351	"LPoints0.="<<lPVolId<< // original points - local frame
	352	"LPoints1.="<<lPTrack<< // fitted points - local frame
dfce6628	353	"LPointsE.="<<lPTrackE<< // fitted points with ext error - local frame
8849da04	354	"Rieman.="<<this<< // original rieman fit
	355	"Res.="<<residual<< // residuals of rieman fit
	356	"\n";
	357	delete lPVolId;
	358	delete lPTrack;
	359	delete residual;
	360	}
98937d93	361
98937d93	362	delete [] pindex;
98937d93	363	return kTRUE;
	364	}
	365
8849da04	366
98937d93	367	void AliTrackFitterRieman::AddPoint(Float_t x, Float_t y, Float_t z, Float_t sy, Float_t sz)
	368	{
	369	//
8849da04	370	// add point to rieman fitter
98937d93	371	//
8849da04	372	fRieman->AddPoint(x,y,z,sy,sz);
8849da04	373	fNUsed = fRieman->GetN();
98937d93	374	}
98937d93	375
8849da04	376
8849da04	377
9c4c8863	378	Bool_t AliTrackFitterRieman::Update(){
98937d93	379	//
8849da04	380	//
98937d93	381	//
8849da04	382	fRieman->Update();
	383	fConv = kFALSE;
	384	if (fRieman->IsValid()){
	385	for (Int_t ipar=0; ipar<6; ipar++){
	386	fParams[ipar] = fRieman->GetParam()[ipar];
98937d93	387	}
8849da04	388	fChi2 = fRieman->GetChi2();
	389	fNdf = fRieman->GetN()- 2;
	390	fNUsed = fRieman->GetN();
	391	fConv = kTRUE;
98937d93	392	}
dfce6628	393	//
	394	//
	395	//
	396	TLinearFitter fitY(3,"pol2");
	397	TLinearFitter fitZ(3,"pol2");
	398	for (Int_t ip=0; ip<fRieman->GetN();ip++){
	399	Double_t x = fRieman->GetX()[ip];
	400	fitY.AddPoint(&x,fRieman->GetY()[ip]-fRieman->GetYat(x),1);
	401	fitZ.AddPoint(&x,fRieman->GetZ()[ip]-fRieman->GetZat(x),1);
	402	}
	403	fitY.Eval();
	404	fitZ.Eval();
	405	for (Int_t iparam=0; iparam<3; iparam++){
	406	fCorrY[iparam]=fitY.GetParameter(iparam);
	407	fCorrZ[iparam]=fitZ.GetParameter(iparam);
	408	}
	409	fCorrY[3]=fitY.GetChisquare()/Float_t(fRieman->GetN()-3);
	410	fCorrZ[3]=fitZ.GetChisquare()/Float_t(fRieman->GetN()-3);
9c4c8863	411
9c4c8863	412	return kTRUE;
98937d93	413	}
98937d93	414
dfce6628	415
dfce6628	416
6b6cba33	417	//_____________________________________________________________________________
98937d93	418	Bool_t AliTrackFitterRieman::GetPCA(const AliTrackPoint &p, AliTrackPoint &p2) const
98937d93	419	{
6b6cba33	420	//
98937d93	421	// Get the closest to a given spacepoint track trajectory point
98937d93	422	// Look for details in the description of the Fit() method
6b6cba33	423	//
98937d93	424	if (!fConv) return kFALSE;
	425
	426	// First X and Y coordinates
	427	Double_t sin = TMath::Sin(fAlpha);
	428	Double_t cos = TMath::Cos(fAlpha);
	429	// fParam[0] = 1/y0
	430	// fParam[1] = -x0/y0
	431	// fParam[2] = - (R^2 - x0^2 - y0^2)/y0
	432	if (fParams[0] == 0) return kFALSE;
cc345ce3	433	// Track parameters in the global coordinate system
98937d93	434	Double_t x0 = -fParams[1]/fParams[0]cos - 1./fParams[0]sin;
	435	Double_t y0 = 1./fParams[0]cos - fParams[1]/fParams[0]sin;
	436	if ((-fParams[2]fParams[0]+fParams[1]fParams[1]+1) <= 0) return kFALSE;
6b6cba33	437	Double_t r = TMath::Sqrt(-fParams[2]fParams[0]+fParams[1]fParams[1]+1)/
98937d93	438	fParams[0];
98937d93	439
cc345ce3	440	// Define space-point refence plane
	441	Double_t alphap = p.GetAngle();
	442	Double_t sinp = TMath::Sin(alphap);
	443	Double_t cosp = TMath::Cos(alphap);
	444	Double_t x = p.GetX()cosp + p.GetY()sinp;
	445	Double_t y = p.GetY()cosp - p.GetX()sinp;
	446	Double_t x0p= x0cosp + y0sinp;
	447	Double_t y0p= y0cosp - x0sinp;
6b6cba33	448	if ((rr - (x-x0p)(x-x0p))<0) {
6b6cba33	449	AliWarning(Form("Track extrapolation failed ! (Track radius = %f, track circle x = %f, space-point x = %f, reference plane angle = %f\n",r,x0p,x,alphap));
24d4520d	450	return kFALSE;
24d4520d	451	}
6b6cba33	452	Double_t temp = TMath::Sqrt(rr - (x-x0p)(x-x0p));
cc345ce3	453	Double_t y1 = y0p + temp;
	454	Double_t y2 = y0p - temp;
	455	Double_t yprime = y1;
	456	if(TMath::Abs(y2-y) < TMath::Abs(y1-y)) yprime = y2;
	457
	458	// Back to the global coordinate system
	459	Double_t xsecond = xcosp - yprimesinp;
	460	Double_t ysecond = yprimecosp + xsinp;
	461
	462	// Now Z coordinate and track angles
	463	Double_t x2 = xsecondcos + ysecondsin;
	464	Double_t zsecond = GetZat(x2);
	465	Double_t dydx = GetDYat(x2);
	466	Double_t dzdx = GetDZat(x2);
	467
	468	// Fill the cov matrix of the track extrapolation point
	469	Double_t cov[6] = {0,0,0,0,0,0};
	470	Double_t sigmax = 100*100.;
	471	cov[0] = sigmax; cov[1] = sigmaxdydx; cov[2] = sigmaxdzdx;
	472	cov[3] = sigmaxdydxdydx; cov[4] = sigmaxdydxdzdx;
	473	cov[5] = sigmaxdzdxdzdx;
	474
dfce6628	475	Double_t sigmay2 = GetErrY2at(x2);
	476	Double_t sigmaz2 = GetErrZ2at(x2);
	477	cov[3] += sigmay2;
	478	cov[5] += sigmaz2;
	479
	480
cc345ce3	481	Float_t newcov[6];
	482	newcov[0] = cov[0]coscos-
	483	2cov[1]sin*cos+
	484	cov[3]sinsin;
	485	newcov[1] = cov[1](coscos-sin*sin)-
	486	(cov[3]-cov[0])sincos;
	487	newcov[2] = cov[2]*cos-
	488	cov[4]*sin;
	489	newcov[3] = cov[0]sinsin+
	490	2cov[1]sin*cos+
	491	cov[3]coscos;
	492	newcov[4] = cov[4]*cos+
	493	cov[2]*sin;
	494	newcov[5] = cov[5];
	495
	496	p2.SetXYZ(xsecond,ysecond,zsecond,newcov);
dfce6628	497	Int_t debugLevel = AliLog::GetDebugLevel("","AliTrackFitterRieman");
	498	Float_t debugRatio = 1./(1.+debugLevel);
	499	if (AliLog::GetDebugLevel("","AliTrackFitterRieman")>0 && gRandom->Rndm()<debugRatio){
8849da04	500	AliTrackPoint lp0(p);
8849da04	501	AliTrackPoint lp2(p2);
d9e9045c	502	AliTrackPoint localp0(p);
	503	AliTrackPoint localp2(p2);
	504	Float_t lAngle = lp0.GetAngle();
	505	localp0 = localp0.Rotate(lAngle);
	506	localp2 = localp2.Rotate(lAngle);
	507
dfce6628	508	(*fDebugStream)<<"PCA"<<
d9e9045c	509	"P0.="<<&lp0<< //global position
8849da04	510	"P2.="<<&lp2<<
d9e9045c	511	"LP0.="<<&localp0<< //local position
d9e9045c	512	"LP2.="<<&localp2<<
8849da04	513	"\n";
8849da04	514	}
98937d93	515	return kTRUE;
98937d93	516	}
dfce6628	517
	518	Double_t AliTrackFitterRieman::GetYat(Double_t x) const {
	519	//
	520	// get y position at given point
	521	//
	522	Double_t correction=0;
	523	if (fBCorrection){ // systematic effect correction
	524	correction = fCorrY[0]+fCorrY[1]x +fCorrY[2]x*x;
	525	}
	526	return fRieman->GetYat(x)+correction;
	527	}
	528
	529	Double_t AliTrackFitterRieman::GetZat(Double_t x) const {
	530	//
	531	// get z position at given point
	532	//
	533	Double_t correction=0;
	534	if (fBCorrection){ // systematic effect correction
	535	correction = fCorrZ[0]+fCorrZ[1]x +fCorrZ[2]x*x;
	536	}
	537	return fRieman->GetZat(x)+correction;
	538	}
	539
	540	Double_t AliTrackFitterRieman::GetErrY2at(Double_t x) const {
	541	//
	542	// get estimate of extrapolation error
	543	//
	544	Double_t error = fRieman->GetErrY(x);
	545	Double_t correction=0;
	546	if (fBCorrection){ // everestimate error due systematic effect
	547	error *=fCorrY[3];
	548	correction = fCorrY[0]+fCorrY[1]x +fCorrY[2]x*x;
	549	correction *=correction;
	550	}
	551	return TMath::Sqrt(error+correction);
	552	}
	553
	554	Double_t AliTrackFitterRieman::GetErrZ2at(Double_t x) const {
	555	//
	556	// get estimate of extrapolation error
	557	//
	558	Double_t error = fRieman->GetErrZ(x)*fCorrZ[3];
	559	Double_t correction=0;
	560	if (fBCorrection){
	561	error *= fCorrZ[3];
	562	correction = fCorrZ[0]+fCorrZ[1]x +fCorrZ[2]x*x;
	563	correction*= correction;
	564	}
	565	return TMath::Sqrt(error+correction);
	566	}
d4af2e1d	567
	568	void AliTrackFitterRieman::SetParam(Int_t i, Double_t par) {
	569	if (i<0 \|\| i>5) return;
	570	fParams[i]=par;
	571	fRieman->GetParam()[i]=par;
	572	}