// are implemented.
// Origin: I.Belikov, CERN, Jouri.Belikov@cern.ch //
///////////////////////////////////////////////////////////////////////////////
+#include <TMatrixDSym.h>
#include "AliExternalTrackParam.h"
#include "AliESDVertex.h"
+#include "TPolyMarker3D.h"
#include "AliLog.h"
ClassImp(AliExternalTrackParam)
+Double32_t AliExternalTrackParam::fgMostProbablePt=kMostProbablePt;
+
//_____________________________________________________________________________
AliExternalTrackParam::AliExternalTrackParam() :
- TObject(),
+ AliVParticle(),
fX(0),
fAlpha(0)
{
//_____________________________________________________________________________
AliExternalTrackParam::AliExternalTrackParam(const AliExternalTrackParam &track):
- TObject(track),
+ AliVParticle(track),
fX(track.fX),
fAlpha(track.fAlpha)
{
for (Int_t i = 0; i < 15; i++) fC[i] = track.fC[i];
}
+//_____________________________________________________________________________
+AliExternalTrackParam& AliExternalTrackParam::operator=(const AliExternalTrackParam &trkPar)
+{
+ //
+ // assignment operator
+ //
+
+ if (this!=&trkPar) {
+ AliVParticle::operator=(trkPar);
+ fX = trkPar.fX;
+ fAlpha = trkPar.fAlpha;
+
+ for (Int_t i = 0; i < 5; i++) fP[i] = trkPar.fP[i];
+ for (Int_t i = 0; i < 15; i++) fC[i] = trkPar.fC[i];
+ }
+
+ return *this;
+}
+
//_____________________________________________________________________________
AliExternalTrackParam::AliExternalTrackParam(Double_t x, Double_t alpha,
const Double_t param[5],
const Double_t covar[15]) :
- TObject(),
+ AliVParticle(),
fX(x),
fAlpha(alpha)
{
for (Int_t i = 0; i < 15; i++) fC[i] = 0;
}
+//_____________________________________________________________________________
+void AliExternalTrackParam::AddCovariance(const Double_t c[15]) {
+ //
+ // Add "something" to the track covarince matrix.
+ // May be needed to account for unknown mis-calibration/mis-alignment
+ //
+ fC[0] +=c[0];
+ fC[1] +=c[1]; fC[2] +=c[2];
+ fC[3] +=c[3]; fC[4] +=c[4]; fC[5] +=c[5];
+ fC[6] +=c[6]; fC[7] +=c[7]; fC[8] +=c[8]; fC[9] +=c[9];
+ fC[10]+=c[10]; fC[11]+=c[11]; fC[12]+=c[12]; fC[13]+=c[13]; fC[14]+=c[14];
+}
+
+
Double_t AliExternalTrackParam::GetP() const {
//---------------------------------------------------------------------
// This function returns the track momentum
return -d;
}
-Bool_t AliExternalTrackParam::
-CorrectForMaterial(Double_t d, Double_t x0, Double_t mass) {
+Bool_t AliExternalTrackParam::CorrectForMeanMaterial
+(Double_t xOverX0, Double_t xTimesRho, Double_t mass, Bool_t anglecorr,
+ Double_t (*Bethe)(Double_t)) {
+ //------------------------------------------------------------------
+ // This function corrects the track parameters for the crossed material.
+ // "xOverX0" - X/X0, the thickness in units of the radiation length.
+ // "xTimesRho" - is the product length*density (g/cm^2).
+ // "mass" - the mass of this particle (GeV/c^2).
+ //------------------------------------------------------------------
+ Double_t &fP2=fP[2];
+ Double_t &fP3=fP[3];
+ Double_t &fP4=fP[4];
+
+ Double_t &fC22=fC[5];
+ Double_t &fC33=fC[9];
+ Double_t &fC43=fC[13];
+ Double_t &fC44=fC[14];
+
+ //Apply angle correction, if requested
+ if(anglecorr) {
+ Double_t angle=TMath::Sqrt((1.+ fP3*fP3)/(1.- fP2*fP2));
+ xOverX0 *=angle;
+ xTimesRho *=angle;
+ }
+
+ Double_t p=GetP();
+ Double_t p2=p*p;
+ Double_t beta2=p2/(p2 + mass*mass);
+
+ //Multiple scattering******************
+ if (xOverX0 != 0) {
+ Double_t theta2=14.1*14.1/(beta2*p2*1e6)*TMath::Abs(xOverX0);
+ if(theta2>TMath::Pi()*TMath::Pi()) return kFALSE;
+ //Double_t theta2=1.0259e-6*14*14/28/(beta2*p2)*TMath::Abs(d)*9.36*2.33;
+ fC22 += theta2*(1.- fP2*fP2)*(1. + fP3*fP3);
+ fC33 += theta2*(1. + fP3*fP3)*(1. + fP3*fP3);
+ fC43 += theta2*fP3*fP4*(1. + fP3*fP3);
+ fC44 += theta2*fP3*fP4*fP3*fP4;
+ }
+
+ //Energy losses************************
+ if ((xTimesRho != 0.) && (beta2 < 1.)) {
+ Double_t dE=Bethe(beta2)*xTimesRho;
+ Double_t e=TMath::Sqrt(p2 + mass*mass);
+ if ( TMath::Abs(dE) > 0.3*e ) return kFALSE; //30% energy loss is too much!
+ fP4*=(1.- e/p2*dE);
+ if (TMath::Abs(fP4)>100.) return kFALSE; // Do not track below 10 MeV/c
+
+
+ // Approximate energy loss fluctuation (M.Ivanov)
+ const Double_t knst=0.07; // To be tuned.
+ Double_t sigmadE=knst*TMath::Sqrt(TMath::Abs(dE));
+ fC44+=((sigmadE*e/p2*fP4)*(sigmadE*e/p2*fP4));
+
+ }
+
+ return kTRUE;
+}
+
+
+Bool_t AliExternalTrackParam::CorrectForMaterial
+(Double_t d, Double_t x0, Double_t mass, Double_t (*Bethe)(Double_t)) {
//------------------------------------------------------------------
+ // Deprecated function !
+ // Better use CorrectForMeanMaterial instead of it.
+ //
// This function corrects the track parameters for the crossed material
// "d" - the thickness (fraction of the radiation length)
// "x0" - the radiation length (g/cm^2)
//Multiple scattering******************
if (d!=0) {
Double_t theta2=14.1*14.1/(beta2*p2*1e6)*TMath::Abs(d);
+ if(theta2>TMath::Pi()*TMath::Pi()) return kFALSE;
//Double_t theta2=1.0259e-6*14*14/28/(beta2*p2)*TMath::Abs(d)*9.36*2.33;
fC22 += theta2*(1.- fP2*fP2)*(1. + fP3*fP3);
fC33 += theta2*(1. + fP3*fP3)*(1. + fP3*fP3);
//Energy losses************************
if (x0!=0. && beta2<1) {
d*=x0;
- Double_t dE=0.153e-3/beta2*(log(5940*beta2/(1-beta2)) - beta2)*d;
- if (beta2/(1-beta2)>3.5*3.5)
- dE=0.153e-3/beta2*(log(3.5*5940)+0.5*log(beta2/(1-beta2)) - beta2)*d;
-
- fP4*=(1.- TMath::Sqrt(p2 + mass*mass)/p2*dE);
+ Double_t dE=Bethe(beta2)*d;
+ Double_t e=TMath::Sqrt(p2 + mass*mass);
+ if ( TMath::Abs(dE) > 0.3*e ) return kFALSE; //30% energy loss is too much!
+ fP4*=(1.- e/p2*dE);
+
+ // Approximate energy loss fluctuation (M.Ivanov)
+ const Double_t knst=0.07; // To be tuned.
+ Double_t sigmadE=knst*TMath::Sqrt(TMath::Abs(dE));
+ fC44+=((sigmadE*e/p2*fP4)*(sigmadE*e/p2*fP4));
+
}
return kTRUE;
}
+Double_t ApproximateBetheBloch(Double_t beta2) {
+ //------------------------------------------------------------------
+ // This is an approximation of the Bethe-Bloch formula with
+ // the density effect taken into account at beta*gamma > 3.5
+ // (the approximation is reasonable only for solid materials)
+ //------------------------------------------------------------------
+ if (beta2 >= 1) return kVeryBig;
+
+ if (beta2/(1-beta2)>3.5*3.5)
+ return 0.153e-3/beta2*(log(3.5*5940)+0.5*log(beta2/(1-beta2)) - beta2);
+
+ return 0.153e-3/beta2*(log(5940*beta2/(1-beta2)) - beta2);
+}
+
Bool_t AliExternalTrackParam::Rotate(Double_t alpha) {
//------------------------------------------------------------------
// Transform this track to the local coord. system rotated
//+++++++++++++++++++++++++++++++++++++++++
GetXYZ(x);
- if (TMath::Abs(Get1Pt()) < kAlmost0){ //straight-line tracks
+ if (OneOverPt() < kAlmost0 || TMath::Abs(bz) < kAlmost0Field ){ //straight-line tracks
Double_t unit[3]; GetDirection(unit);
x[0]+=unit[0]*len;
x[1]+=unit[1]*len;
return (d*szz*d - 2*d*sdz*z + z*sdd*z)/det;
}
+Double_t AliExternalTrackParam::
+GetPredictedChi2(Double_t p[3],Double_t covyz[3],Double_t covxyz[3]) const {
+ //----------------------------------------------------------------
+ // Estimate the chi2 of the 3D space point "p" and
+ // the full covariance matrix "covyz" and "covxyz"
+ //
+ // Cov(x,x) ... : covxyz[0]
+ // Cov(y,x) ... : covxyz[1] covyz[0]
+ // Cov(z,x) ... : covxyz[2] covyz[1] covyz[2]
+ //----------------------------------------------------------------
+
+ Double_t res[3] = {
+ GetX() - p[0],
+ GetY() - p[1],
+ GetZ() - p[2]
+ };
+
+ Double_t f=GetSnp();
+ if (TMath::Abs(f) >= kAlmost1) return kVeryBig;
+ Double_t r=TMath::Sqrt(1.- f*f);
+ Double_t a=f/r, b=GetTgl()/r;
+
+ Double_t s2=333.*333.; //something reasonably big (cm^2)
+
+ TMatrixDSym v(3);
+ v(0,0)= s2; v(0,1)= a*s2; v(0,2)= b*s2;;
+ v(1,0)=a*s2; v(1,1)=a*a*s2 + GetSigmaY2(); v(1,2)=a*b*s2 + GetSigmaZY();
+ v(2,0)=b*s2; v(2,1)=a*b*s2 + GetSigmaZY(); v(2,2)=b*b*s2 + GetSigmaZ2();
+
+ v(0,0)+=covxyz[0]; v(0,1)+=covxyz[1]; v(0,2)+=covxyz[2];
+ v(1,0)+=covxyz[1]; v(1,1)+=covyz[0]; v(1,2)+=covyz[1];
+ v(2,0)+=covxyz[2]; v(2,1)+=covyz[1]; v(2,2)+=covyz[2];
+
+ v.Invert();
+ if (!v.IsValid()) return kVeryBig;
+
+ Double_t chi2=0.;
+ for (Int_t i = 0; i < 3; i++)
+ for (Int_t j = 0; j < 3; j++) chi2 += res[i]*res[j]*v(i,j);
+
+ return chi2;
+
+
+}
+
+Bool_t AliExternalTrackParam::
+PropagateTo(Double_t p[3],Double_t covyz[3],Double_t covxyz[3],Double_t bz) {
+ //----------------------------------------------------------------
+ // Propagate this track to the plane
+ // the 3D space point "p" (with the covariance matrix "covyz" and "covxyz")
+ // belongs to.
+ // The magnetic field is "bz" (kG)
+ //
+ // The track curvature and the change of the covariance matrix
+ // of the track parameters are negleted !
+ // (So the "step" should be small compared with 1/curvature)
+ //----------------------------------------------------------------
+
+ Double_t f=GetSnp();
+ if (TMath::Abs(f) >= kAlmost1) return kFALSE;
+ Double_t r=TMath::Sqrt(1.- f*f);
+ Double_t a=f/r, b=GetTgl()/r;
+
+ Double_t s2=333.*333.; //something reasonably big (cm^2)
+
+ TMatrixDSym tV(3);
+ tV(0,0)= s2; tV(0,1)= a*s2; tV(0,2)= b*s2;
+ tV(1,0)=a*s2; tV(1,1)=a*a*s2; tV(1,2)=a*b*s2;
+ tV(2,0)=b*s2; tV(2,1)=a*b*s2; tV(2,2)=b*b*s2;
+
+ TMatrixDSym pV(3);
+ pV(0,0)=covxyz[0]; pV(0,1)=covxyz[1]; pV(0,2)=covxyz[2];
+ pV(1,0)=covxyz[1]; pV(1,1)=covyz[0]; pV(1,2)=covyz[1];
+ pV(2,0)=covxyz[2]; pV(2,1)=covyz[1]; pV(2,2)=covyz[2];
+
+ TMatrixDSym tpV(tV);
+ tpV+=pV;
+ tpV.Invert();
+ if (!tpV.IsValid()) return kFALSE;
+
+ TMatrixDSym pW(3),tW(3);
+ for (Int_t i=0; i<3; i++)
+ for (Int_t j=0; j<3; j++) {
+ pW(i,j)=tW(i,j)=0.;
+ for (Int_t k=0; k<3; k++) {
+ pW(i,j) += tV(i,k)*tpV(k,j);
+ tW(i,j) += pV(i,k)*tpV(k,j);
+ }
+ }
+
+ Double_t t[3] = {GetX(), GetY(), GetZ()};
+
+ Double_t x=0.;
+ for (Int_t i=0; i<3; i++) x += (tW(0,i)*t[i] + pW(0,i)*p[i]);
+ Double_t crv=GetC(bz);
+ if (TMath::Abs(b) < kAlmost0Field) crv=0.;
+ f += crv*(x-fX);
+ if (TMath::Abs(f) >= kAlmost1) return kFALSE;
+ fX=x;
+
+ fP[0]=0.;
+ for (Int_t i=0; i<3; i++) fP[0] += (tW(1,i)*t[i] + pW(1,i)*p[i]);
+ fP[1]=0.;
+ for (Int_t i=0; i<3; i++) fP[1] += (tW(2,i)*t[i] + pW(2,i)*p[i]);
+
+ return kTRUE;
+}
+
+Double_t *AliExternalTrackParam::GetResiduals(
+Double_t *p,Double_t *cov,Bool_t updated) const {
+ //------------------------------------------------------------------
+ // Returns the track residuals with the space point "p" having
+ // the covariance matrix "cov".
+ // If "updated" is kTRUE, the track parameters expected to be updated,
+ // otherwise they must be predicted.
+ //------------------------------------------------------------------
+ static Double_t res[2];
+
+ Double_t r00=cov[0], r01=cov[1], r11=cov[2];
+ if (updated) {
+ r00-=fC[0]; r01-=fC[1]; r11-=fC[2];
+ } else {
+ r00+=fC[0]; r01+=fC[1]; r11+=fC[2];
+ }
+ Double_t det=r00*r11 - r01*r01;
+
+ if (TMath::Abs(det) < kAlmost0) return 0;
+
+ Double_t tmp=r00; r00=r11/det; r11=tmp/det;
+
+ if (r00 < 0.) return 0;
+ if (r11 < 0.) return 0;
+
+ Double_t dy = fP[0] - p[0];
+ Double_t dz = fP[1] - p[1];
+
+ res[0]=dy*TMath::Sqrt(r00);
+ res[1]=dz*TMath::Sqrt(r11);
+
+ return res;
+}
+
Bool_t AliExternalTrackParam::Update(Double_t p[2], Double_t cov[3]) {
//------------------------------------------------------------------
// Update the track parameters with the space point "p" having
if (TMath::Abs(dt1)/(TMath::Abs(t1)+1.e-3) < 1.e-4)
if (TMath::Abs(dt2)/(TMath::Abs(t2)+1.e-3) < 1.e-4) {
if ((gt1*gt1+gt2*gt2) > 1.e-4/dy2/dy2)
- AliWarning(" stopped at not a stationary point !");
+ AliDebug(1," stopped at not a stationary point !");
Double_t lmb=h11+h22; lmb=lmb-TMath::Sqrt(lmb*lmb-4*det);
if (lmb < 0.)
- AliWarning(" stopped at not a minimum !");
+ AliDebug(1," stopped at not a minimum !");
break;
}
if (dd<dm) break;
dt1*=0.5; dt2*=0.5;
if (div>512) {
- AliWarning(" overshoot !"); break;
+ AliDebug(1," overshoot !"); break;
}
}
dm=dd;
}
- if (max<=0) AliWarning(" too many iterations !");
+ if (max<=0) AliDebug(1," too many iterations !");
Double_t cs=TMath::Cos(GetAlpha());
Double_t sn=TMath::Sin(GetAlpha());
}
-
-
-Bool_t AliExternalTrackParam::PropagateToDCA(const AliESDVertex *vtx, Double_t b, Double_t maxd){
+Bool_t AliExternalTrackParam::PropagateToDCA(const AliESDVertex *vtx,
+Double_t b, Double_t maxd, Double_t dz[2], Double_t covar[3]) {
//
- // Try to relate this track to the vertex "vtx",
+ // Propagate this track to the DCA to vertex "vtx",
// if the (rough) transverse impact parameter is not bigger then "maxd".
// Magnetic field is "b" (kG).
//
Double_t sn=TMath::Sin(alpha), cs=TMath::Cos(alpha);
Double_t x=GetX(), y=GetParameter()[0], snp=GetParameter()[2];
Double_t xv= vtx->GetXv()*cs + vtx->GetYv()*sn;
- Double_t yv=-vtx->GetXv()*sn + vtx->GetYv()*cs;
+ Double_t yv=-vtx->GetXv()*sn + vtx->GetYv()*cs, zv=vtx->GetZv();
x-=xv; y-=yv;
//Estimate the impact parameter neglecting the track curvature
if (d > maxd) return kFALSE;
//Propagate to the DCA
- Double_t crv=0.299792458e-3*b*GetParameter()[4];
+ Double_t crv=kB2C*b*GetParameter()[4];
+ if (TMath::Abs(b) < kAlmost0Field) crv=0.;
+
Double_t tgfv=-(crv*x - snp)/(crv*y + TMath::Sqrt(1.-snp*snp));
sn=tgfv/TMath::Sqrt(1.+ tgfv*tgfv); cs=TMath::Sqrt(1.- sn*sn);
+ if (TMath::Abs(tgfv)>0.) cs = sn/tgfv;
+ else cs=1.;
x = xv*cs + yv*sn;
yv=-xv*sn + yv*cs; xv=x;
if (!Propagate(alpha+TMath::ASin(sn),xv,b)) return kFALSE;
- return kTRUE;
-}
-
+ if (dz==0) return kTRUE;
+ dz[0] = GetParameter()[0] - yv;
+ dz[1] = GetParameter()[1] - zv;
+
+ if (covar==0) return kTRUE;
+ Double_t cov[6]; vtx->GetCovMatrix(cov);
-
-Bool_t Local2GlobalMomentum(Double_t p[3],Double_t alpha) {
- //----------------------------------------------------------------
- // This function performs local->global transformation of the
- // track momentum.
- // When called, the arguments are:
- // p[0] = 1/pt of the track;
- // p[1] = sine of local azim. angle of the track momentum;
- // p[2] = tangent of the track momentum dip angle;
- // alpha - rotation angle.
- // The result is returned as:
- // p[0] = px
- // p[1] = py
- // p[2] = pz
- // Results for (nearly) straight tracks are meaningless !
- //----------------------------------------------------------------
- if (TMath::Abs(p[0])<=kAlmost0) return kFALSE;
- if (TMath::Abs(p[1])> kAlmost1) return kFALSE;
-
- Double_t pt=1./TMath::Abs(p[0]);
- Double_t cs=TMath::Cos(alpha), sn=TMath::Sin(alpha);
- Double_t r=TMath::Sqrt(1 - p[1]*p[1]);
- p[0]=pt*(r*cs - p[1]*sn); p[1]=pt*(p[1]*cs + r*sn); p[2]=pt*p[2];
+ //***** Improvements by A.Dainese
+ alpha=GetAlpha(); sn=TMath::Sin(alpha); cs=TMath::Cos(alpha);
+ Double_t s2ylocvtx = cov[0]*sn*sn + cov[2]*cs*cs - 2.*cov[1]*cs*sn;
+ covar[0] = GetCovariance()[0] + s2ylocvtx; // neglecting correlations
+ covar[1] = GetCovariance()[1]; // between (x,y) and z
+ covar[2] = GetCovariance()[2] + cov[5]; // in vertex's covariance matrix
+ //*****
return kTRUE;
}
-Bool_t Local2GlobalPosition(Double_t r[3],Double_t alpha) {
- //----------------------------------------------------------------
- // This function performs local->global transformation of the
- // track position.
- // When called, the arguments are:
- // r[0] = local x
- // r[1] = local y
- // r[2] = local z
- // alpha - rotation angle.
- // The result is returned as:
- // r[0] = global x
- // r[1] = global y
- // r[2] = global z
- //----------------------------------------------------------------
- Double_t cs=TMath::Cos(alpha), sn=TMath::Sin(alpha), x=r[0];
- r[0]=x*cs - r[1]*sn; r[1]=x*sn + r[1]*cs;
-
- return kTRUE;
-}
void AliExternalTrackParam::GetDirection(Double_t d[3]) const {
//----------------------------------------------------------------
//----------------------------------------------------------------
Double_t cs=TMath::Cos(fAlpha), sn=TMath::Sin(fAlpha);
Double_t snp=fP[2];
- Double_t csp =TMath::Sqrt(1.- snp*snp);
+ Double_t csp =TMath::Sqrt((1.- snp)*(1.+snp));
Double_t norm=TMath::Sqrt(1.+ fP[3]*fP[3]);
d[0]=(csp*cs - snp*sn)/norm;
d[1]=(snp*cs + csp*sn)/norm;
d[2]=fP[3]/norm;
}
-Bool_t AliExternalTrackParam::GetPxPyPz(Double_t *p) const {
+Bool_t AliExternalTrackParam::GetPxPyPz(Double_t p[3]) const {
//---------------------------------------------------------------------
// This function returns the global track momentum components
// Results for (nearly) straight tracks are meaningless !
return Local2GlobalMomentum(p,fAlpha);
}
+Double_t AliExternalTrackParam::Px() const {
+ //---------------------------------------------------------------------
+ // Returns x-component of momentum
+ // Result for (nearly) straight tracks is meaningless !
+ //---------------------------------------------------------------------
+
+ Double_t p[3]={kVeryBig,kVeryBig,kVeryBig};
+ GetPxPyPz(p);
+
+ return p[0];
+}
+
+Double_t AliExternalTrackParam::Py() const {
+ //---------------------------------------------------------------------
+ // Returns y-component of momentum
+ // Result for (nearly) straight tracks is meaningless !
+ //---------------------------------------------------------------------
+
+ Double_t p[3]={kVeryBig,kVeryBig,kVeryBig};
+ GetPxPyPz(p);
+
+ return p[1];
+}
+
+Double_t AliExternalTrackParam::Pz() const {
+ //---------------------------------------------------------------------
+ // Returns z-component of momentum
+ // Result for (nearly) straight tracks is meaningless !
+ //---------------------------------------------------------------------
+
+ Double_t p[3]={kVeryBig,kVeryBig,kVeryBig};
+ GetPxPyPz(p);
+
+ return p[2];
+}
+
+Double_t AliExternalTrackParam::Xv() const {
+ //---------------------------------------------------------------------
+ // Returns x-component of first track point
+ //---------------------------------------------------------------------
+
+ Double_t r[3]={0.,0.,0.};
+ GetXYZ(r);
+
+ return r[0];
+}
+
+Double_t AliExternalTrackParam::Yv() const {
+ //---------------------------------------------------------------------
+ // Returns y-component of first track point
+ //---------------------------------------------------------------------
+
+ Double_t r[3]={0.,0.,0.};
+ GetXYZ(r);
+
+ return r[1];
+}
+
+Double_t AliExternalTrackParam::Zv() const {
+ //---------------------------------------------------------------------
+ // Returns z-component of first track point
+ //---------------------------------------------------------------------
+
+ Double_t r[3]={0.,0.,0.};
+ GetXYZ(r);
+
+ return r[2];
+}
+
+Double_t AliExternalTrackParam::Theta() const {
+ // return theta angle of momentum
+
+ return 0.5*TMath::Pi() - TMath::ATan(fP[3]);
+}
+
+Double_t AliExternalTrackParam::Phi() const {
+ //---------------------------------------------------------------------
+ // Returns the azimuthal angle of momentum
+ // 0 <= phi < 2*pi
+ //---------------------------------------------------------------------
+
+ Double_t phi=TMath::ASin(fP[2]) + fAlpha;
+ if (phi<0.) phi+=2.*TMath::Pi();
+ else if (phi>=2.*TMath::Pi()) phi-=2.*TMath::Pi();
+
+ return phi;
+}
+
+Double_t AliExternalTrackParam::M() const {
+ // return particle mass
+
+ // No mass information available so far.
+ // Redifine in derived class!
+
+ return -999.;
+}
+
+Double_t AliExternalTrackParam::E() const {
+ // return particle energy
+
+ // No PID information available so far.
+ // Redifine in derived class!
+
+ return -999.;
+}
+
+Double_t AliExternalTrackParam::Eta() const {
+ // return pseudorapidity
+
+ return -TMath::Log(TMath::Tan(0.5 * Theta()));
+}
+
+Double_t AliExternalTrackParam::Y() const {
+ // return rapidity
+
+ // No PID information available so far.
+ // Redifine in derived class!
+
+ return -999.;
+}
+
Bool_t AliExternalTrackParam::GetXYZ(Double_t *r) const {
//---------------------------------------------------------------------
// This function returns the global track position
}
Double_t pt=1./TMath::Abs(fP[4]);
Double_t cs=TMath::Cos(fAlpha), sn=TMath::Sin(fAlpha);
- Double_t r=TMath::Sqrt(1-fP[2]*fP[2]);
+ Double_t r=TMath::Sqrt((1.-fP[2])*(1.+fP[2]));
Double_t m00=-sn, m10=cs;
Double_t m23=-pt*(sn + fP[2]*cs/r), m43=-pt*pt*(r*cs - fP[2]*sn);
Double_t m24= pt*(cs - fP[2]*sn/r), m44=-pt*pt*(r*sn + fP[2]*cs);
Double_t m35=pt, m45=-pt*pt*fP[3];
+ m43*=GetSign();
+ m44*=GetSign();
+ m45*=GetSign();
+
cv[0 ] = fC[0]*m00*m00;
cv[1 ] = fC[0]*m00*m10;
cv[2 ] = fC[0]*m10*m10;
Double_t res = fP[2]+dx*crv;
return res;
}
+
+Bool_t AliExternalTrackParam::GetDistance(AliExternalTrackParam *param2, Double_t x, Double_t dist[3], Double_t bz){
+ //------------------------------------------------------------------------
+ // Get the distance between two tracks at the local position x
+ // working in the local frame of this track.
+ // Origin : Marian.Ivanov@cern.ch
+ //-----------------------------------------------------------------------
+ Double_t xyz[3];
+ Double_t xyz2[3];
+ xyz[0]=x;
+ if (!GetYAt(x,bz,xyz[1])) return kFALSE;
+ if (!GetZAt(x,bz,xyz[2])) return kFALSE;
+ //
+ //
+ if (TMath::Abs(GetAlpha()-param2->GetAlpha())<kAlmost0){
+ xyz2[0]=x;
+ if (!param2->GetYAt(x,bz,xyz2[1])) return kFALSE;
+ if (!param2->GetZAt(x,bz,xyz2[2])) return kFALSE;
+ }else{
+ //
+ Double_t xyz1[3];
+ Double_t dfi = param2->GetAlpha()-GetAlpha();
+ Double_t ca = TMath::Cos(dfi), sa = TMath::Sin(dfi);
+ xyz2[0] = xyz[0]*ca+xyz[1]*sa;
+ xyz2[1] = -xyz[0]*sa+xyz[1]*ca;
+ //
+ xyz1[0]=xyz2[0];
+ if (!param2->GetYAt(xyz2[0],bz,xyz1[1])) return kFALSE;
+ if (!param2->GetZAt(xyz2[0],bz,xyz1[2])) return kFALSE;
+ //
+ xyz2[0] = xyz1[0]*ca-xyz1[1]*sa;
+ xyz2[1] = +xyz1[0]*sa+xyz1[1]*ca;
+ xyz2[2] = xyz1[2];
+ }
+ dist[0] = xyz[0]-xyz2[0];
+ dist[1] = xyz[1]-xyz2[1];
+ dist[2] = xyz[2]-xyz2[2];
+
+ return kTRUE;
+}
+
+
+//
+// Draw functionality.
+// Origin: Marian Ivanov, Marian.Ivanov@cern.ch
+//
+
+void AliExternalTrackParam::DrawTrack(Float_t magf, Float_t minR, Float_t maxR, Float_t stepR){
+ //
+ // Draw track line
+ //
+ if (minR>maxR) return ;
+ if (stepR<=0) return ;
+ Int_t npoints = TMath::Nint((maxR-minR)/stepR)+1;
+ if (npoints<1) return;
+ TPolyMarker3D *polymarker = new TPolyMarker3D(npoints);
+ FillPolymarker(polymarker, magf,minR,maxR,stepR);
+ polymarker->Draw();
+}
+
+//
+void AliExternalTrackParam::FillPolymarker(TPolyMarker3D *pol, Float_t magF, Float_t minR, Float_t maxR, Float_t stepR){
+ //
+ // Fill points in the polymarker
+ //
+ Int_t counter=0;
+ for (Double_t r=minR; r<maxR; r+=stepR){
+ Double_t point[3];
+ GetXYZAt(r,magF,point);
+ pol->SetPoint(counter,point[0],point[1], point[2]);
+ printf("xyz\t%f\t%f\t%f\n",point[0], point[1],point[2]);
+ counter++;
+ }
+}
git://git.uio.no / u / mrichter / AliRoot.git / blobdiff