Additional protection for the case when galice.root does not exist
[u/mrichter/AliRoot.git] / ITS / AliITStrackV2.cxx
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006b5f7f 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
66e811e2 16///////////////////////////////////////////////////////////////////////////
006b5f7f 17// Implementation of the ITS track class
18//
19// Origin: Iouri Belikov, CERN, Jouri.Belikov@cern.ch
a9a2d814 20// dEdx analysis by: Boris Batyunya, JINR, Boris.Batiounia@cern.ch
66e811e2 21///////////////////////////////////////////////////////////////////////////
006b5f7f 22#include <TMath.h>
006b5f7f 23
24#include "AliCluster.h"
6c94f330 25#include "AliTracker.h"
83d73500 26#include "AliESDtrack.h"
006b5f7f 27#include "AliITStrackV2.h"
28
8602c008 29const Int_t AliITStrackV2::fgkWARN = 5;
30
1aedd96e 31ClassImp(AliITStrackV2)
8676d691 32
e43c066c 33
006b5f7f 34//____________________________________________________________________________
6c94f330 35AliITStrackV2::AliITStrackV2() : AliKalmanTrack(),
22b13da0 36 fdEdx(0),
83d73500 37 fESDtrack(0)
e43c066c 38{
ef7253ac 39 for(Int_t i=0; i<2*kMaxLayer; i++) fIndex[i]=-1;
e43c066c 40 for(Int_t i=0; i<4; i++) fdEdxSample[i]=0;
e43c066c 41}
42
83d73500 43
22b13da0 44//____________________________________________________________________________
67c3dcbe 45AliITStrackV2::AliITStrackV2(AliESDtrack& t,Bool_t c) throw (const Char_t *) :
6c94f330 46 AliKalmanTrack(),
47 fdEdx(t.GetITSsignal()),
48 fESDtrack(&t)
49{
83d73500 50 //------------------------------------------------------------------
67c3dcbe 51 // Conversion ESD track -> ITS track.
52 // If c==kTRUE, create the ITS track out of the constrained params.
83d73500 53 //------------------------------------------------------------------
6c94f330 54 const AliExternalTrackParam *par=&t;
55 if (c) {
6c4ef2ed 56 par=t.GetConstrainedParam();
6c94f330 57 if (!par) throw "AliITStrackV2: conversion failed !\n";
58 }
59 Set(par->GetX(),par->GetAlpha(),par->GetParameter(),par->GetCovariance());
60
61 //if (!Invariant()) throw "AliITStrackV2: conversion failed !\n";
62
83d73500 63 SetLabel(t.GetLabel());
64 SetMass(t.GetMass());
6c94f330 65 SetNumberOfClusters(t.GetITSclusters(fIndex));
006b5f7f 66
83d73500 67 if (t.GetStatus()&AliESDtrack::kTIME) {
68 StartTimeIntegral();
69 Double_t times[10]; t.GetIntegratedTimes(times); SetIntegratedTimes(times);
70 SetIntegratedLength(t.GetIntegratedLength());
71 }
e43c066c 72
68b8060b 73 for(Int_t i=0; i<4; i++) fdEdxSample[i]=0;
006b5f7f 74}
75
15dd636f 76void AliITStrackV2::UpdateESDtrack(ULong_t flags) const {
83d73500 77 fESDtrack->UpdateTrackParams(this,flags);
78}
79
006b5f7f 80//____________________________________________________________________________
6c94f330 81AliITStrackV2::AliITStrackV2(const AliITStrackV2& t) :
82 AliKalmanTrack(t),
83 fdEdx(t.fdEdx),
84 fESDtrack(t.fESDtrack)
85{
006b5f7f 86 //------------------------------------------------------------------
87 //Copy constructor
88 //------------------------------------------------------------------
ef7253ac 89 Int_t i;
ef7253ac 90 for (i=0; i<4; i++) fdEdxSample[i]=t.fdEdxSample[i];
6c94f330 91 for (i=0; i<2*kMaxLayer; i++) fIndex[i]=t.fIndex[i];
006b5f7f 92}
a9a2d814 93
006b5f7f 94//_____________________________________________________________________________
95Int_t AliITStrackV2::Compare(const TObject *o) const {
96 //-----------------------------------------------------------------
97 // This function compares tracks according to the their curvature
98 //-----------------------------------------------------------------
7f6ddf58 99 AliITStrackV2 *t=(AliITStrackV2*)o;
6c23ffed 100 //Double_t co=OneOverPt();
101 //Double_t c =OneOverPt();
15dd636f 102 Double_t co=t->GetSigmaY2()*t->GetSigmaZ2();
103 Double_t c =GetSigmaY2()*GetSigmaZ2();
006b5f7f 104 if (c>co) return 1;
105 else if (c<co) return -1;
106 return 0;
107}
108
006b5f7f 109//____________________________________________________________________________
6c94f330 110Bool_t
111AliITStrackV2::PropagateToVertex(const AliESDVertex *v,Double_t d,Double_t x0)
112{
006b5f7f 113 //------------------------------------------------------------------
114 //This function propagates a track to the minimal distance from the origin
6c94f330 115 //------------------------------------------------------------------
116 Double_t bz=GetBz();
117 if (PropagateToDCA(v,bz,kVeryBig))
118 if (AliExternalTrackParam::CorrectForMaterial(d,x0,GetMass())) return kTRUE;
119 return kFALSE;
006b5f7f 120}
121
122//____________________________________________________________________________
6c94f330 123Bool_t AliITStrackV2::
006b5f7f 124GetGlobalXYZat(Double_t xk, Double_t &x, Double_t &y, Double_t &z) const {
125 //------------------------------------------------------------------
126 //This function returns a track position in the global system
127 //------------------------------------------------------------------
6c94f330 128 Double_t r[3];
129 Bool_t rc=GetXYZAt(xk, AliTracker::GetBz(), r);
130 x=r[0]; y=r[1]; z=r[2];
131 return rc;
006b5f7f 132}
133
134//_____________________________________________________________________________
6c94f330 135Double_t AliITStrackV2::GetPredictedChi2(const AliCluster *c) const {
006b5f7f 136 //-----------------------------------------------------------------
137 // This function calculates a predicted chi2 increment.
138 //-----------------------------------------------------------------
6c94f330 139 Double_t p[2]={c->GetY(), c->GetZ()};
140 Double_t cov[3]={c->GetSigmaY2(), 0., c->GetSigmaZ2()};
141 return AliExternalTrackParam::GetPredictedChi2(p,cov);
a9a2d814 142}
143
144//____________________________________________________________________________
6c94f330 145Bool_t AliITStrackV2::PropagateTo(Double_t xk, Double_t d, Double_t x0) {
006b5f7f 146 //------------------------------------------------------------------
147 //This function propagates a track
148 //------------------------------------------------------------------
afd25725 149
6c94f330 150 Double_t oldX=GetX(), oldY=GetY(), oldZ=GetZ();
006b5f7f 151
6c94f330 152 Double_t bz=GetBz();
153 if (!AliExternalTrackParam::PropagateTo(xk,bz)) return kFALSE;
afd25725 154 if (!AliExternalTrackParam::CorrectForMaterial(d,x0,GetMass())) return kFALSE;
006b5f7f 155
dd44614b 156 Double_t x=GetX(), y=GetY(), z=GetZ();
6c94f330 157 if (IsStartedTimeIntegral() && x>oldX) {
158 Double_t l2 = (x-oldX)*(x-oldX) + (y-oldY)*(y-oldY) + (z-oldZ)*(z-oldZ);
f29dbb4b 159 AddTimeStep(TMath::Sqrt(l2));
160 }
f29dbb4b 161
6c94f330 162 return kTRUE;
006b5f7f 163}
164
165//____________________________________________________________________________
afd25725 166Bool_t AliITStrackV2::PropagateToTGeo(Double_t xToGo, Int_t nstep) {
167 //-------------------------------------------------------------------
168 // Propagates the track to a reference plane x=xToGo in n steps.
169 // These n steps are only used to take into account the curvature.
170 // The material is calculated with TGeo. (L.Gaudichet)
171 //-------------------------------------------------------------------
172
173 Double_t startx = GetX(), starty = GetY(), startz = GetZ();
174 Double_t sign = (startx<xToGo) ? -1.:1.;
175 Double_t step = (xToGo-startx)/TMath::Abs(nstep);
176
177 Double_t start[3], end[3], mparam[7], bz = GetBz();
178 Double_t x = startx;
179
180 for (Int_t i=0; i<nstep; i++) {
181
182 GetXYZ(start); //starting global position
183 x += step;
184 if (!GetXYZAt(x, bz, end)) return kFALSE;
185 if (!AliExternalTrackParam::PropagateTo(x, bz)) return kFALSE;
186 AliTracker::MeanMaterialBudget(start, end, mparam);
187 //printf("mparam: %f %f %f %f %f %f %f\n",mparam[0],mparam[1],mparam[2],mparam[3],mparam[4],mparam[5],mparam[6]);
188 if (mparam[1]<900000) {
189 Double_t lengthTimesMeanDensity = sign*mparam[4]*mparam[0];
190 Double_t xOverX0 = mparam[1];
191 //printf("%f %f %f CorrectForMeanMaterial(%f,%f)\n",startx,xToGo,sign,xOverX0,lengthTimesMeanDensity);
192 if (!AliExternalTrackParam::CorrectForMeanMaterial(xOverX0,
193 lengthTimesMeanDensity,GetMass())) return kFALSE;
194 }
195 }
196
197 if (IsStartedTimeIntegral() && GetX()>startx) {
198 Double_t l2 = ( (GetX()-startx)*(GetX()-startx) +
199 (GetY()-starty)*(GetY()-starty) +
200 (GetZ()-startz)*(GetZ()-startz) );
201 AddTimeStep(TMath::Sqrt(l2));
202 }
203
204 return kTRUE;
205}
206
207//____________________________________________________________________________
6c94f330 208Bool_t AliITStrackV2::Update(const AliCluster* c, Double_t chi2, Int_t index)
209{
006b5f7f 210 //------------------------------------------------------------------
211 //This function updates track parameters
212 //------------------------------------------------------------------
6c94f330 213 Double_t p[2]={c->GetY(), c->GetZ()};
214 Double_t cov[3]={c->GetSigmaY2(), 0., c->GetSigmaZ2()};
006b5f7f 215
6c94f330 216 if (!AliExternalTrackParam::Update(p,cov)) return kFALSE;
006b5f7f 217
218 if (!Invariant()) {
6c94f330 219 AliWarning("Wrong invariant !");
220 return kFALSE;
006b5f7f 221 }
222
6c94f330 223 if (chi2<0) return kTRUE;
67c3dcbe 224
006b5f7f 225 Int_t n=GetNumberOfClusters();
226 fIndex[n]=index;
227 SetNumberOfClusters(n+1);
228 SetChi2(GetChi2()+chi2);
229
6c94f330 230 return kTRUE;
006b5f7f 231}
232
6c94f330 233Bool_t AliITStrackV2::Invariant() const {
006b5f7f 234 //------------------------------------------------------------------
235 // This function is for debugging purpose only
236 //------------------------------------------------------------------
7f6ddf58 237 Int_t n=GetNumberOfClusters();
6c94f330 238
239 Double_t sP2=GetParameter()[2];
240 if (TMath::Abs(sP2) >= kAlmost1){
8602c008 241 if (n>fgkWARN) Warning("Invariant","fP2=%f\n",sP2);
6c94f330 242 return kFALSE;
a9a2d814 243 }
6c94f330 244 Double_t sC00=GetCovariance()[0];
245 if (sC00<=0 || sC00>9.) {
8602c008 246 if (n>fgkWARN) Warning("Invariant","fC00=%f\n",sC00);
6c94f330 247 return kFALSE;
a9a2d814 248 }
6c94f330 249 Double_t sC11=GetCovariance()[2];
250 if (sC11<=0 || sC11>9.) {
8602c008 251 if (n>fgkWARN) Warning("Invariant","fC11=%f\n",sC11);
6c94f330 252 return kFALSE;
a9a2d814 253 }
6c94f330 254 Double_t sC22=GetCovariance()[5];
255 if (sC22<=0 || sC22>1.) {
8602c008 256 if (n>fgkWARN) Warning("Invariant","fC22=%f\n",sC22);
6c94f330 257 return kFALSE;
a9a2d814 258 }
6c94f330 259 Double_t sC33=GetCovariance()[9];
260 if (sC33<=0 || sC33>1.) {
8602c008 261 if (n>fgkWARN) Warning("Invariant","fC33=%f\n",sC33);
6c94f330 262 return kFALSE;
a9a2d814 263 }
6c94f330 264 Double_t sC44=GetCovariance()[14];
265 if (sC44<=0 /*|| sC44>6e-5*/) {
8602c008 266 if (n>fgkWARN) Warning("Invariant","fC44=%f\n",sC44);
6c94f330 267 return kFALSE;
14825d5a 268 }
6c94f330 269
270 return kTRUE;
006b5f7f 271}
272
273//____________________________________________________________________________
6c94f330 274Bool_t AliITStrackV2::Propagate(Double_t alp,Double_t xk) {
006b5f7f 275 //------------------------------------------------------------------
276 //This function propagates a track
277 //------------------------------------------------------------------
6c94f330 278 Double_t bz=GetBz();
279 if (!AliExternalTrackParam::Propagate(alp,xk,bz)) return kFALSE;
006b5f7f 280
006b5f7f 281 if (!Invariant()) {
6c94f330 282 AliWarning("Wrong invariant !");
283 return kFALSE;
791f9a2a 284 }
285
6c94f330 286 return kTRUE;
a9a2d814 287}
006b5f7f 288
afd25725 289Bool_t AliITStrackV2::MeanBudgetToPrimVertex(Double_t xyz[3], Double_t step, Double_t &d) const {
290
291 //-------------------------------------------------------------------
292 // Get the mean material budget between the actual point and the
293 // primary vertex. (L.Gaudichet)
294 //-------------------------------------------------------------------
295
296 Double_t cs=TMath::Cos(GetAlpha()), sn=TMath::Sin(GetAlpha());
297 Double_t vertexX = xyz[0]*cs + xyz[1]*sn;
298
299 Int_t nstep = Int_t((GetX()-vertexX)/step);
300 if (nstep<1) nstep = 1;
301 step = (GetX()-vertexX)/nstep;
302
c7719399 303 // Double_t mparam[7], densMean=0, radLength=0, length=0;
304 Double_t mparam[7];
afd25725 305 Double_t p1[3], p2[3], x = GetX(), bz = GetBz();
306 GetXYZ(p1);
307
308 d=0.;
309
310 for (Int_t i=0; i<nstep; i++) {
311 x += step;
312 if (!GetXYZAt(x, bz, p2)) return kFALSE;
313 AliTracker::MeanMaterialBudget(p1, p2, mparam);
314 if (mparam[1]>900000) return kFALSE;
315 d += mparam[1];
316
317 p1[0] = p2[0];
318 p1[1] = p2[1];
319 p1[2] = p2[2];
320 }
321
322 return kTRUE;
323}
324
6c94f330 325Bool_t AliITStrackV2::Improve(Double_t x0,Double_t xyz[3],Double_t ers[3]) {
babd135a 326 //------------------------------------------------------------------
6c94f330 327 //This function improves angular track parameters
babd135a 328 //------------------------------------------------------------------
6c94f330 329 Double_t cs=TMath::Cos(GetAlpha()), sn=TMath::Sin(GetAlpha());
330//Double_t xv = xyz[0]*cs + xyz[1]*sn; // vertex
331 Double_t yv =-xyz[0]*sn + xyz[1]*cs; // in the
332 Double_t zv = xyz[2]; // local frame
babd135a 333
6c94f330 334 Double_t dy = Par(0) - yv, dz = Par(1) - zv;
335 Double_t r2=GetX()*GetX() + dy*dy;
6c23ffed 336 Double_t p2=(1.+ GetTgl()*GetTgl())/(GetSigned1Pt()*GetSigned1Pt());
a9a2d814 337 Double_t beta2=p2/(p2 + GetMass()*GetMass());
338 x0*=TMath::Sqrt((1.+ GetTgl()*GetTgl())/(1.- GetSnp()*GetSnp()));
8676d691 339 Double_t theta2=14.1*14.1/(beta2*p2*1e6)*x0;
340 //Double_t theta2=1.0259e-6*14*14/28/(beta2*p2)*x0*9.36*2.33;
6c94f330 341
342 Double_t cnv=GetBz()*kB2C;
a9a2d814 343 {
6c94f330 344 Double_t dummy = 4/r2 - GetC()*GetC();
345 if (dummy < 0) return kFALSE;
346 Double_t parp = 0.5*(GetC()*GetX() + dy*TMath::Sqrt(dummy));
347 Double_t sigma2p = theta2*(1.- GetSnp()*GetSnp())*(1. + GetTgl()*GetTgl());
348 sigma2p += Cov(0)/r2*(1.- dy*dy/r2)*(1.- dy*dy/r2);
349 sigma2p += ers[1]*ers[1]/r2;
350 sigma2p += 0.25*Cov(14)*cnv*cnv*GetX()*GetX();
00709873 351 Double_t eps2p=sigma2p/(Cov(5) + sigma2p);
6c94f330 352 Par(0) += Cov(3)/(Cov(5) + sigma2p)*(parp - GetSnp());
353 Par(2) = eps2p*GetSnp() + (1 - eps2p)*parp;
354 Cov(5) *= eps2p;
355 Cov(3) *= eps2p;
a9a2d814 356 }
357 {
6c94f330 358 Double_t parl=0.5*GetC()*dz/TMath::ASin(0.5*GetC()*TMath::Sqrt(r2));
359 Double_t sigma2l=theta2;
360 sigma2l += Cov(2)/r2 + Cov(0)*dy*dy*dz*dz/(r2*r2*r2);
361 sigma2l += ers[2]*ers[2]/r2;
362 Double_t eps2l = sigma2l/(Cov(9) + sigma2l);
363 Par(1) += Cov(7 )/(Cov(9) + sigma2l)*(parl - Par(3));
364 Par(4) += Cov(13)/(Cov(9) + sigma2l)*(parl - Par(3));
365 Par(3) = eps2l*Par(3) + (1-eps2l)*parl;
366 Cov(9) *= eps2l;
00709873 367 Cov(13)*= eps2l;
6c94f330 368 Cov(7) *= eps2l;
a9a2d814 369 }
6c94f330 370 if (!Invariant()) return kFALSE;
14825d5a 371
6c94f330 372 return kTRUE;
14825d5a 373}
23efe5f1 374
375void AliITStrackV2::CookdEdx(Double_t low, Double_t up) {
376 //-----------------------------------------------------------------
a9a2d814 377 // This function calculates dE/dX within the "low" and "up" cuts.
378 // Origin: Boris Batyunya, JINR, Boris.Batiounia@cern.ch
23efe5f1 379 //-----------------------------------------------------------------
23efe5f1 380 // The clusters order is: SSD-2, SSD-1, SDD-2, SDD-1, SPD-2, SPD-1
c0dd5278 381
382 Int_t i;
383 Int_t nc=0;
384 for (i=0; i<GetNumberOfClusters(); i++) {
385 Int_t idx=GetClusterIndex(i);
386 idx=(idx&0xf0000000)>>28;
387 if (idx>1) nc++; // Take only SSD and SDD
388 }
23efe5f1 389
a9a2d814 390 Int_t swap;//stupid sorting
23efe5f1 391 do {
392 swap=0;
393 for (i=0; i<nc-1; i++) {
394 if (fdEdxSample[i]<=fdEdxSample[i+1]) continue;
395 Float_t tmp=fdEdxSample[i];
396 fdEdxSample[i]=fdEdxSample[i+1]; fdEdxSample[i+1]=tmp;
397 swap++;
398 }
399 } while (swap);
400
a9a2d814 401 Int_t nl=Int_t(low*nc), nu=Int_t(up*nc); //b.b. to take two lowest dEdX
402 // values from four ones choose
403 // nu=2
23efe5f1 404 Float_t dedx=0;
a9a2d814 405 for (i=nl; i<nu; i++) dedx += fdEdxSample[i];
c0dd5278 406 if (nu-nl>0) dedx /= (nu-nl);
23efe5f1 407
23efe5f1 408 SetdEdx(dedx);
409}
c7bafca9 410
6c94f330 411Double_t AliITStrackV2::GetBz() const {
412 //
413 // returns Bz component of the magnetic field (kG)
414 //
415 if (AliTracker::UniformField()) return AliTracker::GetBz();
416 Double_t r[3]; GetXYZ(r);
417 return AliTracker::GetBz(r);
5773defd 418}
6c94f330 419
8602c008 420//____________________________________________________________________________
421Bool_t AliITStrackV2::
422GetPhiZat(Double_t rk, Double_t &phik, Double_t &zk) const {
423 //------------------------------------------------------------------
424 // This function returns the global cylindrical (phik,zk) of the track
425 // position estimated at the radius rk.
426 // The track curvature is neglected.
427 //------------------------------------------------------------------
428 Double_t d=GetD(0.,0.);
429 if (TMath::Abs(d) > rk) return kFALSE;
430
431 Double_t r=TMath::Sqrt(GetX()*GetX() + GetY()*GetY());
432 Double_t phi=GetAlpha()+TMath::ASin(GetSnp());
433
434 phik=phi+TMath::ASin(d/rk)-TMath::ASin(d/r);
435 zk=GetZ()+GetTgl()*(TMath::Sqrt(rk*rk-d*d) - TMath::Sqrt(r*r-d*d));
436
437 return kTRUE;
438}
439