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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 |
29 | // | |
6b6cba33 | 30 | ////////////////////////////////////////////////////////////////////////////// |
31 | ||
98937d93 | 32 | #include "TMatrixDSym.h" |
33 | #include "TMatrixD.h" | |
8849da04 | 34 | #include "TArrayI.h" |
dfce6628 | 35 | #include "TLinearFitter.h" |
98937d93 | 36 | #include "AliTrackFitterRieman.h" |
24d4520d | 37 | #include "AliLog.h" |
8849da04 | 38 | #include "TTreeStream.h" |
39 | #include "AliRieman.h" | |
40 | #include "AliLog.h" | |
dfce6628 | 41 | #include "TRandom.h" |
98937d93 | 42 | |
43 | ClassImp(AliTrackFitterRieman) | |
44 | ||
8849da04 | 45 | |
98937d93 | 46 | AliTrackFitterRieman::AliTrackFitterRieman(): |
75e3794b | 47 | AliTrackFitter(), |
dfce6628 | 48 | fBCorrection(kFALSE), |
75e3794b | 49 | fAlpha(0.), |
50 | fNUsed(0), | |
51 | fConv(kFALSE), | |
52 | fMaxDelta(3), | |
53 | fRieman(new AliRieman(10000)), // allocate rieman | |
54 | fDebugStream(new TTreeSRedirector("RiemanAlignDebug.root")) | |
98937d93 | 55 | { |
56 | // | |
57 | // default constructor | |
58 | // | |
98937d93 | 59 | } |
60 | ||
61 | ||
62 | AliTrackFitterRieman::AliTrackFitterRieman(AliTrackPointArray *array, Bool_t owner): | |
75e3794b | 63 | AliTrackFitter(array,owner), |
dfce6628 | 64 | fBCorrection(kFALSE), |
75e3794b | 65 | fAlpha(0.), |
66 | fNUsed(0), | |
67 | fConv(kFALSE), | |
68 | fMaxDelta(3), | |
69 | fRieman(new AliRieman(10000)), //allocate rieman | |
70 | fDebugStream(0) | |
98937d93 | 71 | { |
72 | // | |
73 | // Constructor | |
74 | // | |
8849da04 | 75 | if (AliLog::GetDebugLevel("","AliTrackFitterRieman")) fDebugStream = new TTreeSRedirector("RiemanAlignDebug.root"); |
98937d93 | 76 | } |
77 | ||
78 | AliTrackFitterRieman::AliTrackFitterRieman(const AliTrackFitterRieman &rieman): | |
75e3794b | 79 | AliTrackFitter(rieman), |
dfce6628 | 80 | fBCorrection(rieman.fBCorrection), |
75e3794b | 81 | fAlpha(rieman.fAlpha), |
82 | fNUsed(rieman.fNUsed), | |
83 | fConv(rieman.fConv), | |
84 | fMaxDelta(rieman.fMaxDelta), | |
85 | fRieman(new AliRieman(*(rieman.fRieman))), | |
86 | fDebugStream(0) | |
98937d93 | 87 | { |
88 | // | |
89 | // copy constructor | |
90 | // | |
75e3794b | 91 | if (AliLog::GetDebugLevel("","AliTrackFitterRieman")) fDebugStream = new TTreeSRedirector("RiemanAlignDebug.root"); |
98937d93 | 92 | } |
93 | ||
94 | //_____________________________________________________________________________ | |
95 | AliTrackFitterRieman &AliTrackFitterRieman::operator =(const AliTrackFitterRieman& rieman) | |
96 | { | |
6b6cba33 | 97 | // |
98 | // Assignment operator | |
98937d93 | 99 | // |
100 | if(this==&rieman) return *this; | |
101 | ((AliTrackFitter *)this)->operator=(rieman); | |
102 | ||
dfce6628 | 103 | fBCorrection = rieman.fBCorrection; |
8849da04 | 104 | fAlpha = rieman.fAlpha; |
105 | fNUsed = rieman.fNUsed; | |
106 | fConv = rieman.fConv; | |
186e6ced | 107 | fMaxDelta = rieman.fMaxDelta; |
8849da04 | 108 | fRieman = new AliRieman(*(rieman.fRieman)); |
75e3794b | 109 | fDebugStream = 0; |
110 | if (AliLog::GetDebugLevel("","AliTrackFitterRieman")) fDebugStream = new TTreeSRedirector("RiemanAlignDebug.root"); | |
98937d93 | 111 | return *this; |
112 | } | |
113 | ||
8849da04 | 114 | |
115 | AliTrackFitterRieman::~AliTrackFitterRieman(){ | |
116 | // | |
117 | // | |
118 | // | |
119 | delete fRieman; | |
120 | delete fDebugStream; | |
121 | } | |
122 | ||
98937d93 | 123 | void AliTrackFitterRieman::Reset() |
124 | { | |
125 | // Reset the track parameters and | |
126 | // rieman sums | |
6b6cba33 | 127 | // |
98937d93 | 128 | AliTrackFitter::Reset(); |
8849da04 | 129 | fRieman->Reset(); |
98937d93 | 130 | fAlpha = 0.; |
46ae650f | 131 | fNUsed = 0; |
98937d93 | 132 | fConv =kFALSE; |
133 | } | |
134 | ||
cc345ce3 | 135 | Bool_t AliTrackFitterRieman::Fit(const TArrayI *volIds,const TArrayI *volIdsFit, |
98937d93 | 136 | AliAlignObj::ELayerID layerRangeMin, |
8849da04 | 137 | AliAlignObj::ELayerID layerRangeMax) |
98937d93 | 138 | { |
139 | // Fit the track points. The method takes as an input | |
cc345ce3 | 140 | // the set of id's (volids) of the volumes in which |
141 | // one wants to calculate the residuals. | |
142 | // The following parameters are used to define the | |
98937d93 | 143 | // range of volumes to be used in the fitting |
144 | // As a result two AliTrackPointArray's obects are filled. | |
145 | // The first one contains the space points with | |
cc345ce3 | 146 | // volume id's from volids list. The second array of points represents |
147 | // the track extrapolations corresponding to the space points | |
98937d93 | 148 | // in the first array. The two arrays can be used to find |
cc345ce3 | 149 | // the residuals in the volids and consequently construct a |
98937d93 | 150 | // chi2 function to be minimized during the alignment |
151 | // procedures. For the moment the track extrapolation is taken | |
cc345ce3 | 152 | // at the space-point reference plane. The reference plane is |
153 | // found using the covariance matrix of the point | |
154 | // (assuming sigma(x)=0 at the reference coordinate system. | |
dfce6628 | 155 | Int_t debugLevel = AliLog::GetDebugLevel("","AliTrackFitterRieman"); |
156 | Float_t debugRatio = 1./(1.+debugLevel); | |
98937d93 | 157 | |
dfce6628 | 158 | const Int_t kMinPoints =1; |
98937d93 | 159 | Int_t npoints = fPoints->GetNPoints(); |
dfce6628 | 160 | if ( npoints<fMinNPoints) return kFALSE; |
161 | // | |
162 | // fast count points | |
163 | Int_t countFit = 0; | |
164 | for (Int_t ifit=0; ifit<volIdsFit->GetSize(); ifit++){ | |
165 | Int_t volIdFit = volIdsFit->At(ifit); | |
166 | for (Int_t ipoint = 0; ipoint < npoints; ipoint++) | |
167 | if (volIdFit==fPoints->GetVolumeID()[ipoint]) countFit++; | |
168 | } | |
169 | if (countFit<fMinNPoints) return kFALSE; | |
170 | // | |
171 | Int_t countPoint = 0; | |
172 | for (Int_t jpoint=0; jpoint<volIds->GetSize(); jpoint++){ | |
173 | Int_t volIdPoint = volIds->At(jpoint); | |
174 | for (Int_t ipoint = 0; ipoint < npoints; ipoint++) | |
175 | if (volIdPoint==fPoints->GetVolumeID()[ipoint]) countPoint++; | |
176 | } | |
177 | if (countPoint<kMinPoints) return kFALSE; | |
178 | // | |
179 | // | |
180 | ||
181 | Reset(); | |
182 | ||
183 | if (fPoints && AliLog::GetDebugLevel("","AliTrackFitterRieman")>1&& gRandom->Rndm()<debugRatio){ | |
8849da04 | 184 | Int_t nVol = volIds->GetSize(); |
185 | Int_t nVolFit = volIdsFit->GetSize(); | |
186 | Int_t volId = volIds->At(0); | |
187 | (*fDebugStream)<<"PInput"<< | |
188 | "NPoints="<<npoints<< // number of points | |
189 | "VolId="<<volId<< // first vol ID | |
190 | "NVol="<<nVol<< // number of volumes | |
191 | "NvolFit="<<nVolFit<< // number of volumes to fit | |
192 | "fPoints.="<<fPoints<< // input points | |
193 | "\n"; | |
194 | } | |
98937d93 | 195 | |
cc345ce3 | 196 | Bool_t isAlphaCalc = kFALSE; |
46ae650f | 197 | AliTrackPoint p,plocal; |
cc345ce3 | 198 | // fPoints->GetPoint(p,0); |
199 | // fAlpha = TMath::ATan2(p.GetY(),p.GetX()); | |
98937d93 | 200 | |
201 | Int_t npVolId = 0; | |
46ae650f | 202 | fNUsed = 0; |
98937d93 | 203 | Int_t *pindex = new Int_t[npoints]; |
204 | for (Int_t ipoint = 0; ipoint < npoints; ipoint++) | |
205 | { | |
206 | fPoints->GetPoint(p,ipoint); | |
207 | UShort_t iVolId = p.GetVolumeID(); | |
cc345ce3 | 208 | if (FindVolId(volIds,iVolId)) { |
98937d93 | 209 | pindex[npVolId] = ipoint; |
210 | npVolId++; | |
211 | } | |
cc345ce3 | 212 | if (volIdsFit != 0x0) { |
213 | if (!FindVolId(volIdsFit,iVolId)) continue; | |
46ae650f | 214 | } |
215 | else { | |
216 | if (iVolId < AliAlignObj::LayerToVolUID(layerRangeMin,0) || | |
217 | iVolId > AliAlignObj::LayerToVolUID(layerRangeMax, | |
c041444f | 218 | AliAlignObj::LayerSize(layerRangeMax))) continue; |
46ae650f | 219 | } |
cc345ce3 | 220 | if (!isAlphaCalc) { |
221 | fAlpha = p.GetAngle(); | |
222 | isAlphaCalc = kTRUE; | |
223 | } | |
46ae650f | 224 | plocal = p.Rotate(fAlpha); |
186e6ced | 225 | if (TMath::Abs(plocal.GetX())>500 || TMath::Abs(plocal.GetX())<2 || plocal.GetCov()[3]<=0 ||plocal.GetCov()[5]<=0 ){ |
8849da04 | 226 | printf("<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<</n"); |
227 | p.Dump(); | |
228 | plocal.Dump(); | |
229 | printf("Problematic point\n"); | |
230 | printf("<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<</n"); | |
186e6ced | 231 | }else{ |
232 | AddPoint(plocal.GetX(),plocal.GetY(),plocal.GetZ(), | |
233 | TMath::Sqrt(plocal.GetCov()[3]),TMath::Sqrt(plocal.GetCov()[5])); | |
8849da04 | 234 | } |
8849da04 | 235 | // fNUsed++; AddPoint should be responsible |
98937d93 | 236 | } |
237 | ||
8849da04 | 238 | if (npVolId == 0 || fNUsed < fMinNPoints) { |
98937d93 | 239 | delete [] pindex; |
240 | return kFALSE; | |
241 | } | |
242 | ||
243 | Update(); | |
cc345ce3 | 244 | |
98937d93 | 245 | if (!fConv) { |
246 | delete [] pindex; | |
247 | return kFALSE; | |
248 | } | |
249 | ||
250 | if ((fParams[0] == 0) || | |
251 | ((-fParams[2]*fParams[0]+fParams[1]*fParams[1]+1) <= 0)) { | |
252 | delete [] pindex; | |
253 | return kFALSE; | |
254 | } | |
255 | ||
cc345ce3 | 256 | |
257 | if (fNUsed < fMinNPoints) { | |
258 | delete [] pindex; | |
259 | return kFALSE; | |
260 | } | |
261 | ||
46ae650f | 262 | fPVolId = new AliTrackPointArray(npVolId); |
263 | fPTrack = new AliTrackPointArray(npVolId); | |
98937d93 | 264 | AliTrackPoint p2; |
265 | for (Int_t ipoint = 0; ipoint < npVolId; ipoint++) | |
266 | { | |
267 | Int_t index = pindex[ipoint]; | |
268 | fPoints->GetPoint(p,index); | |
186e6ced | 269 | if (GetPCA(p,p2) && ( |
270 | TMath::Abs(p.GetX()-p2.GetX())<fMaxDelta && | |
271 | TMath::Abs(p.GetY()-p2.GetY())<fMaxDelta && | |
272 | TMath::Abs(p.GetZ()-p2.GetZ())<fMaxDelta | |
273 | )) { | |
cc345ce3 | 274 | Float_t xyz[3],xyz2[3]; |
275 | p.GetXYZ(xyz); p2.GetXYZ(xyz2); | |
186e6ced | 276 | // 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 | 277 | fPVolId->AddPoint(ipoint,&p); |
278 | fPTrack->AddPoint(ipoint,&p2); | |
8849da04 | 279 | }else{ |
280 | // what should be default bahavior - | |
281 | delete [] pindex; | |
282 | delete fPVolId; | |
283 | delete fPTrack; | |
284 | fPVolId =0; | |
285 | fPTrack =0; | |
286 | return kFALSE; | |
98937d93 | 287 | } |
288 | } | |
8849da04 | 289 | |
dfce6628 | 290 | if (AliLog::GetDebugLevel("","AliTrackFitterRieman")>0 && gRandom->Rndm()<debugRatio){ |
8849da04 | 291 | // |
292 | // Debug Info | |
293 | // | |
294 | AliTrackPointArray *lPVolId = new AliTrackPointArray(npVolId); | |
295 | AliTrackPointArray *lPTrack = new AliTrackPointArray(npVolId); | |
dfce6628 | 296 | AliTrackPointArray *lPTrackE = new AliTrackPointArray(npVolId); |
8849da04 | 297 | AliRieman * residual = fRieman->MakeResiduals(); |
8849da04 | 298 | for (Int_t ipoint = 0; ipoint < npVolId; ipoint++){ |
dfce6628 | 299 | AliTrackPoint p0, p0local; |
300 | AliTrackPoint pFit, pFitlocal, pFitLocalE; | |
301 | fPVolId->GetPoint(p0,ipoint); | |
302 | Float_t lAngle = p0.GetAngle(); | |
303 | p0local= p0.MasterToLocal(); | |
304 | fPTrack->GetPoint(pFit,ipoint); | |
305 | pFitlocal= pFit.Rotate(lAngle); | |
306 | // | |
307 | Float_t xyz[3], cov[3]; | |
308 | xyz[0] = pFitlocal.GetX(); | |
309 | xyz[1] = pFitlocal.GetY(); | |
310 | xyz[2] = pFitlocal.GetZ(); | |
311 | for (Int_t icov=0; icov<6; icov++) cov[icov]=0; | |
312 | cov[3] = GetErrY2at(xyz[0]); | |
313 | cov[5] = GetErrZ2at(xyz[0]); | |
314 | pFitLocalE.SetXYZ(xyz,cov); | |
315 | // | |
316 | lPVolId->AddPoint(ipoint,&p0local); | |
317 | lPTrack->AddPoint(ipoint,&pFitlocal); | |
318 | lPTrackE->AddPoint(ipoint,&pFitLocalE); | |
8849da04 | 319 | } |
320 | // | |
321 | // debug info | |
322 | // | |
323 | Int_t nVol = volIds->GetSize(); | |
324 | Int_t nVolFit = volIdsFit->GetSize(); | |
325 | Int_t volId = volIds->At(0); | |
326 | Int_t modId =0; | |
327 | Int_t layer = AliAlignObj::VolUIDToLayer(volId,modId); | |
dfce6628 | 328 | Int_t volIdFit = volIdsFit->At(0); |
329 | Int_t modIdFit =0; | |
330 | Int_t layerFit = AliAlignObj::VolUIDToLayer(volIdFit,modIdFit); | |
8849da04 | 331 | |
332 | (*fDebugStream)<<"Fit"<< | |
333 | "VolId="<<volId<< // volume ID | |
334 | "Layer="<<layer<< // layer ID | |
335 | "Module="<<modId<< // module ID | |
dfce6628 | 336 | "LayerFit="<<layerFit<< // layer ID fit |
337 | "ModuleFit="<<modIdFit<< // module ID fit | |
8849da04 | 338 | "NVol="<<nVol<< // number of volumes |
339 | "NvolFit="<<nVolFit<< // number of volumes to fit | |
340 | "Points0.="<<fPVolId<< // original points | |
341 | "Points1.="<<fPTrack<< // fitted points | |
342 | "LPoints0.="<<lPVolId<< // original points - local frame | |
343 | "LPoints1.="<<lPTrack<< // fitted points - local frame | |
dfce6628 | 344 | "LPointsE.="<<lPTrackE<< // fitted points with ext error - local frame |
8849da04 | 345 | "Rieman.="<<this<< // original rieman fit |
346 | "Res.="<<residual<< // residuals of rieman fit | |
347 | "\n"; | |
348 | delete lPVolId; | |
349 | delete lPTrack; | |
350 | delete residual; | |
351 | } | |
98937d93 | 352 | |
353 | delete [] pindex; | |
98937d93 | 354 | return kTRUE; |
355 | } | |
356 | ||
8849da04 | 357 | |
98937d93 | 358 | void AliTrackFitterRieman::AddPoint(Float_t x, Float_t y, Float_t z, Float_t sy, Float_t sz) |
359 | { | |
360 | // | |
8849da04 | 361 | // add point to rieman fitter |
98937d93 | 362 | // |
8849da04 | 363 | fRieman->AddPoint(x,y,z,sy,sz); |
364 | fNUsed = fRieman->GetN(); | |
98937d93 | 365 | } |
366 | ||
8849da04 | 367 | |
368 | ||
98937d93 | 369 | void AliTrackFitterRieman::Update(){ |
370 | // | |
8849da04 | 371 | // |
98937d93 | 372 | // |
8849da04 | 373 | fRieman->Update(); |
374 | fConv = kFALSE; | |
375 | if (fRieman->IsValid()){ | |
376 | for (Int_t ipar=0; ipar<6; ipar++){ | |
377 | fParams[ipar] = fRieman->GetParam()[ipar]; | |
98937d93 | 378 | } |
8849da04 | 379 | fChi2 = fRieman->GetChi2(); |
380 | fNdf = fRieman->GetN()- 2; | |
381 | fNUsed = fRieman->GetN(); | |
382 | fConv = kTRUE; | |
98937d93 | 383 | } |
dfce6628 | 384 | // |
385 | // | |
386 | // | |
387 | TLinearFitter fitY(3,"pol2"); | |
388 | TLinearFitter fitZ(3,"pol2"); | |
389 | for (Int_t ip=0; ip<fRieman->GetN();ip++){ | |
390 | Double_t x = fRieman->GetX()[ip]; | |
391 | fitY.AddPoint(&x,fRieman->GetY()[ip]-fRieman->GetYat(x),1); | |
392 | fitZ.AddPoint(&x,fRieman->GetZ()[ip]-fRieman->GetZat(x),1); | |
393 | } | |
394 | fitY.Eval(); | |
395 | fitZ.Eval(); | |
396 | for (Int_t iparam=0; iparam<3; iparam++){ | |
397 | fCorrY[iparam]=fitY.GetParameter(iparam); | |
398 | fCorrZ[iparam]=fitZ.GetParameter(iparam); | |
399 | } | |
400 | fCorrY[3]=fitY.GetChisquare()/Float_t(fRieman->GetN()-3); | |
401 | fCorrZ[3]=fitZ.GetChisquare()/Float_t(fRieman->GetN()-3); | |
98937d93 | 402 | } |
403 | ||
dfce6628 | 404 | |
405 | ||
6b6cba33 | 406 | //_____________________________________________________________________________ |
98937d93 | 407 | Bool_t AliTrackFitterRieman::GetPCA(const AliTrackPoint &p, AliTrackPoint &p2) const |
408 | { | |
6b6cba33 | 409 | // |
98937d93 | 410 | // Get the closest to a given spacepoint track trajectory point |
411 | // Look for details in the description of the Fit() method | |
6b6cba33 | 412 | // |
98937d93 | 413 | if (!fConv) return kFALSE; |
414 | ||
415 | // First X and Y coordinates | |
416 | Double_t sin = TMath::Sin(fAlpha); | |
417 | Double_t cos = TMath::Cos(fAlpha); | |
418 | // fParam[0] = 1/y0 | |
419 | // fParam[1] = -x0/y0 | |
420 | // fParam[2] = - (R^2 - x0^2 - y0^2)/y0 | |
421 | if (fParams[0] == 0) return kFALSE; | |
cc345ce3 | 422 | // Track parameters in the global coordinate system |
98937d93 | 423 | Double_t x0 = -fParams[1]/fParams[0]*cos - 1./fParams[0]*sin; |
424 | Double_t y0 = 1./fParams[0]*cos - fParams[1]/fParams[0]*sin; | |
425 | if ((-fParams[2]*fParams[0]+fParams[1]*fParams[1]+1) <= 0) return kFALSE; | |
6b6cba33 | 426 | Double_t r = TMath::Sqrt(-fParams[2]*fParams[0]+fParams[1]*fParams[1]+1)/ |
98937d93 | 427 | fParams[0]; |
428 | ||
cc345ce3 | 429 | // Define space-point refence plane |
430 | Double_t alphap = p.GetAngle(); | |
431 | Double_t sinp = TMath::Sin(alphap); | |
432 | Double_t cosp = TMath::Cos(alphap); | |
433 | Double_t x = p.GetX()*cosp + p.GetY()*sinp; | |
434 | Double_t y = p.GetY()*cosp - p.GetX()*sinp; | |
435 | Double_t x0p= x0*cosp + y0*sinp; | |
436 | Double_t y0p= y0*cosp - x0*sinp; | |
6b6cba33 | 437 | if ((r*r - (x-x0p)*(x-x0p))<0) { |
438 | 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 | 439 | return kFALSE; |
440 | } | |
6b6cba33 | 441 | Double_t temp = TMath::Sqrt(r*r - (x-x0p)*(x-x0p)); |
cc345ce3 | 442 | Double_t y1 = y0p + temp; |
443 | Double_t y2 = y0p - temp; | |
444 | Double_t yprime = y1; | |
445 | if(TMath::Abs(y2-y) < TMath::Abs(y1-y)) yprime = y2; | |
446 | ||
447 | // Back to the global coordinate system | |
448 | Double_t xsecond = x*cosp - yprime*sinp; | |
449 | Double_t ysecond = yprime*cosp + x*sinp; | |
450 | ||
451 | // Now Z coordinate and track angles | |
452 | Double_t x2 = xsecond*cos + ysecond*sin; | |
453 | Double_t zsecond = GetZat(x2); | |
454 | Double_t dydx = GetDYat(x2); | |
455 | Double_t dzdx = GetDZat(x2); | |
456 | ||
457 | // Fill the cov matrix of the track extrapolation point | |
458 | Double_t cov[6] = {0,0,0,0,0,0}; | |
459 | Double_t sigmax = 100*100.; | |
460 | cov[0] = sigmax; cov[1] = sigmax*dydx; cov[2] = sigmax*dzdx; | |
461 | cov[3] = sigmax*dydx*dydx; cov[4] = sigmax*dydx*dzdx; | |
462 | cov[5] = sigmax*dzdx*dzdx; | |
463 | ||
dfce6628 | 464 | Double_t sigmay2 = GetErrY2at(x2); |
465 | Double_t sigmaz2 = GetErrZ2at(x2); | |
466 | cov[3] += sigmay2; | |
467 | cov[5] += sigmaz2; | |
468 | ||
469 | ||
cc345ce3 | 470 | Float_t newcov[6]; |
471 | newcov[0] = cov[0]*cos*cos- | |
472 | 2*cov[1]*sin*cos+ | |
473 | cov[3]*sin*sin; | |
474 | newcov[1] = cov[1]*(cos*cos-sin*sin)- | |
475 | (cov[3]-cov[0])*sin*cos; | |
476 | newcov[2] = cov[2]*cos- | |
477 | cov[4]*sin; | |
478 | newcov[3] = cov[0]*sin*sin+ | |
479 | 2*cov[1]*sin*cos+ | |
480 | cov[3]*cos*cos; | |
481 | newcov[4] = cov[4]*cos+ | |
482 | cov[2]*sin; | |
483 | newcov[5] = cov[5]; | |
484 | ||
485 | p2.SetXYZ(xsecond,ysecond,zsecond,newcov); | |
dfce6628 | 486 | Int_t debugLevel = AliLog::GetDebugLevel("","AliTrackFitterRieman"); |
487 | Float_t debugRatio = 1./(1.+debugLevel); | |
488 | if (AliLog::GetDebugLevel("","AliTrackFitterRieman")>0 && gRandom->Rndm()<debugRatio){ | |
8849da04 | 489 | AliTrackPoint lp0(p); |
490 | AliTrackPoint lp2(p2); | |
dfce6628 | 491 | (*fDebugStream)<<"PCA"<< |
8849da04 | 492 | "P0.="<<&lp0<< |
493 | "P2.="<<&lp2<< | |
494 | "\n"; | |
495 | } | |
98937d93 | 496 | return kTRUE; |
497 | } | |
dfce6628 | 498 | |
499 | Double_t AliTrackFitterRieman::GetYat(Double_t x) const { | |
500 | // | |
501 | // get y position at given point | |
502 | // | |
503 | Double_t correction=0; | |
504 | if (fBCorrection){ // systematic effect correction | |
505 | correction = fCorrY[0]+fCorrY[1]*x +fCorrY[2]*x*x; | |
506 | } | |
507 | return fRieman->GetYat(x)+correction; | |
508 | } | |
509 | ||
510 | Double_t AliTrackFitterRieman::GetZat(Double_t x) const { | |
511 | // | |
512 | // get z position at given point | |
513 | // | |
514 | Double_t correction=0; | |
515 | if (fBCorrection){ // systematic effect correction | |
516 | correction = fCorrZ[0]+fCorrZ[1]*x +fCorrZ[2]*x*x; | |
517 | } | |
518 | return fRieman->GetZat(x)+correction; | |
519 | } | |
520 | ||
521 | Double_t AliTrackFitterRieman::GetErrY2at(Double_t x) const { | |
522 | // | |
523 | // get estimate of extrapolation error | |
524 | // | |
525 | Double_t error = fRieman->GetErrY(x); | |
526 | Double_t correction=0; | |
527 | if (fBCorrection){ // everestimate error due systematic effect | |
528 | error *=fCorrY[3]; | |
529 | correction = fCorrY[0]+fCorrY[1]*x +fCorrY[2]*x*x; | |
530 | correction *=correction; | |
531 | } | |
532 | return TMath::Sqrt(error+correction); | |
533 | } | |
534 | ||
535 | Double_t AliTrackFitterRieman::GetErrZ2at(Double_t x) const { | |
536 | // | |
537 | // get estimate of extrapolation error | |
538 | // | |
539 | Double_t error = fRieman->GetErrZ(x)*fCorrZ[3]; | |
540 | Double_t correction=0; | |
541 | if (fBCorrection){ | |
542 | error *= fCorrZ[3]; | |
543 | correction = fCorrZ[0]+fCorrZ[1]*x +fCorrZ[2]*x*x; | |
544 | correction*= correction; | |
545 | } | |
546 | return TMath::Sqrt(error+correction); | |
547 | } | |
548 |