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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 | ||
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" |
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 | |
56 | fDebugStream(new TTreeSRedirector("RiemanAlignDebug.root")) | |
98937d93 | 57 | { |
58 | // | |
59 | // default constructor | |
60 | // | |
98937d93 | 61 | } |
62 | ||
63 | ||
64 | AliTrackFitterRieman::AliTrackFitterRieman(AliTrackPointArray *array, Bool_t owner): | |
75e3794b | 65 | AliTrackFitter(array,owner), |
dfce6628 | 66 | fBCorrection(kFALSE), |
75e3794b | 67 | fAlpha(0.), |
68 | fNUsed(0), | |
69 | fConv(kFALSE), | |
70 | fMaxDelta(3), | |
71 | fRieman(new AliRieman(10000)), //allocate rieman | |
72 | fDebugStream(0) | |
98937d93 | 73 | { |
74 | // | |
75 | // Constructor | |
76 | // | |
8849da04 | 77 | if (AliLog::GetDebugLevel("","AliTrackFitterRieman")) fDebugStream = new TTreeSRedirector("RiemanAlignDebug.root"); |
98937d93 | 78 | } |
79 | ||
80 | AliTrackFitterRieman::AliTrackFitterRieman(const AliTrackFitterRieman &rieman): | |
75e3794b | 81 | AliTrackFitter(rieman), |
dfce6628 | 82 | fBCorrection(rieman.fBCorrection), |
75e3794b | 83 | fAlpha(rieman.fAlpha), |
84 | fNUsed(rieman.fNUsed), | |
85 | fConv(rieman.fConv), | |
86 | fMaxDelta(rieman.fMaxDelta), | |
87 | fRieman(new AliRieman(*(rieman.fRieman))), | |
88 | fDebugStream(0) | |
98937d93 | 89 | { |
90 | // | |
91 | // copy constructor | |
92 | // | |
75e3794b | 93 | if (AliLog::GetDebugLevel("","AliTrackFitterRieman")) fDebugStream = new TTreeSRedirector("RiemanAlignDebug.root"); |
98937d93 | 94 | } |
95 | ||
96 | //_____________________________________________________________________________ | |
97 | AliTrackFitterRieman &AliTrackFitterRieman::operator =(const AliTrackFitterRieman& rieman) | |
98 | { | |
6b6cba33 | 99 | // |
100 | // Assignment operator | |
98937d93 | 101 | // |
102 | if(this==&rieman) return *this; | |
103 | ((AliTrackFitter *)this)->operator=(rieman); | |
104 | ||
dfce6628 | 105 | fBCorrection = rieman.fBCorrection; |
8849da04 | 106 | fAlpha = rieman.fAlpha; |
107 | fNUsed = rieman.fNUsed; | |
108 | fConv = rieman.fConv; | |
186e6ced | 109 | fMaxDelta = rieman.fMaxDelta; |
8849da04 | 110 | fRieman = new AliRieman(*(rieman.fRieman)); |
75e3794b | 111 | fDebugStream = 0; |
112 | if (AliLog::GetDebugLevel("","AliTrackFitterRieman")) fDebugStream = new TTreeSRedirector("RiemanAlignDebug.root"); | |
98937d93 | 113 | return *this; |
114 | } | |
115 | ||
8849da04 | 116 | |
117 | AliTrackFitterRieman::~AliTrackFitterRieman(){ | |
118 | // | |
119 | // | |
120 | // | |
121 | delete fRieman; | |
122 | delete fDebugStream; | |
123 | } | |
124 | ||
98937d93 | 125 | void AliTrackFitterRieman::Reset() |
126 | { | |
127 | // Reset the track parameters and | |
128 | // rieman sums | |
6b6cba33 | 129 | // |
98937d93 | 130 | AliTrackFitter::Reset(); |
8849da04 | 131 | fRieman->Reset(); |
98937d93 | 132 | fAlpha = 0.; |
46ae650f | 133 | fNUsed = 0; |
98937d93 | 134 | fConv =kFALSE; |
135 | } | |
136 | ||
cc345ce3 | 137 | Bool_t AliTrackFitterRieman::Fit(const TArrayI *volIds,const TArrayI *volIdsFit, |
98937d93 | 138 | AliAlignObj::ELayerID layerRangeMin, |
8849da04 | 139 | AliAlignObj::ELayerID layerRangeMax) |
98937d93 | 140 | { |
141 | // Fit the track points. The method takes as an input | |
cc345ce3 | 142 | // the set of id's (volids) of the volumes in which |
143 | // one wants to calculate the residuals. | |
144 | // The following parameters are used to define the | |
98937d93 | 145 | // range of volumes to be used in the fitting |
146 | // As a result two AliTrackPointArray's obects are filled. | |
147 | // The first one contains the space points with | |
cc345ce3 | 148 | // volume id's from volids list. The second array of points represents |
149 | // the track extrapolations corresponding to the space points | |
98937d93 | 150 | // in the first array. The two arrays can be used to find |
cc345ce3 | 151 | // the residuals in the volids and consequently construct a |
98937d93 | 152 | // chi2 function to be minimized during the alignment |
153 | // procedures. For the moment the track extrapolation is taken | |
cc345ce3 | 154 | // at the space-point reference plane. The reference plane is |
155 | // found using the covariance matrix of the point | |
156 | // (assuming sigma(x)=0 at the reference coordinate system. | |
dfce6628 | 157 | Int_t debugLevel = AliLog::GetDebugLevel("","AliTrackFitterRieman"); |
158 | Float_t debugRatio = 1./(1.+debugLevel); | |
98937d93 | 159 | |
dfce6628 | 160 | const Int_t kMinPoints =1; |
98937d93 | 161 | Int_t npoints = fPoints->GetNPoints(); |
dfce6628 | 162 | if ( npoints<fMinNPoints) return kFALSE; |
163 | // | |
164 | // fast count points | |
165 | Int_t countFit = 0; | |
166 | for (Int_t ifit=0; ifit<volIdsFit->GetSize(); ifit++){ | |
167 | Int_t volIdFit = volIdsFit->At(ifit); | |
168 | for (Int_t ipoint = 0; ipoint < npoints; ipoint++) | |
169 | if (volIdFit==fPoints->GetVolumeID()[ipoint]) countFit++; | |
170 | } | |
171 | if (countFit<fMinNPoints) return kFALSE; | |
172 | // | |
173 | Int_t countPoint = 0; | |
174 | for (Int_t jpoint=0; jpoint<volIds->GetSize(); jpoint++){ | |
175 | Int_t volIdPoint = volIds->At(jpoint); | |
176 | for (Int_t ipoint = 0; ipoint < npoints; ipoint++) | |
177 | if (volIdPoint==fPoints->GetVolumeID()[ipoint]) countPoint++; | |
178 | } | |
179 | if (countPoint<kMinPoints) return kFALSE; | |
180 | // | |
181 | // | |
182 | ||
183 | Reset(); | |
184 | ||
185 | if (fPoints && AliLog::GetDebugLevel("","AliTrackFitterRieman")>1&& gRandom->Rndm()<debugRatio){ | |
8849da04 | 186 | Int_t nVol = volIds->GetSize(); |
187 | Int_t nVolFit = volIdsFit->GetSize(); | |
188 | Int_t volId = volIds->At(0); | |
189 | (*fDebugStream)<<"PInput"<< | |
190 | "NPoints="<<npoints<< // number of points | |
191 | "VolId="<<volId<< // first vol ID | |
192 | "NVol="<<nVol<< // number of volumes | |
193 | "NvolFit="<<nVolFit<< // number of volumes to fit | |
194 | "fPoints.="<<fPoints<< // input points | |
195 | "\n"; | |
196 | } | |
98937d93 | 197 | |
cc345ce3 | 198 | Bool_t isAlphaCalc = kFALSE; |
46ae650f | 199 | AliTrackPoint p,plocal; |
cc345ce3 | 200 | // fPoints->GetPoint(p,0); |
201 | // fAlpha = TMath::ATan2(p.GetY(),p.GetX()); | |
98937d93 | 202 | |
203 | Int_t npVolId = 0; | |
46ae650f | 204 | fNUsed = 0; |
98937d93 | 205 | Int_t *pindex = new Int_t[npoints]; |
206 | for (Int_t ipoint = 0; ipoint < npoints; ipoint++) | |
207 | { | |
208 | fPoints->GetPoint(p,ipoint); | |
209 | UShort_t iVolId = p.GetVolumeID(); | |
cc345ce3 | 210 | if (FindVolId(volIds,iVolId)) { |
98937d93 | 211 | pindex[npVolId] = ipoint; |
212 | npVolId++; | |
213 | } | |
cc345ce3 | 214 | if (volIdsFit != 0x0) { |
215 | if (!FindVolId(volIdsFit,iVolId)) continue; | |
46ae650f | 216 | } |
217 | else { | |
218 | if (iVolId < AliAlignObj::LayerToVolUID(layerRangeMin,0) || | |
219 | iVolId > AliAlignObj::LayerToVolUID(layerRangeMax, | |
c041444f | 220 | AliAlignObj::LayerSize(layerRangeMax))) continue; |
46ae650f | 221 | } |
cc345ce3 | 222 | if (!isAlphaCalc) { |
223 | fAlpha = p.GetAngle(); | |
224 | isAlphaCalc = kTRUE; | |
225 | } | |
46ae650f | 226 | plocal = p.Rotate(fAlpha); |
186e6ced | 227 | if (TMath::Abs(plocal.GetX())>500 || TMath::Abs(plocal.GetX())<2 || plocal.GetCov()[3]<=0 ||plocal.GetCov()[5]<=0 ){ |
8849da04 | 228 | printf("<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<</n"); |
229 | p.Dump(); | |
230 | plocal.Dump(); | |
231 | printf("Problematic point\n"); | |
232 | printf("<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<</n"); | |
186e6ced | 233 | }else{ |
234 | AddPoint(plocal.GetX(),plocal.GetY(),plocal.GetZ(), | |
235 | TMath::Sqrt(plocal.GetCov()[3]),TMath::Sqrt(plocal.GetCov()[5])); | |
8849da04 | 236 | } |
8849da04 | 237 | // fNUsed++; AddPoint should be responsible |
98937d93 | 238 | } |
239 | ||
8849da04 | 240 | if (npVolId == 0 || fNUsed < fMinNPoints) { |
98937d93 | 241 | delete [] pindex; |
242 | return kFALSE; | |
243 | } | |
244 | ||
245 | Update(); | |
cc345ce3 | 246 | |
98937d93 | 247 | if (!fConv) { |
248 | delete [] pindex; | |
249 | return kFALSE; | |
250 | } | |
251 | ||
252 | if ((fParams[0] == 0) || | |
253 | ((-fParams[2]*fParams[0]+fParams[1]*fParams[1]+1) <= 0)) { | |
254 | delete [] pindex; | |
255 | return kFALSE; | |
256 | } | |
257 | ||
cc345ce3 | 258 | |
259 | if (fNUsed < fMinNPoints) { | |
260 | delete [] pindex; | |
261 | return kFALSE; | |
262 | } | |
263 | ||
46ae650f | 264 | fPVolId = new AliTrackPointArray(npVolId); |
265 | fPTrack = new AliTrackPointArray(npVolId); | |
98937d93 | 266 | AliTrackPoint p2; |
267 | for (Int_t ipoint = 0; ipoint < npVolId; ipoint++) | |
268 | { | |
269 | Int_t index = pindex[ipoint]; | |
270 | fPoints->GetPoint(p,index); | |
186e6ced | 271 | if (GetPCA(p,p2) && ( |
272 | TMath::Abs(p.GetX()-p2.GetX())<fMaxDelta && | |
273 | TMath::Abs(p.GetY()-p2.GetY())<fMaxDelta && | |
274 | TMath::Abs(p.GetZ()-p2.GetZ())<fMaxDelta | |
275 | )) { | |
cc345ce3 | 276 | Float_t xyz[3],xyz2[3]; |
277 | p.GetXYZ(xyz); p2.GetXYZ(xyz2); | |
186e6ced | 278 | // 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 | 279 | fPVolId->AddPoint(ipoint,&p); |
280 | fPTrack->AddPoint(ipoint,&p2); | |
8849da04 | 281 | }else{ |
282 | // what should be default bahavior - | |
283 | delete [] pindex; | |
284 | delete fPVolId; | |
285 | delete fPTrack; | |
286 | fPVolId =0; | |
287 | fPTrack =0; | |
288 | return kFALSE; | |
98937d93 | 289 | } |
290 | } | |
8849da04 | 291 | |
dfce6628 | 292 | if (AliLog::GetDebugLevel("","AliTrackFitterRieman")>0 && gRandom->Rndm()<debugRatio){ |
8849da04 | 293 | // |
294 | // Debug Info | |
295 | // | |
296 | AliTrackPointArray *lPVolId = new AliTrackPointArray(npVolId); | |
297 | AliTrackPointArray *lPTrack = new AliTrackPointArray(npVolId); | |
dfce6628 | 298 | AliTrackPointArray *lPTrackE = new AliTrackPointArray(npVolId); |
8849da04 | 299 | AliRieman * residual = fRieman->MakeResiduals(); |
8849da04 | 300 | for (Int_t ipoint = 0; ipoint < npVolId; ipoint++){ |
dfce6628 | 301 | AliTrackPoint p0, p0local; |
302 | AliTrackPoint pFit, pFitlocal, pFitLocalE; | |
303 | fPVolId->GetPoint(p0,ipoint); | |
304 | Float_t lAngle = p0.GetAngle(); | |
305 | p0local= p0.MasterToLocal(); | |
306 | fPTrack->GetPoint(pFit,ipoint); | |
307 | pFitlocal= pFit.Rotate(lAngle); | |
308 | // | |
14b34be5 | 309 | Float_t xyz[3], cov[6]; |
dfce6628 | 310 | xyz[0] = pFitlocal.GetX(); |
311 | xyz[1] = pFitlocal.GetY(); | |
312 | xyz[2] = pFitlocal.GetZ(); | |
313 | for (Int_t icov=0; icov<6; icov++) cov[icov]=0; | |
314 | cov[3] = GetErrY2at(xyz[0]); | |
315 | cov[5] = GetErrZ2at(xyz[0]); | |
316 | pFitLocalE.SetXYZ(xyz,cov); | |
317 | // | |
318 | lPVolId->AddPoint(ipoint,&p0local); | |
319 | lPTrack->AddPoint(ipoint,&pFitlocal); | |
320 | lPTrackE->AddPoint(ipoint,&pFitLocalE); | |
8849da04 | 321 | } |
322 | // | |
323 | // debug info | |
324 | // | |
325 | Int_t nVol = volIds->GetSize(); | |
326 | Int_t nVolFit = volIdsFit->GetSize(); | |
327 | Int_t volId = volIds->At(0); | |
328 | Int_t modId =0; | |
329 | Int_t layer = AliAlignObj::VolUIDToLayer(volId,modId); | |
dfce6628 | 330 | Int_t volIdFit = volIdsFit->At(0); |
331 | Int_t modIdFit =0; | |
332 | Int_t layerFit = AliAlignObj::VolUIDToLayer(volIdFit,modIdFit); | |
8849da04 | 333 | |
334 | (*fDebugStream)<<"Fit"<< | |
335 | "VolId="<<volId<< // volume ID | |
336 | "Layer="<<layer<< // layer ID | |
337 | "Module="<<modId<< // module ID | |
dfce6628 | 338 | "LayerFit="<<layerFit<< // layer ID fit |
339 | "ModuleFit="<<modIdFit<< // module ID fit | |
8849da04 | 340 | "NVol="<<nVol<< // number of volumes |
341 | "NvolFit="<<nVolFit<< // number of volumes to fit | |
342 | "Points0.="<<fPVolId<< // original points | |
343 | "Points1.="<<fPTrack<< // fitted points | |
344 | "LPoints0.="<<lPVolId<< // original points - local frame | |
345 | "LPoints1.="<<lPTrack<< // fitted points - local frame | |
dfce6628 | 346 | "LPointsE.="<<lPTrackE<< // fitted points with ext error - local frame |
8849da04 | 347 | "Rieman.="<<this<< // original rieman fit |
348 | "Res.="<<residual<< // residuals of rieman fit | |
349 | "\n"; | |
350 | delete lPVolId; | |
351 | delete lPTrack; | |
352 | delete residual; | |
353 | } | |
98937d93 | 354 | |
355 | delete [] pindex; | |
98937d93 | 356 | return kTRUE; |
357 | } | |
358 | ||
8849da04 | 359 | |
98937d93 | 360 | void AliTrackFitterRieman::AddPoint(Float_t x, Float_t y, Float_t z, Float_t sy, Float_t sz) |
361 | { | |
362 | // | |
8849da04 | 363 | // add point to rieman fitter |
98937d93 | 364 | // |
8849da04 | 365 | fRieman->AddPoint(x,y,z,sy,sz); |
366 | fNUsed = fRieman->GetN(); | |
98937d93 | 367 | } |
368 | ||
8849da04 | 369 | |
370 | ||
98937d93 | 371 | void AliTrackFitterRieman::Update(){ |
372 | // | |
8849da04 | 373 | // |
98937d93 | 374 | // |
8849da04 | 375 | fRieman->Update(); |
376 | fConv = kFALSE; | |
377 | if (fRieman->IsValid()){ | |
378 | for (Int_t ipar=0; ipar<6; ipar++){ | |
379 | fParams[ipar] = fRieman->GetParam()[ipar]; | |
98937d93 | 380 | } |
8849da04 | 381 | fChi2 = fRieman->GetChi2(); |
382 | fNdf = fRieman->GetN()- 2; | |
383 | fNUsed = fRieman->GetN(); | |
384 | fConv = kTRUE; | |
98937d93 | 385 | } |
dfce6628 | 386 | // |
387 | // | |
388 | // | |
389 | TLinearFitter fitY(3,"pol2"); | |
390 | TLinearFitter fitZ(3,"pol2"); | |
391 | for (Int_t ip=0; ip<fRieman->GetN();ip++){ | |
392 | Double_t x = fRieman->GetX()[ip]; | |
393 | fitY.AddPoint(&x,fRieman->GetY()[ip]-fRieman->GetYat(x),1); | |
394 | fitZ.AddPoint(&x,fRieman->GetZ()[ip]-fRieman->GetZat(x),1); | |
395 | } | |
396 | fitY.Eval(); | |
397 | fitZ.Eval(); | |
398 | for (Int_t iparam=0; iparam<3; iparam++){ | |
399 | fCorrY[iparam]=fitY.GetParameter(iparam); | |
400 | fCorrZ[iparam]=fitZ.GetParameter(iparam); | |
401 | } | |
402 | fCorrY[3]=fitY.GetChisquare()/Float_t(fRieman->GetN()-3); | |
403 | fCorrZ[3]=fitZ.GetChisquare()/Float_t(fRieman->GetN()-3); | |
98937d93 | 404 | } |
405 | ||
dfce6628 | 406 | |
407 | ||
6b6cba33 | 408 | //_____________________________________________________________________________ |
98937d93 | 409 | Bool_t AliTrackFitterRieman::GetPCA(const AliTrackPoint &p, AliTrackPoint &p2) const |
410 | { | |
6b6cba33 | 411 | // |
98937d93 | 412 | // Get the closest to a given spacepoint track trajectory point |
413 | // Look for details in the description of the Fit() method | |
6b6cba33 | 414 | // |
98937d93 | 415 | if (!fConv) return kFALSE; |
416 | ||
417 | // First X and Y coordinates | |
418 | Double_t sin = TMath::Sin(fAlpha); | |
419 | Double_t cos = TMath::Cos(fAlpha); | |
420 | // fParam[0] = 1/y0 | |
421 | // fParam[1] = -x0/y0 | |
422 | // fParam[2] = - (R^2 - x0^2 - y0^2)/y0 | |
423 | if (fParams[0] == 0) return kFALSE; | |
cc345ce3 | 424 | // Track parameters in the global coordinate system |
98937d93 | 425 | Double_t x0 = -fParams[1]/fParams[0]*cos - 1./fParams[0]*sin; |
426 | Double_t y0 = 1./fParams[0]*cos - fParams[1]/fParams[0]*sin; | |
427 | if ((-fParams[2]*fParams[0]+fParams[1]*fParams[1]+1) <= 0) return kFALSE; | |
6b6cba33 | 428 | Double_t r = TMath::Sqrt(-fParams[2]*fParams[0]+fParams[1]*fParams[1]+1)/ |
98937d93 | 429 | fParams[0]; |
430 | ||
cc345ce3 | 431 | // Define space-point refence plane |
432 | Double_t alphap = p.GetAngle(); | |
433 | Double_t sinp = TMath::Sin(alphap); | |
434 | Double_t cosp = TMath::Cos(alphap); | |
435 | Double_t x = p.GetX()*cosp + p.GetY()*sinp; | |
436 | Double_t y = p.GetY()*cosp - p.GetX()*sinp; | |
437 | Double_t x0p= x0*cosp + y0*sinp; | |
438 | Double_t y0p= y0*cosp - x0*sinp; | |
6b6cba33 | 439 | if ((r*r - (x-x0p)*(x-x0p))<0) { |
440 | 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 | 441 | return kFALSE; |
442 | } | |
6b6cba33 | 443 | Double_t temp = TMath::Sqrt(r*r - (x-x0p)*(x-x0p)); |
cc345ce3 | 444 | Double_t y1 = y0p + temp; |
445 | Double_t y2 = y0p - temp; | |
446 | Double_t yprime = y1; | |
447 | if(TMath::Abs(y2-y) < TMath::Abs(y1-y)) yprime = y2; | |
448 | ||
449 | // Back to the global coordinate system | |
450 | Double_t xsecond = x*cosp - yprime*sinp; | |
451 | Double_t ysecond = yprime*cosp + x*sinp; | |
452 | ||
453 | // Now Z coordinate and track angles | |
454 | Double_t x2 = xsecond*cos + ysecond*sin; | |
455 | Double_t zsecond = GetZat(x2); | |
456 | Double_t dydx = GetDYat(x2); | |
457 | Double_t dzdx = GetDZat(x2); | |
458 | ||
459 | // Fill the cov matrix of the track extrapolation point | |
460 | Double_t cov[6] = {0,0,0,0,0,0}; | |
461 | Double_t sigmax = 100*100.; | |
462 | cov[0] = sigmax; cov[1] = sigmax*dydx; cov[2] = sigmax*dzdx; | |
463 | cov[3] = sigmax*dydx*dydx; cov[4] = sigmax*dydx*dzdx; | |
464 | cov[5] = sigmax*dzdx*dzdx; | |
465 | ||
dfce6628 | 466 | Double_t sigmay2 = GetErrY2at(x2); |
467 | Double_t sigmaz2 = GetErrZ2at(x2); | |
468 | cov[3] += sigmay2; | |
469 | cov[5] += sigmaz2; | |
470 | ||
471 | ||
cc345ce3 | 472 | Float_t newcov[6]; |
473 | newcov[0] = cov[0]*cos*cos- | |
474 | 2*cov[1]*sin*cos+ | |
475 | cov[3]*sin*sin; | |
476 | newcov[1] = cov[1]*(cos*cos-sin*sin)- | |
477 | (cov[3]-cov[0])*sin*cos; | |
478 | newcov[2] = cov[2]*cos- | |
479 | cov[4]*sin; | |
480 | newcov[3] = cov[0]*sin*sin+ | |
481 | 2*cov[1]*sin*cos+ | |
482 | cov[3]*cos*cos; | |
483 | newcov[4] = cov[4]*cos+ | |
484 | cov[2]*sin; | |
485 | newcov[5] = cov[5]; | |
486 | ||
487 | p2.SetXYZ(xsecond,ysecond,zsecond,newcov); | |
dfce6628 | 488 | Int_t debugLevel = AliLog::GetDebugLevel("","AliTrackFitterRieman"); |
489 | Float_t debugRatio = 1./(1.+debugLevel); | |
490 | if (AliLog::GetDebugLevel("","AliTrackFitterRieman")>0 && gRandom->Rndm()<debugRatio){ | |
8849da04 | 491 | AliTrackPoint lp0(p); |
492 | AliTrackPoint lp2(p2); | |
dfce6628 | 493 | (*fDebugStream)<<"PCA"<< |
8849da04 | 494 | "P0.="<<&lp0<< |
495 | "P2.="<<&lp2<< | |
496 | "\n"; | |
497 | } | |
98937d93 | 498 | return kTRUE; |
499 | } | |
dfce6628 | 500 | |
501 | Double_t AliTrackFitterRieman::GetYat(Double_t x) const { | |
502 | // | |
503 | // get y position at given point | |
504 | // | |
505 | Double_t correction=0; | |
506 | if (fBCorrection){ // systematic effect correction | |
507 | correction = fCorrY[0]+fCorrY[1]*x +fCorrY[2]*x*x; | |
508 | } | |
509 | return fRieman->GetYat(x)+correction; | |
510 | } | |
511 | ||
512 | Double_t AliTrackFitterRieman::GetZat(Double_t x) const { | |
513 | // | |
514 | // get z position at given point | |
515 | // | |
516 | Double_t correction=0; | |
517 | if (fBCorrection){ // systematic effect correction | |
518 | correction = fCorrZ[0]+fCorrZ[1]*x +fCorrZ[2]*x*x; | |
519 | } | |
520 | return fRieman->GetZat(x)+correction; | |
521 | } | |
522 | ||
523 | Double_t AliTrackFitterRieman::GetErrY2at(Double_t x) const { | |
524 | // | |
525 | // get estimate of extrapolation error | |
526 | // | |
527 | Double_t error = fRieman->GetErrY(x); | |
528 | Double_t correction=0; | |
529 | if (fBCorrection){ // everestimate error due systematic effect | |
530 | error *=fCorrY[3]; | |
531 | correction = fCorrY[0]+fCorrY[1]*x +fCorrY[2]*x*x; | |
532 | correction *=correction; | |
533 | } | |
534 | return TMath::Sqrt(error+correction); | |
535 | } | |
536 | ||
537 | Double_t AliTrackFitterRieman::GetErrZ2at(Double_t x) const { | |
538 | // | |
539 | // get estimate of extrapolation error | |
540 | // | |
541 | Double_t error = fRieman->GetErrZ(x)*fCorrZ[3]; | |
542 | Double_t correction=0; | |
543 | if (fBCorrection){ | |
544 | error *= fCorrZ[3]; | |
545 | correction = fCorrZ[0]+fCorrZ[1]*x +fCorrZ[2]*x*x; | |
546 | correction*= correction; | |
547 | } | |
548 | return TMath::Sqrt(error+correction); | |
549 | } | |
550 |