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Removed ASV version in AliL3FileHandler by another effective i/o method using index...
[u/mrichter/AliRoot.git] / HLT / src / AliL3Fitter.cxx
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3e87ef69 1// @(#) $Id$
1934a2f8 2
3// Author: Anders Vestbo <mailto:vestbo@fi.uib.no>
3e87ef69 4//*-- Copyright &copy ALICE HLT Group
1934a2f8 5
02ddf7f2 6#include "AliL3StandardIncludes.h"
1934a2f8 7#include <math.h>
8
1934a2f8 9#include "AliL3Logging.h"
10#include "AliL3Fitter.h"
11#include "AliL3Vertex.h"
12#include "AliL3Track.h"
13#include "AliL3SpacePointData.h"
355debe1 14#include "AliL3MemHandler.h"
02ddf7f2 15#include "AliL3Transform.h"
3e87ef69 16
17/** \class AliL3Fitter
18<pre>
1934a2f8 19//_____________________________________________________________
20// AliL3Fitter
21//
22// Fit class HLT
3e87ef69 23</pre>
24*/
1934a2f8 25
26ClassImp(AliL3Fitter)
27
28AliL3Fitter::AliL3Fitter(AliL3Vertex *vertex)
29{
30 //constructor
31 fTrack=0;
32 fVertex = vertex;
1934a2f8 33 fVertexConstraint=kTRUE;
3e87ef69 34 memset(fClusters,0,36*6*sizeof(AliL3SpacePointData*));
1934a2f8 35}
36
3e87ef69 37AliL3Fitter::~AliL3Fitter()
38{
39 for(Int_t i=0; i<36; i++)
40 {
41 for(Int_t j=0; j<6; j++)
42 {
43 if(fClusters[i][j])
44 delete fClusters[i][j];
45 }
46 }
47}
48
49void AliL3Fitter::LoadClusters(Char_t *path,Int_t event,Bool_t sp)
1934a2f8 50{
51 Char_t fname[256];
355debe1 52 AliL3MemHandler *clusterfile[36][6];
1934a2f8 53 for(Int_t s=0; s<=35; s++)
54 {
55 for(Int_t p=0; p<6; p++)
56 {
3e87ef69 57 Int_t patch;
58 if(sp==kTRUE)
59 patch=-1;
60 else
61 patch=p;
62 if(fClusters[s][p])
63 delete fClusters[s][p];
64 fClusters[s][p] = 0;
355debe1 65 clusterfile[s][p] = new AliL3MemHandler();
3e87ef69 66 sprintf(fname,"%s/points_%d_%d_%d.raw",path,event,s,patch);
1934a2f8 67 if(!clusterfile[s][p]->SetBinaryInput(fname))
68 {
69 delete clusterfile[s][p];
70 clusterfile[s][p] = 0;
71 continue;
72 }
73 fClusters[s][p] = (AliL3SpacePointData*)clusterfile[s][p]->Allocate();
74 clusterfile[s][p]->Binary2Memory(fNcl[s][p],fClusters[s][p]);
75 clusterfile[s][p]->CloseBinaryInput();
3e87ef69 76 if(sp==kTRUE)
77 break;
1934a2f8 78 }
79 }
80}
81
82Int_t AliL3Fitter::FitHelix(AliL3Track *track)
83{
84 fTrack = track;
85 if(FitCircle())
86 {
87 LOG(AliL3Log::kError,"AliL3Fitter::FitHelix","TrackFit")<<AliL3Log::kDec<<
88 "Problems during circle fit"<<ENDLOG;
89 return 1;
90 }
91 if(FitLine())
92 {
93 LOG(AliL3Log::kError,"AliL3Fitter::FitHelix","TrackFit")<<AliL3Log::kDec<<
94 "Problems during line fit"<<ENDLOG;
95 return 1;
96 }
97 return 0;
98}
99
100Int_t AliL3Fitter::FitCircle()
101{
102 //-----------------------------------------------------------------
103 //Fits circle parameters using algorithm
104 //described by ChErnov and Oskov in Computer Physics
105 //Communications.
106 //
107 //Written in FORTRAN by Jawluen Tang, Physics department , UT-Austin
108 //Moved to C by Pablo Yepes
109 //Moved to AliROOT by ASV.
110 //------------------------------------------------------------------
111
112 Double_t wsum = 0.0 ;
113 Double_t xav = 0.0 ;
114 Double_t yav = 0.0 ;
115
116 //
117 // Loop over hits calculating average
1934a2f8 118 Double_t fXYWeight[(fTrack->GetNHits())];
119 UInt_t *hitnum = fTrack->GetHitNumbers();
120 for(Int_t i=0; i<fTrack->GetNHits(); i++)
121 {
122 UInt_t id = hitnum[i];
123 Int_t slice = (id>>25) & 0x7f;
124 Int_t patch = (id>>22) & 0x7;
125 UInt_t pos = id&0x3fffff;
1934a2f8 126 AliL3SpacePointData *points = fClusters[slice][patch];
3e87ef69 127 fXYWeight[i] = 1./ (Double_t)(points[pos].fSigmaY2 + points[pos].fSigmaY2);
1934a2f8 128 wsum += fXYWeight[i];
129 xav += fXYWeight[i]*points[pos].fX;
130 yav += fXYWeight[i]*points[pos].fY;
131
132 }
133 if (fVertexConstraint == kTRUE)
134 {
135 wsum += fVertex->GetXYWeight() ;
136 xav += fVertex->GetX() ;
137 yav += fVertex->GetY() ;
138 }
139
140 xav = xav / wsum ;
141 yav = yav / wsum ;
142//
143// CALCULATE <X**2>, <XY>, AND <Y**2> WITH <X> = 0, & <Y> = 0
144//
145 Double_t xxav = 0.0 ;
146 Double_t xyav = 0.0 ;
147 Double_t yyav = 0.0 ;
148 Double_t xi, yi ;
3e87ef69 149
1934a2f8 150 for(Int_t i=0; i<fTrack->GetNHits(); i++)
151 {
152 UInt_t id = hitnum[i];
153 Int_t slice = (id>>25) & 0x7f;
154 Int_t patch = (id>>22) & 0x7;
155 UInt_t pos = id&0x3fffff;
156 AliL3SpacePointData *points = fClusters[slice][patch];
3e87ef69 157
1934a2f8 158 xi = points[pos].fX -xav;
159 yi = points[pos].fY - yav ;
160 xxav += xi * xi * fXYWeight[i];
161 xyav += xi * yi * fXYWeight[i];
162 yyav += yi * yi * fXYWeight[i];
163 }
164
165 if (fVertexConstraint == kTRUE)
166 {
167 xi = fVertex->GetX() - xav ;
168 yi = fVertex->GetY() - yav ;
169 xxav += xi * xi * fVertex->GetXYWeight() ;
170 xyav += xi * yi * fVertex->GetXYWeight() ;
171 yyav += yi * yi * fVertex->GetXYWeight() ;
172 }
173 xxav = xxav / wsum ;
174 xyav = xyav / wsum ;
175 yyav = yyav / wsum ;
176//
177//--> ROTATE COORDINATES SO THAT <XY> = 0
178//
179//--> SIGN(C**2 - S**2) = SIGN(XXAV - YYAV) >
180//--> & > ==> NEW : (XXAV-YYAV) > 0
181//--> SIGN(S) = SIGN(XYAV) >
182
183 Double_t a = fabs( xxav - yyav ) ;
184 Double_t b = 4.0 * xyav * xyav ;
185
186 Double_t asqpb = a * a + b ;
187 Double_t rasqpb = sqrt ( asqpb) ;
188
189 Double_t splus = 1.0 + a / rasqpb ;
190 Double_t sminus = b / (asqpb * splus) ;
191
192 splus = sqrt (0.5 * splus ) ;
193 sminus = sqrt (0.5 * sminus) ;
194//
195//-> FIRST REQUIRE : SIGN(C**2 - S**2) = SIGN(XXAV - YYAV)
196//
197 Double_t sinrot, cosrot ;
198 if ( xxav <= yyav ) {
199 cosrot = sminus ;
200 sinrot = splus ;
201 }
202 else {
203 cosrot = splus ;
204 sinrot = sminus ;
205 }
206//
207//-> REQUIRE : SIGN(S) = SIGN(XYAV) * SIGN(C) (ASSUMING SIGN(C) > 0)
208//
209 if ( xyav < 0.0 ) sinrot = - sinrot ;
210//
211//--> WE NOW HAVE THE SMALLEST ANGLE THAT GUARANTEES <X**2> > <Y**2>
212//--> TO GET THE SIGN OF THE CHARGE RIGHT, THE NEW X-AXIS MUST POINT
213//--> OUTWARD FROM THE ORGIN. WE ARE FREE TO CHANGE SIGNS OF BOTH
214//--> COSROT AND SINROT SIMULTANEOUSLY TO ACCOMPLISH THIS.
215//
216//--> CHOOSE SIGN OF C WISELY TO BE ABLE TO GET THE SIGN OF THE CHARGE
217//
218 if ( cosrot*xav+sinrot*yav < 0.0 ) {
219 cosrot = -cosrot ;
220 sinrot = -sinrot ;
221 }
222//
223//-> NOW GET <R**2> AND RSCALE= SQRT(<R**2>)
224//
225 Double_t rrav = xxav + yyav ;
226 Double_t rscale = sqrt(rrav) ;
227
228 xxav = 0.0 ;
229 yyav = 0.0 ;
230 xyav = 0.0 ;
231 Double_t xrrav = 0.0 ;
232 Double_t yrrav = 0.0 ;
233 Double_t rrrrav = 0.0 ;
234
235 Double_t xixi, yiyi, riri, wiriri, xold, yold ;
236
237 for(Int_t i=0; i<fTrack->GetNHits(); i++)
238 {
239 UInt_t id = hitnum[i];
240 Int_t slice = (id>>25) & 0x7f;
241 Int_t patch = (id>>22) & 0x7;
242 UInt_t pos = id&0x3fffff;
243 AliL3SpacePointData *points = fClusters[slice][patch];
244
245 xold = points[pos].fX - xav ;
246 yold = points[pos].fY - yav ;
247 //
248 //--> ROTATE SO THAT <XY> = 0 & DIVIDE BY RSCALE SO THAT <R**2> = 1
249 //
250 xi = ( cosrot * xold + sinrot * yold ) / rscale ;
251 yi = ( -sinrot * xold + cosrot * yold ) / rscale ;
252
253 xixi = xi * xi ;
254 yiyi = yi * yi ;
255 riri = xixi + yiyi ;
256 wiriri = fXYWeight[i] * riri ;
257
258 xyav += fXYWeight[i] * xi * yi ;
259 xxav += fXYWeight[i] * xixi ;
260 yyav += fXYWeight[i] * yiyi ;
261
262 xrrav += wiriri * xi ;
263 yrrav += wiriri * yi ;
264 rrrrav += wiriri * riri ;
265 }
266 //
267// Include vertex if required
268//
269 if (fVertexConstraint == kTRUE)
270 {
271 xold = fVertex->GetX() - xav ;
272 yold = fVertex->GetY() - yav ;
273 //
274 //--> ROTATE SO THAT <XY> = 0 & DIVIDE BY RSCALE SO THAT <R**2> = 1
275 //
276 xi = ( cosrot * xold + sinrot * yold ) / rscale ;
277 yi = ( -sinrot * xold + cosrot * yold ) / rscale ;
278
279 xixi = xi * xi ;
280 yiyi = yi * yi ;
281 riri = xixi + yiyi ;
282 wiriri = fVertex->GetXYWeight() * riri ;
283
284 xyav += fVertex->GetXYWeight() * xi * yi ;
285 xxav += fVertex->GetXYWeight() * xixi ;
286 yyav += fVertex->GetXYWeight() * yiyi ;
287
288 xrrav += wiriri * xi ;
289 yrrav += wiriri * yi ;
290 rrrrav += wiriri * riri ;
291 }
292 //
293 //
294 //
295 //--> DIVIDE BY WSUM TO MAKE AVERAGES
296 //
297 xxav = xxav / wsum ;
298 yyav = yyav / wsum ;
299 xrrav = xrrav / wsum ;
300 yrrav = yrrav / wsum ;
301 rrrrav = rrrrav / wsum ;
302 xyav = xyav / wsum ;
303
304 Int_t const ntry = 5 ;
305//
306//--> USE THESE TO GET THE COEFFICIENTS OF THE 4-TH ORDER POLYNIMIAL
307//--> DON'T PANIC - THE THIRD ORDER TERM IS ZERO !
308//
309 Double_t xrrxrr = xrrav * xrrav ;
310 Double_t yrryrr = yrrav * yrrav ;
311 Double_t rrrrm1 = rrrrav - 1.0 ;
312 Double_t xxyy = xxav * yyav ;
313
314 Double_t c0 = rrrrm1*xxyy - xrrxrr*yyav - yrryrr*xxav ;
315 Double_t c1 = - rrrrm1 + xrrxrr + yrryrr - 4.0*xxyy ;
316 Double_t c2 = 4.0 + rrrrm1 - 4.0*xxyy ;
317 Double_t c4 = - 4.0 ;
318//
319//--> COEFFICIENTS OF THE DERIVATIVE - USED IN NEWTON-RAPHSON ITERATIONS
320//
321 Double_t c2d = 2.0 * c2 ;
322 Double_t c4d = 4.0 * c4 ;
323//
324//--> 0'TH VALUE OF LAMDA - LINEAR INTERPOLATION BETWEEN P(0) & P(YYAV)
325//
326// LAMDA = YYAV * C0 / (C0 + YRRSQ * (XXAV-YYAV))
327 Double_t lamda = 0.0 ;
328 Double_t dlamda = 0.0 ;
329//
330 Double_t chiscl = wsum * rscale * rscale ;
331 Double_t dlamax = 0.001 / chiscl ;
332
333 Double_t p, pd ;
334 for ( int itry = 1 ; itry <= ntry ; itry++ ) {
335 p = c0 + lamda * (c1 + lamda * (c2 + lamda * lamda * c4 )) ;
336 pd = (c1 + lamda * (c2d + lamda * lamda * c4d)) ;
337 dlamda = -p / pd ;
338 lamda = lamda + dlamda ;
339 if (fabs(dlamda)< dlamax) break ;
340 }
341
3e87ef69 342 //Double_t chi2 = (Double_t)(chiscl * lamda) ;
1934a2f8 343
344 //fTrack->SetChiSq1(chi2);
345 // Double_t dchisq = chiscl * dlamda ;
3e87ef69 346 //
347 //--> NOW CALCULATE THE MATRIX ELEMENTS FOR ALPHA, BETA & KAPPA
348 //
1934a2f8 349 Double_t h11 = xxav - lamda ;
350 Double_t h14 = xrrav ;
351 Double_t h22 = yyav - lamda ;
352 Double_t h24 = yrrav ;
353 Double_t h34 = 1.0 + 2.0*lamda ;
354 if ( h11 == 0.0 || h22 == 0.0 ){
355 LOG(AliL3Log::kError,"AliL3Fitter::FitCircle","TrackFit")<<AliL3Log::kDec<<
356 "Problems fitting circle"<<ENDLOG;
357 return 1 ;
358 }
359 Double_t rootsq = (h14*h14)/(h11*h11) + 4.0*h34 ;
360
361 Double_t ratio, kappa, beta ;
362 if ( fabs(h22) > fabs(h24) ) {
363 ratio = h24 / h22 ;
364 rootsq = ratio * ratio + rootsq ;
365 kappa = 1.0 / sqrt(rootsq) ;
366 beta = - ratio * kappa ;
367 }
368 else {
369 ratio = h22 / h24 ;
370 rootsq = 1.0 + ratio * ratio * rootsq ;
371 beta = 1.0 / sqrt(rootsq) ;
372 if ( h24 > 0 ) beta = - beta ;
373 kappa = -ratio * beta ;
374 }
375 Double_t alpha = - (h14/h11) * kappa ;
376//
377//--> transform these into the lab coordinate system
378//--> first get kappa and back to real dimensions
379//
380 Double_t kappa1 = kappa / rscale ;
381 Double_t dbro = 0.5 / kappa1 ;
382//
383//--> next rotate alpha and beta and scale
384//
385 Double_t alphar = (cosrot * alpha - sinrot * beta)* dbro ;
386 Double_t betar = (sinrot * alpha + cosrot * beta)* dbro ;
387//
388//--> then translate by (xav,yav)
389//
390 Double_t acent = (double)(xav - alphar) ;
391 Double_t bcent = (double)(yav - betar ) ;
392 Double_t radius = (double)dbro ;
393//
394// Get charge
395//
396 Int_t q = ( ( yrrav < 0 ) ? 1 : -1 ) ;
397
398 fTrack->SetCharge(q);
399
400//
401// Get other track parameters
402//
403 Double_t x0, y0,phi0,r0,psi,pt ;
404 if ( fVertexConstraint == kTRUE)
405 {
406 //flag = 1 ; // primary track flag
407 x0 = fVertex->GetX() ;
408 y0 = fVertex->GetY() ;
409 phi0 = fVertex->GetPhi() ;
410 r0 = fVertex->GetR() ;
411 fTrack->SetPhi0(phi0);
412 fTrack->SetR0(r0);
413 }
414 else
415 {
416 Int_t lastid=fTrack->GetNHits()-1;
417 UInt_t id = hitnum[lastid];
418 Int_t slice = (id>>25) & 0x7f;
419 Int_t patch = (id>>22) & 0x7;
420 UInt_t pos = id&0x3fffff;
421 AliL3SpacePointData *points = fClusters[slice][patch];
422
423 //flag = 0 ; // primary track flag
424 x0 = points[pos].fX;
425 y0 = points[pos].fY;
426 phi0 = atan2(points[pos].fY,points[pos].fX);
02ddf7f2 427 if ( phi0 < 0 ) phi0 += 2*AliL3Transform::Pi();
1934a2f8 428 r0 = sqrt ( points[pos].fX * points[pos].fX + points[pos].fY*points[pos].fY);
429 fTrack->SetPhi0(phi0);
430 fTrack->SetR0(r0);
431 }
432 //
433 psi = (Double_t)atan2(bcent-y0,acent-x0) ;
02ddf7f2 434 psi = psi + q * 0.5F * AliL3Transform::Pi() ;
435 if ( psi < 0 ) psi = psi + 2*AliL3Transform::Pi();
1934a2f8 436
02ddf7f2 437 pt = (Double_t)(AliL3Transform::GetBFact() * AliL3Transform::GetBField() * radius ) ;
1934a2f8 438 fTrack->SetPsi(psi);
439 fTrack->SetPt(pt);
3e87ef69 440 //fTrack->SetFirstPoint(x0,y0,0);
1934a2f8 441 //
442// Get errors from fast fit
443//
444 //if ( getPara()->getErrors ) getErrorsCircleFit ( acent, bcent, radius ) ;
445//
446 return 0 ;
447
448}
449
450//+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
451// Fit Line in s-z plane
452//+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
453Int_t AliL3Fitter::FitLine ( )
454{
455 //
456 //Initialization
457 //
458 Double_t sum = 0.F ;
459 Double_t ss = 0.F ;
460 Double_t sz = 0.F ;
461 Double_t sss = 0.F ;
462 Double_t ssz = 0.F ;
463 //
464 //find sum , sums ,sumz, sumss
465 //
466 Double_t dx, dy ;
02ddf7f2 467 Double_t radius = (Double_t)(fTrack->GetPt() / ( AliL3Transform::GetBFact() * AliL3Transform::GetBField() ) ) ;
1934a2f8 468
469 //TObjArray *hits = fTrack->GetHits();
470 //Int_t num_of_hits = fTrack->GetNumberOfPoints();
471
472 Double_t fS[(fTrack->GetNHits())];
3e87ef69 473 Double_t *fZWeight = new Double_t[fTrack->GetNHits()];
1934a2f8 474 UInt_t *hitnum = fTrack->GetHitNumbers();
475 if (fVertexConstraint==kTRUE)
476 {
477 UInt_t id = hitnum[0];
478 Int_t slice = (id>>25) & 0x7f;
479 Int_t patch = (id>>22) & 0x7;
480 UInt_t pos = id&0x3fffff;
481 AliL3SpacePointData *points = fClusters[slice][patch];
482
483 dx = points[pos].fX - fVertex->GetX();
3e87ef69 484 dy = points[pos].fY - fVertex->GetY();
1934a2f8 485 }
486 else
487 {
488 UInt_t id = hitnum[0];
489 Int_t slice = (id>>25) & 0x7f;
490 Int_t patch = (id>>22) & 0x7;
491 UInt_t posf = id&0x3fffff;
492 AliL3SpacePointData *pointsf = fClusters[slice][patch];
493 id = hitnum[(fTrack->GetNHits()-1)];
494 slice = (id>>25) & 0x7f;
495 patch = (id>>22) & 0x7;
496 UInt_t posl = id&0x3fffff;
497 AliL3SpacePointData *pointsl = fClusters[slice][patch];
498 dx = pointsf[posf].fX - pointsl[posl].fX;
499 dy = pointsf[posf].fY - pointsl[posl].fY;
500
501 }
502
503 Double_t localPsi = 0.5F * sqrt ( dx*dx + dy*dy ) / radius ;
504 Double_t total_s ;
505
506 if ( fabs(localPsi) < 1. )
507 {
508 total_s = 2.0 * radius * asin ( localPsi ) ;
509 }
510 else
511 {
02ddf7f2 512 total_s = 2.0 * radius * AliL3Transform::Pi() ;
1934a2f8 513 }
514
515 Double_t dpsi,s;
516
517 for(Int_t i=0; i<fTrack->GetNHits(); i++)
518 {
519 UInt_t id = hitnum[i];
520 Int_t slice = (id>>25) & 0x7f;
521 Int_t patch = (id>>22) & 0x7;
522 UInt_t pos = id&0x3fffff;
523 AliL3SpacePointData *points = fClusters[slice][patch];
524
3e87ef69 525 fZWeight[i] = 1./(Double_t)(points[pos].fSigmaZ2);
1934a2f8 526 if(i>0)
527 {
528 id = hitnum[i-1];
529 slice = (id>>25) & 0x7f;
530 patch = (id>>22) & 0x7;
531 UInt_t lastpos = id&0x3fffff;
532 AliL3SpacePointData *lastpoints = fClusters[slice][patch];
533 dx = points[pos].fX -lastpoints[lastpos].fX;
534 dy = points[pos].fY -lastpoints[lastpos].fY;
535 dpsi = 0.5 * (Double_t)sqrt ( dx*dx + dy*dy ) / radius ;
536 fTrack->SetPsierr(dpsi);
537 s = fS[i-1] - 2.0 * radius * (Double_t)asin ( dpsi ) ;
538 fS[i]=s;
539 }
540 else
541 fS[i]=total_s;
542
3e87ef69 543 sum += fZWeight[i];
544 ss += fZWeight[i] * fS[i];
545 sz += fZWeight[i] * points[pos].fZ;
546 sss += fZWeight[i] * fS[i] * fS[i];
547 ssz += fZWeight[i] * fS[i] * points[pos].fZ;
1934a2f8 548
549 }
550
551
552 Double_t chi2,det = sum * sss - ss * ss;
553 if ( fabs(det) < 1e-20)
554 {
555 chi2 = 99999.F ;
556 //fTrack->SetChiSq2(chi2);
557 return 0 ;
558 }
559
560 //Compute the best fitted parameters A,B
561 Double_t tanl,z0,dtanl,dz0;
562
563 tanl = (Double_t)((sum * ssz - ss * sz ) / det );
564 z0 = (Double_t)((sz * sss - ssz * ss ) / det );
565
566 fTrack->SetTgl(tanl);
567 fTrack->SetZ0(z0);
568
569 // calculate chi-square
570
571 chi2 = 0.;
572 Double_t r1 ;
573
574 for(Int_t i=0; i<fTrack->GetNHits(); i++)
575 {
576 UInt_t id = hitnum[i];
577 Int_t slice = (id>>25) & 0x7f;
578 Int_t patch = (id>>22) & 0x7;
579 UInt_t pos = id&0x3fffff;
580 AliL3SpacePointData *points = fClusters[slice][patch];
581 r1 = points[pos].fZ - tanl * fS[i] - z0 ;
3e87ef69 582 chi2 += (Double_t) ( (Double_t)(fZWeight[i]) * (r1 * r1) );
1934a2f8 583 }
584
585 //fTrack->SetChiSq2(chi2);
586 //
587 // calculate estimated variance
588 // varsq=chi/(double(n)-2.)
589 // calculate covariance matrix
590 // siga=sqrt(varsq*sxx/det)
591 // sigb=sqrt(varsq*sum/det)
592 //
593 dtanl = (Double_t) ( sum / det );
594 dz0 = (Double_t) ( sss / det );
595
596 fTrack->SetTglerr(dtanl);
597 fTrack->SetZ0err(dz0);
3e87ef69 598 delete [] fZWeight;
1934a2f8 599 return 0 ;
600}