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Little changes to make g++ version 3.2 compile the src library. Problems remaining...
[u/mrichter/AliRoot.git] / HLT / src / AliL3Fitter.cxx
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1934a2f8 1//$Id$
2
3// Author: Anders Vestbo <mailto:vestbo@fi.uib.no>
4//*-- Copyright &copy ASV
5
6#include <math.h>
7
1934a2f8 8#include "AliL3Logging.h"
9#include "AliL3Fitter.h"
10#include "AliL3Vertex.h"
11#include "AliL3Track.h"
12#include "AliL3SpacePointData.h"
355debe1 13#include "AliL3MemHandler.h"
1934a2f8 14
15//_____________________________________________________________
16// AliL3Fitter
17//
18// Fit class HLT
19
20ClassImp(AliL3Fitter)
21
22AliL3Fitter::AliL3Fitter(AliL3Vertex *vertex)
23{
24 //constructor
25 fTrack=0;
26 fVertex = vertex;
27 BFACT = 0.0029980;
28 fVertexConstraint=kTRUE;
29}
30
31void AliL3Fitter::LoadClusters(Char_t *path)
32{
33 Char_t fname[256];
355debe1 34 AliL3MemHandler *clusterfile[36][6];
1934a2f8 35 for(Int_t s=0; s<=35; s++)
36 {
37 for(Int_t p=0; p<6; p++)
38 {
355debe1 39 clusterfile[s][p] = new AliL3MemHandler();
1934a2f8 40 sprintf(fname,"%spoints_%d_%d.raw",path,s,p);
41 if(!clusterfile[s][p]->SetBinaryInput(fname))
42 {
43 delete clusterfile[s][p];
44 clusterfile[s][p] = 0;
45 continue;
46 }
47 fClusters[s][p] = (AliL3SpacePointData*)clusterfile[s][p]->Allocate();
48 clusterfile[s][p]->Binary2Memory(fNcl[s][p],fClusters[s][p]);
49 clusterfile[s][p]->CloseBinaryInput();
50 }
51 }
52}
53
54Int_t AliL3Fitter::FitHelix(AliL3Track *track)
55{
56 fTrack = track;
57 if(FitCircle())
58 {
59 LOG(AliL3Log::kError,"AliL3Fitter::FitHelix","TrackFit")<<AliL3Log::kDec<<
60 "Problems during circle fit"<<ENDLOG;
61 return 1;
62 }
63 if(FitLine())
64 {
65 LOG(AliL3Log::kError,"AliL3Fitter::FitHelix","TrackFit")<<AliL3Log::kDec<<
66 "Problems during line fit"<<ENDLOG;
67 return 1;
68 }
69 return 0;
70}
71
72Int_t AliL3Fitter::FitCircle()
73{
74 //-----------------------------------------------------------------
75 //Fits circle parameters using algorithm
76 //described by ChErnov and Oskov in Computer Physics
77 //Communications.
78 //
79 //Written in FORTRAN by Jawluen Tang, Physics department , UT-Austin
80 //Moved to C by Pablo Yepes
81 //Moved to AliROOT by ASV.
82 //------------------------------------------------------------------
83
84 Double_t wsum = 0.0 ;
85 Double_t xav = 0.0 ;
86 Double_t yav = 0.0 ;
87
88 //
89 // Loop over hits calculating average
90
91 Double_t fXYWeight[(fTrack->GetNHits())];
92 UInt_t *hitnum = fTrack->GetHitNumbers();
93 for(Int_t i=0; i<fTrack->GetNHits(); i++)
94 {
95 UInt_t id = hitnum[i];
96 Int_t slice = (id>>25) & 0x7f;
97 Int_t patch = (id>>22) & 0x7;
98 UInt_t pos = id&0x3fffff;
99
100 AliL3SpacePointData *points = fClusters[slice][patch];
101 fXYWeight[i] = 1./ (Double_t)(points[pos].fXYErr*points[pos].fXYErr + points[pos].fXYErr*points[pos].fXYErr);
102 wsum += fXYWeight[i];
103 xav += fXYWeight[i]*points[pos].fX;
104 yav += fXYWeight[i]*points[pos].fY;
105
106 }
107 if (fVertexConstraint == kTRUE)
108 {
109 wsum += fVertex->GetXYWeight() ;
110 xav += fVertex->GetX() ;
111 yav += fVertex->GetY() ;
112 }
113
114 xav = xav / wsum ;
115 yav = yav / wsum ;
116//
117// CALCULATE <X**2>, <XY>, AND <Y**2> WITH <X> = 0, & <Y> = 0
118//
119 Double_t xxav = 0.0 ;
120 Double_t xyav = 0.0 ;
121 Double_t yyav = 0.0 ;
122 Double_t xi, yi ;
123
124 for(Int_t i=0; i<fTrack->GetNHits(); i++)
125 {
126 UInt_t id = hitnum[i];
127 Int_t slice = (id>>25) & 0x7f;
128 Int_t patch = (id>>22) & 0x7;
129 UInt_t pos = id&0x3fffff;
130 AliL3SpacePointData *points = fClusters[slice][patch];
131 xi = points[pos].fX -xav;
132 yi = points[pos].fY - yav ;
133 xxav += xi * xi * fXYWeight[i];
134 xyav += xi * yi * fXYWeight[i];
135 yyav += yi * yi * fXYWeight[i];
136 }
137
138 if (fVertexConstraint == kTRUE)
139 {
140 xi = fVertex->GetX() - xav ;
141 yi = fVertex->GetY() - yav ;
142 xxav += xi * xi * fVertex->GetXYWeight() ;
143 xyav += xi * yi * fVertex->GetXYWeight() ;
144 yyav += yi * yi * fVertex->GetXYWeight() ;
145 }
146 xxav = xxav / wsum ;
147 xyav = xyav / wsum ;
148 yyav = yyav / wsum ;
149//
150//--> ROTATE COORDINATES SO THAT <XY> = 0
151//
152//--> SIGN(C**2 - S**2) = SIGN(XXAV - YYAV) >
153//--> & > ==> NEW : (XXAV-YYAV) > 0
154//--> SIGN(S) = SIGN(XYAV) >
155
156 Double_t a = fabs( xxav - yyav ) ;
157 Double_t b = 4.0 * xyav * xyav ;
158
159 Double_t asqpb = a * a + b ;
160 Double_t rasqpb = sqrt ( asqpb) ;
161
162 Double_t splus = 1.0 + a / rasqpb ;
163 Double_t sminus = b / (asqpb * splus) ;
164
165 splus = sqrt (0.5 * splus ) ;
166 sminus = sqrt (0.5 * sminus) ;
167//
168//-> FIRST REQUIRE : SIGN(C**2 - S**2) = SIGN(XXAV - YYAV)
169//
170 Double_t sinrot, cosrot ;
171 if ( xxav <= yyav ) {
172 cosrot = sminus ;
173 sinrot = splus ;
174 }
175 else {
176 cosrot = splus ;
177 sinrot = sminus ;
178 }
179//
180//-> REQUIRE : SIGN(S) = SIGN(XYAV) * SIGN(C) (ASSUMING SIGN(C) > 0)
181//
182 if ( xyav < 0.0 ) sinrot = - sinrot ;
183//
184//--> WE NOW HAVE THE SMALLEST ANGLE THAT GUARANTEES <X**2> > <Y**2>
185//--> TO GET THE SIGN OF THE CHARGE RIGHT, THE NEW X-AXIS MUST POINT
186//--> OUTWARD FROM THE ORGIN. WE ARE FREE TO CHANGE SIGNS OF BOTH
187//--> COSROT AND SINROT SIMULTANEOUSLY TO ACCOMPLISH THIS.
188//
189//--> CHOOSE SIGN OF C WISELY TO BE ABLE TO GET THE SIGN OF THE CHARGE
190//
191 if ( cosrot*xav+sinrot*yav < 0.0 ) {
192 cosrot = -cosrot ;
193 sinrot = -sinrot ;
194 }
195//
196//-> NOW GET <R**2> AND RSCALE= SQRT(<R**2>)
197//
198 Double_t rrav = xxav + yyav ;
199 Double_t rscale = sqrt(rrav) ;
200
201 xxav = 0.0 ;
202 yyav = 0.0 ;
203 xyav = 0.0 ;
204 Double_t xrrav = 0.0 ;
205 Double_t yrrav = 0.0 ;
206 Double_t rrrrav = 0.0 ;
207
208 Double_t xixi, yiyi, riri, wiriri, xold, yold ;
209
210 for(Int_t i=0; i<fTrack->GetNHits(); i++)
211 {
212 UInt_t id = hitnum[i];
213 Int_t slice = (id>>25) & 0x7f;
214 Int_t patch = (id>>22) & 0x7;
215 UInt_t pos = id&0x3fffff;
216 AliL3SpacePointData *points = fClusters[slice][patch];
217
218 xold = points[pos].fX - xav ;
219 yold = points[pos].fY - yav ;
220 //
221 //--> ROTATE SO THAT <XY> = 0 & DIVIDE BY RSCALE SO THAT <R**2> = 1
222 //
223 xi = ( cosrot * xold + sinrot * yold ) / rscale ;
224 yi = ( -sinrot * xold + cosrot * yold ) / rscale ;
225
226 xixi = xi * xi ;
227 yiyi = yi * yi ;
228 riri = xixi + yiyi ;
229 wiriri = fXYWeight[i] * riri ;
230
231 xyav += fXYWeight[i] * xi * yi ;
232 xxav += fXYWeight[i] * xixi ;
233 yyav += fXYWeight[i] * yiyi ;
234
235 xrrav += wiriri * xi ;
236 yrrav += wiriri * yi ;
237 rrrrav += wiriri * riri ;
238 }
239 //
240// Include vertex if required
241//
242 if (fVertexConstraint == kTRUE)
243 {
244 xold = fVertex->GetX() - xav ;
245 yold = fVertex->GetY() - yav ;
246 //
247 //--> ROTATE SO THAT <XY> = 0 & DIVIDE BY RSCALE SO THAT <R**2> = 1
248 //
249 xi = ( cosrot * xold + sinrot * yold ) / rscale ;
250 yi = ( -sinrot * xold + cosrot * yold ) / rscale ;
251
252 xixi = xi * xi ;
253 yiyi = yi * yi ;
254 riri = xixi + yiyi ;
255 wiriri = fVertex->GetXYWeight() * riri ;
256
257 xyav += fVertex->GetXYWeight() * xi * yi ;
258 xxav += fVertex->GetXYWeight() * xixi ;
259 yyav += fVertex->GetXYWeight() * yiyi ;
260
261 xrrav += wiriri * xi ;
262 yrrav += wiriri * yi ;
263 rrrrav += wiriri * riri ;
264 }
265 //
266 //
267 //
268 //--> DIVIDE BY WSUM TO MAKE AVERAGES
269 //
270 xxav = xxav / wsum ;
271 yyav = yyav / wsum ;
272 xrrav = xrrav / wsum ;
273 yrrav = yrrav / wsum ;
274 rrrrav = rrrrav / wsum ;
275 xyav = xyav / wsum ;
276
277 Int_t const ntry = 5 ;
278//
279//--> USE THESE TO GET THE COEFFICIENTS OF THE 4-TH ORDER POLYNIMIAL
280//--> DON'T PANIC - THE THIRD ORDER TERM IS ZERO !
281//
282 Double_t xrrxrr = xrrav * xrrav ;
283 Double_t yrryrr = yrrav * yrrav ;
284 Double_t rrrrm1 = rrrrav - 1.0 ;
285 Double_t xxyy = xxav * yyav ;
286
287 Double_t c0 = rrrrm1*xxyy - xrrxrr*yyav - yrryrr*xxav ;
288 Double_t c1 = - rrrrm1 + xrrxrr + yrryrr - 4.0*xxyy ;
289 Double_t c2 = 4.0 + rrrrm1 - 4.0*xxyy ;
290 Double_t c4 = - 4.0 ;
291//
292//--> COEFFICIENTS OF THE DERIVATIVE - USED IN NEWTON-RAPHSON ITERATIONS
293//
294 Double_t c2d = 2.0 * c2 ;
295 Double_t c4d = 4.0 * c4 ;
296//
297//--> 0'TH VALUE OF LAMDA - LINEAR INTERPOLATION BETWEEN P(0) & P(YYAV)
298//
299// LAMDA = YYAV * C0 / (C0 + YRRSQ * (XXAV-YYAV))
300 Double_t lamda = 0.0 ;
301 Double_t dlamda = 0.0 ;
302//
303 Double_t chiscl = wsum * rscale * rscale ;
304 Double_t dlamax = 0.001 / chiscl ;
305
306 Double_t p, pd ;
307 for ( int itry = 1 ; itry <= ntry ; itry++ ) {
308 p = c0 + lamda * (c1 + lamda * (c2 + lamda * lamda * c4 )) ;
309 pd = (c1 + lamda * (c2d + lamda * lamda * c4d)) ;
310 dlamda = -p / pd ;
311 lamda = lamda + dlamda ;
312 if (fabs(dlamda)< dlamax) break ;
313 }
314
315 Double_t chi2 = (Double_t)(chiscl * lamda) ;
316
317 //fTrack->SetChiSq1(chi2);
318 // Double_t dchisq = chiscl * dlamda ;
319//
320//--> NOW CALCULATE THE MATRIX ELEMENTS FOR ALPHA, BETA & KAPPA
321//
322 Double_t h11 = xxav - lamda ;
323 Double_t h14 = xrrav ;
324 Double_t h22 = yyav - lamda ;
325 Double_t h24 = yrrav ;
326 Double_t h34 = 1.0 + 2.0*lamda ;
327 if ( h11 == 0.0 || h22 == 0.0 ){
328 LOG(AliL3Log::kError,"AliL3Fitter::FitCircle","TrackFit")<<AliL3Log::kDec<<
329 "Problems fitting circle"<<ENDLOG;
330 return 1 ;
331 }
332 Double_t rootsq = (h14*h14)/(h11*h11) + 4.0*h34 ;
333
334 Double_t ratio, kappa, beta ;
335 if ( fabs(h22) > fabs(h24) ) {
336 ratio = h24 / h22 ;
337 rootsq = ratio * ratio + rootsq ;
338 kappa = 1.0 / sqrt(rootsq) ;
339 beta = - ratio * kappa ;
340 }
341 else {
342 ratio = h22 / h24 ;
343 rootsq = 1.0 + ratio * ratio * rootsq ;
344 beta = 1.0 / sqrt(rootsq) ;
345 if ( h24 > 0 ) beta = - beta ;
346 kappa = -ratio * beta ;
347 }
348 Double_t alpha = - (h14/h11) * kappa ;
349//
350//--> transform these into the lab coordinate system
351//--> first get kappa and back to real dimensions
352//
353 Double_t kappa1 = kappa / rscale ;
354 Double_t dbro = 0.5 / kappa1 ;
355//
356//--> next rotate alpha and beta and scale
357//
358 Double_t alphar = (cosrot * alpha - sinrot * beta)* dbro ;
359 Double_t betar = (sinrot * alpha + cosrot * beta)* dbro ;
360//
361//--> then translate by (xav,yav)
362//
363 Double_t acent = (double)(xav - alphar) ;
364 Double_t bcent = (double)(yav - betar ) ;
365 Double_t radius = (double)dbro ;
366//
367// Get charge
368//
369 Int_t q = ( ( yrrav < 0 ) ? 1 : -1 ) ;
370
371 fTrack->SetCharge(q);
372
373//
374// Get other track parameters
375//
376 Double_t x0, y0,phi0,r0,psi,pt ;
377 if ( fVertexConstraint == kTRUE)
378 {
379 //flag = 1 ; // primary track flag
380 x0 = fVertex->GetX() ;
381 y0 = fVertex->GetY() ;
382 phi0 = fVertex->GetPhi() ;
383 r0 = fVertex->GetR() ;
384 fTrack->SetPhi0(phi0);
385 fTrack->SetR0(r0);
386 }
387 else
388 {
389 Int_t lastid=fTrack->GetNHits()-1;
390 UInt_t id = hitnum[lastid];
391 Int_t slice = (id>>25) & 0x7f;
392 Int_t patch = (id>>22) & 0x7;
393 UInt_t pos = id&0x3fffff;
394 AliL3SpacePointData *points = fClusters[slice][patch];
395
396 //flag = 0 ; // primary track flag
397 x0 = points[pos].fX;
398 y0 = points[pos].fY;
399 phi0 = atan2(points[pos].fY,points[pos].fX);
400 if ( phi0 < 0 ) phi0 += 2*Pi;
401 r0 = sqrt ( points[pos].fX * points[pos].fX + points[pos].fY*points[pos].fY);
402 fTrack->SetPhi0(phi0);
403 fTrack->SetR0(r0);
404 }
405 //
406 psi = (Double_t)atan2(bcent-y0,acent-x0) ;
407 psi = psi + q * 0.5F * Pi ;
408 if ( psi < 0 ) psi = psi + 2*Pi;
409
410 pt = (Double_t)(BFACT * BField * radius ) ;
411 fTrack->SetPsi(psi);
412 fTrack->SetPt(pt);
413 fTrack->SetFirstPoint(x0,y0,0);
414 //
415// Get errors from fast fit
416//
417 //if ( getPara()->getErrors ) getErrorsCircleFit ( acent, bcent, radius ) ;
418//
419 return 0 ;
420
421}
422
423//+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
424// Fit Line in s-z plane
425//+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
426Int_t AliL3Fitter::FitLine ( )
427{
428 //
429 //Initialization
430 //
431 Double_t sum = 0.F ;
432 Double_t ss = 0.F ;
433 Double_t sz = 0.F ;
434 Double_t sss = 0.F ;
435 Double_t ssz = 0.F ;
436 //
437 //find sum , sums ,sumz, sumss
438 //
439 Double_t dx, dy ;
440 Double_t radius = (Double_t)(fTrack->GetPt() / ( BFACT * BField ) ) ;
441
442 //TObjArray *hits = fTrack->GetHits();
443 //Int_t num_of_hits = fTrack->GetNumberOfPoints();
444
445 Double_t fS[(fTrack->GetNHits())];
446 UInt_t *hitnum = fTrack->GetHitNumbers();
447 if (fVertexConstraint==kTRUE)
448 {
449 UInt_t id = hitnum[0];
450 Int_t slice = (id>>25) & 0x7f;
451 Int_t patch = (id>>22) & 0x7;
452 UInt_t pos = id&0x3fffff;
453 AliL3SpacePointData *points = fClusters[slice][patch];
454
455 dx = points[pos].fX - fVertex->GetX();
456 dy = points[pos].fY - fVertex->GetY() ;
457 }
458 else
459 {
460 UInt_t id = hitnum[0];
461 Int_t slice = (id>>25) & 0x7f;
462 Int_t patch = (id>>22) & 0x7;
463 UInt_t posf = id&0x3fffff;
464 AliL3SpacePointData *pointsf = fClusters[slice][patch];
465 id = hitnum[(fTrack->GetNHits()-1)];
466 slice = (id>>25) & 0x7f;
467 patch = (id>>22) & 0x7;
468 UInt_t posl = id&0x3fffff;
469 AliL3SpacePointData *pointsl = fClusters[slice][patch];
470 dx = pointsf[posf].fX - pointsl[posl].fX;
471 dy = pointsf[posf].fY - pointsl[posl].fY;
472
473 }
474
475 Double_t localPsi = 0.5F * sqrt ( dx*dx + dy*dy ) / radius ;
476 Double_t total_s ;
477
478 if ( fabs(localPsi) < 1. )
479 {
480 total_s = 2.0 * radius * asin ( localPsi ) ;
481 }
482 else
483 {
484 total_s = 2.0 * radius * Pi ;
485 }
486
487 Double_t dpsi,s;
488
489 for(Int_t i=0; i<fTrack->GetNHits(); i++)
490 {
491 UInt_t id = hitnum[i];
492 Int_t slice = (id>>25) & 0x7f;
493 Int_t patch = (id>>22) & 0x7;
494 UInt_t pos = id&0x3fffff;
495 AliL3SpacePointData *points = fClusters[slice][patch];
496
497 if(i>0)
498 {
499 id = hitnum[i-1];
500 slice = (id>>25) & 0x7f;
501 patch = (id>>22) & 0x7;
502 UInt_t lastpos = id&0x3fffff;
503 AliL3SpacePointData *lastpoints = fClusters[slice][patch];
504 dx = points[pos].fX -lastpoints[lastpos].fX;
505 dy = points[pos].fY -lastpoints[lastpos].fY;
506 dpsi = 0.5 * (Double_t)sqrt ( dx*dx + dy*dy ) / radius ;
507 fTrack->SetPsierr(dpsi);
508 s = fS[i-1] - 2.0 * radius * (Double_t)asin ( dpsi ) ;
509 fS[i]=s;
510 }
511 else
512 fS[i]=total_s;
513
514 sum += 1/(points[pos].fZErr*points[pos].fZErr);
515 ss += 1/(points[pos].fZErr*points[pos].fZErr) * fS[i];
516 sz += 1/(points[pos].fZErr*points[pos].fZErr)*points[pos].fZ;
517 sss += 1/(points[pos].fZErr*points[pos].fZErr)* fS[i] * fS[i];
518 ssz += 1/(points[pos].fZErr*points[pos].fZErr) * fS[i] * points[pos].fZ;
519
520 }
521
522
523 Double_t chi2,det = sum * sss - ss * ss;
524 if ( fabs(det) < 1e-20)
525 {
526 chi2 = 99999.F ;
527 //fTrack->SetChiSq2(chi2);
528 return 0 ;
529 }
530
531 //Compute the best fitted parameters A,B
532 Double_t tanl,z0,dtanl,dz0;
533
534 tanl = (Double_t)((sum * ssz - ss * sz ) / det );
535 z0 = (Double_t)((sz * sss - ssz * ss ) / det );
536
537 fTrack->SetTgl(tanl);
538 fTrack->SetZ0(z0);
539
540 // calculate chi-square
541
542 chi2 = 0.;
543 Double_t r1 ;
544
545 for(Int_t i=0; i<fTrack->GetNHits(); i++)
546 {
547 UInt_t id = hitnum[i];
548 Int_t slice = (id>>25) & 0x7f;
549 Int_t patch = (id>>22) & 0x7;
550 UInt_t pos = id&0x3fffff;
551 AliL3SpacePointData *points = fClusters[slice][patch];
552 r1 = points[pos].fZ - tanl * fS[i] - z0 ;
553 chi2 += (Double_t) ( (Double_t)(1/(points[pos].fZErr*points[pos].fZErr)) * (r1 * r1) );
554 }
555
556 //fTrack->SetChiSq2(chi2);
557 //
558 // calculate estimated variance
559 // varsq=chi/(double(n)-2.)
560 // calculate covariance matrix
561 // siga=sqrt(varsq*sxx/det)
562 // sigb=sqrt(varsq*sum/det)
563 //
564 dtanl = (Double_t) ( sum / det );
565 dz0 = (Double_t) ( sss / det );
566
567 fTrack->SetTglerr(dtanl);
568 fTrack->SetZ0err(dz0);
569
570 return 0 ;
571}