Fixed size array instead of poiner (valgrind)
[u/mrichter/AliRoot.git] / ITS / AliITSMultReconstructor.cxx
CommitLineData
ac903f1b 1//____________________________________________________________________
2//
3// AliITSMultReconstructor - find clusters in the pixels (theta and
4// phi) and tracklets.
5//
6// These can be used to extract charged particles multiplcicity from the ITS.
7//
8// A tracklet consist of two ITS clusters, one in the first pixel
9// layer and one in the second. The clusters are associates if the
10// differencies in Phi (azimuth) and Zeta (longitudinal) are inside
11// a fiducial volume. In case of multiple candidates it is selected the
12// candidate with minimum distance in Phi.
13// The parameter AssociationChoice allows to control if two clusters
14// in layer 2 can be associated to the same cluster in layer 1 or not.
15//
16// -----------------------------------------------------------------
17//
3ef75756 18// NOTE: The cuts on phi and zeta depends on the interacting system (p-p
19// or Pb-Pb). Please, check the file AliITSMultReconstructor.h and be
20// sure that SetPhiWindow and SetZetaWindow are defined accordingly.
ac903f1b 21//
3ef75756 22//
23//
ac903f1b 24//
25//____________________________________________________________________
26
27#include "AliITSMultReconstructor.h"
28
29#include "TTree.h"
30#include "TH1F.h"
31#include "TH2F.h"
32
b51872de 33#include "AliITSRecPoint.h"
ac903f1b 34#include "AliITSgeom.h"
35#include "AliLog.h"
36
37//____________________________________________________________________
0762f3a8 38ClassImp(AliITSMultReconstructor)
ac903f1b 39
3ef75756 40
ac903f1b 41//____________________________________________________________________
42AliITSMultReconstructor::AliITSMultReconstructor() {
3ef75756 43 // Method to reconstruct the charged particles multiplicity with the
44 // SPD (tracklets).
ac903f1b 45
46 fGeometry =0;
47
48 SetHistOn();
49 SetPhiWindow();
50 SetZetaWindow();
51 SetOnlyOneTrackletPerC2();
52
53 fClustersLay1 = new Float_t*[300000];
54 fClustersLay2 = new Float_t*[300000];
55 fTracklets = new Float_t*[300000];
56 fAssociationFlag = new Bool_t[300000];
57
58 for(Int_t i=0; i<300000; i++) {
59 fClustersLay1[i] = new Float_t[3];
60 fClustersLay2[i] = new Float_t[3];
61 fTracklets[i] = new Float_t[3];
62 fAssociationFlag[i] = kFALSE;
63 }
64
65 // definition of histograms
ddced3c8 66 fhClustersDPhiAcc = new TH1F("dphiacc", "dphi", 100,-0.1,0.1);
67 fhClustersDPhiAcc->SetDirectory(0);
68 fhClustersDThetaAcc = new TH1F("dthetaacc","dtheta",100,-0.1,0.1);
69 fhClustersDThetaAcc->SetDirectory(0);
70 fhClustersDZetaAcc = new TH1F("dzetaacc","dzeta",100,-1.,1.);
71 fhClustersDZetaAcc->SetDirectory(0);
72
73 fhDPhiVsDZetaAcc = new TH2F("dphiVsDzetaacc","",100,-1.,1.,100,-0.1,0.1);
74 fhDPhiVsDZetaAcc->SetDirectory(0);
75 fhDPhiVsDThetaAcc = new TH2F("dphiVsDthetaAcc","",100,-0.1,0.1,100,-0.1,0.1);
ac903f1b 76 fhDPhiVsDThetaAcc->SetDirectory(0);
77
ddced3c8 78 fhClustersDPhiAll = new TH1F("dphiall", "dphi", 100,-0.5,0.5);
79 fhClustersDPhiAll->SetDirectory(0);
80 fhClustersDThetaAll = new TH1F("dthetaall","dtheta",100,-0.5,0.5);
81 fhClustersDThetaAll->SetDirectory(0);
82 fhClustersDZetaAll = new TH1F("dzetaall","dzeta",100,-5.,5.);
83 fhClustersDZetaAll->SetDirectory(0);
84
85 fhDPhiVsDZetaAll = new TH2F("dphiVsDzetaall","",100,-5.,5.,100,-0.5,0.5);
86 fhDPhiVsDZetaAll->SetDirectory(0);
87 fhDPhiVsDThetaAll = new TH2F("dphiVsDthetaAll","",100,-0.5,0.5,100,-0.5,0.5);
88 fhDPhiVsDThetaAll->SetDirectory(0);
89
90 fhetaTracklets = new TH1F("etaTracklets", "eta", 100,-2.,2.);
ddced3c8 91 fhphiTracklets = new TH1F("phiTracklets", "phi", 100,-3.14159,3.14159);
ddced3c8 92 fhetaClustersLay1 = new TH1F("etaClustersLay1", "etaCl1", 100,-2.,2.);
ddced3c8 93 fhphiClustersLay1 = new TH1F("phiClustersLay1", "phiCl1", 100,-3.141,3.141);
3ef75756 94
ac903f1b 95}
ddced3c8 96
3ef75756 97//______________________________________________________________________
98AliITSMultReconstructor::AliITSMultReconstructor(const AliITSMultReconstructor &mr) : TObject(mr) {
99 // Copy constructor
100 // Copies are not allowed. The method is protected to avoid misuse.
101 Error("AliITSMultReconstructor","Copy constructor not allowed\n");
102}
103
104//______________________________________________________________________
105AliITSMultReconstructor& AliITSMultReconstructor::operator=(const AliITSMultReconstructor& /* mr */){
106 // Assignment operator
107 // Assignment is not allowed. The method is protected to avoid misuse.
108 Error("= operator","Assignment operator not allowed\n");
109 return *this;
110}
111
112//______________________________________________________________________
113AliITSMultReconstructor::~AliITSMultReconstructor(){
114 // Destructor
115 if(fhClustersDPhiAcc)delete fhClustersDPhiAcc;
116 if(fhClustersDThetaAcc)delete fhClustersDThetaAcc;
117 if(fhClustersDZetaAcc)delete fhClustersDZetaAcc;
118 if(fhClustersDPhiAll)delete fhClustersDPhiAll;
119 if(fhClustersDThetaAll)delete fhClustersDThetaAll;
120 if(fhClustersDZetaAll)delete fhClustersDZetaAll;
121 if(fhDPhiVsDThetaAll)delete fhDPhiVsDThetaAll;
122 if(fhDPhiVsDThetaAcc)delete fhDPhiVsDThetaAcc;
123 if(fhDPhiVsDZetaAll)delete fhDPhiVsDZetaAll;
124 if(fhDPhiVsDZetaAcc)delete fhDPhiVsDZetaAcc;
125 if(fhetaTracklets)delete fhetaTracklets;
126 if(fhphiTracklets)delete fhphiTracklets;
127 if(fhetaClustersLay1)delete fhetaClustersLay1;
128 if(fhphiClustersLay1)delete fhphiClustersLay1;
129 if(fClustersLay1){
130 for(Int_t i=0; i<300000; i++) {
131 delete [] fClustersLay1[i];
132 delete [] fClustersLay2[i];
133 delete [] fTracklets[i];
134 }
135 delete fClustersLay1;
136 delete fClustersLay2;
137 delete fTracklets;
ddced3c8 138 }
3ef75756 139 if(fAssociationFlag)delete fAssociationFlag;
ddced3c8 140}
ac903f1b 141
142//____________________________________________________________________
143void
144AliITSMultReconstructor::Reconstruct(TTree* clusterTree, Float_t* vtx, Float_t* /* vtxRes*/) {
145 //
146 // - calls LoadClusterArray that finds the position of the clusters
147 // (in global coord)
148 // - convert the cluster coordinates to theta, phi (seen from the
149 // interaction vertex). The third coordinate is used for ....
150 // - makes an array of tracklets
151 //
152 // After this method has been called, the clusters of the two layers
153 // and the tracklets can be retrieved by calling the Get'er methods.
154
ac903f1b 155 // reset counters
156 fNClustersLay1 = 0;
157 fNClustersLay2 = 0;
158 fNTracklets = 0;
159
160 // loading the clusters
161 LoadClusterArrays(clusterTree);
3ef75756 162
ac903f1b 163 // find the tracklets
164 AliDebug(1,"Looking for tracklets... ");
165
166 //###########################################################
167 // Loop on layer 1 : finding theta, phi and z
168 for (Int_t iC1=0; iC1<fNClustersLay1; iC1++) {
169 Float_t x = fClustersLay1[iC1][0] - vtx[0];
170 Float_t y = fClustersLay1[iC1][1] - vtx[1];
171 Float_t z = fClustersLay1[iC1][2] - vtx[2];
ddced3c8 172
ac903f1b 173 Float_t r = TMath::Sqrt(TMath::Power(x,2) +
174 TMath::Power(y,2) +
175 TMath::Power(z,2));
176
177 fClustersLay1[iC1][0] = TMath::ACos(z/r); // Store Theta
ddced3c8 178 fClustersLay1[iC1][1] = TMath::ATan2(x,y); // Store Phi
ac903f1b 179 fClustersLay1[iC1][2] = z/r; // Store scaled z
ddced3c8 180 if (fHistOn) {
181 Float_t eta=fClustersLay1[iC1][0];
182 eta= TMath::Tan(eta/2.);
183 eta=-TMath::Log(eta);
184 fhetaClustersLay1->Fill(eta);
185 fhphiClustersLay1->Fill(fClustersLay1[iC1][1]);
186 }
187}
ac903f1b 188
189 // Loop on layer 2 : finding theta, phi and r
190 for (Int_t iC2=0; iC2<fNClustersLay2; iC2++) {
191 Float_t x = fClustersLay2[iC2][0] - vtx[0];
192 Float_t y = fClustersLay2[iC2][1] - vtx[1];
193 Float_t z = fClustersLay2[iC2][2] - vtx[2];
ddced3c8 194
ac903f1b 195 Float_t r = TMath::Sqrt(TMath::Power(x,2) +
196 TMath::Power(y,2) +
197 TMath::Power(z,2));
198
199 fClustersLay2[iC2][0] = TMath::ACos(z/r); // Store Theta
ddced3c8 200 fClustersLay2[iC2][1] = TMath::ATan2(x,y); // Store Phi
ac903f1b 201 fClustersLay2[iC2][2] = z; // Store z
202
ddced3c8 203 // this only needs to be initialized for the fNClustersLay2 first associations
ac903f1b 204 fAssociationFlag[iC2] = kFALSE;
205 }
206
207 //###########################################################
208 // Loop on layer 1
209 for (Int_t iC1=0; iC1<fNClustersLay1; iC1++) {
210
211 // reset of variables for multiple candidates
ddced3c8 212 Int_t iC2WithBestDist = 0; // reset
3ef75756 213 Float_t distmin = 100.; // just to put a huge number!
ddced3c8 214 Float_t dPhimin = 0.; // Used for histograms only!
215 Float_t dThetamin = 0.; // Used for histograms only!
216 Float_t dZetamin = 0.; // Used for histograms only!
ac903f1b 217
218 // Loop on layer 2
219 for (Int_t iC2=0; iC2<fNClustersLay2; iC2++) {
220
221 // The following excludes double associations
222 if (!fAssociationFlag[iC2]) {
223
224 // find the difference in angles
225 Float_t dTheta = fClustersLay2[iC2][0] - fClustersLay1[iC1][0];
226 Float_t dPhi = fClustersLay2[iC2][1] - fClustersLay1[iC1][1];
227
228 // find the difference in z (between linear projection from layer 1
229 // and the actual point: Dzeta= z1/r1*r2 -z2)
ddced3c8 230 Float_t r2 = fClustersLay2[iC2][2]/TMath::Cos(fClustersLay2[iC2][0]);
231 Float_t dZeta = fClustersLay1[iC1][2]*r2 - fClustersLay2[iC2][2];
232
233 if (fHistOn) {
234 fhClustersDPhiAll->Fill(dPhi);
235 fhClustersDThetaAll->Fill(dTheta);
236 fhClustersDZetaAll->Fill(dZeta);
ac903f1b 237 fhDPhiVsDThetaAll->Fill(dTheta, dPhi);
ddced3c8 238 fhDPhiVsDZetaAll->Fill(dZeta, dPhi);
ac903f1b 239 }
240 // make "elliptical" cut in Phi and Zeta!
241 Float_t d = TMath::Sqrt(TMath::Power(dPhi/fPhiWindow,2) + TMath::Power(dZeta/fZetaWindow,2));
3ef75756 242
ac903f1b 243 if (d>1) continue;
244
ddced3c8 245 //look for the minimum distance: the minimum is in iC2WithBestDist
3ef75756 246 if (TMath::Sqrt(dZeta*dZeta+(r2*dPhi*r2*dPhi)) < distmin ) {
247 distmin=TMath::Sqrt(dZeta*dZeta + (r2*dPhi*r2*dPhi));
ddced3c8 248 dPhimin = dPhi;
249 dThetamin = dTheta;
250 dZetamin = dZeta;
251 iC2WithBestDist = iC2;
ac903f1b 252 }
253 }
254 } // end of loop over clusters in layer 2
255
3ef75756 256 if (distmin<100) { // This means that a cluster in layer 2 was found that mathes with iC1
257
258 if (fHistOn) {
259 fhClustersDPhiAcc->Fill(dPhimin);
260 fhClustersDThetaAcc->Fill(dThetamin);
261 fhClustersDZetaAcc->Fill(dZetamin);
262 fhDPhiVsDThetaAcc->Fill(dThetamin, dPhimin);
263 fhDPhiVsDZetaAcc->Fill(dZetamin, dPhimin);
264 }
ac903f1b 265
ddced3c8 266 if (fOnlyOneTrackletPerC2) fAssociationFlag[iC2WithBestDist] = kTRUE; // flag the association
ac903f1b 267
268 // store the tracklet
269
ddced3c8 270 // use the theta from the clusters in the first layer
271 fTracklets[fNTracklets][0] = fClustersLay1[iC1][0];
ac903f1b 272 // use the phi from the clusters in the first layer
273 fTracklets[fNTracklets][1] = fClustersLay1[iC1][1];
274 // Store the difference between phi1 and phi2
ddced3c8 275 fTracklets[fNTracklets][2] = fClustersLay1[iC1][1] - fClustersLay2[iC2WithBestDist][1];
276
3ef75756 277 if (fHistOn) {
278 Float_t eta=fTracklets[fNTracklets][0];
279 eta= TMath::Tan(eta/2.);
280 eta=-TMath::Log(eta);
281 fhetaTracklets->Fill(eta);
282 fhphiTracklets->Fill(fTracklets[fNTracklets][1]);
283 }
ac903f1b 284
3ef75756 285 AliDebug(1,Form(" Adding tracklet candidate %d ", fNTracklets));
286 AliDebug(1,Form(" Cl. %d of Layer 1 and %d of Layer 2", iC1,
287 iC2WithBestDist));
288 fNTracklets++;
ac903f1b 289 }
3ef75756 290
291 // Delete the following else if you do not want to save Clusters!
292
293 else { // This means that the cluster has not been associated
294
295 // store the cluster
296
297 fTracklets[fNTracklets][0] = fClustersLay1[iC1][0];
298 fTracklets[fNTracklets][1] = fClustersLay1[iC1][1];
299 // Store a flag. This will indicate that the "tracklet"
300 // was indeed a single cluster!
301 fTracklets[fNTracklets][2] = -999999.;
302 AliDebug(1,Form(" Adding a single cluster %d (cluster %d of layer 1)",
303 fNTracklets, iC1));
304 fNTracklets++;
305 }
306
ac903f1b 307 } // end of loop over clusters in layer 1
308
309 AliDebug(1,Form("%d tracklets found", fNTracklets));
310}
311
312//____________________________________________________________________
313void
314AliITSMultReconstructor::LoadClusterArrays(TTree* itsClusterTree) {
315 // This method
316 // - gets the clusters from the cluster tree
317 // - convert them into global coordinates
318 // - store them in the internal arrays
319
320 AliDebug(1,"Loading clusters ...");
321
322 fNClustersLay1 = 0;
323 fNClustersLay2 = 0;
324
b51872de 325 TClonesArray* itsClusters = new TClonesArray("AliITSRecPoint");
326 TBranch* itsClusterBranch=itsClusterTree->GetBranch("ITSRecPoints");
ddced3c8 327
ac903f1b 328 itsClusterBranch->SetAddress(&itsClusters);
ddced3c8 329
ac903f1b 330 Int_t nItsSubs = (Int_t)itsClusterTree->GetEntries();
ddced3c8 331
ac903f1b 332 // loop over the its subdetectors
333 for (Int_t iIts=0; iIts < nItsSubs; iIts++) {
334
335 if (!itsClusterTree->GetEvent(iIts))
336 continue;
337
338 Int_t nClusters = itsClusters->GetEntriesFast();
339
340 // stuff needed to get the global coordinates
341 Double_t rot[9]; fGeometry->GetRotMatrix(iIts,rot);
342 Int_t lay,lad,det; fGeometry->GetModuleId(iIts,lay,lad,det);
343 Float_t tx,ty,tz; fGeometry->GetTrans(lay,lad,det,tx,ty,tz);
344
345 // Below:
346 // "alpha" is the angle from the global X-axis to the
347 // local GEANT X'-axis ( rot[0]=cos(alpha) and rot[1]=sin(alpha) )
348 // "phi" is the angle from the global X-axis to the
349 // local cluster X"-axis
350
351 Double_t alpha = TMath::ATan2(rot[1],rot[0])+TMath::Pi();
352 Double_t itsPhi = TMath::Pi()/2+alpha;
353
354 if (lay==1) itsPhi+=TMath::Pi();
355 Double_t cp=TMath::Cos(itsPhi), sp=TMath::Sin(itsPhi);
356 Double_t r=tx*cp+ty*sp;
357
358 // loop over clusters
359 while(nClusters--) {
b51872de 360 AliITSRecPoint* cluster = (AliITSRecPoint*)itsClusters->UncheckedAt(nClusters);
ac903f1b 361
362 if (cluster->GetLayer()>1)
363 continue;
364
365 Float_t x = r*cp - cluster->GetY()*sp;
366 Float_t y = r*sp + cluster->GetY()*cp;
367 Float_t z = cluster->GetZ();
368
369 if (cluster->GetLayer()==0) {
370 fClustersLay1[fNClustersLay1][0] = x;
371 fClustersLay1[fNClustersLay1][1] = y;
372 fClustersLay1[fNClustersLay1][2] = z;
373 fNClustersLay1++;
374 }
375 if (cluster->GetLayer()==1) {
376 fClustersLay2[fNClustersLay2][0] = x;
377 fClustersLay2[fNClustersLay2][1] = y;
378 fClustersLay2[fNClustersLay2][2] = z;
379 fNClustersLay2++;
380 }
381
382 }// end of cluster loop
383 } // end of its "subdetector" loop
384
385 AliDebug(1,Form("(clusters in layer 1 : %d, layer 2: %d)",fNClustersLay1,fNClustersLay2));
386}
387//____________________________________________________________________
388void
389AliITSMultReconstructor::SaveHists() {
3ef75756 390 // This method save the histograms on the output file
391 // (only if fHistOn is TRUE).
ac903f1b 392
393 if (!fHistOn)
394 return;
395
ddced3c8 396 fhClustersDPhiAll->Write();
397 fhClustersDThetaAll->Write();
398 fhClustersDZetaAll->Write();
ac903f1b 399 fhDPhiVsDThetaAll->Write();
ddced3c8 400 fhDPhiVsDZetaAll->Write();
401
402 fhClustersDPhiAcc->Write();
403 fhClustersDThetaAcc->Write();
404 fhClustersDZetaAcc->Write();
ac903f1b 405 fhDPhiVsDThetaAcc->Write();
ddced3c8 406 fhDPhiVsDZetaAcc->Write();
407
408 fhetaTracklets->Write();
409 fhphiTracklets->Write();
410 fhetaClustersLay1->Write();
411 fhphiClustersLay1->Write();
ac903f1b 412}