1 /**************************************************************************
2 * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
4 * Author: The ALICE Off-line Project. *
5 * Contributors are mentioned in the code where appropriate. *
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 **************************************************************************/
18 Revision 1.5 2001/07/20 14:32:44 kowal2
19 Processing of many events possible now
21 Revision 1.4 2001/04/17 08:06:27 hristov
22 Possibility to define the magnetic field in the reconstruction (Yu.Belikov)
24 Revision 1.3 2000/10/05 16:14:01 kowal2
27 Revision 1.2 2000/06/30 12:07:50 kowal2
28 Updated from the TPC-PreRelease branch
30 Revision 1.1.2.1 2000/06/25 08:53:55 kowal2
31 Splitted from AliTPCtracking
35 //-------------------------------------------------------
36 // Implementation of the TPC clusterer
38 // Origin: Jouri Belikov, CERN, Jouri.Belikov@cern.ch
39 //-------------------------------------------------------
41 #include "AliTPCclusterer.h"
42 #include "AliTPCcluster.h"
43 #include <TObjArray.h>
45 #include "AliTPCClustersArray.h"
46 #include "AliTPCClustersRow.h"
47 #include "AliDigits.h"
48 #include "AliSimDigits.h"
49 #include "AliTPCParam.h"
53 void AliTPCclusterer::FindPeaks(Int_t k,Int_t max,
54 AliBin *b,Int_t *idx,UInt_t *msk,Int_t& n) {
57 if (IsMaximum(k,max,b)) {
58 idx[n]=k; msk[n]=(2<<n);
62 if (b[k-max].GetMask()&1) FindPeaks(k-max,max,b,idx,msk,n);
63 if (b[k-1 ].GetMask()&1) FindPeaks(k-1 ,max,b,idx,msk,n);
64 if (b[k+max].GetMask()&1) FindPeaks(k+max,max,b,idx,msk,n);
65 if (b[k+1 ].GetMask()&1) FindPeaks(k+1 ,max,b,idx,msk,n);
68 void AliTPCclusterer::MarkPeak(Int_t k, Int_t max, AliBin *bins, UInt_t m) {
70 UShort_t q=bins[k].GetQ();
72 bins[k].SetMask(bins[k].GetMask()|m);
74 if (bins[k-max].GetQ() <= q)
75 if ((bins[k-max].GetMask()&m) == 0) MarkPeak(k-max,max,bins,m);
76 if (bins[k-1 ].GetQ() <= q)
77 if ((bins[k-1 ].GetMask()&m) == 0) MarkPeak(k-1 ,max,bins,m);
78 if (bins[k+max].GetQ() <= q)
79 if ((bins[k+max].GetMask()&m) == 0) MarkPeak(k+max,max,bins,m);
80 if (bins[k+1 ].GetQ() <= q)
81 if ((bins[k+1 ].GetMask()&m) == 0) MarkPeak(k+1 ,max,bins,m);
84 void AliTPCclusterer::MakeCluster(Int_t k,Int_t max,AliBin *bins,UInt_t m,
86 //make cluster using digits of this peak
87 Float_t q=(Float_t)bins[k].GetQ();
88 Int_t i=k/max, j=k-i*max;
93 c.SetSigmaY2(c.GetSigmaY2()+i*i*q);
94 c.SetSigmaZ2(c.GetSigmaZ2()+j*j*q);
96 bins[k].SetMask(0xFFFFFFFE);
98 if (bins[k-max].GetMask() == m) MakeCluster(k-max,max,bins,m,c);
99 if (bins[k-1 ].GetMask() == m) MakeCluster(k-1 ,max,bins,m,c);
100 if (bins[k+max].GetMask() == m) MakeCluster(k+max,max,bins,m,c);
101 if (bins[k+1 ].GetMask() == m) MakeCluster(k+1 ,max,bins,m,c);
104 //_____________________________________________________________________________
105 void AliTPCclusterer::Digits2Clusters(const AliTPCParam *par, TFile *of, Int_t eventn)
107 //-----------------------------------------------------------------
108 // This is a simple cluster finder.
109 //-----------------------------------------------------------------
110 TDirectory *savedir=gDirectory;
113 cerr<<"AliTPC::Digits2Clusters(): output file not open !\n";
117 const Int_t kMAXZ=par->GetMaxTBin()+2;
123 // for backward compatibility
125 sprintf(dname,"TreeD_75x40_100x60");
126 sprintf(cname,"TreeC_TPC");
129 sprintf(dname,"TreeD_75x40_100x60_%d",eventn);
130 sprintf(cname,"TreeC_TPC_%d",eventn);
132 TTree *t = (TTree *)gDirectory->Get(dname);
134 AliSimDigits digarr, *dummy=&digarr;
135 t->GetBranch("Segment")->SetAddress(&dummy);
136 Stat_t nentries = t->GetEntries();
140 ((AliTPCParam*)par)->Write(par->GetTitle());
141 AliTPCClustersArray carray;
143 carray.SetClusterType("AliTPCcluster");
150 for (Int_t n=0; n<nentries; n++) {
153 if (!par->AdjustSectorRow(digarr.GetID(),sec,row)) {
154 cerr<<"AliTPC warning: invalid segment ID ! "<<digarr.GetID()<<endl;
158 AliTPCClustersRow *clrow=carray.CreateRow(sec,row);
160 Float_t rx=par->GetPadRowRadii(sec,row);
164 const Int_t kNIS=par->GetNInnerSector(), kNOS=par->GetNOuterSector();
166 npads = par->GetNPadsLow(row);
167 sign = (sec < kNIS/2) ? 1 : -1;
169 npads = par->GetNPadsUp(row);
170 sign = ((sec-kNIS) < kNOS/2) ? 1 : -1;
174 const Int_t kMAXBIN=kMAXZ*(npads+2);
175 AliBin *bins=new AliBin[kMAXBIN];
176 for (Int_t ii=0;ii<kMAXBIN;ii++) {
177 bins[ii].SetQ(0); bins[ii].SetMask(0xFFFFFFFE);
182 Short_t dig=digarr.CurrentDigit();
183 if (dig<=par->GetZeroSup()) continue;
184 Int_t j=digarr.CurrentRow()+1, i=digarr.CurrentColumn()+1;
185 bins[i*kMAXZ+j].SetQ(dig);
186 bins[i*kMAXZ+j].SetMask(1);
187 } while (digarr.Next());
190 for (Int_t i=0; i<kMAXBIN; i++) {
191 if ((bins[i].GetMask()&1) == 0) continue;
192 Int_t idx[32]; UInt_t msk[32]; Int_t npeaks=0;
193 FindPeaks(i, kMAXZ, bins, idx, msk, npeaks);
195 if (npeaks>30) continue;
198 for (k=0; k<npeaks-1; k++){//mark adjacent peaks
199 if (idx[k] < 0) continue; //this peak is already removed
200 for (l=k+1; l<npeaks; l++) {
201 if (idx[l] < 0) continue; //this peak is already removed
202 Int_t ki=idx[k]/kMAXZ, kj=idx[k] - ki*kMAXZ;
203 Int_t li=idx[l]/kMAXZ, lj=idx[l] - li*kMAXZ;
204 Int_t di=TMath::Abs(ki - li);
205 Int_t dj=TMath::Abs(kj - lj);
206 if (di>1 || dj>1) continue;
207 if (bins[idx[k]].GetQ() > bins[idx[l]].GetQ()) {
218 for (k=0; k<npeaks; k++) {
219 MarkPeak(TMath::Abs(idx[k]), kMAXZ, bins, msk[k]);
222 for (k=0; k<npeaks; k++) {
223 if (idx[k] < 0) continue; //removed peak
225 MakeCluster(idx[k], kMAXZ, bins, msk[k], c);
226 if (c.GetQ() < 5) continue; //noise cluster
227 c.SetY(c.GetY()/c.GetQ());
228 c.SetZ(c.GetZ()/c.GetQ());
230 Float_t s2 = c.GetSigmaY2()/c.GetQ() - c.GetY()*c.GetY();
231 Float_t w=par->GetPadPitchWidth(sec);
232 c.SetSigmaY2((s2 + 1./12.)*w*w);
234 c.SetSigmaY2(c.GetSigmaY2()*0.108);
235 if (sec<par->GetNInnerSector()) c.SetSigmaY2(c.GetSigmaY2()*2.07);
238 s2 = c.GetSigmaZ2()/c.GetQ() - c.GetZ()*c.GetZ();
240 c.SetSigmaZ2((s2 + 1./12.)*w*w);
242 c.SetSigmaZ2(c.GetSigmaZ2()*0.169);
243 if (sec<par->GetNInnerSector()) c.SetSigmaZ2(c.GetSigmaZ2()*1.77);
246 c.SetY((c.GetY() - 0.5 - 0.5*npads)*par->GetPadPitchWidth(sec));
247 c.SetZ(par->GetZWidth()*(c.GetZ()-1));
248 c.SetZ(c.GetZ() - 3.*par->GetZSigma()); // PASA delay
249 c.SetZ(sign*(par->GetZLength() - c.GetZ()));
251 if (rx<230./250.*TMath::Abs(c.GetZ())) continue;
253 Int_t ki=idx[k]/kMAXZ, kj=idx[k] - ki*kMAXZ;
254 c.SetLabel(digarr.GetTrackID(kj-1,ki-1,0),0);
255 c.SetLabel(digarr.GetTrackID(kj-1,ki-1,1),1);
256 c.SetLabel(digarr.GetTrackID(kj-1,ki-1,2),2);
258 c.SetQ(bins[idx[k]].GetQ());
260 if (ki==1 || ki==npads || kj==1 || kj==kMAXZ-2) {
261 c.SetSigmaY2(c.GetSigmaY2()*25.);
262 c.SetSigmaZ2(c.GetSigmaZ2()*4.);
264 clrow->InsertCluster(&c); ncl++;
267 carray.StoreRow(sec,row);
268 carray.ClearRow(sec,row);
270 //cerr<<"sector, row, compressed digits, clusters: "
271 //<<sec<<' '<<row<<' '<<digarr.GetSize()<<' '<<ncl<<" \r";
278 cerr<<"Number of found clusters : "<<nclusters<<" \n";
280 carray.GetTree()->SetName(cname);
281 carray.GetTree()->Write();