ITS/AliITSClusterFinderSPD.cxx

   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 //  Cluster finder                                                       ///
  17 //  for Silicon pixels                                                    //
  18 //                                                                        //
  19 ////////////////////////////////////////////////////////////////////////////
  20
  21 #include "AliITSClusterFinderSPD.h"
  22 #include "AliITSDetTypeRec.h"
  23 #include "AliITSRawClusterSPD.h"
  24 #include "AliITSRecPoint.h"
  25 #include "AliITSdigitSPD.h"
  26 #include "AliITSsegmentationSPD.h"
  27 #include "AliLog.h"
  28
  29 //#define DEBUG
  30
  31 ClassImp(AliITSClusterFinderSPD)
  32
  33 //______________________________________________________________________
  34 AliITSClusterFinderSPD::AliITSClusterFinderSPD():AliITSClusterFinder(),
  35 fDz(0.0),
  36 fDx(0.0),
  37 fMinNCells(0){
  38     // constructor
  39 }
  40 //----------------------------------------------------------
  41 AliITSClusterFinderSPD::AliITSClusterFinderSPD(AliITSsegmentation *seg,
  42                                                AliITSresponse *res):
  43 AliITSClusterFinder(seg,res),
  44 fDz(0.0),
  45 fDx(0.0),
  46 fMinNCells(0){
  47     // constructor
  48
  49     SetDx();
  50     SetDz();
  51 }
  52 //----------------------------------------------------------
  53 AliITSClusterFinderSPD::AliITSClusterFinderSPD(AliITSsegmentation *seg,
  54                                                TClonesArray *digits,
  55                                                TClonesArray *recp):
  56 AliITSClusterFinder(seg,0),
  57 fDz(0.0),
  58 fDx(0.0),
  59 fMinNCells(0){
  60     // constructor
  61
  62     SetDigits(digits);
  63     SetClusters(recp);
  64     SetDx();
  65     SetDz();
  66 }
  67
  68 //______________________________________________________________________
  69 AliITSClusterFinderSPD::AliITSClusterFinderSPD(const AliITSClusterFinderSPD &source) : AliITSClusterFinder(source) {
  70   // Copy constructor
  71   // Copies are not allowed. The method is protected to avoid misuse.
  72   Fatal("AliITSClusterFinderSPD","Copy constructor not allowed\n");
  73 }
  74
  75 //______________________________________________________________________
  76 AliITSClusterFinderSPD& AliITSClusterFinderSPD::operator=(const AliITSClusterFinderSPD& /* source */){
  77   // Assignment operator
  78   // Assignment is not allowed. The method is protected to avoid misuse.
  79   Fatal("= operator","Assignment operator not allowed\n");
  80   return *this;
  81 }
  82 //______________________________________________________________________
  83 void AliITSClusterFinderSPD::FindRawClusters(Int_t module){
  84     // input of Cluster Finder
  85     Int_t   digitcount  = 0;
  86     Int_t   numberd     = 100000;
  87     Int_t   *digx       = new Int_t[numberd];
  88     Int_t   *digz       = new Int_t[numberd];
  89     Int_t   *digtr1     = new Int_t[numberd];
  90     Int_t   *digtr2     = new Int_t[numberd];
  91     Int_t   *digtr3     = new Int_t[numberd];
  92     Int_t   *digtr4     = new Int_t[numberd];
  93     //  output of Cluster Finder
  94     Int_t   numberc     = 10000;
  95     Double_t *xcenterl   = new Double_t[numberc];
  96     Double_t *zcenterl   = new Double_t[numberc];
  97     Double_t *errxcenter = new Double_t[numberc];
  98     Double_t *errzcenter = new Double_t[numberc];
  99     Int_t   *tr1clus    = new Int_t[numberc];
 100     Int_t   *tr2clus    = new Int_t[numberc];
 101     Int_t   *tr3clus    = new Int_t[numberc];
 102     Int_t   nclus;
 103
 104     SetModule(module);
 105     digitcount=0;
 106     Int_t ndigits = Digits()->GetEntriesFast();
 107     if (!ndigits) return;
 108
 109     AliITSdigitSPD *dig;
 110     Int_t ndig=0,i;
 111     /*
 112     AliDebug(4," ");
 113         scanf("%d",&ndig);
 114     */
 115     for(ndig=0; ndig<ndigits; ndig++) {
 116         dig= (AliITSdigitSPD*)GetDigit(ndig);
 117         digx[digitcount] = dig->GetCoord2()+1;  //starts at 1
 118         digz[digitcount] = dig->GetCoord1()+1;  //starts at 1
 119         digtr1[digitcount] = dig->GetTrack(0);
 120         digtr2[digitcount] = -3;
 121         digtr3[digitcount] = -3;
 122         AliDebug(5,Form("digtr1[%d]=%d fTracks[%d]=%d: ",
 123                         digitcount,digtr1[digitcount],0,dig->GetTrack(0)));
 124         i=1;
 125         while(digtr1[digitcount]==dig->GetTrack(i) && i<dig->GetNTracks()) i++;
 126         AliDebug(5,Form(" fTracks[%d]=%d",i,dig->GetTrack(i)));
 127         if(i<dig->GetNTracks()){
 128             digtr2[digitcount] = dig->GetTrack(i);
 129             AliDebug(5,Form("digtr2[%d]=%d: ",digitcount,digtr2[digitcount]));
 130             while((digtr1[digitcount]==dig->GetTrack(i) ||
 131                    digtr2[digitcount]==dig->GetTrack(i))&&
 132                   i<=dig->GetNTracks()) i++;
 133             if(i<dig->GetNTracks()) digtr3[digitcount] = dig->GetTrack(i);
 134             AliDebug(5,Form(" fTracks[%d]=%d digtr3[%d]=%d",
 135                             i,i<dig->GetNTracks()?dig->GetTrack(i):-1,digitcount,digtr3[digitcount]));
 136         } // end if
 137     //        if(GetDebug(4)) cout<<endl;
 138         digtr4[digitcount] = dig->GetSignal();
 139         digitcount++;
 140     } // end for ndig
 141     ClusterFinder(digitcount,digx,digz,digtr1,digtr2,digtr3,digtr4,
 142                   nclus,xcenterl,zcenterl,errxcenter,errzcenter,
 143                   tr1clus, tr2clus, tr3clus);
 144     DigitToPoint(nclus,xcenterl,zcenterl,errxcenter,errzcenter,
 145                  tr1clus, tr2clus, tr3clus);
 146     delete[] digx;
 147     delete[] digz;
 148     delete[] digtr1;
 149     delete[] digtr2;
 150     delete[] digtr3;
 151     delete[] digtr4;
 152     delete[] xcenterl;
 153     delete[] zcenterl;
 154     delete[] errxcenter;
 155     delete[] errzcenter;
 156     delete[] tr1clus;
 157     delete[] tr2clus;
 158     delete[] tr3clus;
 159 }
 160 //----------------------------------------------------------------------
 161 void AliITSClusterFinderSPD::ClusterFinder(Int_t ndigits,Int_t digx[],
 162                                            Int_t digz[],Int_t digtr1[],
 163                                            Int_t digtr2[],Int_t digtr3[],
 164                                            Int_t digtr4[],Int_t &nclus,
 165                                            Double_t xcenter[],Double_t zcenter[],
 166                                            Double_t errxcenter[],
 167                                            Double_t errzcenter[],
 168                                            Int_t tr1clus[],Int_t tr2clus[],
 169                                            Int_t tr3clus[]){
 170     // Search for clusters of fired pixels (digits). Two digits are linked
 171     // inside a cluster if they are countiguous both in row or column
 172     // direction.  Diagonal digits are not linked.
 173     // xcenter, ycenter, zcenter are the coordinates of the center
 174     // of each found cluster, calculated from the averaging the corresponding
 175     // coordinate of the center of the linked digits. The coordinates are
 176     // given in the local reference sistem.
 177     // errxcenter, errycenter, errzcenter are the errors associated to
 178     // the corresponding average.
 179     Int_t   if1, min, max, nd;
 180     Int_t   x1, z1, t1, t2, t3, t4;
 181     Int_t   ndx, ndz, ndxmin=0, ndxmax=0, ndzmin=0, ndzmax=0;
 182     Double_t dx, dz;
 183     Int_t   i,k,ipos=0;
 184     Float_t xdum, zdum;
 185     Int_t   kmax, sigmax;
 186     Double_t deltax, deltaz;
 187     Double_t ndig;
 188     Int_t   numberd = 10000;
 189     Int_t   *ifpad  = new Int_t[numberd];
 190     Int_t   *xpad   = new Int_t[numberd];
 191     Int_t   *zpad   = new Int_t[numberd];
 192     Int_t   *tr1pad = new Int_t[numberd];
 193     Int_t   *tr2pad = new Int_t[numberd];
 194     Int_t   *tr3pad = new Int_t[numberd];
 195     Int_t   *tr4pad = new Int_t[numberd];
 196     Int_t   *iclus  = new Int_t[numberd];
 197
 198     nclus=1;
 199     for (i=0; i < ndigits ; i++){
 200         ifpad[i] = -1;
 201         iclus[i] = 0;
 202     } // end for i
 203
 204     ifpad[0]=0;
 205     for (i=0; i < ndigits-1 ; i++) {
 206         if ( ifpad[i] == -1 ) {
 207             nclus++;
 208             ipos++;
 209             ifpad[i]=nclus-1;
 210         } // end if ipad[i]
 211         for (Int_t j=i+1 ; j < ndigits ; j++)  {
 212             if (ifpad[j]== -1 ) {
 213                 dx = TMath::Abs(digx[i]-digx[j]);
 214                 dz = TMath::Abs(digz[i]-digz[j]);
 215                 // if ( ( dx+dz )==1 )  //clusters are not diagonal
 216                 if(( dx+dz )==1 || (dx==1 && dz==1)){
 217                     //diagonal clusters allowed
 218                     ipos++;
 219                     ifpad[j] = ifpad[i];
 220
 221                     x1         = digx[j];
 222                     z1         = digz[j];
 223                     digx[j]    = digx[ipos];
 224                     digz[j]    = digz[ipos];
 225                     digx[ipos] = x1;
 226                     digz[ipos] = z1;
 227
 228                     t1 = digtr1[j];
 229                     t2 = digtr2[j];
 230                     t3 = digtr3[j];
 231                     t4 = digtr4[j];
 232                     digtr1[j] = digtr1[ipos];
 233                     digtr2[j] = digtr2[ipos];
 234                     digtr3[j] = digtr3[ipos];
 235                     digtr4[j] = digtr4[ipos];
 236                     digtr1[ipos] = t1;
 237                     digtr2[ipos] = t2;
 238                     digtr3[ipos] = t3;
 239                     digtr4[ipos] = t4;
 240
 241                     if1 = ifpad[j];
 242                     ifpad[j] = ifpad[ipos];
 243                     ifpad[ipos] = if1;
 244                 } // end dx+dx...
 245             }// end if ifpad[j]== -1
 246         } // end for j
 247     }//end loop on digits
 248     if ( ifpad[ndigits-1] == -1 ) {
 249         nclus++;
 250         ifpad[ndigits-1]=nclus-1;
 251     } // end if ifpad[ndigits-1] == -1
 252
 253     for (i=0 ; i < ndigits ; i++) iclus[ifpad[i]]++;
 254
 255     min=0;
 256     max=0;
 257     // loop on found clusters
 258     for (i=0 ; i < nclus ; i++){
 259         min = max;
 260         max += iclus[i];
 261         deltax = GetSeg()->Dpx(0);
 262         if (iclus[i]!=1){
 263             //cluster with more than one digit
 264             nd=iclus[i];
 265             ndig=(Double_t) nd;
 266             Int_t count=0;
 267             for (k=min;k<min+nd;k++){
 268                 xpad[count] = digx[k];
 269                 zpad[count] = digz[k];
 270
 271                 tr1pad[count] = digtr1[k];
 272                 tr2pad[count] = digtr2[k];
 273                 tr3pad[count] = digtr3[k];
 274                 tr4pad[count] = digtr4[k];
 275
 276                 count++;
 277             } // end for k
 278             ndxmin = xpad[TMath::LocMin(nd,xpad)];
 279             ndxmax = xpad[TMath::LocMax(nd,xpad)];
 280             ndzmin = zpad[TMath::LocMin(nd,zpad)];
 281             ndzmax = zpad[TMath::LocMax(nd,zpad)];
 282             ndx = ndxmax - ndxmin+1;
 283             ndz = ndzmax - ndzmin+1;
 284
 285             // calculate x and z coordinates of the center of the cluster
 286             GetSeg()->GetPadCxz(digx[min],digz[min]-1,xdum, zdum);
 287
 288             if (ndx == 1) {
 289                 xcenter[i] = xdum;
 290             }else{
 291                 xcenter[i] = 0.;
 292                 for (k=0;k<nd;k++) {
 293                     GetSeg()->GetPadCxz(xpad[k],zpad[k]-1,xdum,zdum);
 294                     xcenter[i] += (xdum / nd);
 295                 } // end for k
 296             } // end if ndx
 297
 298             if (ndz == 1) {
 299                 zcenter[i] = zdum;
 300             } else {
 301                 zcenter[i] = 0.;
 302                 for (k=0;k<nd;k++) {
 303                     GetSeg()->GetPadCxz(xpad[k],zpad[k]-1,xdum,zdum);
 304                     zcenter[i] += (zdum / nd);
 305                 } // end for k
 306             } // end if ndz
 307
 308             // error on points in x and z directions
 309
 310             if (ndx == 1) {
 311                 errxcenter[i] = deltax / TMath::Sqrt(12.);
 312             } else {
 313                 errxcenter[i] = 0.;
 314                 for (k=0;k<nd;k++){
 315                     GetSeg()->GetPadCxz(xpad[k],zpad[k]-1,xdum,zdum);
 316                     errxcenter[i] += ((xdum-xcenter[i])*(xdum-xcenter[i]))/
 317                         (nd*(nd-1));
 318                 } // end for k
 319                 errxcenter[i] = TMath::Sqrt(errxcenter[i]);
 320             } // end if ndx
 321             if (ndz == 1) {
 322                 deltaz = GetSeg()->Dpz(digz[min]);
 323                 errzcenter[i] = deltaz / TMath::Sqrt(12.);
 324             } else {
 325                 errzcenter[i] = 0.;
 326                 for (k=0;k<nd;k++){
 327                     GetSeg()->GetPadCxz(xpad[k],zpad[k]-1,xdum,zdum);
 328                     errzcenter[i] += ((zdum-zcenter[i])*(zdum-zcenter[i]))/
 329                         (nd*(nd-1));
 330                 } // end for k
 331                 errzcenter[i] = TMath::Sqrt(errzcenter[i]);
 332             } // end if ndz
 333             // take three track numbers for the cluster
 334             // choose the track numbers of the digit with higher signal
 335             kmax = 0;
 336             sigmax = 0;
 337             for (k=0;k<nd;k++){
 338                 if(tr4pad[k] > sigmax){
 339                     sigmax = tr4pad[k];
 340                     kmax   = k;
 341                 } // end if tr4pad[k]
 342             } // end for k
 343             if(sigmax != 0) {
 344                 tr1clus[i]= tr1pad[kmax];
 345                 tr2clus[i]= tr2pad[kmax];
 346                 tr3clus[i]= tr3pad[kmax];
 347             } else {
 348                 tr1clus[i]= -2;
 349                 tr2clus[i]= -2;
 350                 tr3clus[i]= -2;
 351             } // end if sigmax
 352         } else {
 353             // cluster with single digit
 354             ndig= 1.;
 355             ndx = 1;
 356             ndz = 1;
 357             GetSeg()->GetPadCxz(digx[min],digz[min]-1,xdum,zdum);
 358             xcenter[i] = xdum;
 359             zcenter[i] = zdum;
 360             tr1clus[i]=digtr1[min];
 361             tr2clus[i]=digtr2[min];
 362             tr3clus[i]=digtr3[min];
 363             deltaz = GetSeg()->Dpz(digz[min]);
 364             errxcenter[i] = deltax / TMath::Sqrt(12.);
 365             errzcenter[i] = deltaz / TMath::Sqrt(12.);
 366         } // end if iclus[i]
 367
 368         // store the cluster information to the AliITSRawCLusterSPD object
 369
 370
 371         //put the cluster center in local reference frame of the detector
 372         // and in microns
 373         xcenter[i] = xcenter[i] - GetSeg()->Dx()/2.;
 374         zcenter[i] = zcenter[i] - GetSeg()->Dz()/2.;
 375
 376         AliITSRawClusterSPD *clust = new AliITSRawClusterSPD(zcenter[i], //f
 377                                                              xcenter[i], //f
 378                                                              ndig, //f
 379                                                              ndz,ndx, //ii
 380                                                              ndxmin,ndxmax,//ii
 381                                                              (Double_t) ndzmin,
 382                                                              (Double_t) ndzmax,
 383                                                              0,GetModule());
 384         fDetTypeRec->AddCluster(0,clust);
 385         delete clust;
 386     }//end loop on clusters
 387     delete[] ifpad;
 388     delete[] xpad ;
 389     delete[] zpad ;
 390     delete[] iclus;
 391     delete[] tr1pad;
 392     delete[] tr2pad;
 393     delete[] tr3pad;
 394     delete[] tr4pad;
 395 }
 396 //______________________________________________________----------------
 397 void AliITSClusterFinderSPD::DigitToPoint(Int_t nclus,
 398                                           Double_t *xcenter,Double_t *zcenter,
 399                                           Double_t *errxcenter,
 400                                           Double_t *errzcenter,
 401                                           Int_t *tr1clus, Int_t *tr2clus,
 402                                           Int_t *tr3clus){
 403     // A point is associated to each cluster of SPD digits. The points
 404     // and their associated errors are stored in the file galiceSP.root.
 405     Double_t l[3],xg,zg;
 406     const Double_t kconv = 1.0e-4; // micron -> cm
 407
 408     // get rec points
 409     for (Int_t i=0; i<nclus; i++){
 410         l[0] = kconv*xcenter[i];
 411         l[1] = kconv*GetSeg()->Dy()/2.;
 412         l[2] = kconv*zcenter[i];
 413
 414         xg = l[0];
 415         zg = l[2];
 416
 417         Double_t sigma2x = (kconv*errxcenter[i]) * (kconv*errxcenter[i]);
 418         Double_t sigma2z = (kconv*errzcenter[i]) * (kconv*errzcenter[i]);
 419         AliITSRecPoint rnew;
 420         rnew.SetX(xg);
 421         rnew.SetZ(zg);
 422         rnew.SetQ(1.);
 423         rnew.SetdEdX(0.);
 424         rnew.SetSigmaX2(sigma2x);
 425         rnew.SetSigmaZ2(sigma2z);
 426         rnew.fTracks[0]=tr1clus[i];
 427         rnew.fTracks[1]=tr2clus[i];
 428         rnew.fTracks[2]=tr3clus[i];
 429         fDetTypeRec->AddRecPoint(rnew);
 430     } // end for i
 431 }