ITS/AliITSClusterFinderSDD.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 #include <iostream.h>
  16 #include <TFile.h>
  17 #include <TMath.h>
  18 #include <math.h>
  19
  20 #include "AliITSClusterFinderSDD.h"
  21 #include "AliITSMapA1.h"
  22 #include "AliITS.h"
  23 #include "AliITSdigit.h"
  24 #include "AliITSRawCluster.h"
  25 #include "AliITSRecPoint.h"
  26 #include "AliITSsegmentation.h"
  27 #include "AliITSresponseSDD.h"
  28 #include "AliRun.h"
  29
  30 ClassImp(AliITSClusterFinderSDD)
  31
  32 //______________________________________________________________________
  33 AliITSClusterFinderSDD::AliITSClusterFinderSDD(AliITSsegmentation *seg,
  34                                                AliITSresponse *response,
  35                                                TClonesArray *digits,
  36                                                TClonesArray *recp){
  37     // standard constructor
  38
  39     fSegmentation=seg;
  40     fResponse=response;
  41     fDigits=digits;
  42     fClusters=recp;
  43     fNclusters= fClusters->GetEntriesFast();
  44     SetCutAmplitude();
  45     SetDAnode();
  46     SetDTime();
  47     SetMinPeak();
  48     SetMinNCells();
  49     SetMaxNCells();
  50     SetTimeCorr();
  51     SetMinCharge();
  52     fMap=new AliITSMapA1(fSegmentation,fDigits,fCutAmplitude);
  53 }
  54 //______________________________________________________________________
  55 AliITSClusterFinderSDD::AliITSClusterFinderSDD(){
  56     // default constructor
  57
  58     fSegmentation=0;
  59     fResponse=0;
  60     fDigits=0;
  61     fClusters=0;
  62     fNclusters=0;
  63     fMap=0;
  64     fCutAmplitude=0;
  65     SetDAnode();
  66     SetDTime();
  67     SetMinPeak();
  68     SetMinNCells();
  69     SetMaxNCells();
  70     SetTimeCorr();
  71     SetMinCharge();
  72 }
  73 //____________________________________________________________________________
  74 AliITSClusterFinderSDD::~AliITSClusterFinderSDD(){
  75     // destructor
  76
  77     if(fMap) delete fMap;
  78 }
  79 //______________________________________________________________________
  80 void AliITSClusterFinderSDD::SetCutAmplitude(Float_t nsigma){
  81     // set the signal threshold for cluster finder
  82     Float_t baseline,noise,noise_after_el;
  83
  84     fResponse->GetNoiseParam(noise,baseline);
  85     noise_after_el = ((AliITSresponseSDD*)fResponse)->GetNoiseAfterElectronics();
  86     fCutAmplitude=(Int_t)((baseline + nsigma*noise_after_el));
  87 }
  88 //______________________________________________________________________
  89 void AliITSClusterFinderSDD::Find1DClusters(){
  90     // find 1D clusters
  91     static AliITS *iTS=(AliITS*)gAlice->GetModule("ITS");
  92
  93     // retrieve the parameters
  94     Int_t fNofMaps = fSegmentation->Npz();
  95     Int_t fMaxNofSamples = fSegmentation->Npx();
  96     Int_t fNofAnodes = fNofMaps/2;
  97     Int_t dummy=0;
  98     Float_t fTimeStep = fSegmentation->Dpx(dummy);
  99     Float_t fSddLength = fSegmentation->Dx();
 100     Float_t fDriftSpeed = fResponse->DriftSpeed();
 101     Float_t anodePitch = fSegmentation->Dpz(dummy);
 102
 103     // map the signal
 104     fMap->SetThreshold(fCutAmplitude);
 105     fMap->FillMap();
 106
 107     Float_t noise;
 108     Float_t baseline;
 109     fResponse->GetNoiseParam(noise,baseline);
 110
 111     Int_t nofFoundClusters = 0;
 112     Int_t i;
 113     Float_t **dfadc = new Float_t*[fNofAnodes];
 114     for(i=0;i<fNofAnodes;i++) dfadc[i] = new Float_t[fMaxNofSamples];
 115     Float_t fadc = 0.;
 116     Float_t fadc1 = 0.;
 117     Float_t fadc2 = 0.;
 118     Int_t j,k,idx,l,m;
 119     for(j=0;j<2;j++) {
 120         for(k=0;k<fNofAnodes;k++) {
 121             idx = j*fNofAnodes+k;
 122             // signal (fadc) & derivative (dfadc)
 123             dfadc[k][255]=0.;
 124             for(l=0; l<fMaxNofSamples; l++) {
 125                 fadc2=(Float_t)fMap->GetSignal(idx,l);
 126                 if(l>0) fadc1=(Float_t)fMap->GetSignal(idx,l-1);
 127                 if(l>0) dfadc[k][l-1] = fadc2-fadc1;
 128             } // samples
 129         } // anodes
 130
 131         for(k=0;k<fNofAnodes;k++) {
 132         //cout << "Anode: " << k+1 << ", Wing: " << j+1 << endl;
 133             idx = j*fNofAnodes+k;
 134             Int_t imax = 0;
 135             Int_t imaxd = 0;
 136             Int_t it=0;
 137             while(it <= fMaxNofSamples-3) {
 138                 imax = it;
 139                 imaxd = it;
 140                 // maximum of signal
 141                 Float_t fadcmax = 0.;
 142                 Float_t dfadcmax = 0.;
 143                 Int_t lthrmina = 1;
 144                 Int_t lthrmint = 3;
 145                 Int_t lthra = 1;
 146                 Int_t lthrt = 0;
 147                 for(m=0;m<20;m++) {
 148                     Int_t id = it+m;
 149                     if(id>=fMaxNofSamples) break;
 150                     fadc=(float)fMap->GetSignal(idx,id);
 151                     if(fadc > fadcmax) { fadcmax = fadc; imax = id;}
 152                     if(fadc > (float)fCutAmplitude) {
 153                         lthrt++;
 154                     } // end if
 155                     if(dfadc[k][id] > dfadcmax) {
 156                         dfadcmax = dfadc[k][id];
 157                         imaxd = id;
 158                     } // end if
 159                 } // end for m
 160                 it = imaxd;
 161                 if(fMap->TestHit(idx,imax) == kEmpty) {it++; continue;}
 162                 // cluster charge
 163                 Int_t tstart = it-2;
 164                 if(tstart < 0) tstart = 0;
 165                 Bool_t ilcl = 0;
 166                 if(lthrt >= lthrmint && lthra >= lthrmina) ilcl = 1;
 167                 if(ilcl) {
 168                     nofFoundClusters++;
 169                     Int_t tstop = tstart;
 170                     Float_t dfadcmin = 10000.;
 171                     Int_t ij;
 172                     for(ij=0; ij<20; ij++) {
 173                         if(tstart+ij > 255) { tstop = 255; break; }
 174                         fadc=(float)fMap->GetSignal(idx,tstart+ij);
 175                         if((dfadc[k][tstart+ij] < dfadcmin) &&
 176                            (fadc > fCutAmplitude)) {
 177                             tstop = tstart+ij+5;
 178                             if(tstop > 255) tstop = 255;
 179                             dfadcmin = dfadc[k][it+ij];
 180                         } // end if
 181                     } // end for ij
 182
 183                     Float_t clusterCharge = 0.;
 184                     Float_t clusterAnode = k+0.5;
 185                     Float_t clusterTime = 0.;
 186                     Float_t clusterMult = 0.;
 187                     Float_t clusterPeakAmplitude = 0.;
 188                     Int_t its,peakpos=-1;
 189                     Float_t n, baseline;
 190                     fResponse->GetNoiseParam(n,baseline);
 191                     for(its=tstart; its<=tstop; its++) {
 192                         fadc=(float)fMap->GetSignal(idx,its);
 193                         if(fadc>baseline) fadc-=baseline;
 194                         else fadc=0.;
 195                         clusterCharge += fadc;
 196                         // as a matter of fact we should take the peak
 197                         // pos before FFT
 198                         // to get the list of tracks !!!
 199                         if(fadc > clusterPeakAmplitude) {
 200                             clusterPeakAmplitude = fadc;
 201                             //peakpos=fMap->GetHitIndex(idx,its);
 202                             Int_t shift=(int)(fTimeCorr/fTimeStep);
 203                             if(its>shift && its<(fMaxNofSamples-shift))
 204                                 peakpos=fMap->GetHitIndex(idx,its+shift);
 205                             else peakpos=fMap->GetHitIndex(idx,its);
 206                             if(peakpos<0) peakpos=fMap->GetHitIndex(idx,its);
 207                         } // end if
 208                         clusterTime += fadc*its;
 209                         if(fadc > 0) clusterMult++;
 210                         if(its == tstop) {
 211                             clusterTime /= (clusterCharge/fTimeStep);   // ns
 212                             if(clusterTime>fTimeCorr) clusterTime-=fTimeCorr;
 213                             //ns
 214                         } // end if
 215                     } // end for its
 216
 217                     Float_t clusteranodePath = (clusterAnode - fNofAnodes/2)*
 218                                                                     anodePitch;
 219                     Float_t clusterDriftPath = clusterTime*fDriftSpeed;
 220                     clusterDriftPath = fSddLength-clusterDriftPath;
 221                     if(clusterCharge <= 0.) break;
 222                     AliITSRawClusterSDD clust(j+1,clusterAnode,clusterTime,
 223                                               clusterCharge,
 224                                               clusterPeakAmplitude,
 225                                               peakpos,0.,0.,clusterDriftPath,
 226                                               clusteranodePath,clusterMult,0,0,
 227                                               0,0,0,0,0);
 228                     iTS->AddCluster(1,&clust);
 229                     it = tstop;
 230                 } // ilcl
 231                 it++;
 232             } // while (samples)
 233         } // anodes
 234     } // detectors (2)
 235     //fMap->ClearMap();
 236
 237     for(i=0;i<fNofAnodes;i++) delete[] dfadc[i];
 238     delete [] dfadc;
 239
 240     return;
 241 }
 242 //______________________________________________________________________
 243 void AliITSClusterFinderSDD::Find1DClustersE(){
 244     // find 1D clusters
 245     static AliITS *iTS=(AliITS*)gAlice->GetModule("ITS");
 246     // retrieve the parameters
 247     Int_t fNofMaps = fSegmentation->Npz();
 248     Int_t fMaxNofSamples = fSegmentation->Npx();
 249     Int_t fNofAnodes = fNofMaps/2;
 250     Int_t dummy=0;
 251     Float_t fTimeStep = fSegmentation->Dpx( dummy );
 252     Float_t fSddLength = fSegmentation->Dx();
 253     Float_t fDriftSpeed = fResponse->DriftSpeed();
 254     Float_t anodePitch = fSegmentation->Dpz( dummy );
 255     Float_t n, baseline;
 256     fResponse->GetNoiseParam( n, baseline );
 257     // map the signal
 258     fMap->SetThreshold( fCutAmplitude );
 259     fMap->FillMap();
 260     Int_t nClu = 0;
 261     //  cout << "Search  cluster... "<< endl;
 262     for( Int_t j=0; j<2; j++ ){
 263         for( Int_t k=0; k<fNofAnodes; k++ ){
 264             Int_t idx = j*fNofAnodes+k;
 265             Bool_t on = kFALSE;
 266             Int_t start = 0;
 267             Int_t nTsteps = 0;
 268             Float_t fmax = 0.;
 269             Int_t lmax = 0;
 270             Float_t charge = 0.;
 271             Float_t time = 0.;
 272             Float_t anode = k+0.5;
 273             Int_t peakpos = -1;
 274             for( Int_t l=0; l<fMaxNofSamples; l++ ){
 275                 Float_t fadc = (Float_t)fMap->GetSignal( idx, l );
 276                 if( fadc > 0.0 ){
 277                     if( on == kFALSE && l<fMaxNofSamples-4){
 278                         // star RawCluster (reset var.)
 279                         Float_t fadc1 = (Float_t)fMap->GetSignal( idx, l+1 );
 280                         if( fadc1 < fadc ) continue;
 281                         start = l;
 282                         fmax = 0.;
 283                         lmax = 0;
 284                         time = 0.;
 285                         charge = 0.;
 286                         on = kTRUE;
 287                         nTsteps = 0;
 288                     } // end if on...
 289                     nTsteps++ ;
 290                     if( fadc > baseline ) fadc -= baseline;
 291                     else fadc=0.;
 292                     charge += fadc;
 293                     time += fadc*l;
 294                     if( fadc > fmax ){
 295                         fmax = fadc;
 296                         lmax = l;
 297                         Int_t shift = (Int_t)(fTimeCorr/fTimeStep + 0.5);
 298                         if( l > shift && l < (fMaxNofSamples-shift) )
 299                             peakpos = fMap->GetHitIndex( idx, l+shift );
 300                         else
 301                             peakpos = fMap->GetHitIndex( idx, l );
 302                         if( peakpos < 0) peakpos = fMap->GetHitIndex( idx, l );
 303                     } // end if fadc
 304                 }else{ // end fadc>0
 305                     if( on == kTRUE ){
 306                         if( nTsteps > 2 ){
 307                             //  min # of timesteps for a RawCluster
 308                             // Found a RawCluster...
 309                             Int_t stop = l-1;
 310                             time /= (charge/fTimeStep);   // ns
 311                                 // time = lmax*fTimeStep;   // ns
 312                             if( time > fTimeCorr ) time -= fTimeCorr;   // ns
 313                             Float_t anodePath = (anode - fNofAnodes/2)*anodePitch;
 314                             Float_t driftPath = time*fDriftSpeed;
 315                             driftPath = fSddLength-driftPath;
 316                             AliITSRawClusterSDD clust(j+1,anode,time,charge,
 317                                                       fmax, peakpos,0.,0.,
 318                                                       driftPath,anodePath,
 319                                                       nTsteps,start,stop,
 320                                                       start, stop, 1, k, k );
 321                             iTS->AddCluster( 1, &clust );
 322                             //  clust.PrintInfo();
 323                             nClu++;
 324                         } // end if nTsteps
 325                         on = kFALSE;
 326                     } // end if on==kTRUE
 327                 } // end if fadc>0
 328             } // samples
 329         } // anodes
 330     } // wings
 331     //  cout << "# Rawclusters " << nClu << endl;
 332     return;
 333 }
 334 //_______________________________________________________________________
 335 Int_t AliITSClusterFinderSDD::SearchPeak(Float_t *spect,Int_t xdim,Int_t zdim,
 336                                          Int_t *peakX, Int_t *peakZ,
 337                                          Float_t *peakAmp, Float_t minpeak ){
 338     // search peaks on a 2D cluster
 339     Int_t npeak = 0;    // # peaks
 340     Int_t i,j;
 341     // search peaks
 342     for( Int_t z=1; z<zdim-1; z++ ){
 343         for( Int_t x=2; x<xdim-3; x++ ){
 344             Float_t sxz = spect[x*zdim+z];
 345             Float_t sxz1 = spect[(x+1)*zdim+z];
 346             Float_t sxz2 = spect[(x-1)*zdim+z];
 347             // search a local max. in s[x,z]
 348             if( sxz < minpeak || sxz1 <= 0 || sxz2 <= 0 ) continue;
 349             if( sxz >= spect[(x+1)*zdim+z  ] && sxz >= spect[(x-1)*zdim+z  ] &&
 350                 sxz >= spect[x*zdim    +z+1] && sxz >= spect[x*zdim    +z-1] &&
 351                 sxz >= spect[(x+1)*zdim+z+1] && sxz >= spect[(x+1)*zdim+z-1] &&
 352                 sxz >= spect[(x-1)*zdim+z+1] && sxz >= spect[(x-1)*zdim+z-1] ){
 353                 // peak found
 354                 peakX[npeak] = x;
 355                 peakZ[npeak] = z;
 356                 peakAmp[npeak] = sxz;
 357                 npeak++;
 358             } // end if ....
 359         } // end for x
 360     } // end for z
 361     // search groups of peaks with same amplitude.
 362     Int_t *flag = new Int_t[npeak];
 363     for( i=0; i<npeak; i++ ) flag[i] = 0;
 364     for( i=0; i<npeak; i++ ){
 365         for( j=0; j<npeak; j++ ){
 366             if( i==j) continue;
 367             if( flag[j] > 0 ) continue;
 368             if( peakAmp[i] == peakAmp[j] &&
 369                 TMath::Abs(peakX[i]-peakX[j])<=1 &&
 370                 TMath::Abs(peakZ[i]-peakZ[j])<=1 ){
 371                 if( flag[i] == 0) flag[i] = i+1;
 372                 flag[j] = flag[i];
 373             } // end if ...
 374         } // end for j
 375     } // end for i
 376     // make average of peak groups
 377     for( i=0; i<npeak; i++ ){
 378         Int_t nFlag = 1;
 379         if( flag[i] <= 0 ) continue;
 380         for( j=0; j<npeak; j++ ){
 381             if( i==j ) continue;
 382             if( flag[j] != flag[i] ) continue;
 383             peakX[i] += peakX[j];
 384             peakZ[i] += peakZ[j];
 385             nFlag++;
 386             npeak--;
 387             for( Int_t k=j; k<npeak; k++ ){
 388                 peakX[k] = peakX[k+1];
 389                 peakZ[k] = peakZ[k+1];
 390                 peakAmp[k] = peakAmp[k+1];
 391                 flag[k] = flag[k+1];
 392             } // end for k
 393             j--;
 394         } // end for j
 395         if( nFlag > 1 ){
 396             peakX[i] /= nFlag;
 397             peakZ[i] /= nFlag;
 398         } // end fi nFlag
 399     } // end for i
 400     delete [] flag;
 401     return( npeak );
 402 }
 403 //______________________________________________________________________
 404 void AliITSClusterFinderSDD::PeakFunc( Int_t xdim, Int_t zdim, Float_t *par,
 405                                        Float_t *spe, Float_t *integral){
 406     // function used to fit the clusters
 407     // par -> paramiters..
 408     // par[0]  number of peaks.
 409     // for each peak i=1, ..., par[0]
 410     //          par[i] = Ampl.
 411     //          par[i+1] = xpos
 412     //          par[i+2] = zpos
 413     //          par[i+3] = tau
 414     //          par[i+4] = sigma.
 415     Int_t electronics = fResponse->Electronics(); // 1 = PASCAL, 2 = OLA
 416     const Int_t knParam = 5;
 417     Int_t npeak = (Int_t)par[0];
 418
 419     memset( spe, 0, sizeof( Float_t )*zdim*xdim );
 420
 421     Int_t k = 1;
 422     for( Int_t i=0; i<npeak; i++ ){
 423         if( integral != 0 ) integral[i] = 0.;
 424         Float_t sigmaA2 = par[k+4]*par[k+4]*2.;
 425         Float_t T2 = par[k+3];   // PASCAL
 426         if( electronics == 2 ) { T2 *= T2; T2 *= 2; } // OLA
 427         for( Int_t z=0; z<zdim; z++ ){
 428             for( Int_t x=0; x<xdim; x++ ){
 429                 Float_t z2 = (z-par[k+2])*(z-par[k+2])/sigmaA2;
 430                 Float_t x2 = 0.;
 431                 Float_t signal = 0.;
 432                 if( electronics == 1 ){ // PASCAL
 433                     x2 = (x-par[k+1]+T2)/T2;
 434                     signal = (x2>0.) ? par[k]*x2*exp(-x2+1.-z2) :0.0; // RCCR2
 435                 //  signal =(x2>0.) ? par[k]*x2*x2*exp(-2*x2+2.-z2 ):0.0;//RCCR
 436                 }else if( electronics == 2 ) { // OLA
 437                     x2 = (x-par[k+1])*(x-par[k+1])/T2;
 438                     signal = par[k]  * exp( -x2 - z2 );
 439                 } else {
 440                     cout << "Wrong SDD Electronics =" << electronics << endl;
 441                     // exit( 1 );
 442                 } // end if electronicx
 443                 spe[x*zdim+z] += signal;
 444                 if( integral != 0 ) integral[i] += signal;
 445             } // end for x
 446         } // end for z
 447         k += knParam;
 448     } // end for i
 449     return;
 450 }
 451 //__________________________________________________________________________
 452 Float_t AliITSClusterFinderSDD::ChiSqr( Int_t xdim, Int_t zdim, Float_t *spe,
 453                                         Float_t *speFit ){
 454     // EVALUATES UNNORMALIZED CHI-SQUARED
 455     Float_t chi2 = 0.;
 456     for( Int_t z=0; z<zdim; z++ ){
 457         for( Int_t x=1; x<xdim-1; x++ ){
 458             Int_t index = x*zdim+z;
 459             Float_t tmp = spe[index] - speFit[index];
 460             chi2 += tmp*tmp;
 461         } // end for x
 462     } // end for z
 463     return( chi2 );
 464 }
 465 //_______________________________________________________________________
 466 void AliITSClusterFinderSDD::Minim( Int_t xdim, Int_t zdim, Float_t *param,
 467                                     Float_t *prm0,Float_t *steprm,
 468                                     Float_t *chisqr,Float_t *spe,
 469                                     Float_t *speFit ){
 470     //
 471     Int_t   k, nnn, mmm, i;
 472     Float_t p1, delta, d1, chisq1, p2, chisq2, t, p3, chisq3, a, b, p0, chisqt;
 473     const Int_t knParam = 5;
 474     Int_t npeak = (Int_t)param[0];
 475     for( k=1; k<(npeak*knParam+1); k++ ) prm0[k] = param[k];
 476     for( k=1; k<(npeak*knParam+1); k++ ){
 477         p1 = param[k];
 478         delta = steprm[k];
 479         d1 = delta;
 480         // ENSURE THAT STEP SIZE IS SENSIBLY LARGER THAN MACHINE ROUND OFF
 481         if( fabs( p1 ) > 1.0E-6 )
 482             if ( fabs( delta/p1 ) < 1.0E-4 ) delta = p1/1000;
 483             else  delta = (Float_t)1.0E-4;
 484         //  EVALUATE CHI-SQUARED AT FIRST TWO SEARCH POINTS
 485         PeakFunc( xdim, zdim, param, speFit );
 486         chisq1 = ChiSqr( xdim, zdim, spe, speFit );
 487         p2 = p1+delta;
 488         param[k] = p2;
 489         PeakFunc( xdim, zdim, param, speFit );
 490         chisq2 = ChiSqr( xdim, zdim, spe, speFit );
 491         if( chisq1 < chisq2 ){
 492             // REVERSE DIRECTION OF SEARCH IF CHI-SQUARED IS INCREASING
 493             delta = -delta;
 494             t = p1;
 495             p1 = p2;
 496             p2 = t;
 497             t = chisq1;
 498             chisq1 = chisq2;
 499             chisq2 = t;
 500         } // end if
 501         i = 1; nnn = 0;
 502         do {   // INCREMENT param(K) UNTIL CHI-SQUARED STARTS TO INCREASE
 503             nnn++;
 504             p3 = p2 + delta;
 505             mmm = nnn - (nnn/5)*5;  // multiplo de 5
 506             if( mmm == 0 ){
 507                 d1 = delta;
 508                 // INCREASE STEP SIZE IF STEPPING TOWARDS MINIMUM IS TOO SLOW
 509                 delta *= 5;
 510             } // end if
 511             param[k] = p3;
 512             // Constrain paramiters
 513             Int_t kpos = (k-1) % knParam;
 514             switch( kpos ){
 515             case 0 :
 516                 if( param[k] <= 20 ) param[k] = fMinPeak;
 517             case 1 :
 518                 if( fabs( param[k] - prm0[k] ) > 1.5 ) param[k] = prm0[k];
 519             case 2 :
 520                 if( fabs( param[k] - prm0[k] ) > 1. ) param[k] = prm0[k];
 521             case 3 :
 522                 if( param[k] < .5 ) param[k] = .5;
 523             case 4 :
 524                 if( param[k] < .288 ) param[k] = .288;  // 1/sqrt(12) = 0.288
 525             }; // end switch
 526             PeakFunc( xdim, zdim, param, speFit );
 527             chisq3 = ChiSqr( xdim, zdim, spe, speFit );
 528             if( chisq3 < chisq2 && nnn < 50 ){
 529                 p1 = p2;
 530                 p2 = p3;
 531                 chisq1 = chisq2;
 532                 chisq2 = chisq3;
 533             }else i=0;
 534         } while( i );
 535         // FIND MINIMUM OF PARABOLA DEFINED BY LAST THREE POINTS
 536         a = chisq1*(p2-p3)+chisq2*(p3-p1)+chisq3*(p1-p2);
 537         b = chisq1*(p2*p2-p3*p3)+chisq2*(p3*p3-p1*p1)+chisq3*(p1*p1-p2*p2);
 538         if( a!=0 ) p0 = (Float_t)(0.5*b/a);
 539         else p0 = 10000;
 540         //--IN CASE OF NEARLY EQUAL CHI-SQUARED AND TOO SMALL STEP SIZE PREVENT
 541         //   ERRONEOUS EVALUATION OF PARABOLA MINIMUM
 542         //---NEXT TWO LINES CAN BE OMITTED FOR HIGHER PRECISION MACHINES
 543         //dp = (Float_t) max (fabs(p3-p2), fabs(p2-p1));
 544         //if( fabs( p2-p0 ) > dp ) p0 = p2;
 545         param[k] = p0;
 546         // Constrain paramiters
 547         Int_t kpos = (k-1) % knParam;
 548         switch( kpos ){
 549         case 0 :
 550             if( param[k] <= 20 ) param[k] = fMinPeak;
 551         case 1 :
 552             if( fabs( param[k] - prm0[k] ) > 1.5 ) param[k] = prm0[k];
 553         case 2 :
 554             if( fabs( param[k] - prm0[k] ) > 1. ) param[k] = prm0[k];
 555         case 3 :
 556             if( param[k] < .5 ) param[k] = .5;
 557         case 4 :
 558             if( param[k] < .288 ) param[k] = .288;  // 1/sqrt(12) = 0.288
 559         }; // end switch
 560         PeakFunc( xdim, zdim, param, speFit );
 561         chisqt = ChiSqr( xdim, zdim, spe, speFit );
 562         // DO NOT ALLOW ERRONEOUS INTERPOLATION
 563         if( chisqt <= *chisqr ) *chisqr = chisqt;
 564         else param[k] = prm0[k];
 565         // OPTIMIZE SEARCH STEP FOR EVENTUAL NEXT CALL OF MINIM
 566         steprm[k] = (param[k]-prm0[k])/5;
 567         if( steprm[k] >= d1 ) steprm[k] = d1/5;
 568     } // end for k
 569     // EVALUATE FIT AND CHI-SQUARED FOR OPTIMIZED PARAMETERS
 570     PeakFunc( xdim, zdim, param, speFit );
 571     *chisqr = ChiSqr( xdim, zdim, spe, speFit );
 572     return;
 573 }
 574 //_________________________________________________________________________
 575 Int_t AliITSClusterFinderSDD::NoLinearFit( Int_t xdim, Int_t zdim,
 576                                            Float_t *param, Float_t *spe,
 577                                            Int_t *niter, Float_t *chir ){
 578     // fit method from Comput. Phys. Commun 46(1987) 149
 579     const Float_t kchilmt = 0.01;  //   relative accuracy
 580     const Int_t   knel = 3;        //   for parabolic minimization
 581     const Int_t   knstop = 50;     //   Max. iteration number
 582     const Int_t   knParam = 5;
 583     Int_t npeak = (Int_t)param[0];
 584     // RETURN IF NUMBER OF DEGREES OF FREEDOM IS NOT POSITIVE
 585     if( (xdim*zdim - npeak*knParam) <= 0 ) return( -1 );
 586     Float_t degFree = (xdim*zdim - npeak*knParam)-1;
 587     Int_t   n, k, iterNum = 0;
 588     Float_t *prm0 = new Float_t[npeak*knParam+1];
 589     Float_t *step = new Float_t[npeak*knParam+1];
 590     Float_t *schi = new Float_t[npeak*knParam+1];
 591     Float_t *sprm[3];
 592     sprm[0] = new Float_t[npeak*knParam+1];
 593     sprm[1] = new Float_t[npeak*knParam+1];
 594     sprm[2] = new Float_t[npeak*knParam+1];
 595     Float_t  chi0, chi1, reldif, a, b, prmin, dp;
 596     Float_t *speFit = new Float_t[ xdim*zdim ];
 597     PeakFunc( xdim, zdim, param, speFit );
 598     chi0 = ChiSqr( xdim, zdim, spe, speFit );
 599     chi1 = chi0;
 600     for( k=1; k<(npeak*knParam+1); k++) prm0[k] = param[k];
 601     for( k=1 ; k<(npeak*knParam+1); k+=knParam ){
 602         step[k] = param[k] / 20.0 ;
 603         step[k+1] = param[k+1] / 50.0;
 604         step[k+2] = param[k+2] / 50.0;
 605         step[k+3] = param[k+3] / 20.0;
 606         step[k+4] = param[k+4] / 20.0;
 607     } // end for k
 608     Int_t out = 0;
 609     do{
 610         iterNum++;
 611         chi0 = chi1;
 612         Minim( xdim, zdim, param, prm0, step, &chi1, spe, speFit );
 613         reldif = ( chi1 > 0 ) ? ((Float_t) fabs( chi1-chi0)/chi1 ) : 0;
 614         // EXIT conditions
 615         if( reldif < (float) kchilmt ){
 616             *chir  = (chi1>0) ? (float) TMath::Sqrt (chi1/degFree) :0;
 617             *niter = iterNum;
 618             out = 0;
 619             break;
 620         } // end if
 621         if( (reldif < (float)(5*kchilmt)) && (iterNum > knstop) ){
 622             *chir = (chi1>0) ?(float) TMath::Sqrt (chi1/degFree):0;
 623             *niter = iterNum;
 624             out = 0;
 625             break;
 626         } // end if
 627         if( iterNum > 5*knstop ){
 628             *chir  = (chi1>0) ?(float) TMath::Sqrt (chi1/degFree):0;
 629             *niter = iterNum;
 630             out = 1;
 631             break;
 632         } // end if
 633         if( iterNum <= knel ) continue;
 634         n = iterNum - (iterNum/knel)*knel; // EXTRAPOLATION LIMIT COUNTER N
 635         if( n > 3 || n == 0 ) continue;
 636         schi[n-1] = chi1;
 637         for( k=1; k<(npeak*knParam+1); k++ ) sprm[n-1][k] = param[k];
 638         if( n != 3 ) continue;
 639         // -EVALUATE EXTRAPOLATED VALUE OF EACH PARAMETER BY FINDING MINIMUM OF
 640         //    PARABOLA DEFINED BY LAST THREE CALLS OF MINIM
 641         for( k=1; k<(npeak*knParam+1); k++ ){
 642             Float_t tmp0 = sprm[0][k];
 643             Float_t tmp1 = sprm[1][k];
 644             Float_t tmp2 = sprm[2][k];
 645             a  = schi[0]*(tmp1-tmp2) + schi[1]*(tmp2-tmp0);
 646             a += (schi[2]*(tmp0-tmp1));
 647             b  = schi[0]*(tmp1*tmp1-tmp2*tmp2);
 648             b += (schi[1]*(tmp2*tmp2-tmp0*tmp0)+(schi[2]*
 649                                                  (tmp0*tmp0-tmp1*tmp1)));
 650             if ((double)a < 1.0E-6) prmin = 0;
 651             else prmin = (float) (0.5*b/a);
 652             dp = 5*(tmp2-tmp0);
 653             if (fabs(prmin-tmp2) > fabs(dp)) prmin = tmp2+dp;
 654             param[k] = prmin;
 655             step[k]  = dp/10; // OPTIMIZE SEARCH STEP
 656         } // end for k
 657     } while( kTRUE );
 658     delete [] prm0;
 659     delete [] step;
 660     delete [] schi;
 661     delete [] sprm[0];
 662     delete [] sprm[1];
 663     delete [] sprm[2];
 664     delete [] speFit;
 665     return( out );
 666 }
 667 //______________________________________________________________________
 668 void AliITSClusterFinderSDD::ResolveClustersE(){
 669     // The function to resolve clusters if the clusters overlapping exists
 670     Int_t i;
 671     static AliITS *iTS = (AliITS*)gAlice->GetModule( "ITS" );
 672     // get number of clusters for this module
 673     Int_t nofClusters = fClusters->GetEntriesFast();
 674     nofClusters -= fNclusters;
 675     Int_t fNofMaps = fSegmentation->Npz();
 676     Int_t fNofAnodes = fNofMaps/2;
 677     Int_t fMaxNofSamples = fSegmentation->Npx();
 678     Int_t dummy=0;
 679     Double_t fTimeStep = fSegmentation->Dpx( dummy );
 680     Double_t fSddLength = fSegmentation->Dx();
 681     Double_t fDriftSpeed = fResponse->DriftSpeed();
 682     Double_t anodePitch = fSegmentation->Dpz( dummy );
 683     Float_t n, baseline;
 684     fResponse->GetNoiseParam( n, baseline );
 685     Int_t electronics = fResponse->Electronics(); // 1 = PASCAL, 2 = OLA
 686     // fill Map of signals
 687     fMap->FillMap();
 688     for( Int_t j=0; j<nofClusters; j++ ){
 689         // get cluster information
 690         AliITSRawClusterSDD *clusterJ=(AliITSRawClusterSDD*) fClusters->At(j);
 691         Int_t astart = clusterJ->Astart();
 692         Int_t astop = clusterJ->Astop();
 693         Int_t tstart = clusterJ->Tstartf();
 694         Int_t tstop = clusterJ->Tstopf();
 695         Int_t wing = (Int_t)clusterJ->W();
 696         if( wing == 2 ){
 697             astart += fNofAnodes;
 698             astop  += fNofAnodes;
 699         } // end if
 700         Int_t xdim = tstop-tstart+3;
 701         Int_t zdim = astop-astart+3;
 702         Float_t *sp = new Float_t[ xdim*zdim+1 ];
 703         memset( sp, 0, sizeof(Float_t)*(xdim*zdim+1) );
 704         // make a local map from cluster region
 705         for( Int_t ianode=astart; ianode<=astop; ianode++ ){
 706             for( Int_t itime=tstart; itime<=tstop; itime++ ){
 707                 Float_t fadc = fMap->GetSignal( ianode, itime );
 708                 if( fadc > baseline ) fadc -= (Double_t)baseline;
 709                 else fadc = 0.;
 710                 Int_t index = (itime-tstart+1)*zdim+(ianode-astart+1);
 711                 sp[index] = fadc;
 712             } // time loop
 713         } // anode loop
 714         // search peaks on cluster
 715         const Int_t kNp = 150;
 716         Int_t peakX1[kNp];
 717         Int_t peakZ1[kNp];
 718         Float_t peakAmp1[kNp];
 719         Int_t npeak = SearchPeak(sp,xdim,zdim,peakX1,peakZ1,peakAmp1,fMinPeak);
 720         // if multiple peaks, split cluster
 721         if( npeak >= 1 ){
 722             //  cout << "npeak " << npeak << endl;
 723             //  clusterJ->PrintInfo();
 724             Float_t *par = new Float_t[npeak*5+1];
 725             par[0] = (Float_t)npeak;
 726             // Initial paramiters in cell dimentions
 727             Int_t k1 = 1;
 728             for( i=0; i<npeak; i++ ){
 729                 par[k1] = peakAmp1[i];
 730                 par[k1+1] = peakX1[i]; // local time pos. [timebin]
 731                 par[k1+2] = peakZ1[i]; // local anode pos. [anodepitch]
 732                 if( electronics == 1 )
 733                     par[k1+3] = 2.; // PASCAL
 734                 else if( electronics == 2 )
 735                     par[k1+3] = 0.7; // tau [timebin]  OLA
 736                 par[k1+4] = .4;    // sigma     [anodepich]
 737                 k1+=5;
 738             } // end for i
 739             Int_t niter;
 740             Float_t chir;
 741             NoLinearFit( xdim, zdim, par, sp, &niter, &chir );
 742             Float_t peakX[kNp];
 743             Float_t peakZ[kNp];
 744             Float_t sigma[kNp];
 745             Float_t tau[kNp];
 746             Float_t peakAmp[kNp];
 747             Float_t integral[kNp];
 748             //get integrals => charge for each peak
 749             PeakFunc( xdim, zdim, par, sp, integral );
 750             k1 = 1;
 751             for( i=0; i<npeak; i++ ){
 752                 peakAmp[i] = par[k1];
 753                 peakX[i] = par[k1+1];
 754                 peakZ[i] = par[k1+2];
 755                 tau[i] = par[k1+3];
 756                 sigma[i] = par[k1+4];
 757                 k1+=5;
 758             } // end for i
 759             // calculate paramiter for new clusters
 760             for( i=0; i<npeak; i++ ){
 761                 AliITSRawClusterSDD clusterI( *clusterJ );
 762                 Int_t newAnode = peakZ1[i]-1 + astart;
 763                 Int_t newiTime = peakX1[i]-1 + tstart;
 764                 Int_t shift = (Int_t)(fTimeCorr/fTimeStep + 0.5);
 765                 if(newiTime>shift&&newiTime<(fMaxNofSamples-shift)) shift = 0;
 766                 Int_t peakpos = fMap->GetHitIndex( newAnode, newiTime+shift );
 767                 clusterI.SetPeakPos( peakpos );
 768                 clusterI.SetPeakAmpl( peakAmp1[i] );
 769                 Float_t newAnodef = peakZ[i] - 0.5 + astart;
 770                 Float_t newiTimef = peakX[i] - 1 + tstart;
 771                 if( wing == 2 ) newAnodef -= fNofAnodes;
 772                 Float_t anodePath = (newAnodef - fNofAnodes/2)*anodePitch;
 773                 newiTimef *= fTimeStep;
 774                 if( newiTimef > fTimeCorr ) newiTimef -= fTimeCorr;
 775                 if( electronics == 1 ){
 776                     newiTimef *= 0.999438;    // PASCAL
 777                     newiTimef += (6./fDriftSpeed - newiTimef/3000.);
 778                 }else if( electronics == 2 )
 779                     newiTimef *= 0.99714;    // OLA
 780                 Float_t driftPath = fSddLength - newiTimef * fDriftSpeed;
 781                 Float_t sign = ( wing == 1 ) ? -1. : 1.;
 782                 clusterI.SetX( driftPath*sign * 0.0001 );
 783                 clusterI.SetZ( anodePath * 0.0001 );
 784                 clusterI.SetAnode( newAnodef );
 785                 clusterI.SetTime( newiTimef );
 786                 clusterI.SetAsigma( sigma[i]*anodePitch );
 787                 clusterI.SetTsigma( tau[i]*fTimeStep );
 788                 clusterI.SetQ( integral[i] );
 789                 //      clusterI.PrintInfo();
 790                 iTS->AddCluster( 1, &clusterI );
 791             } // end for i
 792             fClusters->RemoveAt( j );
 793             delete [] par;
 794         } else cout <<" --- Peak not found!!!!  minpeak=" << fMinPeak<<
 795                    " cluster peak=" << clusterJ->PeakAmpl() << endl << endl;
 796         delete [] sp;
 797     } // cluster loop
 798     fClusters->Compress();
 799     fMap->ClearMap();
 800 }
 801 //________________________________________________________________________
 802 void  AliITSClusterFinderSDD::GroupClusters(){
 803     // group clusters
 804     Int_t dummy=0;
 805     Float_t fTimeStep = fSegmentation->Dpx(dummy);
 806     // get number of clusters for this module
 807     Int_t nofClusters = fClusters->GetEntriesFast();
 808     nofClusters -= fNclusters;
 809     AliITSRawClusterSDD *clusterI;
 810     AliITSRawClusterSDD *clusterJ;
 811     Int_t *label = new Int_t [nofClusters];
 812     Int_t i,j;
 813     for(i=0; i<nofClusters; i++) label[i] = 0;
 814     for(i=0; i<nofClusters; i++) {
 815         if(label[i] != 0) continue;
 816         for(j=i+1; j<nofClusters; j++) {
 817             if(label[j] != 0) continue;
 818             clusterI = (AliITSRawClusterSDD*) fClusters->At(i);
 819             clusterJ = (AliITSRawClusterSDD*) fClusters->At(j);
 820             // 1.3 good
 821             if(clusterI->T() < fTimeStep*60) fDAnode = 4.2;  // TB 3.2
 822             if(clusterI->T() < fTimeStep*10) fDAnode = 1.5;  // TB 1.
 823             Bool_t pair = clusterI->Brother(clusterJ,fDAnode,fDTime);
 824             if(!pair) continue;
 825             //      clusterI->PrintInfo();
 826             //      clusterJ->PrintInfo();
 827             clusterI->Add(clusterJ);
 828             label[j] = 1;
 829             fClusters->RemoveAt(j);
 830             j=i; // <- Ernesto
 831         } // J clusters
 832         label[i] = 1;
 833     } // I clusters
 834     fClusters->Compress();
 835
 836     delete [] label;
 837     return;
 838 }
 839 //________________________________________________________________________
 840 void AliITSClusterFinderSDD::SelectClusters(){
 841     // get number of clusters for this module
 842     Int_t nofClusters = fClusters->GetEntriesFast();
 843
 844     nofClusters -= fNclusters;
 845     Int_t i;
 846     for(i=0; i<nofClusters; i++) {
 847         AliITSRawClusterSDD *clusterI =(AliITSRawClusterSDD*) fClusters->At(i);
 848         Int_t rmflg = 0;
 849         Float_t wy = 0.;
 850         if(clusterI->Anodes() != 0.) {
 851             wy = ((Float_t) clusterI->Samples())/clusterI->Anodes();
 852         } // end if
 853         Int_t amp = (Int_t) clusterI->PeakAmpl();
 854         Int_t cha = (Int_t) clusterI->Q();
 855         if(amp < fMinPeak) rmflg = 1;
 856         if(cha < fMinCharge) rmflg = 1;
 857         if(wy < fMinNCells) rmflg = 1;
 858         //if(wy > fMaxNCells) rmflg = 1;
 859         if(rmflg) fClusters->RemoveAt(i);
 860     } // I clusters
 861     fClusters->Compress();
 862     return;
 863 }
 864 //__________________________________________________________________________
 865 void AliITSClusterFinderSDD::ResolveClusters(){
 866     // The function to resolve clusters if the clusters overlapping exists
 867 /*    AliITS *iTS=(AliITS*)gAlice->GetModule("ITS");
 868     // get number of clusters for this module
 869     Int_t nofClusters = fClusters->GetEntriesFast();
 870     nofClusters -= fNclusters;
 871     //cout<<"Resolve Cl: nofClusters, fNclusters ="<<nofClusters<<","
 872     // <<fNclusters<<endl;
 873     Int_t fNofMaps = fSegmentation->Npz();
 874     Int_t fNofAnodes = fNofMaps/2;
 875     Int_t dummy=0;
 876     Double_t fTimeStep = fSegmentation->Dpx(dummy);
 877     Double_t fSddLength = fSegmentation->Dx();
 878     Double_t fDriftSpeed = fResponse->DriftSpeed();
 879     Double_t anodePitch = fSegmentation->Dpz(dummy);
 880     Float_t n, baseline;
 881     fResponse->GetNoiseParam(n,baseline);
 882     Float_t dzz_1A = anodePitch * anodePitch / 12;
 883     // fill Map of signals
 884     fMap->FillMap();
 885     Int_t j,i,ii,ianode,anode,itime;
 886     Int_t wing,astart,astop,tstart,tstop,nanode;
 887     Double_t fadc,ClusterTime;
 888     Double_t q[400],x[400],z[400]; // digit charges and coordinates
 889     for(j=0; j<nofClusters; j++) {
 890         AliITSRawClusterSDD *clusterJ=(AliITSRawClusterSDD*) fClusters->At(j);
 891         Int_t ndigits = 0;
 892         astart=clusterJ->Astart();
 893         astop=clusterJ->Astop();
 894         tstart=clusterJ->Tstartf();
 895         tstop=clusterJ->Tstopf();
 896         nanode=clusterJ->Anodes();  // <- Ernesto
 897         wing=(Int_t)clusterJ->W();
 898         if(wing == 2) {
 899             astart += fNofAnodes;
 900             astop  += fNofAnodes;
 901         }  // end if
 902         // cout<<"astart,astop,tstart,tstop ="<<astart<<","<<astop<<","
 903         //      <<tstart<<","<<tstop<<endl;
 904         // clear the digit arrays
 905         for(ii=0; ii<400; ii++) {
 906             q[ii] = 0.;
 907             x[ii] = 0.;
 908             z[ii] = 0.;
 909         } // end for ii
 910
 911         for(ianode=astart; ianode<=astop; ianode++) {
 912             for(itime=tstart; itime<=tstop; itime++) {
 913                 fadc=fMap->GetSignal(ianode,itime);
 914                 if(fadc>baseline) {
 915                     fadc-=(Double_t)baseline;
 916                     q[ndigits] = fadc*(fTimeStep/160);  // KeV
 917                     anode = ianode;
 918                     if(wing == 2) anode -= fNofAnodes;
 919                     z[ndigits] = (anode + 0.5 - fNofAnodes/2)*anodePitch;
 920                     ClusterTime = itime*fTimeStep;
 921                     if(ClusterTime > fTimeCorr) ClusterTime -= fTimeCorr;// ns
 922                     x[ndigits] = fSddLength - ClusterTime*fDriftSpeed;
 923                     if(wing == 1) x[ndigits] *= (-1);
 924                     // cout<<"ianode,itime,fadc ="<<ianode<<","<<itime<<","
 925                     //     <<fadc<<endl;
 926                     // cout<<"wing,anode,ndigits,charge ="<<wing<<","
 927                     //      <<anode<<","<<ndigits<<","<<q[ndigits]<<endl;
 928                     ndigits++;
 929                     continue;
 930                 } //  end if
 931                 fadc=0;
 932                 //            cout<<"fadc=0, ndigits ="<<ndigits<<endl;
 933             } // time loop
 934         } // anode loop
 935         //     cout<<"for new cluster ndigits ="<<ndigits<<endl;
 936         // Fit cluster to resolve for two separate ones --------------------
 937         Double_t qq=0., xm=0., zm=0., xx=0., zz=0., xz=0.;
 938         Double_t dxx=0., dzz=0., dxz=0.;
 939         Double_t scl = 0., tmp, tga, elps = -1.;
 940         Double_t xfit[2], zfit[2], qfit[2];
 941         Double_t pitchz = anodePitch*1.e-4;             // cm
 942         Double_t pitchx = fTimeStep*fDriftSpeed*1.e-4;  // cm
 943         Double_t sigma2;
 944         Int_t nfhits;
 945         Int_t nbins = ndigits;
 946         Int_t separate = 0;
 947         // now, all lengths are in microns
 948         for (ii=0; ii<nbins; ii++) {
 949             qq += q[ii];
 950             xm += x[ii]*q[ii];
 951             zm += z[ii]*q[ii];
 952             xx += x[ii]*x[ii]*q[ii];
 953             zz += z[ii]*z[ii]*q[ii];
 954             xz += x[ii]*z[ii]*q[ii];
 955         } // end for ii
 956         xm /= qq;
 957         zm /= qq;
 958         xx /= qq;
 959         zz /= qq;
 960         xz /= qq;
 961         dxx = xx - xm*xm;
 962         dzz = zz - zm*zm;
 963         dxz = xz - xm*zm;
 964
 965         // shrink the cluster in the time direction proportionaly to the
 966         // dxx/dzz, which lineary depends from the drift path
 967         // new  Ernesto........
 968         if( nanode == 1 ){
 969             dzz = dzz_1A; // for one anode cluster dzz = anode**2/12
 970             scl = TMath::Sqrt( 7.2/(-0.57*xm*1.e-3+71.8) );
 971         } // end if
 972         if( nanode == 2 ){
 973             scl = TMath::Sqrt( (-0.18*xm*1.e-3+21.3)/(-0.57*xm*1.e-3+71.8) );
 974         } // end if
 975         if( nanode == 3 ){
 976             scl = TMath::Sqrt( (-0.5*xm*1.e-3+34.5)/(-0.57*xm*1.e-3+71.8) );
 977         } // end if
 978         if( nanode > 3 ){
 979             scl = TMath::Sqrt( (1.3*xm*1.e-3+49.)/(-0.57*xm*1.e-3+71.8) );
 980         } // end if
 981         //   cout<<"1 microns: zm,dzz,xm,dxx,dxz,qq ="<<zm<<","<<dzz<<","
 982         //  <<xm<<","<<dxx<<","<<dxz<<","<<qq<<endl;
 983         //  old Boris.........
 984         //  tmp=29730. - 585.*fabs(xm/1000.);
 985         //  scl=TMath::Sqrt(tmp/130000.);
 986
 987         xm *= scl;
 988         xx *= scl*scl;
 989         xz *= scl;
 990
 991         dxx = xx - xm*xm;
 992         //   dzz = zz - zm*zm;
 993         dxz = xz - xm*zm;
 994         //   cout<<"microns: zm,dzz,xm,dxx,xz,dxz,qq ="<<zm<<","<<dzz<<","
 995         // <<xm<<","<<dxx<<","<<xz<<","<<dxz<<","<<qq<<endl;
 996         // if(dzz < 7200.) dzz=7200.;//for one anode cluster dzz = anode**2/12
 997
 998         if (dxx < 0.) dxx=0.;
 999         // the data if no cluster overlapping (the coordunates are in cm)
1000         nfhits = 1;
1001         xfit[0] = xm*1.e-4;
1002         zfit[0] = zm*1.e-4;
1003         qfit[0] = qq;
1004         //   if(nbins < 7) cout<<"**** nbins ="<<nbins<<endl;
1005
1006         if (nbins >= 7) {
1007             if (dxz==0.) tga=0.;
1008             else {
1009                 tmp=0.5*(dzz-dxx)/dxz;
1010                 tga = (dxz<0.) ? tmp-TMath::Sqrt(tmp*tmp+1) :
1011                                                    tmp+TMath::Sqrt(tmp*tmp+1);
1012             } // end if dxz
1013             elps=(tga*tga*dxx-2*tga*dxz+dzz)/(dxx+2*tga*dxz+tga*tga*dzz);
1014             // change from microns to cm
1015             xm *= 1.e-4;
1016             zm *= 1.e-4;
1017             zz *= 1.e-8;
1018             xx *= 1.e-8;
1019             xz *= 1.e-8;
1020             dxz *= 1.e-8;
1021             dxx *= 1.e-8;
1022             dzz *= 1.e-8;
1023             //   cout<<"cm: zm,dzz,xm,dxx,xz,dxz,qq ="<<zm<<","<<dzz<<","
1024             //  <<xm<<","<<dxx<<","<<xz<<","<<dxz<<","<<qq<<endl;
1025             for (i=0; i<nbins; i++) {
1026                 x[i] = x[i] *= scl;
1027                 x[i] = x[i] *= 1.e-4;
1028                 z[i] = z[i] *= 1.e-4;
1029             } // end for i
1030             //     cout<<"!!! elps ="<<elps<<endl;
1031             if (elps < 0.3) { // try to separate hits
1032                 separate = 1;
1033                 tmp=atan(tga);
1034                 Double_t cosa=cos(tmp),sina=sin(tmp);
1035                 Double_t a1=0., x1=0., xxx=0.;
1036                 for (i=0; i<nbins; i++) {
1037                     tmp=x[i]*cosa + z[i]*sina;
1038                     if (q[i] > a1) {
1039                         a1=q[i];
1040                         x1=tmp;
1041                     } // end if
1042                     xxx += tmp*tmp*tmp*q[i];
1043                 } // end for i
1044                 xxx /= qq;
1045                 Double_t z12=-sina*xm + cosa*zm;
1046                 sigma2=(sina*sina*xx-2*cosa*sina*xz+cosa*cosa*zz) - z12*z12;
1047                 xm=cosa*xm + sina*zm;
1048                 xx=cosa*cosa*xx + 2*cosa*sina*xz + sina*sina*zz;
1049                 Double_t x2=(xx - xm*x1 - sigma2)/(xm - x1);
1050                 Double_t r=a1*2*TMath::ACos(-1.)*sigma2/(qq*pitchx*pitchz);
1051                 for (i=0; i<33; i++) { // solve a system of equations
1052                     Double_t x1_old=x1, x2_old=x2, r_old=r;
1053                     Double_t c11=x1-x2;
1054                     Double_t c12=r;
1055                     Double_t c13=1-r;
1056                     Double_t c21=x1*x1 - x2*x2;
1057                     Double_t c22=2*r*x1;
1058                     Double_t c23=2*(1-r)*x2;
1059                     Double_t c31=3*sigma2*(x1-x2) + x1*x1*x1 - x2*x2*x2;
1060                     Double_t c32=3*r*(sigma2 + x1*x1);
1061                     Double_t c33=3*(1-r)*(sigma2 + x2*x2);
1062                     Double_t f1=-(r*x1 + (1-r)*x2 - xm);
1063                     Double_t f2=-(r*(sigma2+x1*x1)+(1-r)*(sigma2+x2*x2)- xx);
1064                     Double_t f3=-(r*x1*(3*sigma2+x1*x1)+(1-r)*x2*
1065                                                          (3*sigma2+x2*x2)-xxx);
1066                     Double_t d=c11*c22*c33+c21*c32*c13+c12*c23*c31-
1067                                        c31*c22*c13 - c21*c12*c33 - c32*c23*c11;
1068                     if (d==0.) {
1069                         cout<<"*********** d=0 ***********\n";
1070                         break;
1071                     } // end if
1072                     Double_t dr=f1*c22*c33 + f2*c32*c13 + c12*c23*f3 -
1073                         f3*c22*c13 - f2*c12*c33 - c32*c23*f1;
1074                     Double_t d1=c11*f2*c33 + c21*f3*c13 + f1*c23*c31 -
1075                         c31*f2*c13 - c21*f1*c33 - f3*c23*c11;
1076                     Double_t d2=c11*c22*f3 + c21*c32*f1 + c12*f2*c31 -
1077                         c31*c22*f1 - c21*c12*f3 - c32*f2*c11;
1078                     r  += dr/d;
1079                     x1 += d1/d;
1080                     x2 += d2/d;
1081                     if (fabs(x1-x1_old) > 0.0001) continue;
1082                     if (fabs(x2-x2_old) > 0.0001) continue;
1083                     if (fabs(r-r_old)/5 > 0.001) continue;
1084                     a1=r*qq*pitchx*pitchz/(2*TMath::ACos(-1.)*sigma2);
1085                     Double_t a2=a1*(1-r)/r;
1086                     qfit[0]=a1; xfit[0]=x1*cosa - z12*sina; zfit[0]=x1*sina +
1087                                                                 z12*cosa;
1088                     qfit[1]=a2; xfit[1]=x2*cosa - z12*sina; zfit[1]=x2*sina +
1089                                                                 z12*cosa;
1090                     nfhits=2;
1091                     break; // Ok !
1092                 } // end for i
1093                 if (i==33) cerr<<"No more iterations ! "<<endl;
1094             } // end of attempt to separate overlapped clusters
1095         } // end of nbins cut
1096         if(elps < 0.) cout<<" elps=-1 ="<<elps<<endl;
1097         if(elps >0. && elps< 0.3 && nfhits == 1) cout<<" small elps, nfh=1 ="
1098                                                      <<elps<<","<<nfhits<<endl;
1099         if(nfhits == 2) cout<<" nfhits=2 ="<<nfhits<<endl;
1100         for (i=0; i<nfhits; i++) {
1101             xfit[i] *= (1.e+4/scl);
1102             if(wing == 1) xfit[i] *= (-1);
1103             zfit[i] *= 1.e+4;
1104             //       cout<<" ---------  i,xfiti,zfiti,qfiti ="<<i<<","
1105             // <<xfit[i]<<","<<zfit[i]<<","<<qfit[i]<<endl;
1106         } // end for i
1107         Int_t ncl = nfhits;
1108         if(nfhits == 1 && separate == 1) {
1109             cout<<"!!!!! no separate"<<endl;
1110             ncl = -2;
1111         }  // end if
1112         if(nfhits == 2) {
1113             cout << "Split cluster: " << endl;
1114             clusterJ->PrintInfo();
1115             cout << " in: " << endl;
1116             for (i=0; i<nfhits; i++) {
1117                 // AliITSRawClusterSDD *clust = new AliITSRawClusterSDD(wing,
1118                                                -1,-1,(Float_t)qfit[i],ncl,0,0,
1119                                                (Float_t)xfit[i],
1120                                                (Float_t)zfit[i],0,0,0,0,
1121                                                 tstart,tstop,astart,astop);
1122             //  AliITSRawClusterSDD *clust = new AliITSRawClusterSDD(wing,-1,
1123             //                                 -1,(Float_t)qfit[i],0,0,0,
1124             //                                  (Float_t)xfit[i],
1125             //                                  (Float_t)zfit[i],0,0,0,0,
1126             //                                  tstart,tstop,astart,astop,ncl);
1127             // ???????????
1128             // if(wing == 1) xfit[i] *= (-1);
1129             Float_t Anode = (zfit[i]/anodePitch+fNofAnodes/2-0.5);
1130             Float_t Time = (fSddLength - xfit[i])/fDriftSpeed;
1131             Float_t clusterPeakAmplitude = clusterJ->PeakAmpl();
1132             Float_t peakpos = clusterJ->PeakPos();
1133             Float_t clusteranodePath = (Anode - fNofAnodes/2)*anodePitch;
1134             Float_t clusterDriftPath = Time*fDriftSpeed;
1135             clusterDriftPath = fSddLength-clusterDriftPath;
1136             AliITSRawClusterSDD *clust = new AliITSRawClusterSDD(wing,Anode,
1137                                                                  Time,qfit[i],
1138                                                clusterPeakAmplitude,peakpos,
1139                                                0.,0.,clusterDriftPath,
1140                                          clusteranodePath,clusterJ->Samples()/2
1141                                     ,tstart,tstop,0,0,0,astart,astop);
1142             clust->PrintInfo();
1143             iTS->AddCluster(1,clust);
1144             //  cout<<"new cluster added: tstart,tstop,astart,astop,x,ncl ="
1145             // <<tstart<<","<<tstop<<","<<astart<<","<<astop<<","<<xfit[i]
1146             // <<","<<ncl<<endl;
1147             delete clust;
1148         }// nfhits loop
1149         fClusters->RemoveAt(j);
1150     } // if nfhits = 2
1151 } // cluster loop
1152 fClusters->Compress();
1153 fMap->ClearMap();
1154 */
1155     return;
1156 }
1157 //______________________________________________________________________
1158 void AliITSClusterFinderSDD::GetRecPoints(){
1159     // get rec points
1160     static AliITS *iTS=(AliITS*)gAlice->GetModule("ITS");
1161     // get number of clusters for this module
1162     Int_t nofClusters = fClusters->GetEntriesFast();
1163     nofClusters -= fNclusters;
1164     const Float_t kconvGeV = 1.e-6; // GeV -> KeV
1165     const Float_t kconv = 1.0e-4;
1166     const Float_t kRMSx = 38.0*kconv; // microns->cm ITS TDR Table 1.3
1167     const Float_t kRMSz = 28.0*kconv; // microns->cm ITS TDR Table 1.3
1168     Int_t i;
1169     Int_t ix, iz, idx=-1;
1170     AliITSdigitSDD *dig=0;
1171     Int_t ndigits=fDigits->GetEntriesFast();
1172     for(i=0; i<nofClusters; i++) {
1173         AliITSRawClusterSDD *clusterI = (AliITSRawClusterSDD*)fClusters->At(i);
1174         if(!clusterI) Error("SDD: GetRecPoints","i clusterI ",i,clusterI);
1175         if(clusterI) idx=clusterI->PeakPos();
1176         if(idx>ndigits) Error("SDD: GetRecPoints","idx ndigits",idx,ndigits);
1177         // try peak neighbours - to be done
1178         if(idx&&idx<= ndigits) dig =(AliITSdigitSDD*)fDigits->UncheckedAt(idx);
1179         if(!dig) {
1180             // try cog
1181             fSegmentation->GetPadIxz(clusterI->X(),clusterI->Z(),ix,iz);
1182             dig = (AliITSdigitSDD*)fMap->GetHit(iz-1,ix-1);
1183             // if null try neighbours
1184             if (!dig) dig = (AliITSdigitSDD*)fMap->GetHit(iz-1,ix);
1185             if (!dig) dig = (AliITSdigitSDD*)fMap->GetHit(iz-1,ix+1);
1186             if (!dig) printf("SDD: cannot assign the track number!\n");
1187         } //  end if !dig
1188         AliITSRecPoint rnew;
1189         rnew.SetX(clusterI->X());
1190         rnew.SetZ(clusterI->Z());
1191         rnew.SetQ(clusterI->Q());   // in KeV - should be ADC
1192         rnew.SetdEdX(kconvGeV*clusterI->Q());
1193         rnew.SetSigmaX2(kRMSx*kRMSx);
1194         rnew.SetSigmaZ2(kRMSz*kRMSz);
1195         if(dig) rnew.fTracks[0]=dig->fTracks[0];
1196         if(dig) rnew.fTracks[1]=dig->fTracks[1];
1197         if(dig) rnew.fTracks[2]=dig->fTracks[2];
1198         //printf("SDD: i %d track1 track2 track3 %d %d %d x y %f %f\n",
1199         //         i,rnew.fTracks[0],rnew.fTracks[1],rnew.fTracks[2],c
1200         //         lusterI->X(),clusterI->Z());
1201         iTS->AddRecPoint(rnew);
1202     } // I clusters
1203     fMap->ClearMap();
1204 }
1205 //______________________________________________________________________
1206 void AliITSClusterFinderSDD::FindRawClusters(Int_t mod){
1207     // find raw clusters
1208
1209     Find1DClustersE();
1210     GroupClusters();
1211     SelectClusters();
1212     ResolveClustersE();
1213     GetRecPoints();
1214 }
1215 //_______________________________________________________________________
1216 void AliITSClusterFinderSDD::Print(){
1217     // Print SDD cluster finder Parameters
1218
1219     cout << "**************************************************" << endl;
1220     cout << " Silicon Drift Detector Cluster Finder Parameters " << endl;
1221     cout << "**************************************************" << endl;
1222     cout << "Number of Clusters: " << fNclusters << endl;
1223     cout << "Anode Tolerance: " << fDAnode << endl;
1224     cout << "Time  Tolerance: " << fDTime << endl;
1225     cout << "Time  correction (electronics): " << fTimeCorr << endl;
1226     cout << "Cut Amplitude (threshold): " << fCutAmplitude << endl;
1227     cout << "Minimum Amplitude: " << fMinPeak << endl;
1228     cout << "Minimum Charge: " << fMinCharge << endl;
1229     cout << "Minimum number of cells/clusters: " << fMinNCells << endl;
1230     cout << "Maximum number of cells/clusters: " << fMaxNCells << endl;
1231     cout << "**************************************************" << endl;
1232 }