Removal of the last gAlice deps. In case of raw-data reconstruction and missing gAlic...
[u/mrichter/AliRoot.git] / TRD / AliTRDclusterizerV1.cxx
1
2 /**************************************************************************
3  * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
4  *                                                                        *
5  * Author: The ALICE Off-line Project.                                    *
6  * Contributors are mentioned in the code where appropriate.              *
7  *                                                                        *
8  * Permission to use, copy, modify and distribute this software and its   *
9  * documentation strictly for non-commercial purposes is hereby granted   *
10  * without fee, provided that the above copyright notice appears in all   *
11  * copies and that both the copyright notice and this permission notice   *
12  * appear in the supporting documentation. The authors make no claims     *
13  * about the suitability of this software for any purpose. It is          *
14  * provided "as is" without express or implied warranty.                  *
15  **************************************************************************/
16
17 /* $Id$ */
18
19 ///////////////////////////////////////////////////////////////////////////////
20 //                                                                           //
21 // TRD cluster finder                                                        //
22 //                                                                           //
23 ///////////////////////////////////////////////////////////////////////////////
24
25 #include <TF1.h>
26 #include <TTree.h>
27 #include <TH1.h>
28 #include <TFile.h>
29
30 #include "AliRunLoader.h"
31 #include "AliLoader.h"
32 #include "AliRawReader.h"
33 #include "AliLog.h"
34
35 #include "AliTRDclusterizerV1.h"
36 #include "AliTRDgeometry.h"
37 #include "AliTRDdataArrayF.h"
38 #include "AliTRDdataArrayI.h"
39 #include "AliTRDdigitsManager.h"
40 #include "AliTRDpadPlane.h"
41 #include "AliTRDrawData.h"
42 #include "AliTRDcalibDB.h"
43 #include "AliTRDSimParam.h"
44 #include "AliTRDRecParam.h"
45 #include "AliTRDCommonParam.h"
46 #include "AliTRDcluster.h"
47
48 #include "Cal/AliTRDCalROC.h"
49 #include "Cal/AliTRDCalDet.h"
50
51 ClassImp(AliTRDclusterizerV1)
52
53 //_____________________________________________________________________________
54 AliTRDclusterizerV1::AliTRDclusterizerV1()
55   :AliTRDclusterizer()
56   ,fDigitsManager(NULL)
57 {
58   //
59   // AliTRDclusterizerV1 default constructor
60   //
61
62 }
63
64 //_____________________________________________________________________________
65 AliTRDclusterizerV1::AliTRDclusterizerV1(const Text_t *name, const Text_t *title)
66   :AliTRDclusterizer(name,title)
67   ,fDigitsManager(new AliTRDdigitsManager())
68 {
69   //
70   // AliTRDclusterizerV1 constructor
71   //
72
73   fDigitsManager->CreateArrays();
74
75 }
76
77 //_____________________________________________________________________________
78 AliTRDclusterizerV1::AliTRDclusterizerV1(const AliTRDclusterizerV1 &c)
79   :AliTRDclusterizer(c)
80   ,fDigitsManager(NULL)
81 {
82   //
83   // AliTRDclusterizerV1 copy constructor
84   //
85
86 }
87
88 //_____________________________________________________________________________
89 AliTRDclusterizerV1::~AliTRDclusterizerV1()
90 {
91   //
92   // AliTRDclusterizerV1 destructor
93   //
94
95   if (fDigitsManager) {
96     delete fDigitsManager;
97     fDigitsManager = NULL;
98   }
99
100 }
101
102 //_____________________________________________________________________________
103 AliTRDclusterizerV1 &AliTRDclusterizerV1::operator=(const AliTRDclusterizerV1 &c)
104 {
105   //
106   // Assignment operator
107   //
108
109   if (this != &c) ((AliTRDclusterizerV1 &) c).Copy(*this);
110   return *this;
111
112 }
113
114 //_____________________________________________________________________________
115 void AliTRDclusterizerV1::Copy(TObject &c) const
116 {
117   //
118   // Copy function
119   //
120
121   ((AliTRDclusterizerV1 &) c).fDigitsManager = 0;
122
123   AliTRDclusterizer::Copy(c);
124
125 }
126
127 //_____________________________________________________________________________
128 Bool_t AliTRDclusterizerV1::ReadDigits()
129 {
130   //
131   // Reads the digits arrays from the input aliroot file
132   //
133
134   if (!fRunLoader) {
135     AliError("No run loader available");
136     return kFALSE;
137   }
138
139   AliLoader* loader = fRunLoader->GetLoader("TRDLoader");
140   if (!loader->TreeD()) {
141     loader->LoadDigits();
142   }
143
144   // Read in the digit arrays
145   return (fDigitsManager->ReadDigits(loader->TreeD()));
146
147 }
148
149 //_____________________________________________________________________________
150 Bool_t AliTRDclusterizerV1::ReadDigits(AliRawReader *rawReader)
151 {
152   //
153   // Reads the digits arrays from the ddl file
154   //
155
156   AliTRDrawData raw;
157   fDigitsManager = raw.Raw2Digits(rawReader);
158
159   return kTRUE;
160
161 }
162
163 //_____________________________________________________________________________
164 Bool_t AliTRDclusterizerV1::MakeClusters()
165 {
166   //
167   // Generates the cluster.
168   //
169
170   Int_t row   = 0;
171   Int_t col   = 0;
172   Int_t time  = 0;
173   Int_t icham = 0;
174   Int_t iplan = 0;
175   Int_t isect = 0;
176   Int_t iPad  = 0;
177     
178   AliTRDdataArrayI *digitsIn;
179   AliTRDdataArrayI *tracksIn;
180
181   // Get the geometry
182   AliTRDgeometry *geo            = AliTRDgeometry::GetGeometry(fRunLoader);  
183   if (!geo) {
184     AliWarning("Loading default TRD geometry!");
185     geo = new AliTRDgeometry();
186   }
187
188   AliTRDcalibDB  *calibration    = AliTRDcalibDB::Instance();
189   if (!calibration) {
190     AliFatal("No AliTRDcalibDB instance available\n");
191     return kFALSE;  
192   }
193   
194   AliTRDSimParam *simParam       = AliTRDSimParam::Instance();
195   if (!simParam) {
196     AliError("No AliTRDSimParam instance available\n");
197     return kFALSE;  
198   }
199   
200   AliTRDRecParam *recParam       = AliTRDRecParam::Instance();
201   if (!recParam) {
202     AliError("No AliTRDRecParam instance available\n");
203     return kFALSE;  
204   }
205   
206   AliTRDCommonParam *commonParam = AliTRDCommonParam::Instance();
207   if (!commonParam) {
208     AliError("Could not get common parameters\n");
209     return kFALSE;
210   }
211
212   // ADC threshols
213   Float_t ADCthreshold   = simParam->GetADCthreshold();
214   // Threshold value for the maximum
215   Float_t maxThresh      = recParam->GetClusMaxThresh();
216   // Threshold value for the digit signal
217   Float_t sigThresh      = recParam->GetClusSigThresh();
218
219   // Detector wise calibration object for t0
220   const AliTRDCalDet *calT0Det = calibration->GetT0Det();
221
222   // Iteration limit for unfolding procedure
223   const Float_t kEpsilon = 0.01;             
224   const Int_t   kNclus   = 3;  
225   const Int_t   kNsig    = 5;
226   const Int_t   kNdict   = AliTRDdigitsManager::kNDict;
227   const Int_t   kNtrack  = kNdict * kNclus;
228
229   Int_t    iType         = 0;
230   Int_t    iUnfold       = 0;  
231   Double_t ratioLeft     = 1.0;
232   Double_t ratioRight    = 1.0;
233
234   Int_t    iClusterROC   = 0;
235
236   Double_t padSignal[kNsig];   
237   Double_t clusterSignal[kNclus];
238   Double_t clusterPads[kNclus];   
239
240   Int_t    chamBeg    = 0;
241   Int_t    chamEnd    = AliTRDgeometry::Ncham();
242   Int_t    planBeg    = 0;
243   Int_t    planEnd    = AliTRDgeometry::Nplan();
244   Int_t    sectBeg    = 0;
245   Int_t    sectEnd    = AliTRDgeometry::Nsect();
246   Int_t    nTimeTotal = calibration->GetNumberOfTimeBins();
247
248   Int_t    dummy[9]   = { 0, 0, 0, 0, 0, 0, 0, 0, 0 };
249
250   AliDebug(1,Form("Number of Time Bins = %d.\n",nTimeTotal));
251
252   // Start clustering in every chamber
253   for (icham = chamBeg; icham < chamEnd; icham++) {
254     for (iplan = planBeg; iplan < planEnd; iplan++) {
255       for (isect = sectBeg; isect < sectEnd; isect++) {
256
257         Int_t idet = geo->GetDetector(iplan,icham,isect);
258
259         // Get the digits
260         digitsIn = fDigitsManager->GetDigits(idet);
261         // This is to take care of switched off super modules
262         if (digitsIn->GetNtime() == 0) {
263           continue;
264         }
265         digitsIn->Expand();
266         AliTRDdataArrayI *tracksTmp = fDigitsManager->GetDictionary(idet,0);
267         tracksTmp->Expand();
268
269         Int_t nRowMax = commonParam->GetRowMax(iplan,icham,isect);
270         Int_t nColMax = commonParam->GetColMax(iplan);
271
272         AliTRDpadPlane *padPlane = commonParam->GetPadPlane(iplan,icham);
273
274         // Calibration object with pad wise values for t0
275         AliTRDCalROC *calT0ROC      = calibration->GetT0ROC(idet);
276         // Calibration value for chamber wise t0
277         Float_t       calT0DetValue = calT0Det->GetValue(idet);
278
279         Int_t nClusters      = 0;
280         Int_t nClusters2pad  = 0;
281         Int_t nClusters3pad  = 0;
282         Int_t nClusters4pad  = 0;
283         Int_t nClusters5pad  = 0;
284         Int_t nClustersLarge = 0;
285
286         // Apply the gain and the tail cancelation via digital filter
287         AliTRDdataArrayF *digitsOut = new AliTRDdataArrayF(digitsIn->GetNrow()
288                                                           ,digitsIn->GetNcol()
289                                                           ,digitsIn->GetNtime());
290         Transform(digitsIn,digitsOut,idet,nRowMax,nColMax,nTimeTotal,ADCthreshold);
291
292         // Input digits are not needed any more
293         digitsIn->Compress(1,0);
294
295         // Loop through the chamber and find the maxima 
296         for ( row = 0;  row <  nRowMax;    row++) {
297           for ( col = 2;  col <  nColMax;    col++) {
298             for (time = 0; time < nTimeTotal; time++) {
299
300               Float_t signalM = TMath::Abs(digitsOut->GetDataUnchecked(row,col-1,time));
301  
302               // Look for the maximum
303               if (signalM >= maxThresh) {
304
305                 Float_t signalL = TMath::Abs(digitsOut->GetDataUnchecked(row,col  ,time));
306                 Float_t signalR = TMath::Abs(digitsOut->GetDataUnchecked(row,col-2,time));
307
308                 if ((TMath::Abs(signalL) <= signalM) && 
309                     (TMath::Abs(signalR) <  signalM)) {
310                   if ((TMath::Abs(signalL) >= sigThresh) ||
311                       (TMath::Abs(signalR) >= sigThresh)) {
312                     // Maximum found, mark the position by a negative signal
313                     digitsOut->SetDataUnchecked(row,col-1,time,-signalM);
314                   }
315                 }
316
317               }
318
319             }
320           }
321         }
322         tracksTmp->Compress(1,0);
323
324         // The index to the first cluster of a given ROC
325         Int_t firstClusterROC = -1;
326         // The number of cluster in a given ROC
327         Int_t nClusterROC     =  0;
328
329         // Now check the maxima and calculate the cluster position
330         for ( row = 0;  row <  nRowMax  ;  row++) {
331           for (time = 0; time < nTimeTotal; time++) {
332             for ( col = 1;  col <  nColMax-1;  col++) {
333
334               // Maximum found ?             
335               if (digitsOut->GetDataUnchecked(row,col,time) < 0.0) {
336
337                 for (iPad = 0; iPad < kNclus; iPad++) {
338                   Int_t iPadCol = col - 1 + iPad;
339                   clusterSignal[iPad] = 
340                     TMath::Abs(digitsOut->GetDataUnchecked(row,iPadCol,time));
341                 }
342
343                 // Count the number of pads in the cluster
344                 Int_t nPadCount = 0;
345                 Int_t ii;
346                 // Look to the left
347                 ii = 0;
348                 while (TMath::Abs(digitsOut->GetDataUnchecked(row,col-ii  ,time)) >= sigThresh) {
349                   nPadCount++;
350                   ii++;
351                   if (col-ii   <        0) break;
352                 }
353                 // Look to the right
354                 ii = 0;
355                 while (TMath::Abs(digitsOut->GetDataUnchecked(row,col+ii+1,time)) >= sigThresh) {
356                   nPadCount++;
357                   ii++;
358                   if (col+ii+1 >= nColMax) break;
359                 }
360                 nClusters++;
361                 switch (nPadCount) {
362                 case 2:
363                   iType = 0;
364                   nClusters2pad++;
365                   break;
366                 case 3:
367                   iType = 1;
368                   nClusters3pad++;
369                   break;
370                 case 4:
371                   iType = 2;
372                   nClusters4pad++;
373                   break;
374                 case 5:
375                   iType = 3;
376                   nClusters5pad++;
377                   break;
378                 default:
379                   iType = 4;
380                   nClustersLarge++;
381                   break;
382                 };
383
384                 // Look for 5 pad cluster with minimum in the middle
385                 Bool_t fivePadCluster = kFALSE;
386                 if (col < (nColMax - 3)) {
387                   if (digitsOut->GetDataUnchecked(row,col+2,time) < 0) {
388                     fivePadCluster = kTRUE;
389                   }
390                   if ((fivePadCluster) && (col < (nColMax - 5))) {
391                     if (digitsOut->GetDataUnchecked(row,col+4,time) >= sigThresh) {
392                       fivePadCluster = kFALSE;
393                     }
394                   }
395                   if ((fivePadCluster) && (col >             1)) {
396                     if (digitsOut->GetDataUnchecked(row,col-2,time) >= sigThresh) {
397                       fivePadCluster = kFALSE;
398                     }
399                   }
400                 }
401
402                 // 5 pad cluster
403                 // Modify the signal of the overlapping pad for the left part 
404                 // of the cluster which remains from a previous unfolding
405                 if (iUnfold) {
406                   clusterSignal[0] *= ratioLeft;
407                   iType   = 5;
408                   iUnfold = 0;
409                 }
410
411                 // Unfold the 5 pad cluster
412                 if (fivePadCluster) {
413                   for (iPad = 0; iPad < kNsig; iPad++) {
414                     padSignal[iPad] = TMath::Abs(digitsOut->GetDataUnchecked(row
415                                                                             ,col-1+iPad
416                                                                             ,time));
417                   }
418                   // Unfold the two maxima and set the signal on 
419                   // the overlapping pad to the ratio
420                   ratioRight        = Unfold(kEpsilon,iplan,padSignal);
421                   ratioLeft         = 1.0 - ratioRight; 
422                   clusterSignal[2] *= ratioRight;
423                   iType   = 5;
424                   iUnfold = 1;
425                 }
426
427                 Double_t clusterCharge = clusterSignal[0]
428                                        + clusterSignal[1]
429                                        + clusterSignal[2];
430                 
431                 // The position of the cluster
432                 clusterPads[0] =  row + 0.5;
433                 // Take the shift of the additional time bins into account
434                 clusterPads[2] = time + 0.5;
435
436                 if (recParam->LUTOn()) {
437                   // Calculate the position of the cluster by using the
438                   // lookup table method
439                   clusterPads[1] = recParam->LUTposition(iplan,clusterSignal[0]
440                                                               ,clusterSignal[1]
441                                                               ,clusterSignal[2]);
442                 }
443                 else {
444                   // Calculate the position of the cluster by using the
445                   // center of gravity method
446                   for (Int_t i = 0; i < kNsig; i++) {
447                     padSignal[i] = 0.0;
448                   }
449                   padSignal[2] = TMath::Abs(digitsOut->GetDataUnchecked(row,col  ,time)); // Central pad
450                   padSignal[1] = TMath::Abs(digitsOut->GetDataUnchecked(row,col-1,time)); // Left    pad
451                   padSignal[3] = TMath::Abs(digitsOut->GetDataUnchecked(row,col+1,time)); // Right   pad
452                   if ((col >           2) && 
453                       (TMath::Abs(digitsOut->GetDataUnchecked(row,col-2,time)) < padSignal[1])) {
454                     padSignal[0] = TMath::Abs(digitsOut->GetDataUnchecked(row,col-2,time));
455                   }
456                   if ((col < nColMax - 3) &&
457                       (TMath::Abs(digitsOut->GetDataUnchecked(row,col+2,time)) < padSignal[3])) {
458                     padSignal[4] = TMath::Abs(digitsOut->GetDataUnchecked(row,col+2,time));
459                   }               
460                   clusterPads[1] = GetCOG(padSignal);
461                 }
462
463                 Double_t q0 = clusterSignal[0];
464                 Double_t q1 = clusterSignal[1];
465                 Double_t q2 = clusterSignal[2];
466                 Double_t clusterSigmaY2 = (q1 * (q0 + q2) + 4.0 * q0 * q2)
467                                         / (clusterCharge*clusterCharge);
468
469                 //
470                 // Calculate the position and the error
471                 //              
472
473                 // Correct for t0 (sum of chamber and pad wise values !!!)
474                 Float_t  calT0ROCValue  = calT0ROC->GetValue(col,row);
475                 Int_t    clusterTimeBin = TMath::Nint(time - (calT0DetValue + calT0ROCValue));
476                 Double_t colSize        = padPlane->GetColSize(col);
477                 Double_t rowSize        = padPlane->GetRowSize(row);
478
479                 Double_t clusterPos[3];
480                 clusterPos[0] = padPlane->GetColPos(col) - (clusterPads[1] + 0.5) * colSize;
481                 clusterPos[1] = padPlane->GetRowPos(row) - 0.5                    * rowSize;
482                 clusterPos[2] = CalcXposFromTimebin(clusterPads[2],idet,col,row);
483                 Double_t clusterSig[2];
484                 clusterSig[0] = (clusterSigmaY2 + 1.0/12.0) * colSize*colSize;
485                 clusterSig[1] = rowSize * rowSize / 12.0;                                       
486                 
487                 // Add the cluster to the output array
488                 // The track indices will be stored later 
489                 AliTRDcluster *cluster = AddCluster(clusterPos
490                                                    ,clusterTimeBin
491                                                    ,idet
492                                                    ,clusterCharge
493                                                    ,dummy
494                                                    ,clusterSig
495                                                    ,iType
496                                                    ,clusterPads[1]);
497
498                 // Store the amplitudes of the pads in the cluster for later analysis
499                 Short_t signals[7] = { 0, 0, 0, 0, 0, 0, 0 };
500                 for (Int_t jPad = col-3; jPad <= col+3; jPad++) {
501                   if ((jPad <          0) || 
502                       (jPad >= nColMax-1)) {
503                     continue;
504                   }
505                   signals[jPad-col+3] = TMath::Nint(TMath::Abs(digitsOut->GetDataUnchecked(row,jPad,time)));
506                 }
507                 cluster->SetSignals(signals);
508
509                 // Temporarily store the row, column and time bin of the center pad
510                 // Used to later on assign the track indices
511                 cluster->SetLabel( row,0);
512                 cluster->SetLabel( col,1);
513                 cluster->SetLabel(time,2);
514
515                 // Store the index of the first cluster in the current ROC
516                 if (firstClusterROC < 0) {
517                   firstClusterROC = RecPoints()->GetEntriesFast() - 1;
518                 }
519                 // Count the number of cluster in the current ROC
520                 nClusterROC++;
521
522               } // if: Maximum found ?
523
524             } // loop: pad columns
525           } // loop: time bins
526         } // loop: pad rows
527
528         delete digitsOut;
529
530         //
531         // Add the track indices to the found clusters
532         //
533
534         // Temporary array to collect the track indices
535         Int_t *idxTracks = new Int_t[kNtrack*nClusterROC];
536
537         // Loop through the dictionary arrays one-by-one
538         // to keep memory consumption low
539         for (Int_t iDict = 0; iDict < kNdict; iDict++) {
540
541           tracksIn = fDigitsManager->GetDictionary(idet,iDict);
542           tracksIn->Expand();
543
544           // Loop though the clusters found in this ROC
545           for (iClusterROC = 0; iClusterROC < nClusterROC; iClusterROC++) {
546  
547             AliTRDcluster *cluster = (AliTRDcluster *)
548                                      RecPoints()->UncheckedAt(firstClusterROC+iClusterROC);
549             row  = cluster->GetLabel(0);
550             col  = cluster->GetLabel(1);
551             time = cluster->GetLabel(2);
552
553             for (iPad = 0; iPad < kNclus; iPad++) {
554               Int_t iPadCol = col - 1 + iPad;
555               Int_t index   = tracksIn->GetDataUnchecked(row,iPadCol,time) - 1;
556               idxTracks[3*iPad+iDict + iClusterROC*kNtrack] = index;     
557             }
558
559           }
560
561           // Compress the arrays
562           tracksIn->Compress(1,0);
563
564         }
565
566         // Copy the track indices into the cluster
567         // Loop though the clusters found in this ROC
568         for (iClusterROC = 0; iClusterROC < nClusterROC; iClusterROC++) {
569  
570           AliTRDcluster *cluster = (AliTRDcluster *)
571                                    RecPoints()->UncheckedAt(firstClusterROC+iClusterROC);
572           cluster->SetLabel(-9999,0);
573           cluster->SetLabel(-9999,1);
574           cluster->SetLabel(-9999,2);
575   
576           cluster->AddTrackIndex(&idxTracks[iClusterROC*kNtrack]);
577
578         }
579
580         delete [] idxTracks;
581
582         // Write the cluster and reset the array
583         WriteClusters(idet);
584         ResetRecPoints();
585
586       } // loop: Sectors
587     } // loop: Planes
588   } // loop: Chambers
589
590   return kTRUE;
591
592 }
593
594 //_____________________________________________________________________________
595 Double_t AliTRDclusterizerV1::GetCOG(Double_t signal[5])
596 {
597   //
598   // Get COG position
599   // Used for clusters with more than 3 pads - where LUT not applicable
600   //
601
602   Double_t sum = signal[0]
603                + signal[1]
604                + signal[2] 
605                + signal[3]
606                + signal[4];
607
608   Double_t res = (0.0 * (-signal[0] + signal[4])
609                       + (-signal[1] + signal[3])) / sum;
610
611   return res;             
612
613 }
614
615 //_____________________________________________________________________________
616 Double_t AliTRDclusterizerV1::Unfold(Double_t eps, Int_t plane, Double_t *padSignal)
617 {
618   //
619   // Method to unfold neighbouring maxima.
620   // The charge ratio on the overlapping pad is calculated
621   // until there is no more change within the range given by eps.
622   // The resulting ratio is then returned to the calling method.
623   //
624
625   AliTRDcalibDB *calibration = AliTRDcalibDB::Instance();
626   if (!calibration) {
627     AliError("No AliTRDcalibDB instance available\n");
628     return kFALSE;  
629   }
630   
631   Int_t   irc                = 0;
632   Int_t   itStep             = 0;                 // Count iteration steps
633
634   Double_t ratio             = 0.5;               // Start value for ratio
635   Double_t prevRatio         = 0.0;               // Store previous ratio
636
637   Double_t newLeftSignal[3]  = { 0.0, 0.0, 0.0 }; // Array to store left cluster signal
638   Double_t newRightSignal[3] = { 0.0, 0.0, 0.0 }; // Array to store right cluster signal
639   Double_t newSignal[3]      = { 0.0, 0.0, 0.0 };
640
641   // Start the iteration
642   while ((TMath::Abs(prevRatio - ratio) > eps) && (itStep < 10)) {
643
644     itStep++;
645     prevRatio = ratio;
646
647     // Cluster position according to charge ratio
648     Double_t maxLeft  = (ratio*padSignal[2] - padSignal[0]) 
649                       / (padSignal[0] + padSignal[1] + ratio*padSignal[2]);
650     Double_t maxRight = (padSignal[4] - (1-ratio)*padSignal[2]) 
651                       / ((1.0 - ratio)*padSignal[2] + padSignal[3] + padSignal[4]);
652
653     // Set cluster charge ratio
654     irc = calibration->PadResponse(1.0,maxLeft ,plane,newSignal);
655     Double_t ampLeft  = padSignal[1] / newSignal[1];
656     irc = calibration->PadResponse(1.0,maxRight,plane,newSignal);
657     Double_t ampRight = padSignal[3] / newSignal[1];
658
659     // Apply pad response to parameters
660     irc = calibration->PadResponse(ampLeft ,maxLeft ,plane,newLeftSignal );
661     irc = calibration->PadResponse(ampRight,maxRight,plane,newRightSignal);
662
663     // Calculate new overlapping ratio
664     ratio = TMath::Min((Double_t)1.0,newLeftSignal[2] / 
665                                     (newLeftSignal[2] + newRightSignal[0]));
666
667   }
668
669   return ratio;
670
671 }
672
673 //_____________________________________________________________________________
674 void AliTRDclusterizerV1::Transform(AliTRDdataArrayI *digitsIn
675                                   , AliTRDdataArrayF *digitsOut
676                                   , Int_t idet, Int_t nRowMax
677                                   , Int_t nColMax, Int_t nTimeTotal
678                                   , Float_t ADCthreshold)
679 {
680   //
681   // Apply gain factor
682   // Apply tail cancelation: Transform digitsIn to digitsOut
683   //
684
685   Int_t iRow  = 0;
686   Int_t iCol  = 0;
687   Int_t iTime = 0;
688
689   AliTRDRecParam *recParam = AliTRDRecParam::Instance();
690   if (!recParam) {
691     AliError("No AliTRDRecParam instance available\n");
692     return;
693   }
694   AliTRDcalibDB *calibration = AliTRDcalibDB::Instance();
695   if (!calibration) {
696     AliError("No AliTRDcalibDB instance available\n");
697     return;  
698   }
699
700   Double_t *inADC  = new Double_t[nTimeTotal];  // ADC data before tail cancellation
701   Double_t *outADC = new Double_t[nTimeTotal];  // ADC data after tail cancellation
702
703   AliDebug(1,Form("Tail cancellation (nExp = %d) for detector %d.\n"
704                  ,recParam->GetTCnexp(),idet));
705
706   // Calibration object with chamber wise values for the gain factor
707   const AliTRDCalDet *calGainFactorDet      = calibration->GetGainFactorDet();
708   // Calibration object with pad wise values for the gain factor
709   AliTRDCalROC       *calGainFactorROC      = calibration->GetGainFactorROC(idet);
710   // Calibration value for chamber wise gain factors
711   Float_t             calGainFactorDetValue = calGainFactorDet->GetValue(idet);
712
713   for (iRow  = 0; iRow  <  nRowMax;   iRow++ ) {
714     for (iCol  = 0; iCol  <  nColMax;   iCol++ ) {
715
716       Float_t  calGainFactorROCValue = calGainFactorROC->GetValue(iCol,iRow);
717       Double_t gain                  = calGainFactorDetValue 
718                                      * calGainFactorROCValue;
719
720       for (iTime = 0; iTime < nTimeTotal; iTime++) {
721
722         //
723         // Add gain
724         //
725         inADC[iTime]   = digitsIn->GetDataUnchecked(iRow,iCol,iTime);
726         inADC[iTime]  /= gain;
727         outADC[iTime]  = inADC[iTime];
728
729       }
730
731       // Apply the tail cancelation via the digital filter
732       if (recParam->TCOn()) {
733         DeConvExp(inADC,outADC,nTimeTotal,recParam->GetTCnexp());
734       }
735
736       for (iTime = 0; iTime < nTimeTotal; iTime++) {
737
738         // Store the amplitude of the digit if above threshold
739         if (outADC[iTime] > ADCthreshold) {
740           digitsOut->SetDataUnchecked(iRow,iCol,iTime,outADC[iTime]);
741         }
742
743       }
744
745     }
746   }
747
748   delete [] inADC;
749   delete [] outADC;
750
751   return;
752
753 }
754
755 //_____________________________________________________________________________
756 void AliTRDclusterizerV1::DeConvExp(Double_t *source, Double_t *target
757                                   , Int_t n, Int_t nexp) 
758 {
759   //
760   // Tail cancellation by deconvolution for PASA v4 TRF
761   //
762
763   Double_t rates[2];
764   Double_t coefficients[2];
765
766   // Initialization (coefficient = alpha, rates = lambda)
767   Double_t R1 = 1.0;
768   Double_t R2 = 1.0;
769   Double_t C1 = 0.5;
770   Double_t C2 = 0.5;
771
772   if (nexp == 1) {   // 1 Exponentials
773     R1 = 1.156;
774     R2 = 0.130;
775     C1 = 0.066;
776     C2 = 0.000;
777   }
778   if (nexp == 2) {   // 2 Exponentials
779     R1 = 1.156;
780     R2 = 0.130;
781     C1 = 0.114;
782     C2 = 0.624;
783   }
784
785   coefficients[0] = C1;
786   coefficients[1] = C2;
787
788   Double_t Dt = 0.1;
789
790   rates[0] = TMath::Exp(-Dt/(R1));
791   rates[1] = TMath::Exp(-Dt/(R2));
792   
793   Int_t i = 0;
794   Int_t k = 0;
795
796   Double_t reminder[2];
797   Double_t correction;
798   Double_t result;
799
800   // Attention: computation order is important
801   correction = 0.0;
802   for (k = 0; k < nexp; k++) {
803     reminder[k] = 0.0;
804   }
805   for (i = 0; i < n; i++) {
806     result    = (source[i] - correction);    // No rescaling
807     target[i] = result;
808
809     for (k = 0; k < nexp; k++) {
810       reminder[k] = rates[k] * (reminder[k] + coefficients[k] * result);
811     }
812     correction = 0.0;
813     for (k = 0; k < nexp; k++) {
814       correction += reminder[k];
815     }
816   }
817
818 }