1 /**************************************************************************
2 * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
4 * Author: The ALICE Off-line Project. *
5 * Contributors are mentioned in the code where appropriate. *
7 * Permission to use, copy, modify and distribute this software and its *
8 * documentation strictly for non-commercial purposes is hereby granted *
9 * without fee, provided that the above copyright notice appears in all *
10 * copies and that both the copyright notice and this permission notice *
11 * appear in the supporting documentation. The authors make no claims *
12 * about the suitability of this software for any purpose. It is *
13 * provided "as is" without express or implied warranty. *
14 **************************************************************************/
18 ///////////////////////////////////////////////////////////////////////////
20 // Creation and investigation of a jet of particle tracks.
21 // An AliJet can be constructed by adding AliTracks.
23 // To provide maximal flexibility to the user, two modes of track storage
24 // are provided by means of the memberfunction SetTrackCopy().
26 // a) SetTrackCopy(0) (which is the default).
27 // Only the pointers of the 'added' tracks are stored.
28 // This mode is typically used by making jet studies based on a fixed list
29 // of tracks which stays under user control or is contained for instance
31 // In this way the AliJet just represents a 'logical structure' for the
32 // physics analysis which can be embedded in e.g. an AliEvent or AliVertex.
35 // Modifications made to the original tracks also affect the AliTrack objects
36 // which are stored in the AliJet.
38 // b) SetTrackCopy(1).
39 // Of every 'added' track a private copy will be made of which the pointer
41 // In this way the AliJet represents an entity on its own and modifications
42 // made to the original tracks do not affect the AliTrack objects which are
43 // stored in the AliJet.
44 // This mode will allow 'adding' many different AliTracks into an AliJet by
45 // creating only one AliTrack instance in the main programme and using the
46 // AliTrack::Reset() and AliTrack parameter setting memberfunctions.
48 // See also the documentation provided for the memberfunction SetOwner().
50 // Coding example to make 2 jets j1 and j2.
51 // ----------------------------------------
52 // j1 contains the AliTracks t1 and t2
53 // j2 contains 10 different AliTracks via tx
57 // ... // code to fill the AliTrack data
64 // j2.SetTrackCopy(1);
65 // AliTrack* tx=new AliTrack();
66 // for (Int_t i=0; i<10; i++)
69 // ... // code to set momentum etc... of the track tx
78 // Float_t e1=j1.GetEnergy();
79 // Float_t pnorm=j1->GetMomentum();
80 // Ali3Vector p=j1->Get3Momentum();
81 // Float_t m=j1.GetInvmass();
82 // Int_t ntk=j1.GetNtracks();
83 // AliTrack* tj=j1.GetTrack(1);
87 // Note : All quantities are in GeV, GeV/c or GeV/c**2
89 //--- Author: Nick van Eijndhoven 10-jul-1997 UU-SAP Utrecht
90 //- Modified: NvE $Date$ UU-SAP Utrecht
91 ///////////////////////////////////////////////////////////////////////////
94 #include "Riostream.h"
96 ClassImp(AliJet) // Class implementation to enable ROOT I/O
98 AliJet::AliJet() : TNamed(),Ali4Vector()
100 // Default constructor
101 // All variables initialised to 0
102 // Initial maximum number of tracks is set to the default value
107 ///////////////////////////////////////////////////////////////////////////
110 // Initialisation of pointers etc...
115 ///////////////////////////////////////////////////////////////////////////
116 AliJet::AliJet(Int_t n) : TNamed(),Ali4Vector()
118 // Create a jet to hold initially a maximum of n tracks
119 // All variables initialised to 0
129 cout << " *AliJet* Initial max. number of tracks entered : " << n << endl;
130 cout << " This is invalid. Default initial maximum will be used." << endl;
135 ///////////////////////////////////////////////////////////////////////////
138 // Default destructor
145 ///////////////////////////////////////////////////////////////////////////
146 void AliJet::SetOwner(Bool_t own)
148 // Set ownership of all added objects.
149 // The default parameter is own=kTRUE.
151 // Invokation of this memberfunction also sets all the copy modes
152 // (e.g. TrackCopy & co.) according to the value of own.
154 // This function (with own=kTRUE) is particularly useful when reading data
155 // from a tree/file, since Reset() will then actually remove all the
156 // added objects from memory irrespective of the copy mode settings
157 // during the tree/file creation process. In this way it provides a nice way
158 // of preventing possible memory leaks in the reading/analysis process.
160 // In addition this memberfunction can also be used as a shortcut to set all
161 // copy modes in one go during a tree/file creation process.
162 // However, in this case the user has to take care to only set/change the
163 // ownership (and copy mode) for empty objects (e.g. newly created objects
164 // or after invokation of the Reset() memberfunction) otherwise it will
165 // very likely result in inconsistent destructor behaviour.
169 if (fTracks) fTracks->SetOwner(own);
172 ///////////////////////////////////////////////////////////////////////////
173 AliJet::AliJet(const AliJet& j) : TNamed(j),Ali4Vector(j)
180 fTrackCopy=j.fTrackCopy;
186 fTracks=new TObjArray(fNtmax);
187 if (fTrackCopy) fTracks->SetOwner();
190 for (Int_t i=1; i<=fNtrk; i++)
192 AliTrack* tx=j.GetTrack(i);
195 fTracks->Add(tx->Clone());
203 ///////////////////////////////////////////////////////////////////////////
204 void AliJet::SetNtinit(Int_t n)
206 // Set the initial maximum number of tracks for this jet
215 ///////////////////////////////////////////////////////////////////////////
218 // Reset all variables to 0
219 // The max. number of tracks is set to the initial value again
223 Double_t a[4]={0,0,0,0};
225 if (fNtinit > 0) SetNtinit(fNtinit);
227 ///////////////////////////////////////////////////////////////////////////
228 void AliJet::AddTrack(AliTrack& t)
230 // Add a track to the jet.
231 // In case the maximum number of tracks has been reached
232 // space will be extended to hold an additional amount of tracks as
233 // was initially reserved.
234 // See SetTrackCopy() to tailor the functionality of the stored structures.
237 // In case a private copy is made, this is performed via the Clone() memberfunction.
238 // All AliTrack and derived classes have the default TObject::Clone() memberfunction.
239 // However, derived classes generally contain an internal data structure which may
240 // include pointers to other objects. Therefore it is recommended to provide
241 // for all derived classes a specific copy constructor and override the default Clone()
242 // memberfunction using this copy constructor.
243 // An example for this may be seen from AliTrack.
247 ///////////////////////////////////////////////////////////////////////////
248 void AliJet::AddTrack(AliTrack& t,Int_t copy)
250 // Internal memberfunction to actually add a track to the jet.
251 // In case the maximum number of tracks has been reached
252 // space will be extended to hold an additional amount of tracks as
253 // was initially reserved.
255 // If copy=0 NO copy of the track will be made, irrespective of the setting
256 // of the TrackCopy flag.
257 // This allows a proper treatment of automatically generated connecting
258 // tracks between vertices.
261 // In case a private copy is made, this is performed via the Clone() memberfunction.
265 fTracks=new TObjArray(fNtmax);
266 if (fTrackCopy) fTracks->SetOwner();
268 if (fNtrk == fNtmax) // Check if maximum track number is reached
271 fTracks->Expand(fNtmax);
274 // Add the track to this jet
276 if (fTrackCopy && copy)
278 fTracks->Add(t.Clone());
285 (*this)+=(Ali4Vector&)t;
289 ///////////////////////////////////////////////////////////////////////////
290 void AliJet::Data(TString f)
292 // Provide jet information within the coordinate frame f
293 const char* name=GetName();
294 const char* title=GetTitle();
296 cout << " *AliJet::Data*";
297 if (strlen(name)) cout << " Name : " << GetName();
298 if (strlen(title)) cout << " Title : " << GetTitle();
300 cout << " Id : " << fUserId << " Invmass : " << GetInvmass() << " Charge : " << fQ
301 << " Momentum : " << GetMomentum() << " Ntracks : " << fNtrk << endl;
305 ///////////////////////////////////////////////////////////////////////////
306 void AliJet::List(TString f)
308 // Provide jet and primary track information within the coordinate frame f
310 Data(f); // Information of the current jet
312 // The tracks of this jet
314 for (Int_t it=1; it<=fNtrk; it++)
319 cout << " ---Track no. " << it << endl;
325 cout << " *AliJet::List* Error : No track present." << endl;
329 ///////////////////////////////////////////////////////////////////////////
330 void AliJet::ListAll(TString f)
332 // Provide jet and prim.+sec. track information within the coordinate frame f
334 Data(f); // Information of the current jet
336 // The tracks of this jet
338 for (Int_t it=1; it<=fNtrk; it++)
343 cout << " ---Track no. " << it << endl;
349 cout << " *AliJet::List* Error : No track present." << endl;
353 ///////////////////////////////////////////////////////////////////////////
354 Int_t AliJet::GetNtracks() const
356 // Return the current number of tracks of this jet
359 ///////////////////////////////////////////////////////////////////////////
360 Double_t AliJet::GetEnergy()
362 // Return the total energy of the jet
365 ///////////////////////////////////////////////////////////////////////////
366 Double_t AliJet::GetMomentum()
368 // Return the value of the total jet 3-momentum
369 // The error can be obtained by invoking GetResultError() after
370 // invokation of GetMomentum().
371 Double_t norm=fV.GetNorm();
372 fDresult=fV.GetResultError();
375 ///////////////////////////////////////////////////////////////////////////
376 Ali3Vector AliJet::Get3Momentum() const
378 // Return the the total jet 3-momentum
379 Ali3Vector p=Get3Vector();
382 ///////////////////////////////////////////////////////////////////////////
383 Double_t AliJet::GetInvmass()
385 // Return the invariant mass of the jet
386 Double_t m2=Dot(*this);
396 ///////////////////////////////////////////////////////////////////////////
397 Float_t AliJet::GetCharge() const
399 // Return the total charge of the jet
402 ///////////////////////////////////////////////////////////////////////////
403 AliTrack* AliJet::GetTrack(Int_t i) const
405 // Return the i-th track of this jet
408 cout << " *AliJet*::GetTrack* No tracks present." << endl;
415 cout << " *AliJet*::GetTrack* Invalid argument i : " << i
416 << " Ntrk = " << fNtrk << endl;
421 return (AliTrack*)fTracks->At(i-1);
425 ///////////////////////////////////////////////////////////////////////////
426 AliTrack* AliJet::GetIdTrack(Int_t id) const
428 // Return the track with user identifier "id" of this jet
433 cout << " *AliJet*::GetIdTrack* No tracks present." << endl;
438 for (Int_t i=0; i<fNtrk; i++)
440 tx=(AliTrack*)fTracks->At(i);
441 if (id == tx->GetId()) t=tx;
446 ///////////////////////////////////////////////////////////////////////////
447 Double_t AliJet::GetPt()
449 // Provide trans. momentum value w.r.t. z-axis.
450 // The error on the value can be obtained by GetResultError()
451 // after invokation of GetPt().
454 Double_t norm=v.GetNorm();
455 fDresult=v.GetResultError();
459 ///////////////////////////////////////////////////////////////////////////
460 Double_t AliJet::GetPl()
462 // Provide long. momentum value w.r.t. z-axis.
463 // Note : the returned value can also be negative.
464 // The error on the value can be obtained by GetResultError()
465 // after invokation of GetPl().
469 Double_t pl=v.GetNorm();
470 fDresult=v.GetResultError();
473 v.GetVector(a,"sph");
474 if (cos(a[1])<0) pl=-pl;
478 ///////////////////////////////////////////////////////////////////////////
479 Double_t AliJet::GetEt()
481 // Provide trans. energy value w.r.t. z-axis.
482 // The error on the value can be obtained by GetResultError()
483 // after invokation of GetEt().
484 Double_t et=GetScaTrans();
488 ///////////////////////////////////////////////////////////////////////////
489 Double_t AliJet::GetEl()
491 // Provide long. energy value w.r.t. z-axis.
492 // Note : the returned value can also be negative.
493 // The error on the value can be obtained by GetResultError()
494 // after invokation of GetEl().
495 Double_t el=GetScaLong();
499 ///////////////////////////////////////////////////////////////////////////
500 Double_t AliJet::GetMt()
502 // Provide transverse mass value w.r.t. z-axis.
503 // The error on the value can be obtained by GetResultError()
504 // after invokation of GetMt().
506 Double_t dpt=GetResultError();
507 Double_t m=GetInvmass();
508 Double_t dm=GetResultError();
510 Double_t mt=sqrt(pt*pt+m*m);
512 if (mt) dmt2=(pow((pt*dpt),2)+pow((m*dm),2))/(mt*mt);
517 ///////////////////////////////////////////////////////////////////////////
518 Double_t AliJet::GetRapidity()
520 // Provide rapidity value w.r.t. z-axis.
521 // The error on the value can be obtained by GetResultError()
522 // after invokation of GetRapidity().
523 // Note : Also GetPseudoRapidity() is available since this class is
524 // derived from Ali4Vector.
525 Double_t e=GetEnergy();
526 Double_t de=GetResultError();
528 Double_t dpl=GetResultError();
532 Double_t y=9999,dy2=0;
533 if (sum && dif) y=0.5*log(sum/dif);
535 if (sum*dif) dy2=(1./(sum*dif))*(pow((pl*de),2)+pow((e*dpl),2));
540 ///////////////////////////////////////////////////////////////////////////
541 void AliJet::SetTrackCopy(Int_t j)
543 // (De)activate the creation of private copies of the added tracks.
544 // j=0 ==> No private copies are made; pointers of original tracks are stored.
545 // j=1 ==> Private copies of the tracks are made and these pointers are stored.
547 // Note : Once the storage contains pointer(s) to AliTrack(s) one cannot
548 // change the TrackCopy mode anymore.
549 // To change the TrackCopy mode for an existing AliJet containing
550 // tracks one first has to invoke Reset().
559 cout << "*AliJet::SetTrackCopy* Invalid argument : " << j << endl;
564 cout << "*AliJet::SetTrackCopy* Storage already contained tracks."
565 << " ==> TrackCopy mode not changed." << endl;
568 ///////////////////////////////////////////////////////////////////////////
569 Int_t AliJet::GetTrackCopy() const
571 // Provide value of the TrackCopy mode.
572 // 0 ==> No private copies are made; pointers of original tracks are stored.
573 // 1 ==> Private copies of the tracks are made and these pointers are stored.
576 ///////////////////////////////////////////////////////////////////////////
577 void AliJet::SetId(Int_t id)
579 // Set a user defined identifier for this jet.
582 ///////////////////////////////////////////////////////////////////////////
583 Int_t AliJet::GetId() const
585 // Provide the user defined identifier of this jet.
588 ///////////////////////////////////////////////////////////////////////////
589 TObject* AliJet::Clone(const char* name) const
591 // Make a deep copy of the current object and provide the pointer to the copy.
592 // This memberfunction enables automatic creation of new objects of the
593 // correct type depending on the object type, a feature which may be very useful
594 // for containers when adding objects in case the container owns the objects.
595 // This feature allows e.g. AliVertex to store either AliJet objects or
596 // objects derived from AliJet via the AddJet memberfunction, provided
597 // these derived classes also have a proper Clone memberfunction.
599 AliJet* jet=new AliJet(*this);
602 if (strlen(name)) jet->SetName(name);
606 ///////////////////////////////////////////////////////////////////////////