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 : By default all quantities are in GeV, GeV/c or GeV/c**2
88 // but the user can indicate the usage of a different scale
89 // for the energy-momentum units via the SetEscale() memberfunction.
90 // The actual energy-momentum unit scale can be obtained via the
91 // GetEscale() memberfunction.
93 //--- Author: Nick van Eijndhoven 10-jul-1997 UU-SAP Utrecht
94 //- Modified: NvE $Date$ UU-SAP Utrecht
95 ///////////////////////////////////////////////////////////////////////////
99 #include "Riostream.h"
100 #include "TObjArray.h"
103 #include "AliPositionObj.h"
104 #include "AliSignal.h"
106 ClassImp(AliJet) // Class implementation to enable ROOT I/O
108 AliJet::AliJet() : TNamed(),Ali4Vector()
110 // Default constructor
111 // All variables initialised to 0
112 // Initial maximum number of tracks is set to the default value
117 ///////////////////////////////////////////////////////////////////////////
120 // Initialisation of pointers etc...
128 ///////////////////////////////////////////////////////////////////////////
129 AliJet::AliJet(Int_t n) : TNamed(),Ali4Vector()
131 // Create a jet to hold initially a maximum of n tracks
132 // All variables initialised to 0
142 cout << " *AliJet* Initial max. number of tracks entered : " << n << endl;
143 cout << " This is invalid. Default initial maximum will be used." << endl;
148 ///////////////////////////////////////////////////////////////////////////
151 // Default destructor
168 ///////////////////////////////////////////////////////////////////////////
169 void AliJet::SetOwner(Bool_t own)
171 // Set ownership of all added objects.
172 // The default parameter is own=kTRUE.
174 // Invokation of this memberfunction also sets all the copy modes
175 // (e.g. TrackCopy & co.) according to the value of own.
177 // This function (with own=kTRUE) is particularly useful when reading data
178 // from a tree/file, since Reset() will then actually remove all the
179 // added objects from memory irrespective of the copy mode settings
180 // during the tree/file creation process. In this way it provides a nice way
181 // of preventing possible memory leaks in the reading/analysis process.
183 // In addition this memberfunction can also be used as a shortcut to set all
184 // copy modes in one go during a tree/file creation process.
185 // However, in this case the user has to take care to only set/change the
186 // ownership (and copy mode) for empty objects (e.g. newly created objects
187 // or after invokation of the Reset() memberfunction) otherwise it will
188 // very likely result in inconsistent destructor behaviour.
192 if (fTracks) fTracks->SetOwner(own);
195 ///////////////////////////////////////////////////////////////////////////
196 AliJet::AliJet(const AliJet& j) : TNamed(j),Ali4Vector(j)
204 fTrackCopy=j.fTrackCopy;
206 if (j.fRef) fRef=new AliPositionObj(*(j.fRef));
213 fTracks=new TObjArray(fNtmax);
214 if (fTrackCopy) fTracks->SetOwner();
217 for (Int_t i=1; i<=fNtrk; i++)
219 AliTrack* tx=j.GetTrack(i);
222 fTracks->Add(tx->Clone());
230 ///////////////////////////////////////////////////////////////////////////
231 void AliJet::SetNtinit(Int_t n)
233 // Set the initial maximum number of tracks for this jet
248 ///////////////////////////////////////////////////////////////////////////
251 // Reset all variables to 0
252 // The max. number of tracks is set to the initial value again
253 // Note : The scale for the energy/momentum units will not be changed.
257 Double_t a[4]={0,0,0,0};
259 if (fNtinit > 0) SetNtinit(fNtinit);
261 ///////////////////////////////////////////////////////////////////////////
262 void AliJet::AddTrack(AliTrack& t)
264 // Add a track to the jet.
265 // In case the maximum number of tracks has been reached
266 // space will be extended to hold an additional amount of tracks as
267 // was initially reserved.
268 // See SetTrackCopy() to tailor the functionality of the stored structures.
272 // In case a private copy is made, this is performed via the Clone() memberfunction.
273 // All AliTrack and derived classes have the default TObject::Clone() memberfunction.
274 // However, derived classes generally contain an internal data structure which may
275 // include pointers to other objects. Therefore it is recommended to provide
276 // for all derived classes a specific copy constructor and override the default Clone()
277 // memberfunction using this copy constructor.
278 // An example for this may be seen from AliTrack.
280 // In case NO private copy is made, a check will be performed if this
281 // specific track is already present in the jet.
282 // If this is the case, no action is performed to prevent multiple
283 // additions of the same track.
288 ///////////////////////////////////////////////////////////////////////////
289 void AliJet::AddTrack(AliTrack& t,Int_t copy)
291 // Internal memberfunction to actually add a track to the jet.
292 // In case the maximum number of tracks has been reached
293 // space will be extended to hold an additional amount of tracks as
294 // was initially reserved.
296 // If copy=0 NO copy of the track will be made, irrespective of the setting
297 // of the TrackCopy flag.
298 // This allows a proper treatment of automatically generated connecting
299 // tracks between vertices.
301 // In case NO copy of the track is made, a check will be performed if this
302 // specific track is already present in the jet.
303 // If this is the case, no action is performed to prevent multiple
304 // additions of the same track.
307 // In case a private copy is made, this is performed via the Clone() memberfunction.
311 fTracks=new TObjArray(fNtmax);
312 if (fTrackCopy) fTracks->SetOwner();
314 else if (!fTrackCopy || !copy) // Check if this track is already present
316 for (Int_t i=0; i<fNtrk; i++)
318 AliTrack* tx=(AliTrack*)fTracks->At(i);
319 if (tx == &t) return;
323 if (fNtrk == fNtmax) // Check if maximum track number is reached
326 fTracks->Expand(fNtmax);
329 // Add the track to this jet
331 if (fTrackCopy && copy)
333 fTracks->Add(t.Clone());
342 Ali4Vector p4=(Ali4Vector)t;
343 Float_t tscale=t.GetEscale();
344 if ((tscale/fEscale > 1.1) || (fEscale/tscale > 1.1)) p4=p4*(tscale/fEscale);
348 ///////////////////////////////////////////////////////////////////////////
349 void AliJet::Data(TString f,TString u)
351 // Provide jet information within the coordinate frame f
353 // The string argument "u" allows to choose between different angular units
354 // in case e.g. a spherical frame is selected.
355 // u = "rad" : angles provided in radians
356 // "deg" : angles provided in degrees
358 // The defaults are f="car" and u="rad".
360 const char* name=GetName();
361 const char* title=GetTitle();
363 cout << " *AliJet::Data*";
364 if (strlen(name)) cout << " Name : " << GetName();
365 if (strlen(title)) cout << " Title : " << GetTitle();
367 cout << " Id : " << fUserId << " Invmass : " << GetInvmass() << " Charge : " << fQ
368 << " Momentum : " << GetMomentum() << " Energy scale : " << fEscale << " GeV" << endl;
372 Ali4Vector::Data(f,u);
374 ///////////////////////////////////////////////////////////////////////////
375 void AliJet::List(TString f,TString u)
377 // Provide jet and primary track information within the coordinate frame f
379 // The string argument "u" allows to choose between different angular units
380 // in case e.g. a spherical frame is selected.
381 // u = "rad" : angles provided in radians
382 // "deg" : angles provided in degrees
384 // The defaults are f="car" and u="rad".
386 Data(f,u); // Information of the current jet
387 if (fRef) { cout << " Ref-point :"; fRef->Data(f,u); }
389 // The tracks of this jet
391 for (Int_t it=1; it<=fNtrk; it++)
396 cout << " ---Track no. " << it << endl;
402 cout << " *AliJet::List* Error : No track present." << endl;
406 ///////////////////////////////////////////////////////////////////////////
407 void AliJet::ListAll(TString f,TString u)
409 // Provide jet and prim.+sec. track information within the coordinate frame f
411 // The string argument "u" allows to choose between different angular units
412 // in case e.g. a spherical frame is selected.
413 // u = "rad" : angles provided in radians
414 // "deg" : angles provided in degrees
416 // The defaults are f="car" and u="rad".
418 Data(f,u); // Information of the current jet
419 if (fRef) { cout << " Ref-point :"; fRef->Data(f,u); }
421 // The tracks of this jet
423 for (Int_t it=1; it<=fNtrk; it++)
428 cout << " ---Track no. " << it << endl;
434 cout << " *AliJet::List* Error : No track present." << endl;
438 ///////////////////////////////////////////////////////////////////////////
439 Int_t AliJet::GetNtracks(Int_t idmode,Int_t chmode,Int_t pcode)
441 // Provide the number of user selected tracks in this jet based on the
442 // idmode, chmode and pcode selections as specified by the user.
443 // For specification of the selection parameters see GetTracks().
444 // The default parameters correspond to no selection, which implies
445 // that invokation of GetNtracks() just returns the total number of
446 // tracks registered in this jet.
448 // Note : In case certain selections are specified, this function
449 // invokes GetTracks(idmode,chmode,pcode) to determine the
450 // number of tracks corresponding to the selections.
451 // When the jet contains a large number of tracks, invokation
452 // of GetTracks(idmode,chmode,pcode) and subsequently invoking
453 // GetEntries() for the resulting TObjArray* might be slightly
457 if (idmode==0 && chmode==2 && pcode==0)
463 TObjArray* arr=GetTracks(idmode,chmode,pcode);
464 if (arr) n=arr->GetEntries();
468 ///////////////////////////////////////////////////////////////////////////
469 Int_t AliJet::GetNtracks(TString name)
471 // Provide the number of tracks with the specified name.
475 // This facility invokes the corresponding GetTracks memberfunction
476 // and as such may result in overwriting existing track selection
477 // arrays. Please refer to the docs of GetTracks for further details.
481 TObjArray* arr=GetTracks(name);
482 if (arr) n=arr->GetEntries();
485 ///////////////////////////////////////////////////////////////////////////
486 Double_t AliJet::GetEnergy(Float_t scale)
488 // Return the total energy of the jet.
489 // By default the energy is returned in the units as it was stored in the jet
490 // structure. However, the user can select a different energy unit scale by
491 // specification of the scale parameter.
492 // The convention is that scale=1 corresponds to GeV, so specification
493 // of scale=0.001 will provide the energy in MeV.
494 // The error can be obtained by invoking GetResultError() after
495 // invokation of GetEnergy().
496 Double_t E=GetScalar();
502 fDresult*=fEscale/scale;
511 ///////////////////////////////////////////////////////////////////////////
512 Double_t AliJet::GetMomentum(Float_t scale)
514 // Return the value of the total jet 3-momentum
515 // By default the momentum is returned in the units as it was stored in the jet
516 // structure. However, the user can select a different momentum unit scale by
517 // specification of the scale parameter.
518 // The convention is that scale=1 corresponds to GeV/c, so specification
519 // of scale=0.001 will provide the momentum in MeV/c.
520 // The error can be obtained by invoking GetResultError() after
521 // invokation of GetMomentum().
523 Double_t norm=fV.GetNorm();
524 fDresult=fV.GetResultError();
528 fDresult*=fEscale/scale;
532 ///////////////////////////////////////////////////////////////////////////
533 Ali3Vector AliJet::Get3Momentum(Float_t scale) const
535 // Return the the total jet 3-momentum
536 // By default the components of the 3-momentum are returned in the units
537 // as they were stored in the jet structure.
538 // However, the user can select a different momentum unit scale for the
539 // components by specification of the scale parameter.
540 // The convention is that scale=1 corresponds to GeV/c, so specification
541 // of scale=0.001 will provide the 3-momentum in MeV/c.
543 Ali3Vector p=Get3Vector();
544 if (scale>0) p*=fEscale/scale;
547 ///////////////////////////////////////////////////////////////////////////
548 Double_t AliJet::GetInvmass(Float_t scale)
550 // Return the invariant mass of the jet.
551 // By default the mass is returned in the units as it was stored in the jet
552 // structure. However, the user can select a different mass unit scale by
553 // specification of the scale parameter.
554 // The convention is that scale=1 corresponds to GeV/c**2, so specification
555 // of scale=0.001 will provide the invariant mass in MeV/c**2.
556 // The error can be obtained by invoking GetResultError() after
557 // invokation of GetInvmass().
559 Double_t inv=Dot(*this);
560 Double_t dinv=GetResultError();
564 Double_t m=sqrt(inv);
565 if (m) dm=dinv/(2.*m);
580 ///////////////////////////////////////////////////////////////////////////
581 Float_t AliJet::GetCharge() const
583 // Return the total charge of the jet
586 ///////////////////////////////////////////////////////////////////////////
587 AliTrack* AliJet::GetTrack(Int_t i) const
589 // Return the i-th track of this jet
591 if (!fTracks) return 0;
595 cout << " *AliJet*::GetTrack* Invalid argument i : " << i
596 << " Ntrk = " << fNtrk << endl;
601 return (AliTrack*)fTracks->At(i-1);
604 ///////////////////////////////////////////////////////////////////////////
605 AliTrack* AliJet::GetIdTrack(Int_t id) const
607 // Return the track with user identifier "id" of this jet
608 if (!fTracks) return 0;
611 for (Int_t i=0; i<fNtrk; i++)
613 tx=(AliTrack*)fTracks->At(i);
614 if (id == tx->GetId()) return tx;
616 return 0; // No matching id found
618 ///////////////////////////////////////////////////////////////////////////
619 TObjArray* AliJet::GetTracks(Int_t idmode,Int_t chmode,Int_t pcode)
621 // Provide references to user selected tracks based on the idmode, chmode
622 // and pcode selections as specified by the user.
624 // The following selection combinations are available :
625 // ----------------------------------------------------
626 // idmode = -1 ==> Select tracks with negative user identifier "id"
627 // 0 ==> No selection on user identifier
628 // 1 ==> Select tracks with positive user identifier "id"
630 // chmode = -1 ==> Select tracks with negative charge
631 // 0 ==> Select neutral tracks
632 // 1 ==> Select tracks with positive charge
633 // 2 ==> No selection on charge
634 // 3 ==> Select all charged tracks
636 // pcode = 0 ==> No selection on particle code
637 // X ==> Select tracks with particle code +X or -X
638 // This allows selection of both particles and anti-particles
639 // in case of PDG particle codes.
640 // Selection of either particles or anti-particles can be
641 // obtained in combination with the "chmode" selector.
645 // idmode=-1 chmode=0 pcode=0 : Selection of all neutral tracks with negative id.
646 // idmode=0 chmode=2 pcode=211 : Selection of all charged pions (PDG convention).
647 // idmode=0 chmode=1 pcode=321 : Selection of all positive kaons (PDG convention).
649 // The default values are idmode=0 chmode=2 pcode=0 (i.e. no selections applied).
653 // 1) In case the user has labeled simulated tracks with negative id and
654 // reconstructed tracks with positive id, this memberfunction provides
655 // easy access to either all simulated or reconstructed tracks.
656 // 2) Subsequent invokations of this memberfunction with e.g. chmode=-1 and chmode=1
657 // provides a convenient way to investigate particle pairs with opposite charge
658 // (e.g. for invariant mass analysis).
659 // 3) The selected track pointers are returned via a multi-purpose array,
660 // which will be overwritten by subsequent selections.
661 // In case the selected track list is to be used amongst other selections,
662 // the user is advised to store the selected track pointers in a local
663 // TObjArray or TRefArray.
671 fSelected=new TObjArray();
674 if (!fTracks) return fSelected;
680 for (Int_t i=0; i<fNtrk; i++)
682 tx=(AliTrack*)fTracks->At(i);
685 code=tx->GetParticleCode();
686 if (pcode && abs(pcode)!=abs(code)) continue;
689 if (idmode==-1 && id>=0) continue;
690 if (idmode==1 && id<=0) continue;
693 if (chmode==-1 && q>=0) continue;
694 if (chmode==0 && fabs(q)>1e-10) continue;
695 if (chmode==1 && q<=0) continue;
696 if (chmode==3 && fabs(q)<1e-10) continue;
703 ///////////////////////////////////////////////////////////////////////////
704 TObjArray* AliJet::GetTracks(TString name)
706 // Provide references to all tracks with the specified name.
710 // 1) In case the user has labeled reconstructed tracks with the name of
711 // the applied reconstruction algorithm, this memberfunction provides
712 // easy access to all tracks reconstructed by a certain method.
713 // 2) The selected track pointers are returned via a multi-purpose array,
714 // which will be overwritten by subsequent selections.
715 // In case the selected track list is to be used amongst other selections,
716 // the user is advised to store the selected track pointers in a local
717 // TObjArray or TRefArray.
725 fSelected=new TObjArray();
728 if (!fTracks) return fSelected;
732 for (Int_t i=0; i<fNtrk; i++)
734 tx=(AliTrack*)fTracks->At(i);
738 if (s == name) fSelected->Add(tx);
743 ///////////////////////////////////////////////////////////////////////////
744 void AliJet::RemoveTracks(TString name)
746 // Remove all tracks with the specified name.
747 // If name="*" all tracks will be removed.
751 // In case the user has labeled reconstructed tracks with the name of
752 // the applied reconstruction algorithm, this memberfunction provides
753 // easy removal of all tracks reconstructed by a certain method.
755 if (!fTracks) return;
760 for (Int_t i=0; i<fNtrk; i++)
762 tx=(AliTrack*)fTracks->At(i);
766 if (s==name || name=="*")
768 obj=fTracks->Remove(tx);
769 if (obj && fTracks->IsOwner()) delete tx;
773 fNtrk=fTracks->GetEntries();
775 ///////////////////////////////////////////////////////////////////////////
776 void AliJet::RemoveTracks(Int_t idmode,Int_t chmode,Int_t pcode)
778 // Remove user selected tracks based on the idmode, chmode and pcode
779 // selections as specified by the user.
780 // For defintions of these selections see the corresponding GetTracks()
783 if (!fTracks) return;
785 TObjArray* arr=GetTracks(idmode,chmode,pcode);
788 Int_t ntk=arr->GetEntries();
793 for (Int_t i=0; i<ntk; i++)
795 tx=(AliTrack*)arr->At(i);
798 obj=fTracks->Remove(tx);
799 if (obj && fTracks->IsOwner()) delete tx;
802 fNtrk=fTracks->GetEntries();
805 ///////////////////////////////////////////////////////////////////////////
806 void AliJet::ShowTracks(Int_t mode)
808 // Provide an overview of the available tracks.
809 // The argument mode determines the amount of information as follows :
810 // mode = 0 ==> Only printout of the number of tracks
811 // 1 ==> Provide a listing with 1 line of info for each track
813 // The default is mode=1.
815 Int_t ntk=GetNtracks();
820 cout << " There are " << ntk << " tracks available." << endl;
824 cout << " The following " << ntk << " tracks are available :" << endl;
825 for (Int_t i=1; i<=ntk; i++)
827 AliTrack* tx=GetTrack(i);
830 const char* name=tx->GetName();
831 const char* title=tx->GetTitle();
832 cout << " Track : " << i;
833 cout << " Id : " << tx->GetId();
834 cout << " Q : " << tx->GetCharge() << " m : " << tx->GetMass() << " p : " << tx->GetMomentum();
835 if (strlen(name)) cout << " Name : " << name;
836 if (strlen(title)) cout << " Title : " << title;
844 cout << " No tracks are present." << endl;
847 ///////////////////////////////////////////////////////////////////////////
848 Double_t AliJet::GetPt(Float_t scale)
850 // Provide the transverse momentum value w.r.t. z-axis.
851 // By default the value is returned in the units as it was stored in the jet
852 // structure. However, the user can select a different momentum unit scale by
853 // specification of the scale parameter.
854 // The convention is that scale=1 corresponds to GeV/c, so specification
855 // of scale=0.001 will provide the transverse momentum in MeV/c.
856 // The error on the value can be obtained by GetResultError()
857 // after invokation of GetPt().
860 Double_t norm=v.GetNorm();
861 fDresult=v.GetResultError();
865 fDresult*=fEscale/scale;
870 ///////////////////////////////////////////////////////////////////////////
871 Double_t AliJet::GetPl(Float_t scale)
873 // Provide the longitudinal momentum value w.r.t. z-axis.
874 // By default the value is returned in the units as it was stored in the jet
875 // structure. However, the user can select a different momentum unit scale by
876 // specification of the scale parameter.
877 // The convention is that scale=1 corresponds to GeV/c, so specification
878 // of scale=0.001 will provide the longitudinal momentum in MeV/c.
879 // Note : the returned value can also be negative.
880 // The error on the value can be obtained by GetResultError()
881 // after invokation of GetPl().
886 Double_t pl=v.GetNorm();
887 fDresult=v.GetResultError();
890 v.GetVector(a,"sph");
891 if (cos(a[1])<0) pl=-pl;
895 fDresult*=fEscale/scale;
900 ///////////////////////////////////////////////////////////////////////////
901 Double_t AliJet::GetEt(Float_t scale)
903 // Provide transverse energy value w.r.t. z-axis.
904 // By default the value is returned in the units as it was stored in the jet
905 // structure. However, the user can select a different energy unit scale by
906 // specification of the scale parameter.
907 // The convention is that scale=1 corresponds to GeV, so specification
908 // of scale=0.001 will provide the transverse energy in MeV.
909 // The error on the value can be obtained by GetResultError()
910 // after invokation of GetEt().
912 Double_t et=GetScaTrans();
916 fDresult*=fEscale/scale;
921 ///////////////////////////////////////////////////////////////////////////
922 Double_t AliJet::GetEl(Float_t scale)
924 // Provide longitudinal energy value w.r.t. z-axis.
925 // By default the value is returned in the units as it was stored in the jet
926 // structure. However, the user can select a different energy unit scale by
927 // specification of the scale parameter.
928 // The convention is that scale=1 corresponds to GeV, so specification
929 // of scale=0.001 will provide the longitudinal energy in MeV.
930 // Note : the returned value can also be negative.
931 // The error on the value can be obtained by GetResultError()
932 // after invokation of GetEl().
934 Double_t el=GetScaLong();
938 fDresult*=fEscale/scale;
943 ///////////////////////////////////////////////////////////////////////////
944 Double_t AliJet::GetMt(Float_t scale)
946 // Provide transverse mass value w.r.t. z-axis.
947 // By default the value is returned in the units as it was stored in the jet
948 // structure. However, the user can select a different energy unit scale by
949 // specification of the scale parameter.
950 // The convention is that scale=1 corresponds to GeV, so specification
951 // of scale=0.001 will provide the transverse mass in MeV.
952 // The error on the value can be obtained by GetResultError()
953 // after invokation of GetMt().
955 Double_t dpt=GetResultError();
956 Double_t m=GetInvmass();
957 Double_t dm=GetResultError();
959 Double_t mt=sqrt(pt*pt+m*m);
961 if (mt) dmt2=(pow((pt*dpt),2)+pow((m*dm),2))/(mt*mt);
967 fDresult*=fEscale/scale;
971 ///////////////////////////////////////////////////////////////////////////
972 Double_t AliJet::GetRapidity()
974 // Provide rapidity value w.r.t. z-axis.
975 // The error on the value can be obtained by GetResultError()
976 // after invokation of GetRapidity().
977 // Note : Also GetPseudoRapidity() is available since this class is
978 // derived from Ali4Vector.
979 Double_t e=GetEnergy();
980 Double_t de=GetResultError();
982 Double_t dpl=GetResultError();
986 Double_t y=9999,dy2=0;
987 if (sum && dif) y=0.5*log(sum/dif);
989 if (sum*dif) dy2=(1./(sum*dif))*(pow((pl*de),2)+pow((e*dpl),2));
994 ///////////////////////////////////////////////////////////////////////////
995 void AliJet::SetTrackCopy(Int_t j)
997 // (De)activate the creation of private copies of the added tracks.
998 // j=0 ==> No private copies are made; pointers of original tracks are stored.
999 // j=1 ==> Private copies of the tracks are made and these pointers are stored.
1001 // Note : Once the storage contains pointer(s) to AliTrack(s) one cannot
1002 // change the TrackCopy mode anymore.
1003 // To change the TrackCopy mode for an existing AliJet containing
1004 // tracks one first has to invoke Reset().
1013 cout << "*AliJet::SetTrackCopy* Invalid argument : " << j << endl;
1018 cout << "*AliJet::SetTrackCopy* Storage already contained tracks."
1019 << " ==> TrackCopy mode not changed." << endl;
1022 ///////////////////////////////////////////////////////////////////////////
1023 Int_t AliJet::GetTrackCopy() const
1025 // Provide value of the TrackCopy mode.
1026 // 0 ==> No private copies are made; pointers of original tracks are stored.
1027 // 1 ==> Private copies of the tracks are made and these pointers are stored.
1030 ///////////////////////////////////////////////////////////////////////////
1031 void AliJet::SetId(Int_t id)
1033 // Set a user defined identifier for this jet.
1036 ///////////////////////////////////////////////////////////////////////////
1037 Int_t AliJet::GetId() const
1039 // Provide the user defined identifier of this jet.
1042 ///////////////////////////////////////////////////////////////////////////
1043 void AliJet::SetReferencePoint(AliPosition& p)
1045 // Store the position of the jet reference-point.
1046 // The reference-point of a jet provides a means to define a generic
1047 // space-time location for the jet as a whole.
1048 // This doesn't have to be necessarily the location where all the constituent
1049 // tracks originate (e.g. a bundle of parallel tracks doesn't have such
1050 // a location). As such the meaning of this reference-point is different from
1051 // a normal vertex position and allows to provide complimentary information.
1052 // This reference point is the preferable point to start e.g. extrapolations
1053 // and investigate coincidences in space and/or time.
1054 if (fRef) delete fRef;
1055 fRef=new AliPositionObj(p);
1057 ///////////////////////////////////////////////////////////////////////////
1058 AliPosition* AliJet::GetReferencePoint()
1060 // Provide the position of the jet reference-point.
1061 // The reference-point of a jet provides a means to define a generic
1062 // space-time location for the jet as a whole.
1063 // This doesn't have to be necessarily the location where all the constituent
1064 // tracks originate (e.g. a bundle of parallel tracks doesn't have such
1065 // a location). As such the meaning of this reference-point is different from
1066 // a normal vertex position and allows to provide complimentary information.
1067 // This reference point is the preferable point to start e.g. extrapolations
1068 // and investigate coincidences in space and/or time.
1071 ///////////////////////////////////////////////////////////////////////////
1072 TObjArray* AliJet::SortTracks(Int_t mode,TObjArray* tracks)
1074 // Order the references to an array of tracks by looping over the input array "tracks"
1075 // and checking the value of a certain observable.
1076 // The ordered array is returned as a TObjArray.
1077 // In case tracks=0 (default), the registered tracks of the current jet are used.
1078 // Note that the original track array is not modified.
1079 // Via the "mode" argument the user can specify the observable to be checked upon
1080 // and specify whether sorting should be performed in decreasing order (mode<0)
1081 // or in increasing order (mode>0).
1083 // The convention for the observable selection is the following :
1084 // mode : 1 ==> Number of signals associated to the track
1085 // 2 ==> Track energy
1086 // 3 ==> Track momentum
1087 // 4 ==> Mass of the track
1088 // 5 ==> Transverse momentum of the track
1089 // 6 ==> Longitudinal momentum of the track
1090 // 7 ==> Transverse energy of the track
1091 // 8 ==> Longitudinal energy of the track
1092 // 9 ==> Transverse mass of the track
1093 // 10 ==> Track rapidity
1094 // 11 ==> Pseudo-rapidity of the track
1095 // 12 ==> Charge of the track
1096 // 13 ==> Probability of the track hypothesis
1098 // The default is mode=-1.
1100 // Note : This sorting routine uses a common area in memory, which is used
1101 // by various other sorting facilities as well.
1102 // This means that the resulting sorted TObjArray may be overwritten
1103 // when another sorting is invoked.
1104 // To retain the sorted list of pointers, the user is advised to copy
1105 // the pointers contained in the returned TObjArray into a private
1106 // TObjArray instance.
1114 if (!tracks) tracks=fTracks;
1116 if (!mode || abs(mode)>13 || !tracks) return fSelected;
1118 Int_t ntracks=tracks->GetEntries();
1125 fSelected=new TObjArray(ntracks);
1128 Double_t val1,val2; // Values of the observable to be tested upon
1131 for (Int_t i=0; i<ntracks; i++) // Loop over all tracks of the array
1133 AliTrack* tx=(AliTrack*)tracks->At(i);
1137 if (nord == 0) // store the first track at the first ordered position
1140 fSelected->AddAt(tx,nord-1);
1144 for (Int_t j=0; j<=nord; j++) // put track in the right ordered position
1146 if (j == nord) // track has smallest (mode<0) or largest (mode>0) observable value seen so far
1149 fSelected->AddAt(tx,j); // add track at the end
1150 break; // go for next track
1159 val1=tx->GetNsignals();
1160 val2=((AliTrack*)fSelected->At(j))->GetNsignals();
1163 val1=tx->GetEnergy(1);
1164 val2=((AliTrack*)fSelected->At(j))->GetEnergy(1);
1167 val1=tx->GetMomentum(1);
1168 val2=((AliTrack*)fSelected->At(j))->GetMomentum(1);
1171 val1=tx->GetMass(1);
1172 val2=((AliTrack*)fSelected->At(j))->GetMass(1);
1176 val2=((AliTrack*)fSelected->At(j))->GetPt(1);
1180 val2=((AliTrack*)fSelected->At(j))->GetPl(1);
1184 val2=((AliTrack*)fSelected->At(j))->GetEt(1);
1188 val2=((AliTrack*)fSelected->At(j))->GetEl(1);
1192 val2=((AliTrack*)fSelected->At(j))->GetMt(1);
1195 val1=tx->GetRapidity();
1196 val2=((AliTrack*)fSelected->At(j))->GetRapidity();
1199 val1=tx->GetPseudoRapidity();
1200 val2=((AliTrack*)fSelected->At(j))->GetPseudoRapidity();
1203 val1=tx->GetCharge();
1204 val2=((AliTrack*)fSelected->At(j))->GetCharge();
1208 val2=((AliTrack*)fSelected->At(j))->GetProb();
1212 if (mode<0 && val1 <= val2) continue;
1213 if (mode>0 && val1 >= val2) continue;
1216 for (Int_t k=nord-1; k>j; k--) // create empty position
1218 fSelected->AddAt(fSelected->At(k-1),k);
1220 fSelected->AddAt(tx,j); // put track at empty position
1221 break; // go for next track
1226 ///////////////////////////////////////////////////////////////////////////
1227 Double_t AliJet::GetDistance(AliPosition* p,Float_t scale)
1229 // Provide distance of the current jet to the position p.
1230 // The error on the result can be obtained as usual by invoking
1231 // GetResultError() afterwards.
1233 // By default the distance will be provided in the metric unit scale of
1234 // the AliPosition p.
1235 // However, the user can select a different metric unit scale by
1236 // specification of the scale parameter.
1237 // The convention is that scale=1 corresponds to meter, so specification
1238 // of scale=0.01 will provide the distance in cm.
1239 // As such it is possible to obtain a correctly computed distance even in case
1240 // the jet parameters have a different unit scale.
1241 // However, it is recommended to work always with one single unit scale.
1243 // Note : In case of incomplete information, a distance value of -1 is
1249 if (!p) return dist;
1251 // Obtain a defined position on this jet
1252 AliPosition* rx=fRef;
1254 if (!rx) return dist;
1256 Ali3Vector pj=Get3Momentum();
1258 if (pj.GetNorm() <= 0.) return dist;
1261 tj.Set3Momentum(pj);
1262 tj.SetReferencePoint(*rx);
1263 dist=tj.GetDistance(p,scale);
1264 fDresult=tj.GetResultError();
1267 ///////////////////////////////////////////////////////////////////////////
1268 Double_t AliJet::GetDistance(AliTrack* t,Float_t scale)
1270 // Provide distance of the current jet to the track t.
1271 // The error on the result can be obtained as usual by invoking
1272 // GetResultError() afterwards.
1274 // By default the distance will be provided in the metric unit scale of
1276 // However, the user can specify a required metric unit scale by specification
1277 // of the scale parameter.
1278 // The convention is that scale=1 corresponds to meter, so specification
1279 // of scale=0.01 will provide the distance in cm.
1280 // As such it is possible to obtain a correctly computed distance even in case
1281 // the jet and track parameters have a different unit scale.
1282 // However, it is recommended to work always with one single unit scale.
1284 // Note : In case of incomplete information, a distance value of -1 is
1290 if (!t) return dist;
1292 // Obtain a defined position on this jet
1293 AliPosition* rx=fRef;
1295 if (!rx) return dist;
1297 Ali3Vector pj=Get3Momentum();
1299 if (pj.GetNorm() <= 0.) return dist;
1302 tj.Set3Momentum(pj);
1303 tj.SetReferencePoint(*rx);
1304 dist=tj.GetDistance(t,scale);
1305 fDresult=tj.GetResultError();
1308 ///////////////////////////////////////////////////////////////////////////
1309 Double_t AliJet::GetDistance(AliJet* j,Float_t scale)
1311 // Provide distance of the current jet to the jet j.
1312 // The error on the result can be obtained as usual by invoking
1313 // GetResultError() afterwards.
1315 // By default the distance will be provided in the metric unit scale of
1317 // This implies that the results of j1.GetDistance(j2) and j2.GetDistance(j1)
1318 // may be numerically different in case j1 and j2 have different metric units.
1319 // However, the user can specify a required metric unit scale by specification
1320 // of the scale parameter.
1321 // The convention is that scale=1 corresponds to meter, so specification
1322 // of scale=0.01 will provide the distance in cm.
1323 // As such it is possible to obtain a correctly computed distance even in case
1324 // the jet parameters have a different unit scale.
1325 // However, it is recommended to work always with one single unit scale.
1327 // Note : In case of incomplete information, a distance value of -1 is
1333 if (!j) return dist;
1335 // Obtain a defined position on jet j
1336 AliPosition* rx=j->GetReferencePoint();
1338 if (!rx) return dist;
1340 Ali3Vector pj=j->Get3Momentum();
1342 if (pj.GetNorm() <= 0.) return dist;
1345 tj.Set3Momentum(pj);
1346 tj.SetReferencePoint(*rx);
1347 dist=GetDistance(tj,scale);
1350 ///////////////////////////////////////////////////////////////////////////
1351 Int_t AliJet::GetNsignals() const
1353 // Provide the number of signals associated to the jet tracks.
1354 // Note : Multiple occurrences of the same signal are only counted once.
1356 if (fNtrk<1) return 0;
1363 for (Int_t i=1; i<=fNtrk; i++)
1366 for (Int_t j=1; j<=tx->GetNsignals(); j++)
1368 AliSignal* sx=tx->GetSignal(j);
1371 for (Int_t k=0; k<arr.GetEntries(); k++)
1373 if (sx==(AliSignal*)arr.At(k))
1379 if (!exists) arr.Add(sx);
1385 ///////////////////////////////////////////////////////////////////////////
1386 void AliJet::SetEscale(Float_t scale)
1388 // Indicate the energy/momentum scale as used by the user.
1389 // The convention is that scale=1 indicates values in units
1390 // of GeV, GeV/c or GeV/c**2.
1391 // So, in case one decides to store values in units of MeV, MeV/c or MeV/c**2
1392 // the scale indicator should be set to scale=0.001.
1394 // By default scale=1 is set in the constructor.
1402 cout << " *AliJet::SetEscale* Invalid scale value : " << scale << endl;
1405 ///////////////////////////////////////////////////////////////////////////
1406 Float_t AliJet::GetEscale() const
1408 // Provide the energy/momentum scale as used by the user.
1409 // The convention is that scale=1 indicates values in units
1410 // of GeV, GeV/c or GeV/c**2.
1411 // So, a value of scale=0.001 indicates that energy/momentum values are
1412 // stored in units of MeV, MeV/c or MeV/c**2.
1415 ///////////////////////////////////////////////////////////////////////////
1416 TObject* AliJet::Clone(const char* name) const
1418 // Make a deep copy of the current object and provide the pointer to the copy.
1419 // This memberfunction enables automatic creation of new objects of the
1420 // correct type depending on the object type, a feature which may be very useful
1421 // for containers when adding objects in case the container owns the objects.
1422 // This feature allows e.g. AliVertex to store either AliJet objects or
1423 // objects derived from AliJet via the AddJet memberfunction, provided
1424 // these derived classes also have a proper Clone memberfunction.
1426 AliJet* jet=new AliJet(*this);
1429 if (strlen(name)) jet->SetName(name);
1433 ///////////////////////////////////////////////////////////////////////////