TLorentzVector is a legacy class. It is slower and worse for serialization than the recommended superior ROOT::Math::LorentzVector. ROOT provides specialisations of the ROOT::Math::LorentzVector template which are superior from the runtime performance offered, i.e.:
More details about the GenVector package can be found here.
TLorentzVector is a general four-vector class, which can be used either for the description of position and time (x,y,z,t) or momentum and energy (px,py,pz,E).
TLorentzVector has been implemented as a set a TVector3 and a Double_t variable. By default all components are initialized by zero.
For backward compatibility there are two constructors from an Double_t and Float_t C array.
There are two sets of access functions to the components of a LorentzVector: X(), Y(), Z(), T() and Px(), Py(), Pz() and E(). Both sets return the same values but the first set is more relevant for use where TLorentzVector describes a combination of position and time and the second set is more relevant where TLorentzVector describes momentum and energy:
The components of TLorentzVector can also accessed by index:
You can use the Vect() member function to get the vector component of TLorentzVector:
For setting components also two sets of member functions can be used:
To set more the one component by one call you can use the SetVect() function for the TVector3 part or SetXYZT(), SetPxPyPzE(). For convenience there is
also a SetXYZM():
There are a couple of member functions to get and set the TVector3 part of the parameters in spherical coordinate systems:
or get information about the r-coordinate in cylindrical systems:
for convenience there are two more set functions SetPtEtaPhiE(pt,eta,phi,e); and SetPtEtaPhiM(pt,eta,phi,m);
The TLorentzVector class provides operators to add, subtract or compare four-vectors:
The scalar product of two four-vectors is calculated with the (-,-,-,+) metric,
i.e. s = v1*v2 = t1*t2-x1*x2-y1*y2-z1*z2
The magnitude squared mag2 of a four-vector is therefore:
It mag2 is negative mag = -Sqrt(-mag*mag). The member functions are:
Since in case of momentum and energy the magnitude has the meaning of invariant mass TLorentzVector provides the more meaningful aliases M2() and M(); The member functions Beta() and Gamma() returns beta and gamma = 1/Sqrt(1-beta*beta).
A boost in a general direction can be parameterised with three parameters which can be taken as the components of a three vector b = (bx,by,bz). With x = (x,y,z) and gamma = 1/Sqrt(1-beta*beta) (beta being the module of vector b), an arbitrary active Lorentz boost transformation (from the rod frame to the original frame) can be written as:
The member function Boost() performs a boost transformation from the rod frame to the original frame. BoostVector() returns a TVector3 of the spatial components divided by the time component:
There are four sets of functions to rotate the TVector3 component of a TLorentzVector:
v.Rotate(TMath::Pi()/4., v1); // rotation around v1
Member functions Plus() and Minus() return the positive and negative light-cone components:
CAVEAT: The values returned are T{+,-}Z. It is known that some authors find it easier to define these components as (T{+,-}Z)/sqrt(2). Thus check what definition is used in the physics you're working in and adapt your code accordingly.
A general Lorentz transformation see class TLorentzRotation can be used by the Transform() member function, the *= or operator of the TLorentzRotation class:
Definition at line 32 of file TLorentzVector.h.
Public Types | |
enum | { kX =0 , kY =1 , kZ =2 , kT =3 , kNUM_COORDINATES =4 , kSIZE =kNUM_COORDINATES } |
typedef Double_t | Scalar |
Public Types inherited from TObject | |
enum | { kIsOnHeap = 0x01000000 , kNotDeleted = 0x02000000 , kZombie = 0x04000000 , kInconsistent = 0x08000000 , kBitMask = 0x00ffffff } |
enum | { kSingleKey = BIT(0) , kOverwrite = BIT(1) , kWriteDelete = BIT(2) } |
enum | EDeprecatedStatusBits { kObjInCanvas = BIT(3) } |
enum | EStatusBits { kCanDelete = BIT(0) , kMustCleanup = BIT(3) , kIsReferenced = BIT(4) , kHasUUID = BIT(5) , kCannotPick = BIT(6) , kNoContextMenu = BIT(8) , kInvalidObject = BIT(13) } |
Public Member Functions | |
TLorentzVector () | |
TLorentzVector (const Double_t *carray) | |
TLorentzVector (const Float_t *carray) | |
TLorentzVector (const TLorentzVector &lorentzvector) | |
TLorentzVector (const TVector3 &vector3, Double_t t) | |
TLorentzVector (Double_t x, Double_t y, Double_t z, Double_t t) | |
virtual | ~TLorentzVector () |
Double_t | Angle (const TVector3 &v) const |
Double_t | Beta () const |
void | Boost (const TVector3 &) |
void | Boost (Double_t, Double_t, Double_t) |
TVector3 | BoostVector () const |
Double_t | CosTheta () const |
Double_t | DeltaPhi (const TLorentzVector &) const |
Double_t | DeltaR (const TLorentzVector &) const |
Double_t | Dot (const TLorentzVector &) const |
Double_t | DrEtaPhi (const TLorentzVector &) const |
Double_t | E () const |
Double_t | Energy () const |
Double_t | Et () const |
Double_t | Et (const TVector3 &) const |
Double_t | Et2 () const |
Double_t | Et2 (const TVector3 &) const |
Double_t | Eta () const |
TVector2 | EtaPhiVector () |
Double_t | Gamma () const |
void | GetXYZT (Double_t *carray) const |
void | GetXYZT (Float_t *carray) const |
Double_t | M () const |
Double_t | M2 () const |
Double_t | Mag () const |
Double_t | Mag2 () const |
Double_t | Minus () const |
Double_t | Mt () const |
Double_t | Mt2 () const |
Bool_t | operator!= (const TLorentzVector &) const |
Double_t & | operator() (int i) |
Double_t | operator() (int i) const |
Double_t | operator* (const TLorentzVector &) const |
TLorentzVector | operator* (Double_t a) const |
TLorentzVector & | operator*= (const TLorentzRotation &) |
TLorentzVector & | operator*= (const TRotation &) |
TLorentzVector & | operator*= (Double_t a) |
TLorentzVector | operator+ (const TLorentzVector &) const |
TLorentzVector & | operator+= (const TLorentzVector &) |
TLorentzVector | operator- () const |
TLorentzVector | operator- (const TLorentzVector &) const |
TLorentzVector & | operator-= (const TLorentzVector &) |
TLorentzVector & | operator= (const TLorentzVector &) |
Bool_t | operator== (const TLorentzVector &) const |
Double_t & | operator[] (int i) |
Double_t | operator[] (int i) const |
Double_t | P () const |
Double_t | Perp () const |
Double_t | Perp (const TVector3 &v) const |
Double_t | Perp2 () const |
Double_t | Perp2 (const TVector3 &v) const |
Double_t | Phi () const |
Double_t | Plus () const |
virtual void | Print (Option_t *option="") const |
Print the TLorentz vector components as (x,y,z,t) and (P,eta,phi,E) representations. More... | |
Double_t | PseudoRapidity () const |
Double_t | Pt () const |
Double_t | Pt (const TVector3 &v) const |
Double_t | Px () const |
Double_t | Py () const |
Double_t | Pz () const |
Double_t | Rapidity () const |
Double_t | Rho () const |
void | Rotate (Double_t, const TVector3 &) |
void | RotateUz (const TVector3 &newUzVector) |
void | RotateX (Double_t angle) |
void | RotateY (Double_t angle) |
void | RotateZ (Double_t angle) |
void | SetE (Double_t a) |
void | SetPerp (Double_t) |
void | SetPhi (Double_t phi) |
void | SetPtEtaPhiE (Double_t pt, Double_t eta, Double_t phi, Double_t e) |
void | SetPtEtaPhiM (Double_t pt, Double_t eta, Double_t phi, Double_t m) |
void | SetPx (Double_t a) |
void | SetPxPyPzE (Double_t px, Double_t py, Double_t pz, Double_t e) |
void | SetPy (Double_t a) |
void | SetPz (Double_t a) |
void | SetRho (Double_t rho) |
void | SetT (Double_t a) |
void | SetTheta (Double_t theta) |
void | SetVect (const TVector3 &vect3) |
void | SetVectM (const TVector3 &spatial, Double_t mass) |
void | SetVectMag (const TVector3 &spatial, Double_t magnitude) |
void | SetX (Double_t a) |
void | SetXYZM (Double_t x, Double_t y, Double_t z, Double_t m) |
void | SetXYZT (Double_t x, Double_t y, Double_t z, Double_t t) |
void | SetY (Double_t a) |
void | SetZ (Double_t a) |
Double_t | T () const |
Double_t | Theta () const |
TLorentzVector & | Transform (const TLorentzRotation &) |
TLorentzVector & | Transform (const TRotation &) |
TVector3 | Vect () const |
Double_t | X () const |
Double_t | Y () const |
Double_t | Z () const |
Public Member Functions inherited from TObject | |
TObject () | |
TObject constructor. More... | |
TObject (const TObject &object) | |
TObject copy ctor. More... | |
virtual | ~TObject () |
TObject destructor. More... | |
void | AbstractMethod (const char *method) const |
Use this method to implement an "abstract" method that you don't want to leave purely abstract. More... | |
virtual void | AppendPad (Option_t *option="") |
Append graphics object to current pad. More... | |
virtual void | Browse (TBrowser *b) |
Browse object. May be overridden for another default action. More... | |
ULong_t | CheckedHash () |
Check and record whether this class has a consistent Hash/RecursiveRemove setup (*) and then return the regular Hash value for this object. More... | |
virtual const char * | ClassName () const |
Returns name of class to which the object belongs. More... | |
virtual void | Clear (Option_t *="") |
virtual TObject * | Clone (const char *newname="") const |
Make a clone of an object using the Streamer facility. More... | |
virtual Int_t | Compare (const TObject *obj) const |
Compare abstract method. More... | |
virtual void | Copy (TObject &object) const |
Copy this to obj. More... | |
virtual void | Delete (Option_t *option="") |
Delete this object. More... | |
virtual Int_t | DistancetoPrimitive (Int_t px, Int_t py) |
Computes distance from point (px,py) to the object. More... | |
virtual void | Draw (Option_t *option="") |
Default Draw method for all objects. More... | |
virtual void | DrawClass () const |
Draw class inheritance tree of the class to which this object belongs. More... | |
virtual TObject * | DrawClone (Option_t *option="") const |
Draw a clone of this object in the current selected pad for instance with: gROOT->SetSelectedPad(gPad) . More... | |
virtual void | Dump () const |
Dump contents of object on stdout. More... | |
virtual void | Error (const char *method, const char *msgfmt,...) const |
Issue error message. More... | |
virtual void | Execute (const char *method, const char *params, Int_t *error=0) |
Execute method on this object with the given parameter string, e.g. More... | |
virtual void | Execute (TMethod *method, TObjArray *params, Int_t *error=0) |
Execute method on this object with parameters stored in the TObjArray. More... | |
virtual void | ExecuteEvent (Int_t event, Int_t px, Int_t py) |
Execute action corresponding to an event at (px,py). More... | |
virtual void | Fatal (const char *method, const char *msgfmt,...) const |
Issue fatal error message. More... | |
virtual TObject * | FindObject (const char *name) const |
Must be redefined in derived classes. More... | |
virtual TObject * | FindObject (const TObject *obj) const |
Must be redefined in derived classes. More... | |
virtual Option_t * | GetDrawOption () const |
Get option used by the graphics system to draw this object. More... | |
virtual const char * | GetIconName () const |
Returns mime type name of object. More... | |
virtual const char * | GetName () const |
Returns name of object. More... | |
virtual char * | GetObjectInfo (Int_t px, Int_t py) const |
Returns string containing info about the object at position (px,py). More... | |
virtual Option_t * | GetOption () const |
virtual const char * | GetTitle () const |
Returns title of object. More... | |
virtual UInt_t | GetUniqueID () const |
Return the unique object id. More... | |
virtual Bool_t | HandleTimer (TTimer *timer) |
Execute action in response of a timer timing out. More... | |
virtual ULong_t | Hash () const |
Return hash value for this object. More... | |
Bool_t | HasInconsistentHash () const |
Return true is the type of this object is known to have an inconsistent setup for Hash and RecursiveRemove (i.e. More... | |
virtual void | Info (const char *method, const char *msgfmt,...) const |
Issue info message. More... | |
virtual Bool_t | InheritsFrom (const char *classname) const |
Returns kTRUE if object inherits from class "classname". More... | |
virtual Bool_t | InheritsFrom (const TClass *cl) const |
Returns kTRUE if object inherits from TClass cl. More... | |
virtual void | Inspect () const |
Dump contents of this object in a graphics canvas. More... | |
void | InvertBit (UInt_t f) |
virtual Bool_t | IsEqual (const TObject *obj) const |
Default equal comparison (objects are equal if they have the same address in memory). More... | |
virtual Bool_t | IsFolder () const |
Returns kTRUE in case object contains browsable objects (like containers or lists of other objects). More... | |
R__ALWAYS_INLINE Bool_t | IsOnHeap () const |
virtual Bool_t | IsSortable () const |
R__ALWAYS_INLINE Bool_t | IsZombie () const |
virtual void | ls (Option_t *option="") const |
The ls function lists the contents of a class on stdout. More... | |
void | MayNotUse (const char *method) const |
Use this method to signal that a method (defined in a base class) may not be called in a derived class (in principle against good design since a child class should not provide less functionality than its parent, however, sometimes it is necessary). More... | |
virtual Bool_t | Notify () |
This method must be overridden to handle object notification. More... | |
void | Obsolete (const char *method, const char *asOfVers, const char *removedFromVers) const |
Use this method to declare a method obsolete. More... | |
void | operator delete (void *ptr) |
Operator delete. More... | |
void | operator delete[] (void *ptr) |
Operator delete []. More... | |
void * | operator new (size_t sz) |
void * | operator new (size_t sz, void *vp) |
void * | operator new[] (size_t sz) |
void * | operator new[] (size_t sz, void *vp) |
TObject & | operator= (const TObject &rhs) |
TObject assignment operator. More... | |
virtual void | Paint (Option_t *option="") |
This method must be overridden if a class wants to paint itself. More... | |
virtual void | Pop () |
Pop on object drawn in a pad to the top of the display list. More... | |
virtual void | Print (Option_t *option="") const |
This method must be overridden when a class wants to print itself. More... | |
virtual Int_t | Read (const char *name) |
Read contents of object with specified name from the current directory. More... | |
virtual void | RecursiveRemove (TObject *obj) |
Recursively remove this object from a list. More... | |
void | ResetBit (UInt_t f) |
virtual void | SaveAs (const char *filename="", Option_t *option="") const |
Save this object in the file specified by filename. More... | |
virtual void | SavePrimitive (std::ostream &out, Option_t *option="") |
Save a primitive as a C++ statement(s) on output stream "out". More... | |
void | SetBit (UInt_t f) |
void | SetBit (UInt_t f, Bool_t set) |
Set or unset the user status bits as specified in f. More... | |
virtual void | SetDrawOption (Option_t *option="") |
Set drawing option for object. More... | |
virtual void | SetUniqueID (UInt_t uid) |
Set the unique object id. More... | |
virtual void | SysError (const char *method, const char *msgfmt,...) const |
Issue system error message. More... | |
R__ALWAYS_INLINE Bool_t | TestBit (UInt_t f) const |
Int_t | TestBits (UInt_t f) const |
virtual void | UseCurrentStyle () |
Set current style settings in this object This function is called when either TCanvas::UseCurrentStyle or TROOT::ForceStyle have been invoked. More... | |
virtual void | Warning (const char *method, const char *msgfmt,...) const |
Issue warning message. More... | |
virtual Int_t | Write (const char *name=0, Int_t option=0, Int_t bufsize=0) |
Write this object to the current directory. More... | |
virtual Int_t | Write (const char *name=0, Int_t option=0, Int_t bufsize=0) const |
Write this object to the current directory. More... | |
Private Attributes | |
Double_t | fE |
TVector3 | fP |
Additional Inherited Members | |
Static Public Member Functions inherited from TObject | |
static Long_t | GetDtorOnly () |
Return destructor only flag. More... | |
static Bool_t | GetObjectStat () |
Get status of object stat flag. More... | |
static void | SetDtorOnly (void *obj) |
Set destructor only flag. More... | |
static void | SetObjectStat (Bool_t stat) |
Turn on/off tracking of objects in the TObjectTable. More... | |
Protected Member Functions inherited from TObject | |
virtual void | DoError (int level, const char *location, const char *fmt, va_list va) const |
Interface to ErrorHandler (protected). More... | |
void | MakeZombie () |
#include <TLorentzVector.h>
typedef Double_t TLorentzVector::Scalar |
Definition at line 41 of file TLorentzVector.h.
anonymous enum |
Enumerator | |
---|---|
kX | |
kY | |
kZ | |
kT | |
kNUM_COORDINATES | |
kSIZE |
Definition at line 43 of file TLorentzVector.h.
|
inline |
Definition at line 593 of file TLorentzVector.h.
Definition at line 596 of file TLorentzVector.h.
|
inline |
Definition at line 599 of file TLorentzVector.h.
|
inline |
Definition at line 602 of file TLorentzVector.h.
Definition at line 605 of file TLorentzVector.h.
|
inline |
Definition at line 608 of file TLorentzVector.h.
|
inlinevirtual |
Definition at line 61 of file TLorentzVector.h.
Definition at line 478 of file TLorentzVector.h.
|
inline |
Definition at line 503 of file TLorentzVector.h.
Definition at line 551 of file TLorentzVector.h.
Definition at line 265 of file TLorentzVector.cxx.
|
inline |
Definition at line 547 of file TLorentzVector.h.
|
inline |
Definition at line 305 of file TLorentzVector.h.
|
inline |
Definition at line 456 of file TLorentzVector.h.
|
inline |
Definition at line 463 of file TLorentzVector.h.
|
inline |
Definition at line 520 of file TLorentzVector.h.
|
inline |
Definition at line 469 of file TLorentzVector.h.
|
inline |
Definition at line 285 of file TLorentzVector.h.
|
inline |
Definition at line 286 of file TLorentzVector.h.
|
inline |
Definition at line 440 of file TLorentzVector.h.
Definition at line 451 of file TLorentzVector.h.
|
inline |
Definition at line 435 of file TLorentzVector.h.
Definition at line 445 of file TLorentzVector.h.
|
inline |
Definition at line 460 of file TLorentzVector.h.
|
inline |
Definition at line 473 of file TLorentzVector.h.
|
inline |
Definition at line 507 of file TLorentzVector.h.
Definition at line 352 of file TLorentzVector.h.
Definition at line 357 of file TLorentzVector.h.
|
inline |
Definition at line 492 of file TLorentzVector.h.
|
inline |
Definition at line 491 of file TLorentzVector.h.
|
inline |
Definition at line 486 of file TLorentzVector.h.
|
inline |
Definition at line 482 of file TLorentzVector.h.
|
inline |
Definition at line 543 of file TLorentzVector.h.
|
inline |
Definition at line 498 of file TLorentzVector.h.
|
inline |
Definition at line 494 of file TLorentzVector.h.
|
inline |
Definition at line 409 of file TLorentzVector.h.
|
inline |
Definition at line 631 of file TLorentzVector.h.
|
inline |
Definition at line 613 of file TLorentzVector.h.
|
inline |
Definition at line 524 of file TLorentzVector.h.
|
inline |
Definition at line 401 of file TLorentzVector.h.
TLorentzVector & TLorentzVector::operator*= | ( | const TLorentzRotation & | m | ) |
Definition at line 285 of file TLorentzVector.cxx.
|
inline |
Definition at line 579 of file TLorentzVector.h.
|
inline |
Definition at line 395 of file TLorentzVector.h.
|
inline |
Definition at line 371 of file TLorentzVector.h.
|
inline |
Definition at line 375 of file TLorentzVector.h.
|
inline |
Definition at line 391 of file TLorentzVector.h.
|
inline |
Definition at line 381 of file TLorentzVector.h.
|
inline |
Definition at line 385 of file TLorentzVector.h.
|
inline |
Definition at line 365 of file TLorentzVector.h.
|
inline |
Definition at line 405 of file TLorentzVector.h.
|
inline |
Definition at line 362 of file TLorentzVector.h.
|
inline |
Definition at line 363 of file TLorentzVector.h.
|
inline |
Definition at line 284 of file TLorentzVector.h.
|
inline |
Definition at line 415 of file TLorentzVector.h.
Definition at line 427 of file TLorentzVector.h.
|
inline |
Definition at line 413 of file TLorentzVector.h.
Definition at line 423 of file TLorentzVector.h.
|
inline |
Definition at line 297 of file TLorentzVector.h.
|
inline |
Definition at line 539 of file TLorentzVector.h.
Print the TLorentz vector components as (x,y,z,t) and (P,eta,phi,E) representations.
Reimplemented from TObject.
Definition at line 325 of file TLorentzVector.cxx.
|
inline |
Definition at line 555 of file TLorentzVector.h.
|
inline |
Definition at line 417 of file TLorentzVector.h.
Definition at line 431 of file TLorentzVector.h.
|
inline |
Definition at line 281 of file TLorentzVector.h.
|
inline |
Definition at line 282 of file TLorentzVector.h.
|
inline |
Definition at line 283 of file TLorentzVector.h.
Double_t TLorentzVector::Rapidity | ( | ) | const |
Definition at line 279 of file TLorentzVector.cxx.
|
inline |
Definition at line 310 of file TLorentzVector.h.
Definition at line 575 of file TLorentzVector.h.
Definition at line 571 of file TLorentzVector.h.
Definition at line 559 of file TLorentzVector.h.
Definition at line 563 of file TLorentzVector.h.
Definition at line 567 of file TLorentzVector.h.
Definition at line 291 of file TLorentzVector.h.
Definition at line 419 of file TLorentzVector.h.
Definition at line 318 of file TLorentzVector.h.
Definition at line 347 of file TLorentzVector.h.
Definition at line 342 of file TLorentzVector.h.
Definition at line 288 of file TLorentzVector.h.
Definition at line 331 of file TLorentzVector.h.
Definition at line 289 of file TLorentzVector.h.
Definition at line 290 of file TLorentzVector.h.
Definition at line 322 of file TLorentzVector.h.
Definition at line 279 of file TLorentzVector.h.
Definition at line 314 of file TLorentzVector.h.
Definition at line 295 of file TLorentzVector.h.
Definition at line 516 of file TLorentzVector.h.
Definition at line 512 of file TLorentzVector.h.
Definition at line 276 of file TLorentzVector.h.
Definition at line 335 of file TLorentzVector.h.
Definition at line 326 of file TLorentzVector.h.
Definition at line 277 of file TLorentzVector.h.
Definition at line 278 of file TLorentzVector.h.
|
inline |
Definition at line 274 of file TLorentzVector.h.
|
inline |
Definition at line 301 of file TLorentzVector.h.
TLorentzVector & TLorentzVector::Transform | ( | const TLorentzRotation & | m | ) |
Definition at line 291 of file TLorentzVector.cxx.
|
inline |
Definition at line 584 of file TLorentzVector.h.
|
inline |
Definition at line 293 of file TLorentzVector.h.
|
inline |
Definition at line 271 of file TLorentzVector.h.
|
inline |
Definition at line 272 of file TLorentzVector.h.
|
inline |
Definition at line 273 of file TLorentzVector.h.
|
private |
Definition at line 37 of file TLorentzVector.h.
|
private |
Definition at line 36 of file TLorentzVector.h.