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class AliHelix: public TObject

                Implementation of the AliHelix class
        Origin: Marian Ivanov, CERN, marian.ivanov@cern.ch

Function Members (Methods)

public:
AliHelix()
AliHelix(const AliHelix& t)
AliHelix(const AliKalmanTrack& t)
AliHelix(const AliExternalTrackParam& t)
AliHelix(Double_t* x, Double_t* p, Double_t charge = 1, Double_t conversion = 0.)
virtual~AliHelix()
voidTObject::AbstractMethod(const char* method) const
virtual voidTObject::AppendPad(Option_t* option = "")
virtual voidTObject::Browse(TBrowser* b)
static TClass*Class()
virtual const char*TObject::ClassName() const
virtual voidTObject::Clear(Option_t* = "")
virtual TObject*TObject::Clone(const char* newname = "") const
virtual Int_tTObject::Compare(const TObject* obj) const
virtual voidTObject::Copy(TObject& object) const
virtual voidTObject::Delete(Option_t* option = "")MENU
virtual Int_tTObject::DistancetoPrimitive(Int_t px, Int_t py)
virtual voidTObject::Draw(Option_t* option = "")
virtual voidTObject::DrawClass() constMENU
virtual TObject*TObject::DrawClone(Option_t* option = "") constMENU
virtual voidTObject::Dump() constMENU
virtual voidTObject::Error(const char* method, const char* msgfmt) const
voidEvaluate(Double_t t, Double_t* r)
voidEvaluate(Double_t t, Double_t* r, Double_t* g, Double_t* gg)
virtual voidTObject::Execute(const char* method, const char* params, Int_t* error = 0)
virtual voidTObject::Execute(TMethod* method, TObjArray* params, Int_t* error = 0)
virtual voidTObject::ExecuteEvent(Int_t event, Int_t px, Int_t py)
virtual voidTObject::Fatal(const char* method, const char* msgfmt) const
virtual TObject*TObject::FindObject(const char* name) const
virtual TObject*TObject::FindObject(const TObject* obj) const
voidGetAngle(Double_t t1, AliHelix& h, Double_t t2, Double_t* angle)
Int_tGetClosestPhases(AliHelix& h, Double_t** phase)
virtual Option_t*TObject::GetDrawOption() const
static Long_tTObject::GetDtorOnly()
Double_tGetHelix(Int_t i) const
Double_tGetHelixR(Double_t phase = 0)
Double_tGetHelixZ(Double_t phase = 0)
virtual const char*TObject::GetIconName() const
voidGetMomentum(Double_t phase, Double_t* p, Double_t conversion = 0., Double_t* xr = 0)
virtual const char*TObject::GetName() const
virtual char*TObject::GetObjectInfo(Int_t px, Int_t py) const
static Bool_tTObject::GetObjectStat()
virtual Option_t*TObject::GetOption() const
Double_tGetPhase(Double_t x0, Double_t y0)
Int_tGetPhase(Double_t r0, Double_t* t)
Double_tGetPhaseZ(Double_t z0)
Double_tGetPointAngle(AliHelix& h, Double_t* phase, const Float_t* vertex)
Int_tGetRPHIintersections(AliHelix& h, Double_t** phase, Double_t* ri, Double_t cut = 3.)
virtual const char*TObject::GetTitle() const
virtual UInt_tTObject::GetUniqueID() const
virtual Bool_tTObject::HandleTimer(TTimer* timer)
virtual ULong_tTObject::Hash() const
virtual voidTObject::Info(const char* method, const char* msgfmt) const
virtual Bool_tTObject::InheritsFrom(const char* classname) const
virtual Bool_tTObject::InheritsFrom(const TClass* cl) const
virtual voidTObject::Inspect() constMENU
voidTObject::InvertBit(UInt_t f)
virtual TClass*IsA() const
virtual Bool_tTObject::IsEqual(const TObject* obj) const
virtual Bool_tTObject::IsFolder() const
Bool_tTObject::IsOnHeap() const
virtual Bool_tTObject::IsSortable() const
Bool_tTObject::IsZombie() const
Int_tLinearDCA(AliHelix& h, Double_t& t1, Double_t& t2, Double_t& R, Double_t& dist)
virtual voidTObject::ls(Option_t* option = "") const
voidTObject::MayNotUse(const char* method) const
virtual Bool_tTObject::Notify()
voidTObject::Obsolete(const char* method, const char* asOfVers, const char* removedFromVers) const
static voidTObject::operator delete(void* ptr)
static voidTObject::operator delete(void* ptr, void* vp)
static voidTObject::operator delete[](void* ptr)
static voidTObject::operator delete[](void* ptr, void* vp)
void*TObject::operator new(size_t sz)
void*TObject::operator new(size_t sz, void* vp)
void*TObject::operator new[](size_t sz)
void*TObject::operator new[](size_t sz, void* vp)
virtual voidTObject::Paint(Option_t* option = "")
Int_tParabolicDCA(AliHelix& h, Double_t& t1, Double_t& t2, Double_t& R, Double_t& dist, Int_t iter = 1)
Int_tParabolicDCA2(AliHelix& h, Double_t& t1, Double_t& t2, Double_t& R, Double_t& dist, Double_t* err, Int_t iter = 1)
virtual voidTObject::Pop()
virtual voidTObject::Print(Option_t* option = "") const
virtual Int_tTObject::Read(const char* name)
virtual voidTObject::RecursiveRemove(TObject* obj)
voidTObject::ResetBit(UInt_t f)
virtual voidTObject::SaveAs(const char* filename = "", Option_t* option = "") constMENU
virtual voidTObject::SavePrimitive(basic_ostream<char,char_traits<char> >& out, Option_t* option = "")
voidTObject::SetBit(UInt_t f)
voidTObject::SetBit(UInt_t f, Bool_t set)
virtual voidTObject::SetDrawOption(Option_t* option = "")MENU
static voidTObject::SetDtorOnly(void* obj)
static voidTObject::SetObjectStat(Bool_t stat)
virtual voidTObject::SetUniqueID(UInt_t uid)
virtual voidShowMembers(TMemberInspector&)
virtual voidStreamer(TBuffer&)
voidStreamerNVirtual(TBuffer& ClassDef_StreamerNVirtual_b)
virtual voidTObject::SysError(const char* method, const char* msgfmt) const
Bool_tTObject::TestBit(UInt_t f) const
Int_tTObject::TestBits(UInt_t f) const
virtual voidTObject::UseCurrentStyle()
virtual voidTObject::Warning(const char* method, const char* msgfmt) const
virtual Int_tTObject::Write(const char* name = 0, Int_t option = 0, Int_t bufsize = 0)
virtual Int_tTObject::Write(const char* name = 0, Int_t option = 0, Int_t bufsize = 0) const
protected:
virtual voidTObject::DoError(int level, const char* location, const char* fmt, va_list va) const
voidTObject::MakeZombie()
private:
AliHelix&operator=(const AliHelix& helix)

Data Members

public:
Double_tfHelix[9]helix parameters

Class Charts

Inheritance Chart:
TObject
←
AliHelix

Function documentation

AliHelix()
 Default constructor
AliHelix(const AliHelix& t)
AliHelix(const AliKalmanTrack& t)
AliHelix(const AliExternalTrackParam& t)
AliHelix(Double_t* x, Double_t* p, Double_t charge = 1, Double_t conversion = 0.)
void GetMomentum(Double_t phase, Double_t* p, Double_t conversion = 0., Double_t* xr = 0)
 return  momentum at given phase
void GetAngle(Double_t t1, AliHelix& h, Double_t t2, Double_t* angle)
void Evaluate(Double_t t, Double_t* r, Double_t* g, Double_t* gg)
 Calculate position of a point on a track and some derivatives at given phase
Int_t GetClosestPhases(AliHelix& h, Double_t** phase)
 get phases to minimize distances
Double_t GetPointAngle(AliHelix& h, Double_t* phase, const Float_t* vertex)
 get point angle bettwen two helixes
Double_t GetPhase(Double_t x0, Double_t y0)
calculate helix param at given x,y  point

Double_t phase2 = TMath::ATan2((y-fHelix[0]), (x-fHelix[5]))- TMath::Pi()/2.;
Int_t GetPhase(Double_t r0, Double_t* t)
calculate helix param at given r  point - return nearest point ()

 not implemented yet
Double_t GetPhaseZ(Double_t z0)
Int_t GetRPHIintersections(AliHelix& h, Double_t** phase, Double_t* ri, Double_t cut = 3.)
 This function returns  phase vectors with intesection between helix (0, 1 or 2)
 in x-y plane projection


  Double_t * c1 = &fHelix[6];
Double_t * c2 = &(h.fHelix[6]);
  Double_t  c1[3] = {fHelix[5],fHelix[0],fHelix[8]};
Int_t LinearDCA(AliHelix& h, Double_t& t1, Double_t& t2, Double_t& R, Double_t& dist)

 find intersection using linear approximation
Int_t ParabolicDCA(AliHelix& h, Double_t& t1, Double_t& t2, Double_t& R, Double_t& dist, Int_t iter = 1)

 find intersection using linear fit
Int_t ParabolicDCA2(AliHelix& h, Double_t& t1, Double_t& t2, Double_t& R, Double_t& dist, Double_t* err, Int_t iter = 1)

 find intersection using linear fit
void Evaluate(Double_t t, Double_t* r)
 calculate poitition at given phase t
Double_t GetHelixR(Double_t phase = 0)
Double_t GetHelixZ(Double_t phase = 0)
virtual ~AliHelix()
{}
Double_t GetHelix(Int_t i) const
{return fHelix[i];}
AliHelix & operator=(const AliHelix& helix)