ROOT 6.18/05 Reference Guide |
Class representing a helix curve.
A helix is a curve defined by the following equations:
where:
In particular, a helix describes the trajectory of a charged particle in magnetic field. In such case, the helix is right-handed for negative particle charge. To define a helix, one must define:
A helix provides:
Definition at line 20 of file TGeoHelix.h.
Public Types | |
enum | EGeoHelixTypes { kHelixNeedUpdate = BIT(16) , kHelixStraight = BIT(17) , kHelixCircle = BIT(18) } |
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 | |
TGeoHelix () | |
Dummy constructor. More... | |
TGeoHelix (Double_t curvature, Double_t step, Int_t charge=1) | |
Normal constructor. More... | |
virtual | ~TGeoHelix () |
Destructor. More... | |
Double_t | ComputeSafeStep (Double_t epsil=1E-6) const |
Compute safe linear step that can be made such that the error between linear-helix extrapolation is less than EPSIL. More... | |
const Double_t * | GetCurrentDirection () const |
const Double_t * | GetCurrentPoint () const |
Double_t | GetStep () const |
Double_t | GetTotalCurvature () const |
Compute helix total curvature. More... | |
Double_t | GetXYcurvature () const |
void | InitDirection (Double_t *dir, Bool_t is_normalized=kTRUE) |
Initialize particle direction (tangent on the helix in initial point) More... | |
void | InitDirection (Double_t dirx, Double_t diry, Double_t dirz, Bool_t is_normalized=kTRUE) |
Initialize particle direction (tangent on the helix in initial point) More... | |
void | InitPoint (Double_t *point) |
Set initial point on the helix. More... | |
void | InitPoint (Double_t x0, Double_t y0, Double_t z0) |
Initialize coordinates of a point on the helix. More... | |
Bool_t | IsRightHanded () const |
void | ResetStep () |
Reset current point/direction to initial values. More... | |
void | SetCharge (Int_t charge) |
Positive charge means left-handed helix. More... | |
void | SetField (Double_t bx, Double_t by, Double_t bz, Bool_t is_normalized=kTRUE) |
Initialize particle direction (tangent on the helix in initial point) More... | |
void | SetHelixStep (Double_t hstep) |
Set Z step of the helix on a complete turn. Positive or null. More... | |
void | SetXYcurvature (Double_t curvature) |
Set XY curvature: c = 1/Rxy. More... | |
void | Step (Double_t step) |
Make a step from current point along the helix and compute new point, direction and angle To reach a plane/ shape boundary, one has to: More... | |
Double_t | StepToPlane (Double_t *point, Double_t *norm) |
Propagate initial point up to a given Z position in MARS. More... | |
void | UpdateHelix () |
Update the local helix matrix. More... | |
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 Member Functions | |
TGeoHelix (const TGeoHelix &) | |
TGeoHelix & | operator= (const TGeoHelix &) |
Private Attributes | |
Double_t | fB [3] |
Double_t | fC |
Double_t | fDir [3] |
Double_t | fDirInit [3] |
TGeoHMatrix * | fMatrix |
Double_t | fPhi |
Double_t | fPoint [3] |
Double_t | fPointInit [3] |
Int_t | fQ |
Double_t | fS |
Double_t | fStep |
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 <TGeoHelix.h>
Enumerator | |
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kHelixNeedUpdate | |
kHelixStraight | |
kHelixCircle |
Definition at line 38 of file TGeoHelix.h.
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private |
TGeoHelix::TGeoHelix | ( | ) |
Dummy constructor.
Definition at line 62 of file TGeoHelix.cxx.
Normal constructor.
Definition at line 83 of file TGeoHelix.cxx.
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virtual |
Destructor.
Definition at line 105 of file TGeoHelix.cxx.
Compute safe linear step that can be made such that the error between linear-helix extrapolation is less than EPSIL.
Definition at line 114 of file TGeoHelix.cxx.
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inline |
Definition at line 56 of file TGeoHelix.h.
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inline |
Definition at line 55 of file TGeoHelix.h.
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inline |
Definition at line 58 of file TGeoHelix.h.
Double_t TGeoHelix::GetTotalCurvature | ( | ) | const |
Compute helix total curvature.
Definition at line 166 of file TGeoHelix.cxx.
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inline |
Definition at line 57 of file TGeoHelix.h.
Initialize particle direction (tangent on the helix in initial point)
Definition at line 158 of file TGeoHelix.cxx.
void TGeoHelix::InitDirection | ( | Double_t | dirx, |
Double_t | diry, | ||
Double_t | dirz, | ||
Bool_t | is_normalized = kTRUE |
||
) |
Initialize particle direction (tangent on the helix in initial point)
Definition at line 144 of file TGeoHelix.cxx.
Set initial point on the helix.
Definition at line 136 of file TGeoHelix.cxx.
Initialize coordinates of a point on the helix.
Definition at line 125 of file TGeoHelix.cxx.
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inline |
Definition at line 60 of file TGeoHelix.h.
void TGeoHelix::ResetStep | ( | ) |
Reset current point/direction to initial values.
Definition at line 235 of file TGeoHelix.cxx.
Positive charge means left-handed helix.
Definition at line 192 of file TGeoHelix.cxx.
Initialize particle direction (tangent on the helix in initial point)
Definition at line 207 of file TGeoHelix.cxx.
Set Z step of the helix on a complete turn. Positive or null.
Definition at line 221 of file TGeoHelix.cxx.
Set XY curvature: c = 1/Rxy.
Definition at line 175 of file TGeoHelix.cxx.
Make a step from current point along the helix and compute new point, direction and angle To reach a plane/ shape boundary, one has to:
Definition at line 253 of file TGeoHelix.cxx.
Propagate initial point up to a given Z position in MARS.
Definition at line 285 of file TGeoHelix.cxx.
void TGeoHelix::UpdateHelix | ( | ) |
Update the local helix matrix.
Definition at line 339 of file TGeoHelix.cxx.
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private |
Definition at line 31 of file TGeoHelix.h.
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private |
Definition at line 23 of file TGeoHelix.h.
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private |
Definition at line 30 of file TGeoHelix.h.
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private |
Definition at line 28 of file TGeoHelix.h.
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private |
Definition at line 33 of file TGeoHelix.h.
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private |
Definition at line 26 of file TGeoHelix.h.
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private |
Definition at line 29 of file TGeoHelix.h.
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private |
Definition at line 27 of file TGeoHelix.h.
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private |
Definition at line 32 of file TGeoHelix.h.
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private |
Definition at line 24 of file TGeoHelix.h.
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private |
Definition at line 25 of file TGeoHelix.h.