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TBtree Class Reference

B-tree class.

TBtree inherits from the TSeqCollection ABC.

B-tree Implementation notes

This implements B-trees with several refinements. Most of them can be found in Knuth Vol 3, but some were developed to adapt to restrictions imposed by C++. First, a restatement of Knuth's properties that a B-tree must satisfy, assuming we make the enhancement he suggests in the paragraph at the bottom of page 476. Instead of storing null pointers to non-existent nodes (which Knuth calls the leaves) we utilize the space to store keys. Therefore, what Knuth calls level (l-1) is the bottom of our tree, and we call the nodes at this level LeafNodes. Other nodes are called InnerNodes. The other enhancement we have adopted is in the paragraph at the bottom of page 477: overflow control.

The following are modifications of Knuth's properties on page 478:

  1. Every InnerNode has at most Order keys, and at most Order+1 sub-trees.
  2. Every LeafNode has at most 2*(Order+1) keys.
  3. An InnerNode with k keys has k+1 sub-trees.
  4. Every InnerNode that is not the root has at least InnerLowWaterMark keys.
  5. Every LeafNode that is not the root has at least LeafLowWaterMark keys.
  6. If the root is a LeafNode, it has at least one key.
  7. If the root is an InnerNode, it has at least one key and two sub-trees.
  8. All LeafNodes are the same distance from the root as all the other LeafNodes.
  9. For InnerNode n with key n[i].key, then sub-tree n[i-1].tree contains all keys < n[i].key, and sub-tree n[i].tree contains all keys >= n[i].key.

Order is at least 3.

The values of InnerLowWaterMark and LeafLowWaterMark may actually be set by the user when the tree is initialized, but currently they are set automatically to:

InnerLowWaterMark = ceiling(Order/2)
LeafLowWaterMark = Order - 1

If the tree is only filled, then all the nodes will be at least 2/3 full. They will almost all be exactly 2/3 full if the elements are added to the tree in order (either increasing or decreasing). [Knuth says McCreight's experiments showed almost 100% memory utilization. I don't see how that can be given the algorithms that Knuth gives. McCreight must have used a different scheme for balancing. [No, he used a different scheme for splitting: he did a two-way split instead of the three way split as we do here. Which means that McCreight does better on insertion of ordered data, but we should do better on insertion of random data.]]

It must also be noted that B-trees were designed for DISK access algorithms, not necessarily in-memory sorting, as we intend it to be used here. However, if the order is kept small (< 6?) any inefficiency is negligible for in-memory sorting. Knuth points out that balanced trees are actually preferable for memory sorting. I'm not sure that I believe this, but it's interesting. Also, deleting elements from balanced binary trees, being beyond the scope of Knuth's book (p. 465), is beyond my scope. B-trees are good enough.

A B-tree is declared to be of a certain ORDER (3 by default). This number determines the number of keys contained in any interior node of the tree. Each interior node will contain ORDER keys, and therefore ORDER+1 pointers to sub-trees. The keys are numbered and indexed 1 to ORDER while the pointers are numbered and indexed 0 to ORDER. The 0th ptr points to the sub-tree of all elements that are less than key[1]. Ptr[1] points to the sub-tree that contains all the elements greater than key[1] and less than key[2]. etc. The array of pointers and keys is allocated as ORDER+1 pairs of keys and nodes, meaning that one key field (key[0]) is not used and therefore wasted. Given that the number of interior nodes is small, that this waste allows fewer cases of special code, and that it is useful in certain of the methods, it was felt to be a worthwhile waste.

The size of the exterior nodes (leaf nodes) does not need to be related to the size of the interior nodes at all. Since leaf nodes contain only keys, they may be as large or small as we like independent of the size of the interior nodes. For no particular reason other than it seems like a good idea, we will allocate 2*(ORDER+1) keys in each leaf node, and they will be numbered and indexed from 0 to 2*ORDER+1. It does have the advantage of keeping the size of the leaf and interior arrays the same, so that if we find allocation and de-allocation of these arrays expensive, we can modify their allocation to use a garbage ring, or something.

Both of these numbers will be run-time constants associated with each tree (each tree at run-time can be of a different order). The variable "order" is the order of the tree, and the inclusive upper limit on the indices of the keys in the interior nodes. The variable "order2" is the inclusive upper limit on the indices of the leaf nodes, and is designed

(1) to keep the sizes of the two kinds of nodes the same;
(2) to keep the expressions involving the arrays of keys looking
somewhat the same: lower limit upper limit
for inner nodes: 1 order
for leaf nodes: 0 order2
Remember that index 0 of the inner nodes is special.

Currently, order2 = 2*(order+1).

Picture: (also see Knuth Vol 3 pg 478)
+--+--+--+--+--+--...
| | | | | |
parent--->| | | |
| | | |
+*-+*-+*-+--+--+--...
| | |
+----+ | +-----+
| +-----+ |
V | V
+----------+ | +----------+
| | | | |
this->| | | | |<--sib
+----------+ | +----------+
V

It is conceptually VERY convenient to think of the data as being the very first element of the sib node. Any primitive that tells sib to perform some action on n nodes should include this 'hidden' element. For InnerNodes, the hidden element has (physical) index 0 in the array, and in LeafNodes, the hidden element has (virtual) index -1 in the array. Therefore, there are two 'size' primitives for nodes:

Psize - the physical size: how many elements are contained in the
array in the node.
Vsize - the 'virtual' size; if the node is pointed to by
element 0 of the parent node, then Vsize == Psize;
otherwise the element in the parent item that points to this
node 'belongs' to this node, and Vsize == Psize+1;

Parent nodes are always InnerNodes.

These are the primitive operations on Nodes:

Append(elt) - adds an element to the end of the array of elements in a
node. It must never be called where appending the element
would fill the node.
Split() - divide a node in two, and create two new nodes.
SplitWith(sib) - create a third node between this node and the sib node,
divvying up the elements of their arrays.
PushLeft(n) - move n elements into the left sibling
PushRight(n) - move n elements into the right sibling
BalanceWithRight() - even up the number of elements in the two nodes.
BalanceWithLeft() - ditto

To allow this implementation of btrees to also be an implementation of sorted arrays/lists, the overhead is included to allow O(log n) access of elements by their rank (`give me the 5th largest element'). Therefore, each Item keeps track of the number of keys in and below it in the tree (remember, each item's tree is all keys to the RIGHT of the item's own key).

[ [ < 0 1 2 3 > 4 < 5 6 7 > 8 < 9 10 11 12 > ] 13 [ < 14 15 16 > 17 < 18 19 20 > ] ]
4 1 1 1 1 4 1 1 1 5 1 1 1 1 7 3 1 1 1 4 1 1 1

Definition at line 42 of file TBtree.h.

Public Types

typedef TBtreeIter Iterator_t
 
- Public Types inherited from TCollection
enum  { kInitCapacity = 16, kInitHashTableCapacity = 17 }
 
- Public Types inherited from TObject
enum  { kIsOnHeap = 0x01000000, kNotDeleted = 0x02000000, kZombie = 0x04000000, kBitMask = 0x00ffffff }
 
enum  { kSingleKey = BIT(0), kOverwrite = BIT(1), kWriteDelete = BIT(2) }
 
enum  EStatusBits {
  kCanDelete = BIT(0), kMustCleanup = BIT(3), kObjInCanvas = BIT(3), kIsReferenced = BIT(4),
  kHasUUID = BIT(5), kCannotPick = BIT(6), kNoContextMenu = BIT(8), kInvalidObject = BIT(13)
}
 

Public Member Functions

 TBtree (Int_t ordern=3)
 Create a B-tree of certain order (by default 3). More...
 
virtual ~TBtree ()
 Delete B-tree. More...
 
void Add (TObject *obj)
 Add object to B-tree. More...
 
void AddAfter (const TObject *, TObject *obj)
 
void AddAt (TObject *obj, Int_t)
 
void AddBefore (const TObject *, TObject *obj)
 
void AddFirst (TObject *obj)
 
void AddLast (TObject *obj)
 
TObjectAfter (const TObject *obj) const
 Cannot use this method since B-tree decides order. More...
 
TObjectAt (Int_t idx) const
 
TObjectBefore (const TObject *obj) const
 May not use this method since B-tree decides order. More...
 
void Clear (Option_t *option="")
 Remove all objects from B-tree. More...
 
void Delete (Option_t *option="")
 Remove all objects from B-tree AND delete all heap based objects. More...
 
TObjectFindObject (const char *name) const
 Find object using its name (see object's GetName()). More...
 
TObjectFindObject (const TObject *obj) const
 Find object using the objects Compare() member function. More...
 
TObjectFirst () const
 
TObject ** GetObjectRef (const TObject *) const
 
TObjectLast () const
 
TIteratorMakeIterator (Bool_t dir=kIterForward) const
 Returns a B-tree iterator. More...
 
TObjectoperator[] (Int_t i) const
 
Int_t Order ()
 
Int_t Rank (const TObject *obj) const
 Returns the rank of the object in the tree. More...
 
TObjectRemove (TObject *obj)
 Remove an object from the tree. More...
 
- Public Member Functions inherited from TSeqCollection
virtual ~TSeqCollection ()
 
virtual Int_t GetLast () const
 Returns index of last object in collection. More...
 
virtual Int_t IndexOf (const TObject *obj) const
 Return index of object in collection. More...
 
virtual Bool_t IsSorted () const
 
Int_t LastIndex () const
 
Long64_t Merge (TCollection *list)
 Merge this collection with all collections coming in the input list. More...
 
virtual void RemoveAfter (TObject *after)
 
virtual TObjectRemoveAt (Int_t idx)
 
virtual void RemoveBefore (TObject *before)
 
virtual void RemoveFirst ()
 
virtual void RemoveLast ()
 
void UnSort ()
 
- Public Member Functions inherited from TCollection
virtual ~TCollection ()
 
virtual void AddAll (const TCollection *col)
 Add all objects from collection col to this collection. More...
 
void AddVector (TObject *obj1,...)
 Add all arguments to the collection. More...
 
Bool_t AssertClass (TClass *cl) const
 Make sure all objects in this collection inherit from class cl. More...
 
TIter begin () const
 
void Browse (TBrowser *b)
 Browse this collection (called by TBrowser). More...
 
Int_t Capacity () const
 
virtual TObjectClone (const char *newname="") const
 Make a clone of an collection using the Streamer facility. More...
 
Int_t Compare (const TObject *obj) const
 Compare two TCollection objects. More...
 
Bool_t Contains (const char *name) const
 
Bool_t Contains (const TObject *obj) const
 
virtual void Draw (Option_t *option="")
 Draw all objects in this collection. More...
 
virtual void Dump () const
 Dump all objects in this collection. More...
 
TIter end () const
 
virtual Int_t GetEntries () const
 
virtual const char * GetName () const
 Return name of this collection. More...
 
virtual Int_t GetSize () const
 
virtual Int_t GrowBy (Int_t delta) const
 Increase the collection's capacity by delta slots. More...
 
ULong_t Hash () const
 Return hash value for this object. More...
 
Bool_t IsArgNull (const char *where, const TObject *obj) const
 Returns true if object is a null pointer. More...
 
virtual Bool_t IsEmpty () const
 
virtual Bool_t IsFolder () const
 Returns kTRUE in case object contains browsable objects (like containers or lists of other objects). More...
 
Bool_t IsOwner () const
 
Bool_t IsSortable () const
 
virtual void ls (Option_t *option="") const
 List (ls) all objects in this collection. More...
 
virtual TIteratorMakeReverseIterator () const
 
TObjectoperator() (const char *name) const
 Find an object in this collection by name. More...
 
virtual void Paint (Option_t *option="")
 Paint all objects in this collection. More...
 
virtual void Print (Option_t *option="") const
 Default print for collections, calls Print(option, 1). More...
 
virtual void Print (Option_t *option, Int_t recurse) const
 Print the collection header and its elements. More...
 
virtual void Print (Option_t *option, const char *wildcard, Int_t recurse=1) const
 Print the collection header and its elements that match the wildcard. More...
 
virtual void Print (Option_t *option, TPRegexp &regexp, Int_t recurse=1) const
 Print the collection header and its elements that match the regexp. More...
 
virtual void RecursiveRemove (TObject *obj)
 Remove object from this collection and recursively remove the object from all other objects (and collections). More...
 
virtual void RemoveAll (TCollection *col)
 Remove all objects in collection col from this collection. More...
 
void RemoveAll ()
 
void SetCurrentCollection ()
 Set this collection to be the globally accesible collection. More...
 
void SetName (const char *name)
 
virtual void SetOwner (Bool_t enable=kTRUE)
 Set whether this collection is the owner (enable==true) of its content. More...
 
virtual Int_t Write (const char *name=0, Int_t option=0, Int_t bufsize=0)
 Write all objects in this collection. More...
 
virtual Int_t Write (const char *name=0, Int_t option=0, Int_t bufsize=0) const
 Write all objects in this collection. 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 const char * ClassName () const
 Returns name of class to which the object belongs. More...
 
virtual void Copy (TObject &object) const
 Copy this to obj. More...
 
virtual Int_t DistancetoPrimitive (Int_t px, Int_t py)
 Computes distance from point (px,py) to the object. More...
 
virtual void DrawClass () const
 Draw class inheritance tree of the class to which this object belongs. More...
 
virtual TObjectDrawClone (Option_t *option="") const
 Draw a clone of this object in the current pad. 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 Option_tGetDrawOption () 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 char * GetObjectInfo (Int_t px, Int_t py) const
 Returns string containing info about the object at position (px,py). More...
 
virtual Option_tGetOption () 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 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...
 
Bool_t IsOnHeap () const
 
Bool_t IsZombie () const
 
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...
 
voidoperator new (size_t sz)
 
voidoperator new (size_t sz, void *vp)
 
voidoperator new[] (size_t sz)
 
voidoperator new[] (size_t sz, void *vp)
 
TObjectoperator= (const TObject &rhs)
 TObject assignment operator. More...
 
virtual void Pop ()
 Pop on object drawn in a pad to the top of the display list. More...
 
virtual Int_t Read (const char *name)
 Read contents of object with specified name from the current directory. 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, Bool_t set)
 Set or unset the user status bits as specified in f. More...
 
void SetBit (UInt_t f)
 
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...
 
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...
 

Protected Member Functions

void DecrNofKeys ()
 
Int_t IdxAdd (const TObject &obj)
 Add object and return its index in the tree. More...
 
void IncrNofKeys ()
 
- Protected Member Functions inherited from TSeqCollection
 TSeqCollection ()
 
virtual void Changed ()
 
- Protected Member Functions inherited from TCollection
 TCollection ()
 
virtual const char * GetCollectionEntryName (TObject *entry) const
 For given collection entry return the string that is used to identify the object and, potentially, perform wildcard/regexp filtering on. More...
 
virtual void PrintCollectionEntry (TObject *entry, Option_t *option, Int_t recurse) const
 Print the collection entry. More...
 
virtual void PrintCollectionHeader (Option_t *option) const
 Print the collection header. 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 ()
 

Private Member Functions

void Init (Int_t i)
 Initialize a B-tree. More...
 
void RootIsEmpty ()
 If root is empty clean up its space. More...
 
void RootIsFull ()
 The root of the tree is full. More...
 

Private Attributes

Int_t fInnerLowWaterMark
 
Int_t fInnerMaxIndex
 
Int_t fLeafLowWaterMark
 
Int_t fLeafMaxIndex
 
Int_t fOrder
 
Int_t fOrder2
 
TBtNodefRoot
 

Friends

class TBtInnerNode
 
class TBtLeafNode
 
class TBtNode
 

Additional Inherited Members

- Static Public Member Functions inherited from TSeqCollection
static Int_t ObjCompare (TObject *a, TObject *b)
 Compare to objects in the collection. Use member Compare() of object a. More...
 
static void QSort (TObject **a, Int_t first, Int_t last)
 Sort array of TObject pointers using a quicksort algorithm. More...
 
static void QSort (TObject **a, TObject **b, Int_t first, Int_t last)
 
static void QSort (TObject **a, Int_t nBs, TObject ***b, Int_t first, Int_t last)
 Sort array a of TObject pointers using a quicksort algorithm. More...
 
- Static Public Member Functions inherited from TCollection
static void EmptyGarbageCollection ()
 Do the garbage collection. More...
 
static void GarbageCollect (TObject *obj)
 Add to the list of things to be cleaned up. More...
 
static TCollectionGetCurrentCollection ()
 Return the globally accessible collection. More...
 
static void StartGarbageCollection ()
 Set up for garbage collection. More...
 
- 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 Types inherited from TCollection
enum  { kIsOwner = BIT(14) }
 
- Protected Attributes inherited from TSeqCollection
Bool_t fSorted
 
- Protected Attributes inherited from TCollection
TString fName
 
Int_t fSize
 

#include <TBtree.h>

Inheritance diagram for TBtree:
[legend]

Member Typedef Documentation

◆ Iterator_t

Definition at line 73 of file TBtree.h.

Constructor & Destructor Documentation

◆ TBtree()

TBtree::TBtree ( Int_t  ordern = 3)

Create a B-tree of certain order (by default 3).

Definition at line 179 of file TBtree.cxx.

◆ ~TBtree()

TBtree::~TBtree ( )
virtual

Delete B-tree.

Objects are not deleted unless the TBtree is the owner (set via SetOwner()).

Definition at line 188 of file TBtree.cxx.

Member Function Documentation

◆ Add()

void TBtree::Add ( TObject obj)
virtual

Add object to B-tree.

Reimplemented from TSeqCollection.

Definition at line 199 of file TBtree.cxx.

◆ AddAfter()

void TBtree::AddAfter ( const TObject ,
TObject obj 
)
inlinevirtual

Implements TSeqCollection.

Definition at line 88 of file TBtree.h.

◆ AddAt()

void TBtree::AddAt ( TObject obj,
Int_t   
)
inlinevirtual

Implements TSeqCollection.

Definition at line 87 of file TBtree.h.

◆ AddBefore()

void TBtree::AddBefore ( const TObject ,
TObject obj 
)
inlinevirtual

Implements TSeqCollection.

Definition at line 89 of file TBtree.h.

◆ AddFirst()

void TBtree::AddFirst ( TObject obj)
inlinevirtual

Implements TSeqCollection.

Definition at line 85 of file TBtree.h.

◆ AddLast()

void TBtree::AddLast ( TObject obj)
inlinevirtual

Implements TSeqCollection.

Definition at line 86 of file TBtree.h.

◆ After()

TObject * TBtree::After ( const TObject obj) const
virtual

Cannot use this method since B-tree decides order.

Implements TSeqCollection.

Definition at line 227 of file TBtree.cxx.

◆ At()

TObject * TBtree::At ( Int_t  idx) const
inlinevirtual

Implements TSeqCollection.

Definition at line 376 of file TBtree.h.

◆ Before()

TObject * TBtree::Before ( const TObject obj) const
virtual

May not use this method since B-tree decides order.

Implements TSeqCollection.

Definition at line 236 of file TBtree.cxx.

◆ Clear()

void TBtree::Clear ( Option_t option = "")
virtual

Remove all objects from B-tree.

Does NOT delete objects unless the TBtree is the owner (set via SetOwner()).

Implements TCollection.

Definition at line 246 of file TBtree.cxx.

◆ DecrNofKeys()

void TBtree::DecrNofKeys ( )
inlineprotected

Definition at line 65 of file TBtree.h.

◆ Delete()

void TBtree::Delete ( Option_t option = "")
virtual

Remove all objects from B-tree AND delete all heap based objects.

Implements TCollection.

Definition at line 259 of file TBtree.cxx.

◆ FindObject() [1/2]

TObject * TBtree::FindObject ( const char *  name) const
virtual

Find object using its name (see object's GetName()).

Requires sequential search of complete tree till object is found.

Reimplemented from TCollection.

Definition at line 274 of file TBtree.cxx.

◆ FindObject() [2/2]

TObject * TBtree::FindObject ( const TObject obj) const
virtual

Find object using the objects Compare() member function.

Reimplemented from TCollection.

Definition at line 282 of file TBtree.cxx.

◆ First()

TObject * TBtree::First ( ) const
inlinevirtual

Implements TSeqCollection.

Definition at line 381 of file TBtree.h.

◆ GetObjectRef()

TObject** TBtree::GetObjectRef ( const TObject ) const
inlinevirtual

Implements TCollection.

Definition at line 81 of file TBtree.h.

◆ IdxAdd()

Int_t TBtree::IdxAdd ( const TObject obj)
protected

Add object and return its index in the tree.

Definition at line 300 of file TBtree.cxx.

◆ IncrNofKeys()

void TBtree::IncrNofKeys ( )
inlineprotected

Definition at line 64 of file TBtree.h.

◆ Init()

void TBtree::Init ( Int_t  i)
private

Initialize a B-tree.

Definition at line 343 of file TBtree.cxx.

◆ Last()

TObject * TBtree::Last ( ) const
inlinevirtual

Implements TSeqCollection.

Definition at line 386 of file TBtree.h.

◆ MakeIterator()

TIterator * TBtree::MakeIterator ( Bool_t  dir = kIterForward) const
virtual

Returns a B-tree iterator.

Implements TCollection.

Definition at line 384 of file TBtree.cxx.

◆ operator[]()

TObject * TBtree::operator[] ( Int_t  i) const
inline

Definition at line 371 of file TBtree.h.

◆ Order()

Int_t TBtree::Order ( )
inline

Definition at line 100 of file TBtree.h.

◆ Rank()

Int_t TBtree::Rank ( const TObject obj) const

Returns the rank of the object in the tree.

Definition at line 392 of file TBtree.cxx.

◆ Remove()

TObject * TBtree::Remove ( TObject obj)
virtual

Remove an object from the tree.

Implements TCollection.

Definition at line 407 of file TBtree.cxx.

◆ RootIsEmpty()

void TBtree::RootIsEmpty ( )
private

If root is empty clean up its space.

Definition at line 440 of file TBtree.cxx.

◆ RootIsFull()

void TBtree::RootIsFull ( )
private

The root of the tree is full.

Create an InnerNode that points to it, and then inform the InnerNode that it is full.

Definition at line 429 of file TBtree.cxx.

Friends And Related Function Documentation

◆ TBtInnerNode

friend class TBtInnerNode
friend

Definition at line 45 of file TBtree.h.

◆ TBtLeafNode

friend class TBtLeafNode
friend

Definition at line 46 of file TBtree.h.

◆ TBtNode

friend class TBtNode
friend

Definition at line 44 of file TBtree.h.

Member Data Documentation

◆ fInnerLowWaterMark

Int_t TBtree::fInnerLowWaterMark
private

Definition at line 54 of file TBtree.h.

◆ fInnerMaxIndex

Int_t TBtree::fInnerMaxIndex
private

Definition at line 56 of file TBtree.h.

◆ fLeafLowWaterMark

Int_t TBtree::fLeafLowWaterMark
private

Definition at line 55 of file TBtree.h.

◆ fLeafMaxIndex

Int_t TBtree::fLeafMaxIndex
private

Definition at line 57 of file TBtree.h.

◆ fOrder

Int_t TBtree::fOrder
private

Definition at line 51 of file TBtree.h.

◆ fOrder2

Int_t TBtree::fOrder2
private

Definition at line 52 of file TBtree.h.

◆ fRoot

TBtNode* TBtree::fRoot
private

Definition at line 49 of file TBtree.h.


The documentation for this class was generated from the following files: