TClonesArray

class TClonesArray : public TObjArray

    public:

           TClonesArray TClonesArray()
           TClonesArray TClonesArray(const char* classname, Int_t size = 1000, Bool_t call_dtor = kFALSE)
           virtual void ~TClonesArray()
           virtual void AddAfter(TObject*, TObject*)
           virtual void AddAt(TObject*, Int_t)
           virtual void AddAtAndExpand(TObject*, Int_t)
          virtual Int_t AddAtFree(TObject*)
           virtual void AddBefore(TObject*, TObject*)
           virtual void AddFirst(TObject*)
           virtual void AddLast(TObject*)
               TObject* AddrAt(Int_t i)
         static TClass* Class()
           virtual void Clear(Option_t* option)
           virtual void Compress()
           virtual void Delete(Option_t* option)
           virtual void Expand(Int_t newSize)
           virtual void ExpandCreate(Int_t n)
           virtual void ExpandCreateFast(Int_t n)
                TClass* GetClass() const
        virtual TClass* IsA() const
      virtual TObject*& operator[](Int_t i)
       virtual TObject* Remove(TObject* obj)
       virtual TObject* RemoveAt(Int_t idx)
           virtual void ShowMembers(TMemberInspector& insp, char* parent)
           virtual void Sort(Int_t upto = kMaxInt)
           virtual void Streamer(TBuffer& b)
                   void StreamerNVirtual(TBuffer& b)

  Data Members

    protected:

         TClass* fClass  Pointer to the class
      TObjArray* fKeep   Saved copies of pointers to objects

    public:

      static const enum TObject:: kForgetBits  
      static const enum TObject:: kNoSplit     

Class Description

                                                                      
 An array of clone (identical) objects. Memory for the objects        
 stored in the array is allocated only once in the lifetime of the    
 clones array. All objects must be of the same class. For the rest    
 this class has the same properties as TObjArray.                     
                                                                      
 To reduce the very large number of new and delete calls in large     
 loops like this (O(100000) x O(10000) times new/delete):             
                                                                      
   TObjArray a(10000);                                                
   while (TEvent *ev = (TEvent *)next()) {      // O(100000) events   
      for (int i = 0; i < ev->Ntracks; i++) {   // O(10000) tracks    
         a[i] = new TTrack(x,y,z,...);                                
         ...                                                          
         ...                                                          
      }                                                               
      ...                                                             
      a.Delete();                                                     
   }                                                                  
                                                                      
 One better uses a TClonesArray which reduces the number of           
 new/delete calls to only O(10000):                                   
                                                                      
   TCloneArray a("TTrack", 10000);                                    
   while (TEvent *ev = (TEvent *)next()) {      // O(100000) events   
      for (int i = 0; i < ev->Ntracks; i++) {   // O(10000) tracks    
         new(a[i]) TTrack(x,y,z,...);                                 
         ...                                                          
         ...                                                          
      }                                                               
      ...                                                             
      a.Delete();                                                     
   }                                                                  
                                                                      
 Considering that a new/delete costs about 70 mus, O(10^9)            
 new/deletes will save about 19 hours.                                
                                                                      

 Create an array of clone objects of classname. The class must inherit from
 TObject. If the class defines an own operator delete(), make sure that
 it looks like this:

    void MyClass::operator delete(void *vp)
    {
       if ((Long_t) vp != TObject::GetDtorOnly())
          ::operator delete(vp);       // delete space
       else
          TObject::SetDtorOnly(0);
    }

 The third argument is not used anymore and only there for backward
 compatibility reasons.

 Delete a clones array.

 Remove empty slots from array.

 Clear the clones array. Only use this routine when your objects don't
 allocate memory since it will not call the object dtors.

 Clear the clones array. Use this routine when your objects allocate
 memory (e.g. objects inheriting from TNamed or containing TStrings
 allocate memory). If not you better use Clear() since if is faster.

 Expand or shrink the array to newSize elements.

 Expand or shrink the array to n elements and create the clone
 objects by caling their default ctor. If n is less than the current size
 the array is shrinked and the allocated space is freed.
 This routine is typically used to create a clonesarray into which
 one can directly copy object data without going via the
 "new (arr[i]) MyObj()" (i.e. the vtbl is already set correctly).

 Expand or shrink the array to n elements and create the clone
 objects by caling their default ctor. If n is less than the current size
 the array is shrinked and the allocated space is freed.
 This routine is typically used to create a clonesarray into which
 one can directly copy object data without going via the
 "new (arr[i]) MyObj()" (i.e. the vtbl is already set correctly).
 This is a simplified version of ExpandCreate used in the TTree mechanism.

 Remove object at index idx.

 Remove object from array.

 If objects in array are sortable (i.e. IsSortable() returns true
 for all objects) then sort array.

 Write all objects in array to the I/O buffer. ATTENTION: empty slots
 are also stored (using one byte per slot). If you don't want this
 use a TOrdCollection or TList.

Inline Functions

            TClass* GetClass() const
               void AddFirst(TObject*)
               void AddLast(TObject*)
               void AddAt(TObject*, Int_t)
               void AddAtAndExpand(TObject*, Int_t)
              Int_t AddAtFree(TObject*)
               void AddAfter(TObject*, TObject*)
               void AddBefore(TObject*, TObject*)
           TObject* AddrAt(Int_t i)
          TObject*& operator[](Int_t i)
            TClass* Class()
            TClass* IsA() const
               void ShowMembers(TMemberInspector& insp, char* parent)
               void StreamerNVirtual(TBuffer& b)