I have a task. By using STL, it can be implemented easily. I am thinking
of moving to Root.
In STL, I use "vector" to store my collection of tracks. then I can
(generic algorithm) "sort" the vector in ascending order of start radius
of tracks.
In Root, How should I do? I noticed that there is a class TObjArray which
can store my tracks. But I am not sure if the method
TObjArray::sort(Int_t upto=kMaxInt) is what I want. 
Thanks for any hint.
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Wensheng Deng                           Phone:     (516) 344-1052
P.O.Box 825                             Fax  :   
Upton, NY 11973, USA                    Email: deng@cnr2.kent.edu
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