Purpose

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  The otree class implements the oct tree data structure, used for
  calculating the potential energy of a system of point masses. The
  data structure, and its utility in N body simulations, is discussed
  by Barnes and Hut 1986 (Nature v324 p446).
  The oct tree recursively partitions a 3D cell into 8 subsells. New
  points are added to the tree such that each point corresponds to a
  leaf, and all points are separate from one another.

Modification History

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  July 2010: Written by Chris Beaumont