Abstract
In this paper we describe some of the hierarchical methods that have been used to produce computationally efficient algorithms for the calculation of the mutual interactions of a collection of n particles. The work required for such calculations grows quadratically as the number of particles. In this paper we survey the so called "tree codes" or "hierarchical" methods which provide accurate approximations of the required interactions, but for which the computational work is $O(n$ log $n)$ for "simple" hierarchical methods, and $O$(n) for the more sophisticated Fast Multipo!e method. This survey paper follows closely the article by Greengard ["Numerical Solution of the N-Body Problem", Computers in Physics, 1990].
Information
