Computing the k Nearest-Neighbors for all Vertices via Dijkstra

Sariel Har-Peled

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arXiv · 1607.07818

Computing the k Nearest-Neighbors for all Vertices via Dijkstra

Sariel Har-Peled

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Abstract

We are given a directed graph $G = (V,E)$ with $n$ vertices and $m$ edges, with positive weights on the edges, and a parameter $k >0$. We show how to compute, for every vertex $v \in V$, its $k$ nearest-neighbors. The algorithm runs in $O( k ( n \log n + m ) )$ time, and follows by a somewhat careful modification of Dijkstra's shortest path algorithm. This result is probably folklore, but we were unable to find a reference to it -- thus, this note.

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Sariel Har-Peled. 2016-07-26. Computing the k Nearest-Neighbors for all Vertices via Dijkstra. https://arxiv.org/abs/1607.07818

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