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arXiv · 1203.6266

Circle separability queries in logarithmic time

Greg Aloupis·Luis Barba·Stefan Langerman
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Abstract

Let $P$ be a set of $n$ points in the plane. In this paper we study a new variant of the circular separability problem in which a point set $P$ is preprocessed so that one can quickly answer queries of the following form: Given a geometric object $Q$, report the minimum circle containing $P$ and exluding $Q$. Our data structure can be constructed in $O(n\log n)$ time using O(n) space, and can be used to answer the query when $Q$ is either a circle or a convex $m$-gon in $O(\log n)$ or $O(\log n + \log m)$ time, respectively.

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Greg Aloupis, Luis Barba, Stefan Langerman. 2012-03-28. Circle separability queries in logarithmic time. https://arxiv.org/abs/1203.6266

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