A sweep line algorithm for nearest neighbour queries
نویسندگان
چکیده
We introduce a novel algorithm for solving the nearest neighbour problem when the query points are known in advance, which is based on Fortune’s plane sweep algorithm. The crucial idea is to use the wavefront for solving the nearest neighbour queries as the Voronoi diagram is being computed, instead of storing it in an auxiliary data structure, as the algorithm presented by Lee and Yang [9] does, and then querying that data structure. Although our algorithm is not optimal in terms of its worst-case behaviour, it runs in O(m logm) expected time, where m is the total number of points (sites and query points). Experimental results show that it outperforms the algorithm of Lee and Yang, provided the number of query points does not exceed four times the number of sites.
منابع مشابه
A Sweep Line Algorithm for Multiple Nearest Neighbour Queries
We introduce a novel algorithm for solving the nearest neighbour problem when the query points are known in advance, which is based on Fortune’s plane sweep algorithm. The crucial idea is to use the wavefront for solving the nearest neighbour queries as the Voronoi diagram is being computed, instead of storing it in an auxiliary data structure, as the algorithm presented by Lee and Yang does, a...
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