A Streaming Algorithm for the Convex Hull
نویسندگان
چکیده
We study the 2-center problem with outliers in highdimensional data streams. Given a stream of points in arbitrary d dimensions, the goal is to find two congruent balls of minimum radius covering all but z points. We provide a (1.8 + ε)-approximation streaming algorithm for the problem, improving upon the previous (4 + ε)approximation algorithm available for the problem. The space complexity and update time of our algorithm is poly(d, z, 1ε ), independent of the size of the stream.
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تاریخ انتشار 2015