On the number of range queries in k-space
نویسنده
چکیده
A range query on a set of points in a k-dimensional coordinate space asks for all points lying within a hyperrectangle specified by ranges of permissible values for each of the coordinates. In this paper we regard as identical any two range queries which return the same set of points. We then Investigate the number of range queries possible on a set—given a set of N points in k-space, what Is the maximum number of distinct subsets that may be specified by giving bounding hyperrectangles. The bounds we find for this number (as a function of N and k) are substantial improvements over previous results, and tighten a lower bound on the time required to process range queries. This work was supported by the Office of Naval Research under contract N00014-76-C-0370. University Libraries Carnegie Mellon University" Pittsburgh PA 15213-3890 Table of
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عنوان ژورنال:
- Discrete Applied Mathematics
دوره 1 شماره
صفحات -
تاریخ انتشار 1979