URI | http://purl.tuc.gr/dl/dias/9648C742-BA07-43D3-8EFD-AB2B212C0CB0 | - |
Αναγνωριστικό | https://www.cse.ust.hk/~yike/enclosure/esa04.pdf | - |
Γλώσσα | en | - |
Μέγεθος | 12 pages | en |
Τίτλος | Optimal external memory planar point enclosure | en |
Δημιουργός | Samoladas Vasilis | en |
Δημιουργός | Σαμολαδας Βασιλης | el |
Δημιουργός | Lars Arge | en |
Δημιουργός | Ke Yi | en |
Περίληψη | In this paper we study the external memory planar point en- closure problem: Given N axis-parallel rectangles in the plane, construct a data structure on disk (an index) such that all K rectangles containing a query point can be reported I/O-efficiently. This problem has important applications in e.g. spatial and temporal databases, and is dual to the important and well-studied orthogonal range searching problem. Surpris- ingly, we show that one cannot construct a linear sized external memory point enclosure data structure that can be used to answer a query in O(logB N + K/B) I/Os, where B is the disk block size. To obtain this bound, Ω(N/B1−ε) disk blocks are needed for some constant ε > 0. With linear space, the best obtainable query bound is O(log2 N + K/B). To show this we prove a general lower bound on the tradeoff between the size of the data structure and its query cost. We also develop a family of structures with matching space and query bounds. | el |
Τύπος | Πλήρης Δημοσίευση σε Συνέδριο | el |
Τύπος | Conference Full Paper | en |
Άδεια Χρήσης | http://creativecommons.org/licenses/by/4.0/ | en |
Ημερομηνία | 2015-10-17 | - |
Ημερομηνία Δημοσίευσης | 2004 | - |
Βιβλιογραφική Αναφορά | L. Arge, V. Samoladas, K. Yi .(2004).Optimal external memory planar point enclosure.Presented at 12th Annual European Symposium.[online].Available: https://www.cse.ust.hk/~yike/enclosure/esa04.pdf | en |