Summary: I/O­Efficient Dynamic Planar Point Location
(Extended Abstract)
Lars Arge \Lambda Jan Vahrenhold y
Abstract
We present the first provably I/O­efficient dynamic data
structure for point location in a general planar subdivision.
Our structure uses O(N=B) disk blocks to store a subdivi­
sion of size N , where B is the disk block size. Queries can
be answered in O(log 2
B N) I/Os in the worst­case, and in­
sertions and deletions can be performed in O(log 2
B N) and
O(log B N) I/Os amortized, respectively. Previously, an I/O­
efficient dynamic point location structure was only known
for monotone subdivisions. Part of our data structure is
based on a new external version of the so­called logarith­
mic method which allows for efficient dynamization of static
external­memory data structures with certain characteris­
tics. We believe that this method could prove helpful in the
dynamization of other external memory structures.

Source: Arge, Lars - Department of Computer Science, Aarhus Universitet

Collections: Computer Technologies and Information Sciences