Movatterモバイル変換


[0]ホーム

URL:


Jump to content
WikipediaThe Free Encyclopedia
Search

Priority R-tree

From Wikipedia, the free encyclopedia

ThePriority R-tree is aworst-case asymptotically optimal alternative to thespatialtreeR-tree. It was first proposed by Arge, De Berg, Haverkort and Yi, K. in an article from 2004.[1] The prioritized R-tree is essentially a hybrid between ak-dimensional tree and aR-tree in that it defines a given object's N-dimensionalbounding volume (called Minimum Bounding Rectangles – MBR) as apoint in N-dimensions, represented by the ordered pair of the rectangles. The termprioritized arrives from the introduction of four priority-leaves that represents the most extreme values of each dimensions, included in every branch of the tree. Before answering awindow-query by traversing the sub-branches, the prioritized R-tree first checks for overlap in its priority nodes. The sub-branches are traversed (and constructed) by checking whether the least value of the first dimension of the query is above the value of the sub-branches. This gives access to a quick indexation by the value of the first dimension of the bounding box.

Performance

[edit]

Argeet al. writes that the priority tree always answers window-queries withO((NB)11d+TB){\displaystyle O\left(\left({\frac {N}{B}}\right)^{1-{\frac {1}{d}}}+{\frac {T}{B}}\right)} I/Os, where N is the number of d-dimensional (hyper-) rectangles stored in the R-tree, B is the disk block size, and T is the output size.

Dimensions

[edit]

In the case ofd=2{\displaystyle d=2} the rectangle is represented by((xmin,ymin),(xmax,ymax)){\displaystyle \,((x_{min},y_{min}),(x_{max},y_{max}))} and the MBR thus four corners(xmin,ymin,xmax,ymax){\displaystyle \,(x_{min},y_{min},x_{max},y_{max})}.

See also

[edit]

References

[edit]
  1. ^L. Arge; M. de Berg; H. J. Haverkort; K. Yi (2004)."The Priority R-Tree: A Practically Efficient and Worst-Case Optimal R-Tree"(PDF). SIGMOD. Retrieved12 October 2011.
Search trees
(dynamic sets,
associative arrays)
Heaps
Tries
Spatial data
partitioning trees
Other trees
Stub icon

Thisalgorithms ordata structures-related article is astub. You can help Wikipedia byadding missing information.

Retrieved from "https://en.wikipedia.org/w/index.php?title=Priority_R-tree&oldid=1225956499"
Categories:
Hidden category:

[8]ページ先頭

©2009-2026 Movatter.jp