data structures - Could anyone tell me what's the difference between KD-tree and R-tree -


i @ definition of kd-tree , r-tree, seems same.

could tell me what's difference between kd-tree , r-tree? thanks

r-trees , kd-trees based on similar ideas (space partitioning based on axis-aligned regions), key differences are:

  • nodes in kd-trees represent separating planes, whereas nodes in r-trees represent bounding boxes.
  • kd-trees partition whole of space regions whereas r-trees partition subset of space containing points of interest.
  • kd-trees represent disjoint partition (points belong 1 region) whereas regions in r-tree may overlap.

(there lots of similar kinds of tree structures partitioning space: quadtrees, bsp-trees, r*-trees, etc. etc.)


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