A rectangle is the spatial region associated with an R-tree node. Its corners come from the minimum and maximum value of each coordinate among the points in that node’s subtree; in higher dimensions, it becomes a hyper-rectangle. section 10.2.2
R-tree rectangles serve two related purposes:
- A leaf rectangle is the smallest axis-aligned rectangle containing every point stored in that leaf. section 10.2.2
- An internal-node rectangle is the smallest axis-aligned rectangle containing the bounding rectangles of all its children. section 10.2.2
City-map regions
For points representing cities, an R-tree groups nearby points under bounding rectangles. A parent rectangle encloses the rectangles of its child groups, creating a hierarchy over the Cartesian plane.
