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  2. Grid (spatial index) - Wikipedia

    en.wikipedia.org/wiki/Grid_(spatial_index)

    The use of such spatial indices is not limited to digital data; the "index" section of any global or street atlas commonly contains a list of named features (towns, streets, etc.) with associated grid square identifiers, and may be considered a perfectly acceptable example of a spatial index (in this case, typically organised by feature name ...

  3. R-tree - Wikipedia

    en.wikipedia.org/wiki/R-tree

    Simple example of an R-tree for 2D rectangles Visualization of an R*-tree for 3D points using ELKI (the cubes are directory pages). R-trees are tree data structures used for spatial access methods, i.e., for indexing multi-dimensional information such as geographical coordinates, rectangles or polygons.

  4. Spatial database - Wikipedia

    en.wikipedia.org/wiki/Spatial_database

    A spatial index is used by a spatial database to optimize spatial queries.Database systems use indices to quickly look up values by sorting data values in a linear (e.g. alphabetical) order; however, this way of indexing data is not optimal for spatial queries in two- or three-dimensional space.

  5. Geohash - Wikipedia

    en.wikipedia.org/wiki/Geohash

    For example, the coordinate pair 57.64911,10.40744 ... For exact latitude and longitude translations Geohash is a spatial index of base 4, ...

  6. Quadtree - Wikipedia

    en.wikipedia.org/wiki/Quadtree

    An example of a recursive binary space partitioning quadtree for a 2D index. Quadtrees may be classified according to the type of data they represent, including areas, points, lines and curves. Quadtrees may also be classified by whether the shape of the tree is independent of the order in which data is processed.

  7. Discrete global grid - Wikipedia

    en.wikipedia.org/wiki/Discrete_global_grid

    The ID is usually used as spatial index (such as internal Quadtree or k-d tree), but is also possible to transform ID into a human-readable label for geocoding applications. Modern databases (e.g. using S2 grid) use also multiple representations for the same data, offering both, a grid (or cell region) based in the Geoid and a grid-based in the ...

  8. Moran's I - Wikipedia

    en.wikipedia.org/wiki/Moran's_I

    The fact that Moran's I is a summation of individual cross products is exploited by the "local indicators of spatial association" (LISA) to evaluate the clustering in those individual units by calculating Local Moran's I for each spatial unit and evaluating the statistical significance for each I i.

  9. PH-tree - Wikipedia

    en.wikipedia.org/wiki/PH-tree

    The PH-tree [1] is a tree data structure used for spatial indexing of multi-dimensional data (keys) such as geographical coordinates, points, feature vectors, rectangles or bounding boxes. The PH-tree is space partitioning index [2] with a structure similar to that of a quadtree or octree. [3]