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  2. Z-order curve - Wikipedia

    en.wikipedia.org/wiki/Z-order_curve

    The Z-ordering can be used to efficiently build a quadtree (2D) or octree (3D) for a set of points. [4] [5] The basic idea is to sort the input set according to Z-order.Once sorted, the points can either be stored in a binary search tree and used directly, which is called a linear quadtree, [6] or they can be used to build a pointer based quadtree.

  3. Bucket sort - Wikipedia

    en.wikipedia.org/wiki/Bucket_sort

    Bucket sort can be seen as a generalization of counting sort; in fact, if each bucket has size 1 then bucket sort degenerates to counting sort. The variable bucket size of bucket sort allows it to use O( n ) memory instead of O( M ) memory, where M is the number of distinct values; in exchange, it gives up counting sort's O( n + M ) worst-case ...

  4. Map (higher-order function) - Wikipedia

    en.wikipedia.org/wiki/Map_(higher-order_function)

    Map functions can be and often are defined in terms of a fold such as foldr, which means one can do a map-fold fusion: foldr f z . map g is equivalent to foldr (f . g) z. The implementation of map above on singly linked lists is not tail-recursive, so it may build up a lot of frames on the stack when called with a large list. Many languages ...

  5. Comparison sort - Wikipedia

    en.wikipedia.org/wiki/Comparison_sort

    An example is adaptive heap sort, a sorting algorithm based on Cartesian trees. It takes time O ( n log ⁡ k ) {\displaystyle O(n\log k)} , where k {\displaystyle k} is the average, over all values x {\displaystyle x} in the sequence, of the number of times the sequence jumps from below x {\displaystyle x} to above x {\displaystyle x} or vice ...

  6. Schwartzian transform - Wikipedia

    en.wikipedia.org/wiki/Schwartzian_transform

    In computer programming, the Schwartzian transform is a technique used to improve the efficiency of sorting a list of items. This idiom [1] is appropriate for comparison-based sorting when the ordering is actually based on the ordering of a certain property (the key) of the elements, where computing that property is an intensive operation that should be performed a minimal number of times.

  7. MapReduce - Wikipedia

    en.wikipedia.org/wiki/MapReduce

    MapReduce is a programming model and an associated implementation for processing and generating big data sets with a parallel and distributed algorithm on a cluster. [1] [2] [3]A MapReduce program is composed of a map procedure, which performs filtering and sorting (such as sorting students by first name into queues, one queue for each name), and a reduce method, which performs a summary ...

  8. Sorting - Wikipedia

    en.wikipedia.org/wiki/Sorting

    If the sort key values are totally ordered, the sort key defines a weak order of the items: items with the same sort key are equivalent with respect to sorting. See also stable sorting. If different items have different sort key values then this defines a unique order of the items. Workers sorting parcels in a postal facility

  9. Quicksort - Wikipedia

    en.wikipedia.org/wiki/Quicksort

    Recursively sort the "equal to" partition by the next character (key). Given we sort using bytes or words of length W bits, the best case is O(KN) and the worst case O(2 K N) or at least O(N 2) as for standard quicksort, given for unique keys N<2 K, and K is a hidden constant in all standard comparison sort algorithms including