When.com Web Search

Search results

  1. Results From The WOW.Com Content Network
  2. Move-to-front transform - Wikipedia

    en.wikipedia.org/wiki/Move-to-front_transform

    The move-to-front (MTF) transform is an encoding of data (typically a stream of bytes) designed to improve the performance of entropy encoding techniques of compression.When efficiently implemented, it is fast enough that its benefits usually justify including it as an extra step in data compression algorithm.

  3. Inversion (discrete mathematics) - Wikipedia

    en.wikipedia.org/wiki/Inversion_(discrete...

    An inversion may be denoted by the pair of places (2, 4) or the pair of elements (5, 2). The inversions of this permutation using element-based notation are: (3, 1), (3, 2), (5, 1), (5, 2), and (5,4). In computer science and discrete mathematics, an inversion in a sequence is a pair of elements that are out of their natural order.

  4. Comparison of programming languages (associative array)

    en.wikipedia.org/wiki/Comparison_of_programming...

    The user can search for elements in an associative array, and delete elements from the array. The following shows how multi-dimensional associative arrays can be simulated in standard AWK using concatenation and the built-in string-separator variable SUBSEP:

  5. Category of preordered sets - Wikipedia

    en.wikipedia.org/wiki/Category_of_preordered_sets

    It can be made into a preordered set itself by the pointwise relation: (f ≤ g) ⇔ (∀x f(x) ≤ g(x)) This preordered set can in turn be considered as a category, which makes Ord a 2-category (the additional axioms of a 2-category trivially hold because any equation of parallel morphisms is true in a posetal category).

  6. Symmetric difference - Wikipedia

    en.wikipedia.org/wiki/Symmetric_difference

    The power set of any set becomes an abelian group under the operation of symmetric difference, with the empty set as the neutral element of the group and every element in this group being its own inverse. The power set of any set becomes a Boolean ring, with symmetric difference as the addition of the ring and intersection as the multiplication ...

  7. Bit-reversal permutation - Wikipedia

    en.wikipedia.org/wiki/Bit-reversal_permutation

    A Hammersley set whose coordinates are the integers from 0 to 255 and their bit-reversals In applied mathematics, a bit-reversal permutation is a permutation of a sequence of n {\displaystyle n} items, where n = 2 k {\displaystyle n=2^{k}} is a power of two .

  8. Brent's method - Wikipedia

    en.wikipedia.org/wiki/Brent's_method

    The idea to combine the bisection method with the secant method goes back to Dekker (1969).. Suppose that we want to solve the equation f(x) = 0.As with the bisection method, we need to initialize Dekker's method with two points, say a 0 and b 0, such that f(a 0) and f(b 0) have opposite signs.

  9. Computational complexity of mathematical operations - Wikipedia

    en.wikipedia.org/wiki/Computational_complexity...

    The complexity of an elementary function is equivalent to that of its inverse, since all elementary functions are analytic and hence invertible by means of Newton's method. In particular, if either exp {\displaystyle \exp } or log {\displaystyle \log } in the complex domain can be computed with some complexity, then that complexity is ...