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. Hadamard matrix - Wikipedia

    en.wikipedia.org/wiki/Hadamard_matrix

    Two Hadamard matrices are considered equivalent if one can be obtained from the other by negating rows or columns, or by interchanging rows or columns. Up to equivalence, there is a unique Hadamard matrix of orders 1, 2, 4, 8, and 12. There are 5 inequivalent matrices of order 16, 3 of order 20, 60 of order 24, and 487 of order 28.

  4. Rodrigues' rotation formula - Wikipedia

    en.wikipedia.org/wiki/Rodrigues'_rotation_formula

    For the inverse mapping, see log map from SO(3) to (). The Hodge dual of the rotation R {\displaystyle \mathbf {R} } is just R ∗ = − sin ⁡ ( θ ) k {\displaystyle \mathbf {R} ^{*}=-\sin(\theta )\mathbf {k} } which enables the extraction of both the axis of rotation and the sine of the angle of the rotation from the rotation matrix itself ...

  5. Object–relational database - Wikipedia

    en.wikipedia.org/wiki/Object–relational_database

    An object–relational database (ORD), or object–relational database management system (ORDBMS), is a database management system (DBMS) similar to a relational database, but with an object-oriented database model: objects, classes and inheritance are directly supported in database schemas and in the query language.

  6. Burrows–Wheeler transform - Wikipedia

    en.wikipedia.org/wiki/Burrows–Wheeler_transform

    The Burrows–Wheeler transform (BWT, also called block-sorting compression) rearranges a character string into runs of similar characters. This is useful for compression, since it tends to be easy to compress a string that has runs of repeated characters by techniques such as move-to-front transform and run-length encoding.

  7. Latent semantic analysis - Wikipedia

    en.wikipedia.org/wiki/Latent_semantic_analysis

    The probabilistic model of LSA does not match observed data: LSA assumes that words and documents form a joint Gaussian model (ergodic hypothesis), while a Poisson distribution has been observed. Thus, a newer alternative is probabilistic latent semantic analysis, based on a multinomial model, which is reported to give better results than ...

  8. Inverse iteration - Wikipedia

    en.wikipedia.org/wiki/Inverse_iteration

    In numerical analysis, inverse iteration (also known as the inverse power method) is an iterative eigenvalue algorithm. It allows one to find an approximate eigenvector when an approximation to a corresponding eigenvalue is already known. The method is conceptually similar to the power method. It appears to have originally been developed to ...

  9. Square matrix - Wikipedia

    en.wikipedia.org/wiki/Square_matrix

    In mathematics, a square matrix is a matrix with the same number of rows and columns. An n-by-n matrix is known as a square matrix of order . Any two square matrices of the same order can be added and multiplied. Square matrices are often used to represent simple linear transformations, such as shearing or rotation.