When.com Web Search

Search results

  1. Results From The WOW.Com Content Network
  2. Regular expression - Wikipedia

    en.wikipedia.org/wiki/Regular_expression

    A regular expression (shortened as regex or regexp), [1] sometimes referred to as rational expression, [2] [3] is a sequence of characters that specifies a match pattern in text. Usually such patterns are used by string-searching algorithms for "find" or "find and replace" operations on strings , or for input validation .

  3. Comparison of regular expression engines - Wikipedia

    en.wikipedia.org/wiki/Comparison_of_regular...

    Ruby 1.8, Ruby 1.9, and Ruby 2.0 and later versions use different engines; Ruby 1.9 integrates Oniguruma, Ruby 2.0 and later integrate Onigmo, a fork from Oniguruma. Rust: docs.rs: MIT License: The primary regex crate does not allow look-around expressions. There is an Oniguruma binding called onig that does. SAP ABAP: SAP.com: Proprietary: Tcl ...

  4. Thompson's construction - Wikipedia

    en.wikipedia.org/wiki/Thompson's_construction

    In computer science, Thompson's construction algorithm, also called the McNaughton–Yamada–Thompson algorithm, [1] is a method of transforming a regular expression into an equivalent nondeterministic finite automaton (NFA). [2] This NFA can be used to match strings against the regular expression.

  5. Parsing expression grammar - Wikipedia

    en.wikipedia.org/wiki/Parsing_expression_grammar

    A parsing expression is a kind of pattern that each string may either match or not match.In case of a match, there is a unique prefix of the string (which may be the whole string, the empty string, or something in between) which has been consumed by the parsing expression; this prefix is what one would usually think of as having matched the expression.

  6. de Bruijn sequence - Wikipedia

    en.wikipedia.org/wiki/De_Bruijn_sequence

    Goal: to construct a B(2, 4) de Bruijn sequence of length 2 4 = 16 using Eulerian (n − 1 = 4 − 1 = 3) 3-D de Bruijn graph cycle. Each edge in this 3-dimensional de Bruijn graph corresponds to a sequence of four digits: the three digits that label the vertex that the edge is leaving followed by the one that labels the edge.

  7. Check digit - Wikipedia

    en.wikipedia.org/wiki/Check_digit

    The digit the farthest to the right (which is multiplied by 1) is the check digit, chosen to make the sum correct. It may need to have the value 10, which is represented as the letter X. For example, take the ISBN 0-201-53082-1: The sum of products is 0×10 + 2×9 + 0×8 + 1×7 + 5×6 + 3×5 + 0×4 + 8×3 + 2×2 + 1×1 = 99 ≡ 0 (mod 11). So ...

  8. Python (programming language) - Wikipedia

    en.wikipedia.org/wiki/Python_(programming_language)

    Since 7 October 2024, Python 3.13 is the latest stable release, and it and, for few more months, 3.12 are the only releases with active support including for bug fixes (as opposed to just for security) and Python 3.9, [55] is the oldest supported version of Python (albeit in the 'security support' phase), due to Python 3.8 reaching end-of-life.

  9. Newton's method - Wikipedia

    en.wikipedia.org/wiki/Newton's_method

    An illustration of Newton's method. In numerical analysis, the Newton–Raphson method, also known simply as Newton's method, named after Isaac Newton and Joseph Raphson, is a root-finding algorithm which produces successively better approximations to the roots (or zeroes) of a real-valued function.