enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Oniguruma - Wikipedia

    en.wikipedia.org/wiki/Oniguruma

    Oniguruma (鬼車) is a free and open-source regular expression library that supports a variety of character encodings, written by K. Kosako.The Ruby programming language, in version 1.9, as well as PHP's multi-byte string module (since PHP5), use Oniguruma as their regular expression engine. [2]

  3. Approximate string matching - Wikipedia

    en.wikipedia.org/wiki/Approximate_string_matching

    Different approximate matchers impose different constraints. Some matchers use a single global unweighted cost, that is, the total number of primitive operations necessary to convert the match to the pattern. For example, if the pattern is coil, foil differs by one substitution, coils by one insertion, oil by one deletion, and foal by two ...

  4. Thompson's construction - Wikipedia

    en.wikipedia.org/wiki/Thompson's_construction

    The algorithm works recursively by splitting an expression into its constituent subexpressions, from which the NFA will be constructed using a set of rules. [3] More precisely, from a regular expression E, the obtained automaton A with the transition function Δ [clarification needed] respects the following properties:

  5. 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 .

  6. Pattern matching - Wikipedia

    en.wikipedia.org/wiki/Pattern_matching

    In many programming languages, a particular syntax of strings is used to represent regular expressions, which are patterns describing string characters. However, it is possible to perform some string pattern matching within the same framework that has been discussed throughout this article.

  7. grep - Wikipedia

    en.wikipedia.org/wiki/Grep

    The pcregrep command is an implementation of grep that uses Perl regular expression syntax. [17] Similar functionality can be invoked in the GNU version of grep with the -P flag. [18] Ports of grep (within Cygwin and GnuWin32, for example) also run under Microsoft Windows. Some versions of Windows feature the similar qgrep or findstr command. [19]

  8. String-searching algorithm - Wikipedia

    en.wikipedia.org/wiki/String-searching_algorithm

    A basic example of string searching is when the pattern and the searched text are arrays of elements of an alphabet Σ. Σ may be a human language alphabet, for example, the letters A through Z and other applications may use a binary alphabet (Σ = {0,1}) or a DNA alphabet (Σ = {A,C,G,T}) in bioinformatics .

  9. Rabin–Karp algorithm - Wikipedia

    en.wikipedia.org/wiki/Rabin–Karp_algorithm

    However, it is a useful algorithm for multiple pattern search. To find any of a large number, say k, fixed length patterns in a text, a simple variant of the Rabin–Karp algorithm uses a Bloom filter or a set data structure to check whether the hash of a given string belongs to a set of hash values of patterns we are looking for: