Agrep

Template:Lowercase {{#invoke:Infobox|infobox}}Template:Template other {{#invoke:Check for unknown parameters|check|unknown=Template:Main other|preview=Page using Template:Infobox software with unknown parameter "_VALUE_"|ignoreblank=y| AsOf | author | background | bodystyle | caption | collapsetext | collapsible | developer | discontinued | engine | engines | genre | included with | language | language count | language footnote | latest preview date | latest preview version | latest release date | latest release version | latest_preview_date | latest_preview_version | latest_release_date | latest_release_version | licence | license | logo | logo alt | logo caption | logo class | logo size | logo title | logo upright | logo_alt | logo_caption | logo_class | logo_size | logo_title | logo_upright | middleware | module | name | operating system | operating_system | other_names | platform | programming language | programming_language | qid | released | replaced_by | replaces | repo | screenshot | screenshot alt | screenshot class | screenshot size | screenshot title | screenshot upright | screenshot_alt | screenshot_class | screenshot_size | screenshot_upright | service_name | size | standard | title | ver layout | website }}Template:Main other agrep (approximate grep) is an open-source approximate string matching program, developed by Udi Manber and Sun Wu between 1988 and 1991,<ref>Template:Cite conference</ref> for use with the Unix operating system. It was later ported to OS/2, DOS, and Windows.

It selects the best-suited algorithm for the current query from a variety of the known fastest (built-in) string searching algorithms, including Manber and Wu's bitap algorithm based on Levenshtein distances.

agrep is also the search engine in the indexer program GLIMPSE. agrep is under a free ISC License.<ref>WebGlimpse, Glimpse and also AGREP license since 18.09.2014 (ISC License).</ref>

Alternative implementations

A more recent agrep is the command-line tool provided with the TRE regular expression library. TRE agrep is more powerful than Wu-Manber agrep since it allows weights and total costs to be assigned separately to individual groups in the pattern. It can also handle Unicode.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> Unlike Wu-Manber agrep, TRE agrep is licensed under a 2-clause BSD-like license.

FREJ (Fuzzy Regular Expressions for Java) open-source library provides command-line interface which could be used in the way similar to agrep. Unlike agrep or TRE it could be used for constructing complex substitutions for matched text.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> However its syntax and matching abilities differs significantly from ones of ordinary regular expressions.

See also

• Bitap algorithm
• TRE (computing)

External links

• Wu-Manber agrep
  • AGREP home page
  • For Unix (To compile under OSX 10.8, add -Wno-return-type to the CFLAGs = -O line in the Makefile)
• See also
  • TRE regexp matching package
  • cgrep a defunct command line approximate string matching tool
  • nrgrep a command line approximate string matching tool
  • agrep as implemented in R