Agrep 0.7.4 - Approximate matching.

Approximate pattern matching allows matches to be approximate, that is, allows the matches to be close to the searched pattern under some measure of closeness. TRE uses the edit-distance measure (also known as the Levenshtein distance) where characters can be inserted, deleted, or substituted in the searched text in order to get an exact match. Each insertion, deletion, or substitution adds the distance, or cost, of the match. TRE can report the matches which have a cost lower than some given threshold value. TRE can also be used to search for matches with the lowest cost.

TRE includes a version of the agrep command line tool for approximate regexp matching in the style of grep. Unlike other agrep implementations (like the one by Sun Wu and Udi Manber from University of Arizona available) TRE agrep allows full regexps of any length, any number of errors, and non-uniform costs for insertion, deletion and substitution.