From 042a3e2353e366cc1e571078fd92c7365fe12d46 Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Fri, 22 Jan 2016 12:29:07 -0500 Subject: [PATCH] Improve levenshtein() docs. Fix chars-vs-bytes confusion here too. Improve poor grammar and markup. --- doc/src/sgml/fuzzystrmatch.sgml | 17 +++++++++++------ 1 file changed, 11 insertions(+), 6 deletions(-) diff --git a/doc/src/sgml/fuzzystrmatch.sgml b/doc/src/sgml/fuzzystrmatch.sgml index f26bd90dfc..feb06861da 100644 --- a/doc/src/sgml/fuzzystrmatch.sgml +++ b/doc/src/sgml/fuzzystrmatch.sgml @@ -106,15 +106,20 @@ levenshtein_less_equal(text source, text target, int max_d) returns int Both source and target can be any - non-null string, with a maximum of 255 bytes. The cost parameters + non-null string, with a maximum of 255 characters. The cost parameters specify how much to charge for a character insertion, deletion, or substitution, respectively. You can omit the cost parameters, as in the second version of the function; in that case they all default to 1. - levenshtein_less_equal is accelerated version of - levenshtein function for low values of distance. If actual distance - is less or equal then max_d, then levenshtein_less_equal - returns accurate value of it. Otherwise this function returns value - which is greater than max_d. + + + + levenshtein_less_equal is an accelerated version of the + Levenshtein function for use when only small distances are of interest. + If the actual distance is less than or equal to max_d, + then levenshtein_less_equal returns the correct + distance; otherwise it returns some value greater than max_d. + If max_d is negative then the behavior is the same as + levenshtein.