String::Ediff - Produce common sub-string indices for two strings
use String::Ediff; my $s1 = "hello world"; my $s2 = "hxello worlyd"; my $indices = String::Ediff::ediff($s1, $s2); print $indices, "\n"; #1 10 0 0 2 11 0 0 # 0 1 2 0 1 2 # 01234567890123456789012345 012345678901234567890123 print String::Ediff::ediff("hello world a hello world", "hxello worlyd xyz hello"); # 1 10 0 0 2 11 0 0 13 20 0 0 17 23 0 0
This module uses suffix tree algorithm to determine the common substrings.
$common_sub_string_indices = ediff($s1, $s2);
The ediff method takes two strings and returns the common sub-string indices between the two strings. The returned indices consists of records separated by a space. Each record, representing one common sub-string, consists of 8 numbers in the following format:
bc1 ec1 bl1 el1 bc2 ec2 bl2 el2
bc1 - begin char in s1
ec1 - end char in s1
bl1 - begin line in s1
el1 - end line in s1
bc2 - begin char in s2
ec2 - end char in s2
bl2 - begin line in s2
el2 - end line in s2
1. white spaces are ignored. 2. because of white spaces are ignored, the end char index of a previous record and the begin char index of a next record might overlap. 3. the interval is right open-ended, i.e. [1, 4) means char 1, 2, and 3 are in the common string. char 4 is not. 4. only sub-string with size >= 4 are recorded.
Bo Zou, email@example.com
Copyright (C) 2003-2005 Bo Zou
This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.