levenshtein-distance
Levenshtein Distance Algorithm better than O(n*m)?
Are you interested in reducing the time complexity or the space complexity ? The average time complexity can be reduced O(n + d^2), where n is the length of the longer string and d is the edit distance. If you are only interested in the edit distance and not interested in reconstructing the edit sequence, … Read more
Finding closest neighbour using optimized Levenshtein Algorithm
I’ve done it a number of times. The way I do it is with a recursive depth-first tree-walk of the game tree of possible changes. There is a budget k of changes, that I use to prune the tree. With that routine in hand, first I run it with k=0, then k=1, then k=2 until … Read more
String similarity metrics in Python [duplicate]
I realize it’s not the same thing, but this is close enough: >>> import difflib >>> a=”Hello, All you people” >>> b = ‘hello, all You peopl’ >>> seq=difflib.SequenceMatcher(a=a.lower(), b=b.lower()) >>> seq.ratio() 0.97560975609756095 You can make this as a function def similar(seq1, seq2): return difflib.SequenceMatcher(a=seq1.lower(), b=seq2.lower()).ratio() > 0.9 >>> similar(a, b) True >>> similar(‘Hello, world’, … Read more
High performance fuzzy string comparison in Python, use Levenshtein or difflib [closed]
In case you’re interested in a quick visual comparison of Levenshtein and Difflib similarity, I calculated both for ~2.3 million book titles: import codecs, difflib, Levenshtein, distance with codecs.open(“titles.tsv”,”r”,”utf-8″) as f: title_list = f.read().split(“\n”)[:-1] for row in title_list: sr = row.lower().split(“\t”) diffl = difflib.SequenceMatcher(None, sr[3], sr[4]).ratio() lev = Levenshtein.ratio(sr[3], sr[4]) sor = 1 – distance.sorensen(sr[3], … Read more
Sort an array by the “Levenshtein Distance” with best performance in Javascript
I wrote an inline spell checker a few years ago and implemented a Levenshtein algorithm – since it was inline and for IE8 I did quite a lot of performance optimisation. var levDist = function(s, t) { var d = []; //2d matrix // Step 1 var n = s.length; var m = t.length; if … Read more
What algorithm gives suggestions in a spell checker?
There is good essay by Peter Norvig how to implement a spelling corrector. It’s basicly a brute force approach trying candidate strings with a given edit distance. (Here are some tips how you can improve the spelling corrector performance using a Bloom Filter and faster candidate hashing.) The requirements for a spell checker are weaker. … Read more
Levenshtein: MySQL + PHP
You need a levenshtein function in MySQL and query like $word = mysql_real_escape_string($word); mysql_qery(“SELECT `term` FROM `words` WHERE levenshtein(‘$word’, `term`) BETWEEN 0 AND 4”);
How to add levenshtein function in mysql?
I have connected to my MySQL server and simply executed this statement in MySQL Workbench, and it simply worked – I now have new function levenshtein(). For example, this works as expected: SELECT levenshtein(‘abcde’, ‘abced’) 2