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Introduction

The Levenshtein Python C extension module contains functions for fast computation of

• Levenshtein (edit) distance, and edit operations

• string similarity

• approximate median strings, and generally string averaging

• string sequence and set similarity

It supports both normal and Unicode strings.

Python 2.2 or newer is required; Python 3 is supported.

StringMatcher.py is an example SequenceMatcher-like class built on the top of Levenshtein. It misses some SequenceMatcher's functionality, and has some extra OTOH.

Levenshtein.c can be used as a pure C library, too. You only have to define NOPYTHON preprocessor symbol (-DNOPYTHON) when compiling it. The functionality is similar to that of the Python extension. No separate docs are provided yet, RTFS. But they are not interchangeable:

• C functions exported when compiling with -DNO_PYTHON (see Levenshtein.h) are not exported when compiling as a Python extension (and vice versa)

• Unicode character type used with -DNOPYTHON is wchart, Python extension uses Py_UNICODE, they may be the same but don't count on it

Documentation

gendoc.sh generates HTML API documentation, you probably want a selfcontained instead of includable version, so run in ./gendoc.sh --selfcontained. It needs Levenshtein already installed and genextdoc.py.

License

Levenshtein can be copied and/or modified under the terms of GNU General Public License, see the file COPYING for full license text.

History

This package was long missing from PyPi and available as source checkout only. We needed to restore this package for Go Mobile for Plone <http://webandmobile.mfabrik.com>_ and Pywurfl <http://celljam.net/>_ projects which depend on this.

Source code

• http://github.com/ztane/python-Levenshtein/

Documentation

• Documentation for the current version <https://rawgit.com/ztane/python-Levenshtein/master/docs/Levenshtein.html>_

Authors

• Maintainer: Antti Haapala <[email protected]>

• Python 3 compatibility: Esa Mtt

• Jonatas CD: Fixed documentation generation

• Previous maintainer: Mikko Ohtamaa <http://opensourcehacker.com>_

• Original code: David Necas (Yeti)

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Changelog

0.12.0

• Fixed a bug in StringMatcher.StringMatcher.getmatchingblocks / extract_editops for Python 3; now allow only str editops on both Python 2 and Python 3, for simpler and working code.

• Added documentation in the source distribution and in GIT

• Fixed the package layout: renamed the .so/.dll to _levenshtein, and made it reside inside a package, along with the StringMatcher class.

• Fixed spelling errors.

0.11.2

• Fixed a bug in setup.py: installation would fail on Python 3 if the locale did not specify UTF-8 charset (Felix Yan).

• Added COPYING, StringMatcher.py, gendoc.sh and NEWS in MANIFEST.in, as they were missing from source distributions.

0.11.1

• Added Levenshtein.h to MANIFEST.in

0.11.0

• Python 3 support, maintainership passed to Antti Haapala

0.10.1 - 0.10.2

• Made python-Lehvenstein Git compatible and use setuptools for PyPi upload

• Created HISTORY.txt and made README reST compatible