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https://issues.apache.org/jira/browse/LUCENE-4947?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13638050#comment-13638050
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Kevin Lawson commented on LUCENE-4947:
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bq. Alternatively, can the code be ported away from MDAC to Bricks-automaton,
so it can interact with Lucene's Automaton library? If this is not the case, we
can no longer easily combine wildcards/prefix/fuzzy anymore.
Of course! If you take a look at the tableFuzzySearch() method
[here|https://github.com/klawson88/LevenshteinAutomaton/blob/master/final/src/com/BoxOfC/LevenshteinAutomaton/LevenshteinAutomaton.java],
you'll see that it takes an MDAG (which is equivalent in structure to the
automatons implemented in Brics) and simply transitions it in step with the
LevenshteinAutomaton. The method can be modified easily to accept a Brics
automaton, which i'm assuming has methods that implement typical automaton
actions (namely transitioning and accept state determination).
The main reason one might want to consider using MDAG is that typically
libraries that implement the data structure (which is more widely known as a
DAWG) only support creation with sorted input (and thus, do not allow for
modification). I believe Brics is [no
exception|http://www.brics.dk/automaton/doc/index.html?dk/brics/automaton/Automaton.html].
My MDAG library supports unsorted input and run-time modification of the
structure. (The minor drawback concerning this has been addressed in the
original post).
> Java implementation (and improvement) of Levenshtein & associated lexicon
> automata
> ----------------------------------------------------------------------------------
>
> Key: LUCENE-4947
> URL: https://issues.apache.org/jira/browse/LUCENE-4947
> Project: Lucene - Core
> Issue Type: Improvement
> Affects Versions: 4.0-ALPHA, 4.0-BETA, 4.0, 4.1, 4.2, 4.2.1
> Reporter: Kevin Lawson
>
> I was encouraged by Mike McCandless to open an issue concerning this after I
> contacted him privately about it. Thanks Mike!
> I'd like to submit my Java implementation of the Levenshtein Automaton as a
> homogenous replacement for the current heterogenous, multi-component
> implementation in Lucene.
> Benefits of upgrading include
> - Reduced code complexity
> - Better performance from components that were previously implemented in
> Python
> - Support for on-the-fly dictionary-automaton manipulation (if you wish to
> use my dictionary-automaton implementation)
> The code for all the components is well structured, easy to follow, and
> extensively commented. It has also been fully tested for correct
> functionality and performance.
> The levenshtein automaton implementation (along with the required MDAG
> reference) can be found in my LevenshteinAutomaton Java library here:
> https://github.com/klawson88/LevenshteinAutomaton.
> The minimalistic directed acyclic graph (MDAG) which the automaton code uses
> to store and step through word sets can be found here:
> https://github.com/klawson88/MDAG
> *Transpositions aren't currently implemented. I hope the comment filled,
> editing-friendly code combined with the fact that the section in the Mihov
> paper detailing transpositions is only 2 pages makes adding the functionality
> trivial.
> *As a result of support for on-the-fly manipulation, the MDAG
> (dictionary-automaton) creation process incurs a slight speed penalty. In
> order to have the best of both worlds, i'd recommend the addition of a
> constructor which only takes sorted input. The complete, easy to follow
> pseudo-code for the simple procedure can be found in the first article I
> linked under the references section in the MDAG repository)
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