NAME

    Text::Levenshtein::BV - Bit Vector (BV) implementation of the
    Levenshtein Algorithm

SYNOPSIS

      use Text::Levenshtein::BV;
    
      my $lev = Text::Levenshtein::BV->new;
      my $ses = $lev->SES(\@a,\@b);

ABSTRACT

    Text::Levenshtein::BV implements the Levenshtein algorithm using bit
    vectors and is faster in most cases than the naive implementation using
    a match matrix.

DESCRIPTION

 CONSTRUCTOR

    new()

      Creates a new object which maintains internal storage areas for the
      SES computation. Use one of these per concurrent SES() call.

 METHODS

    SES(\@a,\@b)

      Finds a Shortest Edit Script (SES), taking two arrayrefs as method
      arguments. It returns an array reference of corresponding indices,
      which are represented by 2-element array refs.

    distance(\@a,\@b)

      Calculates the edit distance, taking two arrayrefs as method
      arguments. It returns an integer.

    hunks2sequences(\@alignment)

      Reformats the alignment returned by SES into an array of two
      sequences.

    sequence2char(\@a)

      Renders an array of strings into a string.

    sequences2hunks(\@a,\@b)

      Does the reverse of method hunks2sequences.

    hunks2char(\@a,\@b,\@alignment)

      Returns hunks of aligned characters.

    hunks2distance(\@a,\@b,\@alignment)

      Calculates the distance from alignment.

 EXPORT

    None by design.

STABILITY

    Until release of version 1.00 the included methods, names of methods
    and their interfaces are subject to change.

    Beginning with version 1.00 the specification will be stable, i.e. not
    changed between major versions.

REFERENCES

    [Hyy03] Hyyrö, Heikki. (2003). A Bit-Vector Algorithm for Computing
    Levenshtein and Damerau Edit Distances. In Nord. J. Comput. 10. 29-39.

    [Hyy04a] Hyyrö, Heikki. (2004). A Note on Bit-Parallel Alignment
    Computation. In M. Simanek and J. Holub, editors, Stringology, pages
    79-87. Department of Computer Science and Engineering, Faculty of
    Electrical Engineering, Czech Technical University, 2004.

    [Hyy04b] Hyyrö, Heikki. (2004). Bit-parallel LCS-length computation
    revisited. In Proc. 15th Australasian Workshop on Combinatorial
    Algorithms (AWOCA 2004), 2004.

    [HN02] Hyyrö, Heikki and Navarro, Gonzalo. Faster bit-parallel
    approximate string matching. In Proc. 13th Combinatorial Pattern
    Matching (CPM 2002), LNCS 2373, pages 203–224, 2002.

    [Myers99] Myers, Gene. A fast bit-vector algorithm for approximate
    string matching based on dynamic progamming. Journal of the ACM,
    46(3):395–415, 1999.

SEE ALSO

    Text::Levenshtein

SOURCE REPOSITORY

    http://github.com/wollmers/Text-Levenshtein-BV

AUTHOR

    Helmut Wollmersdorfer <helmut@wollmersdorfer.at>

COPYRIGHT AND LICENSE

    Copyright 2016-2022 by Helmut Wollmersdorfer

    This library is free software; you can redistribute it and/or modify it
    under the same terms as Perl itself.