NAME

Lingua::StopWords - Stop words for several languages.

SYNOPSIS

    use Lingua::StopWords qw( getStopWords );
    my $stopwords = getStopWords('en');

    my @words = qw( i am the walrus goo goo g'joob );

    # prints "walrus goo goo g'joob"
    print join ' ', grep { !$stopwords->{$_} } @words;

DESCRIPTION

In keyword search, it is common practice to suppress a collection of "stopwords": words such as "the", "and", "maybe", etc. which exist in in a large number of documents and do not tell you anything important about any document which contains them. This module provides such "stoplists" in several languages.

Supported Languages

    |-----------------------------------------------------------|
    | Language   | ISO code | default encoding | also available |
    |-----------------------------------------------------------|
    | Danish     | da       | ISO-8859-1       | UTF-8          |
    | Dutch      | nl       | ISO-8859-1       | UTF-8          |
    | English    | en       | ISO-8859-1       | UTF-8          |
    | Finnish    | fi       | ISO-8859-1       | UTF-8          |
    | French     | fr       | ISO-8859-1       | UTF-8          |
    | German     | de       | ISO-8859-1       | UTF-8          |
    | Hungarian  | hu       | ISO-8859-2       | UTF-8          |
    | Indonesian | id       | ISO-8859-1       | UTF-8          |
    | Italian    | it       | ISO-8859-1       | UTF-8          |
    | Norwegian  | no       | ISO-8859-1       | UTF-8          |
    | Portuguese | pt       | ISO-8859-1       | UTF-8          |
    | Romanian   | ro       | ISO-8859-2       | UTF-8          |
    | Spanish    | es       | ISO-8859-1       | UTF-8          |
    | Swedish    | sv       | ISO-8859-1       | UTF-8          |
    | Russian    | ru       | KOI8-R           | UTF-8          |
    |-----------------------------------------------------------|

FUNCTIONS

getStopWords

    my $stoplist      = getStopWords('en');
    my $utf8_stoplist = getStopWords('en', 'UTF-8');

Retrieve a stoplist in the form of a hashref where the keys are all stopwords and the values are all 1.

    $stoplist = {
        and => 1,
        if  => 1,
        # ...
    };

getStopWords() expects 1-2 arguments. The first, which is required, is an ISO code representing a supported language. If the ISO code cannot be found, getStopWords returns undef.

The second argument should be 'UTF-8' if you want the stopwords encoded in UTF-8. The UTF-8 flag will be turned on, so make sure you understand all the implications of that.

INSTALLATION

To install this module type the following:

   perl Build.PL
   ./Build
   ./Build test
   ./Build install

SOURCE REPOSITORY

<https://github.com/wollmers/Lingua-StopWords>

AUTHOR

Maintained by Helmut Wollmersdorfer <helmut@wollmersdorfer.at> and Marvin Humphrey <marvin at rectangular dot com>. Original author Fabien Potencier, <fabpot at cpan dot org>.

COPYRIGHT

LICENSE

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself, either Perl version 5.8.3 or, at your option, any later version of Perl 5 you may have available.