1Lingua::StopWords(3pm)User Contributed Perl DocumentationLingua::StopWords(3pm)
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6 Lingua::StopWords - Stop words for several languages.
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9 use Lingua::StopWords qw( getStopWords );
10 my $stopwords = getStopWords('en');
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12 my @words = qw( i am the walrus goo goo g'joob );
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14 # prints "walrus goo goo g'joob"
15 print join ' ', grep { !$stopwords->{$_} } @words;
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18 In keyword search, it is common practice to suppress a collection of
19 "stopwords": words such as "the", "and", "maybe", etc. which exist in
20 in a large number of documents and do not tell you anything important
21 about any document which contains them. This module provides such
22 "stoplists" in several languages.
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24 Supported Languages
25 |-----------------------------------------------------------|
26 | Language | ISO code | default encoding | also available |
27 |-----------------------------------------------------------|
28 | Danish | da | ISO-8859-1 | UTF-8 |
29 | Dutch | nl | ISO-8859-1 | UTF-8 |
30 | English | en | ISO-8859-1 | UTF-8 |
31 | Finnish | fi | ISO-8859-1 | UTF-8 |
32 | French | fr | ISO-8859-1 | UTF-8 |
33 | German | de | ISO-8859-1 | UTF-8 |
34 | Hungarian | hu | ISO-8859-2 | UTF-8 |
35 | Indonesian | id | ISO-8859-1 | UTF-8 |
36 | Italian | it | ISO-8859-1 | UTF-8 |
37 | Norwegian | no | ISO-8859-1 | UTF-8 |
38 | Portuguese | pt | ISO-8859-1 | UTF-8 |
39 | Romanian | ro | ISO-8859-2 | UTF-8 |
40 | Spanish | es | ISO-8859-1 | UTF-8 |
41 | Swedish | sv | ISO-8859-1 | UTF-8 |
42 | Russian | ru | KOI8-R | UTF-8 |
43 |-----------------------------------------------------------|
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46 getStopWords
47 my $stoplist = getStopWords('en');
48 my $utf8_stoplist = getStopWords('en', 'UTF-8');
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50 Retrieve a stoplist in the form of a hashref where the keys are all
51 stopwords and the values are all 1.
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53 $stoplist = {
54 and => 1,
55 if => 1,
56 # ...
57 };
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59 getStopWords() expects 1-2 arguments. The first, which is required, is
60 an ISO code representing a supported language. If the ISO code cannot
61 be found, getStopWords returns undef.
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63 The second argument should be 'UTF-8' if you want the stopwords encoded
64 in UTF-8. The UTF-8 flag will be turned on, so make sure you
65 understand all the implications of that.
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68 To install this module type the following:
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70 perl Build.PL
71 ./Build
72 ./Build test
73 ./Build install
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76 The stoplists supplied by this module were created as part of the
77 Snowball project (see <http://snowball.tartarus.org>,
78 Lingua::Stem::Snowball).
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80 Lingua::EN::StopWords provides a different stoplist for English.
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83 <https://github.com/wollmers/Lingua-StopWords>
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86 Maintained by Helmut Wollmersdorfer <helmut@wollmersdorfer.at> and
87 Marvin Humphrey <marvin at rectangular dot com>. Original author
88 Fabien Potencier, <fabpot at cpan dot org>.
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91 Copyright 2021 Helmut Wollmersdorfer Copyright 2004-2008 Fabien
92 Potencier, Marvin Humphrey
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95 This library is free software; you can redistribute it and/or modify it
96 under the same terms as Perl itself, either Perl version 5.8.3 or, at
97 your option, any later version of Perl 5 you may have available.
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101perl v5.34.0 2022-01-21 Lingua::StopWords(3pm)