This is just another TF-IDF calculator for Perl 5.
Quoting Wikipedia:
tf–idf, short for term frequency–inverse document frequency, is a numerical statistic that is intended to reflect how important a word is to a document in a collection or corpus. It is often used as a weighting factor in information retrieval and text mining.
I know that CPAN has several TF-IDF calculator modules already, like Text::TFIDF and Lingua::JA::TFIDF. So why I reinvented the wheel? The reason is language dependency: Text::TFIDF assumes that words in sentence are separated by spaces in spite of that the assumption is not true in most east asian languages. And Lingua::JA::TFIDF works only on documents written in Japanese.
Lingua::TFIDF solves this problem by separating the process into 2 parts: word segmentation and word frequency counting. By supplying a language-specific word segmenter, this class can calculate TF-IDF on documents written in any languages.
#!/usr/bin/env perl
use strict;
use warnings;
use Lingua::TFIDF;
use Lingua::TFIDF::WordSegmenter::SplitBySpace;
my $tf_idf_calc = Lingua::TFIDF->new(
word_segmenter => Lingua::TFIDF::WordSegmenter::SplitBySpace->new,
);
my @documents = (<<'EOD1', <<'EOD2');
Humpty Dumpty sat on a wall,
Humpty Dampty had a great fall.
...
EOD1
Remember, remember, the fifth of November,
The Gunpowder Treason and plot.
...
EOD2
my $tf = $tf_idf_calc->tf(document => $documents[0], normalize => 1);
my $idf = $tf_idf_calc->idf(documents => \@documents);
my $tf_idf = $tf_idf_calc->tf_idf(documents => \@documents, normalize => 1);The MIT License (MIT)
Copyright (c) 2014 Koichi SATOH, all rights reserved.
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