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HTML::WordTagRatio::WeightedRatio - Perl module for determining the ratio of words to tags in a range of tokens in an HTML document.


  use HTML::WordTagRatio::WeightedRatio;
  use HTML::Content::HTMLTokenizer;
  use HTML::Content::ContentExtractor;
  my $tokenizer = new HTML::Content::HTMLTokenizer('TAG','WORD');
  my $doc = join("",<HTML>);
  my ($word_count_arr_ref,$tag_count_arr_ref,$token_type_arr_ref,$token_hash_ref) = $tokenizer->Tokenize($doc);
  my $ratio = new HTML::WordTagRatio::WeightedRatio();
  my $value = $ratio->RangeValue(0, @$word_count_arr_ref, 
                                $word_count_arr_ref, $tag_count_arr_ref);


HTML::WordTagRatio::WeightedRatio computes a ratio of Words to Tags for a given range. In psuedo code, the ratio is

Words^2/(Words + Tags)


  • my $ratio = new HTML::WordTagRatio::WeightedRatio()

    Initializes HTML::WordTagRatio::WeightedRatio

  • my $value = $ratio->RangeValue($start, $end, \@WordCount, \@TagCount)

    $value is computed as follows:

            ($WordCount[$end] - $WordCount[$start])**2/(($WordCount[$end] - $WordCount[$start]) + ($TagCount[$end] - $TagCount[$start]))

    This is the number of words in the range squared, divided by the total number of tags in range. $WordCount[$i] is the number of word tokens before or at the ith token in the input HTML document. $TagCount[$i] is the number of tag tokens before or at the ith token in the input HTML document.


Jean Tavernier (


Copyright 2005 Jean Tavernier. All rights reserved.

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

SEE ALSO (1), HTML::Content::HTMLTokenizer (3), HTML::Content::ContentExtractor (3), HTML::WordTagRatio::Ratio (3), HTML::WordTagRatio::SmoothedRatio (3), HTML::WordTagRatio::RelativeRatio (3), HTML::WordTagRatio::ExponentialRatio (3), HTML::WordTagRatio::NormalizedRatio (3).