Class: VaderSentimentRuby::PunctuationEmphasisAmplifier

Inherits:
Object
  • Object
show all
Defined in:
lib/vader_sentiment_ruby/punctuation_emphasis_amplifier.rb

Overview

Adds emphasis from exclamation points and question marks

Instance Method Summary collapse

Constructor Details

#initialize(text) ⇒ PunctuationEmphasisAmplifier

Returns a new instance of PunctuationEmphasisAmplifier.

Parameters:

  • text (String) 


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# File 'lib/vader_sentiment_ruby/punctuation_emphasis_amplifier.rb', line 7

def initialize(text)
  @text = text
end

Instance Method Details

#amplify_exclamation_points ⇒ Object 



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# File 'lib/vader_sentiment_ruby/punctuation_emphasis_amplifier.rb', line 16

def amplify_exclamation_points
  # check for added emphasis resulting from exclamation points (up to 4 of them)
  ep_count = @text.split('').count('!')
  ep_count = 4.0 if ep_count > 4

  # empirically derived mean sentiment intensity rating increase for exclamation points
  ep_count * 0.292
end

#amplify_question_marks ⇒ Object 



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# File 'lib/vader_sentiment_ruby/punctuation_emphasis_amplifier.rb', line 25

def amplify_question_marks
  # check for added emphasis resulting from question marks (2 or 3+)
  qm_count = @text.split('').count('?')

  return 0.0 unless qm_count > 1
  # empirically derived mean sentiment intensity rating increase for question marks
  return qm_count * 0.18 if qm_count <= 3

  0.96
end

#call ⇒ Float

Returns:

  • (Float) 


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# File 'lib/vader_sentiment_ruby/punctuation_emphasis_amplifier.rb', line 12

def call
  amplify_exclamation_points + amplify_question_marks
end