Class: Entropic::NGramCounter

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

Overview

Public: a counter for ngrams

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(size) ⇒ NGramCounter

Returns a new instance of NGramCounter.



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# File 'lib/entropic.rb', line 29

def initialize(size)
  @size = size
  @counts = Hash.new(0)
  @total = 0
end

Instance Attribute Details

#counts ⇒ Object

Returns the value of attribute counts.



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# File 'lib/entropic.rb', line 28

def counts
  @counts
end

#size ⇒ Object

Returns the value of attribute size.



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# File 'lib/entropic.rb', line 28

def size
  @size
end

#total ⇒ Object

Returns the value of attribute total.



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# File 'lib/entropic.rb', line 28

def total
  @total
end

Instance Method Details

#count(ngram, if_not_found) ⇒ Object

Public: get count for string, with default

Examples

counter = NGramCounter.new(2) counter.update(‘01234’) counter.count(‘01’, 0) #=> 1 counter.count(‘bob, 0) #=> 0

ngram: The String to check if_not_found : what to update with



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# File 'lib/entropic.rb', line 79

def count(ngram, if_not_found)
  @counts.fetch(ngram, if_not_found)
end

#update(string) ⇒ Object

Public: update a counter with a string, with a multiplier of 1

Examples

counter = NGramCounter.new(2) counter.update(‘01234’)

string: The String to update with



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# File 'lib/entropic.rb', line 61

def update(string)
  update_with_multiplier(string, 1)
end

#update_with_multiplier(string, multiplier) ⇒ Object

Public: update a counter with a string, and a multiplier

Examples

counter = NGramCounter.new(2) counter.update_with_multiplier(‘01234’, 1)

string: The String to update with multiplier: The Integer describing how much weight (will often be 1)



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# File 'lib/entropic.rb', line 45

def update_with_multiplier(string, multiplier)
  Entropic.sliding(string, @size).each do |ngram|
    @counts[ngram] += multiplier
    @total += multiplier
  end
end