Class: SegmentRuby::ProbabilityDistribution

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

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(total_file_name, data_file_name) ⇒ ProbabilityDistribution

Returns a new instance of ProbabilityDistribution.



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# File 'lib/segment_ruby.rb', line 13

def initialize(total_file_name, data_file_name)
  @total_file_name = total_file_name
  @data_file_name = total_file_name

  @log_total = begin
    total = File.read(total_file_name).to_i
    Math.log2(total)
  rescue
    Math.log2(10**1000)
  end

  @table = Hash.new { |w| -Float::INFINITY }

  File.open(data_file_name).each_line do |line|
    data = line.split(/\s/)
    freq = data[-1].to_i
    keys = data[0..-2]
    key = keys.join(' ')
    log_p = Math.log2(freq) - log_total

    table[key] = log_p
  end
end

Instance Attribute Details

#log_total ⇒ Object (readonly)

Returns the value of attribute log_total.



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# File 'lib/segment_ruby.rb', line 37

def log_total
  @log_total
end

#table ⇒ Object (readonly)

Returns the value of attribute table.



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# File 'lib/segment_ruby.rb', line 37

def table
  @table
end

Instance Method Details

#files ⇒ Object 



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# File 'lib/segment_ruby.rb', line 39

def files
  [@total_file_name, @data_file_name]
end

#has_key?(w) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/segment_ruby.rb', line 55

def has_key?(w)
  table.has_key?(w)
end

#log_prob(w) ⇒ Object 



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# File 'lib/segment_ruby.rb', line 43

def log_prob(w)
  table[w]
end

#prob(w) ⇒ Object 



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# File 'lib/segment_ruby.rb', line 47

def prob(w)
  2**table[w]
end

#total ⇒ Object 



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# File 'lib/segment_ruby.rb', line 51

def total
  2**log_total
end