class MarkovNoodles

Attributes

depth[R]

dictionary[R]

Public Class Methods

new(depth = 2) click to toggle source

# File lib/markov_noodles.rb, line 7
def initialize(depth = 2)
  @depth = depth
  @dictionary = Hash.new { |hash, missing_word| hash[missing_word] = [] }
end

Public Instance Methods

analyse_file(filename) click to toggle source

# File lib/markov_noodles.rb, line 12
def analyse_file(filename)
  analyse_string(File.read(filename))
end

analyse_string(text) click to toggle source

# File lib/markov_noodles.rb, line 16
def analyse_string(text)
  current_words = Array.new(depth)
  text_array = split_text_to_array(text)
  while text_array.length > 0
    next_word = text_array.shift
    add_words(current_words.dup, next_word)
    current_words.push next_word
    current_words.shift
  end
end

generate_n_sentences(n) click to toggle source

# File lib/markov_noodles.rb, line 37
def generate_n_sentences(n)
  n.times.map { generate_sentence }.join(' ')
end

generate_sentence() click to toggle source

# File lib/markov_noodles.rb, line 41
def generate_sentence
  current_words = Array.new(depth)
  sentence_array = []
  loop do
    new_word = current_words.last
    sentence_array.push new_word if new_word
    break if end_word?(new_word)
    next_word_options = @dictionary[current_words]
    if next_word_options.empty? && !end_word?(new_word)
      new_word.concat('.')
      break
    end
    next_word = next_word_options.sample
    current_words.push next_word
    current_words.shift
  end
  sentence_array.join(' ')
end

load_dictionary(filename) click to toggle source

# File lib/markov_noodles.rb, line 33
def load_dictionary(filename)
  @dictionary = MessagePack.unpack(File.read(filename))
end

save_dictionary(filename) click to toggle source

# File lib/markov_noodles.rb, line 27
def save_dictionary(filename)
  File.open(filename, 'w') do |file|
    file.write @dictionary.to_msgpack
  end
end

Private Instance Methods

add_words(preceding, followedby) click to toggle source

# File lib/markov_noodles.rb, line 80
def add_words(preceding, followedby)
  @dictionary[preceding].push followedby
end

end_word?(word) click to toggle source

Checks if word ends with one of following characters .?$

# File lib/markov_noodles.rb, line 85
def end_word?(word)
  !word.nil? && !(word =~ /^*+[?\.!]$/).nil?
end

split_text_to_array(text) click to toggle source

Splits a text into array and inserts @depth nils after each sentence.

This way generated texts can start with any word that is at the beginning of any sentence in analysed text, instead of always starting with the first word from the text.

# File lib/markov_noodles.rb, line 67
def split_text_to_array(text)
  text_array = []
  text.split.each do |word|
    text_array.push word
    if end_word?(word)
      depth.times do
        text_array.push nil
      end
    end
  end
  text_array
end