Class: MarkovGenerator

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

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(n, genmax) ⇒ MarkovGenerator

Returns a new instance of MarkovGenerator.



6
7
8
9
10
11
 
# File 'lib/text_generator.rb', line 6

def initialize(n, genmax)
  @size = n
  @ngrams = {}
  @genmax = genmax
  @beginnings = []
end

Instance Attribute Details

#beginnings ⇒ Object

Returns the value of attribute beginnings.



4
5
6
 
# File 'lib/text_generator.rb', line 4

def beginnings
  @beginnings
end

#genmax ⇒ Object

Returns the value of attribute genmax.



4
5
6
 
# File 'lib/text_generator.rb', line 4

def genmax
  @genmax
end

#ngrams ⇒ Object

Returns the value of attribute ngrams.



4
5
6
 
# File 'lib/text_generator.rb', line 4

def ngrams
  @ngrams
end

Instance Method Details

#feed(line) ⇒ Object 



17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
 
# File 'lib/text_generator.rb', line 17

def feed(line)
  tokens = tokenize(line)

  return if tokens.length < @size

  @beginnings << tokens[0..@size-1]

  (0..(tokens.length - @size)).each do |i|
    ngram = tokens[i..i+@size-1].to_a 
    next_gram = [tokens[i+@size]]
    if @ngrams.has_key? ngram
      @ngrams[ngram] << next_gram 
    else
      @ngrams[ngram] = next_gram
    end
  end
end

#generate ⇒ Object 



35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
 
# File 'lib/text_generator.rb', line 35

def generate
  current = @beginnings.sample
  output = current.to_a
  while output.length <= @genmax-1
    if @ngrams.has_key? current
      possible_next = @ngrams[current].flatten
      next_gram = possible_next.sample
      output << next_gram
      current = output.last(@size)
    else
      break
    end
  end
  return output.join(" ")
end

#tokenize(line) ⇒ Object 



13
14
15
 
# File 'lib/text_generator.rb', line 13

def tokenize(line)
  line.strip.split(" ")
end