What?

Given a set of strings from different languages, build a detector for the majority language (often, but not necessarily, English). More information on the algorithm here.

Example

training_sentences = File.readlines("datasets/gutenberg-training.txt")
detector = LanguageDetector.new(:ngram_size => 3)
detector.train(30, training_sentences)

puts "Testing on English sentences..."
true_english = 0
false_spanish = 0
IO.foreach("datasets/gutenberg-test-en.txt") do |line|
  next if line.strip.empty?
  if detector.classify(line) == "majority"
    true_english += 1
  else
    puts line
    false_spanish += 1    
  end
end
puts false_spanish
puts true_english

Using the Gem

gem install unsupervised-language-detection

require 'rubygems'
require 'unsupervised-language-detection'

UnsupervisedLanguageDetection.is_english_tweet?("I am an English sentence.") # => true
UnsupervisedLanguageDetection.is_english_tweet?("Hola, me llamo Edwin.") # => false

Demo

See a demo here.