get_responses.rb

max = 0.0
if !QaCorp.where("question like ?", "%#{self.text}%").empty?
    # Exact question exist in the database.
    answer = QaCorp.where("question like ?", "%#{self.text}%").first.answer
    max = 1.0
else
    corpus = QaCorp.all.map {|qa|  TfIdfSimilarity::Document.new(qa.question)}
    d_question =  TfIdfSimilarity::Document.new(self.text)
    corpus << d_question
    model = TfIdfSimilarity::TfIdfModel.new(corpus, :library => :nmatrix)
    matrix = model.similarity_matrix
    puts "calculating matrix"
    fixed_text = ""
    puts "searching the nearest question-anser pair"
    corpus.each do |doc|
        # score is a number between 0.0 and 1.0
        if d_question.text != doc.text
            score =  matrix[model.document_index(d_question), model.document_index(doc)]
            puts "score is #{score}"
            if score > max      
                max = score
                fixed_text = doc.text
            end
        end
    end 
    if max > 0.7 #make this a hyper parameter for the model
        answer = QaCorp.where("question like ?", "%#{fixed_text}%").first.answer
    else
        answer = nil
    end
end
puts max
answer