# File lib/ai4r/clusterers/single_linkage.rb, line 89 def create_distance_matrix(data_set) @distance_matrix = Array.new(data_set.data_items.length-1) {|index| Array.new(index+1)} data_set.data_items.each_with_index do |a, i| i.times do |j| b = data_set.data_items[j] @distance_matrix[i-1][j] = @distance_function.call(a, b) end end end