# File lib/ai4r/som/two_phase_layer.rb, line 36
      def initialize(nodes, learning_rate = 0.9, phase_one = 150, phase_two = 100,
              phase_one_learning_rate = 0.1, phase_two_learning_rate = 0)
        super nodes, nodes, phase_one + phase_two, learning_rate
        @phase_one = phase_one
        @phase_two = phase_two
        @lr = @initial_learning_rate

        @phase_one_learning_rate = phase_one_learning_rate
        @phase_two_learning_rate = phase_two_learning_rate

        @radius_reduction = @phase_one / (nodes/2.0 - 1) + 1
        @delta_lr = (@lr - @phase_one_learning_rate)/ @phase_one
        @radius = (nodes / 2.0).to_i
      end