# File lib/ai4r/neural_network/backpropagation.rb, line 224 def calculate_output_deltas(expected_values) output_values = @activation_nodes.last output_deltas = [] output_values.each_index do |output_index| error = expected_values[output_index] - output_values[output_index] output_deltas << @derivative_propagation_function.call( output_values[output_index]) * error end @deltas = [output_deltas] end