Sat Jul 23 19:41:19 2022

neural_network_test():
  Demonstrate back propagation.
  Graphics saved as "neural_network.png"
  Initial cost =  5.455896973386748
  Final cost   =  0.0009381370898689703

neural_network_test():
  Normal end of execution.
Sat Jul 23 19:45:47 2022