#decayed_learning_rate = learning_rate *
# decay_rate ^ (global_step / decay_steps)
# u can use help(tf.train.exponential_decay) in python3 to see the manual of this function
global_step = tf.Variable(0)
learning_rate = tf.train.exponential_decay(0.1, global_step, 100, 0.96, staircase=True)
#生成學(xué)習(xí)率
learning_step = tf.train.GradientDescentOptimizer(learning_rate).minimize(.....,
global_step=global_step)
#使用指數(shù)衰減學(xué)習(xí)率 每次 sess.run(train), the global_step will increase 1,
#You dont need change the global_step in trainng loop
