因此,我使用的是使用Tensorflow的deepQ实现来解决CartPole-v0,但是有时输出(占所有运行的40%)停留在9。我尝试使用tf.set_random_seed修复种子,但仍不能确保不会卡住输出。这是我的代码:
from collections import deque
import tensorflow as tf
import numpy as np
import random
import gym
import matplotlib.pyplot as plt
import pickle
from time import time
t = int(time())
class DQNAgent:
def __init__(self, state_size, action_size):
self.state_size = state_size
self.action_size = action_size
self.memory = deque(maxlen = 2000)
self.gamma = 0.95
#self.epsilon = 1.0
#self.epsilon_min = 0.01
#self.epsilon_decay = 0.995
self.learning_rate = 0.001
self.model = self._build_model()
def _build_model(self):
graph = tf.Graph()
with graph.as_default():
inp = tf.placeholder(tf.float32, [None, self.state_size])
out = tf.placeholder(tf.float32, [None, self.action_size])
w1 = tf.Variable(tf.truncated_normal([self.state_size, 24]))
b1 = tf.Variable(tf.zeros([24]))
hidden = tf.nn.tanh(tf.matmul(inp, w1) + b1)
w2 = tf.Variable(tf.truncated_normal([24, 24]))
b2 = tf.Variable(tf.zeros([24]))
hidden1 = tf.nn.tanh(tf.matmul(hidden, w2) + b2)
w3 = tf.Variable(tf.truncated_normal([24, 24]))
b3 = tf.Variable(tf.zeros([24]))
hidden2 = tf.nn.tanh(tf.matmul(hidden1, w3) + b3)
wo = tf.Variable(tf.truncated_normal([24, self.action_size]))
bo = tf.Variable(tf.zeros([self.action_size]))
prediction = tf.matmul(hidden2, wo) + bo
loss = tf.losses.mean_squared_error(out, prediction)
train = tf.train.AdamOptimizer().minimize(loss)
init = tf.global_variables_initializer()
return graph, inp, out, prediction, train, init
def remember(self, state, action, reward, next_state, done):
self.memory.append((state, action, reward, next_state, done))
def act(self, state, sess):
act_values = sess.run(self.model[3], feed_dict = { self.model[1]: state})
return np.argmax(act_values[0])
def replay(self, batch_size, sess):
try:
minibatch = random.sample(self.memory, batch_size)
except ValueError:
minibatch = self.memory
for state, action, reward, next_state, done in minibatch:
target = reward
if not done:
target = reward + self.gamma * np.amax(sess.run(self.model[3], feed_dict = { self.model[1]: next_state}))
target_f = sess.run(self.model[3], feed_dict = { self.model[1]: state})
target_f[0][action] = target
#print(target_f)
sess.run(self.model[4], feed_dict = { self.model[1]: state, self.model[2]: target_f})
if __name__ == "__main__":
environment = 'CartPole-v0'
env = gym.make(environment)
avgs = deque(maxlen = 50)
rewardLA = []
agent = DQNAgent(env.observation_space.shape[0], env.action_space.n)
sess = tf.Session(graph = agent.model[0])
sess.run(agent.model[5])
episodes = 10000
rewardL = []
for e in range(episodes):
state = env.reset()
state = np.reshape(state, [1, 4])
for time_t in range(500):
#env.render()
action = agent.act(state, sess)
next_state, reward, done, _ = env.step(action)
next_state = np.reshape(next_state, [1, 4])
agent.remember(state, action, reward, next_state, done)
state = next_state
if done:
break
avgs.append(time_t)
rewardLA.append(sum(avgs)/len(avgs))
print("episode: ", e, "score: ", time_t)
rewardL.append(time_t)
agent.replay(32, sess)
#pickle.dump(rewardL, open(environment + "_" + str(t) + "_rewardL.pickle", "wb"))
plt.plot(rewardLA)
plt.show()
我尝试将optimiser更改为GD,rmsProp,但是没有任何效果,但是如果我只是重新启动代码,它会更好(在200个时期内达到199)。为什么会这样呢?我如何解决它。
最佳答案
查看您的代码,我看不到如何探索环境。您是否不需要像epsilon greedy这样的东西来确保探索发生?例如,我尝试如下修改agent.act()
方法,看来可以解决问题。
def act(self, state, sess, episode):
if random.random() < math.pow(2, -episode / 30):
return env.action_space.sample()
act_values = sess.run(self.model[3], feed_dict = { self.model[1]: state})
return np.argmax(act_values[0])
尝试使用30,由于缺乏更好的用语,我将其称为“探索常数”。
无论如何,在我看来,没有像epsilon greedy这样的东西(或者像上面那样随时间衰减的东西),您就依靠神经网络输出具有足够的熵来引起足够的探索。有时可能是这种情况;其他时候没有。