在本文中,我们将介绍如何使用深度Q网络(DQN)算法实现经典的Flappy Bird游戏。以下是使用Python和TensorFlow库实现的代码示例。
环境搭建
首先,确保你已经安装了以下库:
- TensorFlow
- gym
- numpy
你可以使用以下命令安装这些库:
pip install tensorflow gym numpy
代码示例
以下是一个简单的DQN实现,用于训练Flappy Bird模型。
import gym
import numpy as np
import tensorflow as tf
# 创建环境
env = gym.make('FlappyBird-v0')
# 定义DQN模型
class DQN:
def __init__(self, state_size, action_size):
self.state_size = state_size
self.action_size = action_size
self.memory = []
self.gamma = 0.95 # 折扣因子
self.epsilon = 1.0 # 探索率
self.epsilon_min = 0.01
self.epsilon_decay = 0.995
self.learning_rate = 0.001
self.model = self._build_model()
def _build_model(self):
model = tf.keras.Sequential()
model.add(tf.keras.layers.Dense(24, input_dim=self.state_size, activation='relu'))
model.add(tf.keras.layers.Dense(24, activation='relu'))
model.add(tf.keras.layers.Dense(self.action_size, activation='linear'))
model.compile(loss='mse', optimizer=tf.keras.optimizers.Adam(lr=self.learning_rate))
return model
def remember(self, state, action, reward, next_state, done):
self.memory.append((state, action, reward, next_state, done))
def act(self, state):
if np.random.rand() <= self.epsilon:
return np.random.randint(self.action_size)
act_values = self.model.predict(state)
return np.argmax(act_values[0])
def replay(self, batch_size):
minibatch = random.sample(self.memory, batch_size)
for state, action, reward, next_state, done in minibatch:
target = reward
if not done:
target = (reward + self.gamma * np.amax(self.model.predict(next_state)[0]))
target_f = self.model.predict(state)
target_f[0][action] = target
self.model.fit(state, target_f, epochs=1, verbose=0)
if self.epsilon > self.epsilon_min:
self.epsilon *= self.epsilon_decay
# 训练模型
def train_dqn():
agent = DQN(state_size=4, action_size=2)
episodes = 1000
for e in range(episodes):
state = env.reset()
state = np.reshape(state, [1, state_size])
for time in range(500):
action = agent.act(state)
next_state, reward, done, _ = env.step(action)
next_state = np.reshape(next_state, [1, state_size])
agent.remember(state, action, reward, next_state, done)
state = next_state
if done:
break
agent.replay(32)
if __name__ == "__main__":
train_dqn()
总结
以上代码展示了如何使用DQN算法实现Flappy Bird游戏。通过不断训练,模型将学会如何玩好Flappy Bird游戏。