class DDPG:
"""docstring for DDPG"""
def __init__(self, env):
self.name = 'DDPG' # name for uploading results
self.environment = env
# Randomly initialize actor network and critic network
# with both their target networks
# state_dim = 2, action_dim = 2
self.state_dim = env.observation_space.shape[0]
self.action_dim = env.action_space.shape[0]
self.sess = tf.InteractiveSession()
self.actor_network = ActorNetwork(self.sess, self.state_dim,
self.action_dim)
self.critic_network = CriticNetwork(self.sess, self.state_dim,
self.action_dim)
# initialize replay buffer
self.replay_buffer = ReplayBuffer(REPLAY_BUFFER_SIZE)
# Initialize a random process the Ornstein-Uhlenbeck process for action exploration
self.exploration_noise = OUNoise(self.action_dim)
def train(self):
# print "train step",self.time_step
# Sample a random minibatch of N transitions from replay buffer
minibatch = self.replay_buffer.get_batch(BATCH_SIZE)
state_batch = np.asarray([data[0] for data in minibatch])
action_batch = np.asarray([data[1] for data in minibatch])
reward_batch = np.asarray([data[2] for data in minibatch])
next_state_batch = np.asarray([data[3] for data in minibatch])
done_batch = np.asarray([data[4] for data in minibatch])
# for action_dim = 1
action_batch = np.resize(action_batch, [BATCH_SIZE, self.action_dim])
# Calculate y_batch
next_action_batch = self.actor_network.target_actions(next_state_batch)
q_value_batch = self.critic_network.target_q(next_state_batch,
next_action_batch)
y_batch = []
for i in range(len(minibatch)):
if done_batch[i]:
y_batch.append(reward_batch[i])
else:
y_batch.append(reward_batch[i] + GAMMA * q_value_batch[i])
y_batch = np.resize(y_batch, [BATCH_SIZE, 1])
# Update critic by minimizing the loss L
self.critic_network.train(y_batch, state_batch, action_batch)
# Update the actor policy using the sampled gradient:
action_batch_for_gradients = self.actor_network.actions(state_batch)
q_gradient_batch = self.critic_network.gradients(
state_batch, action_batch_for_gradients)
self.actor_network.train(q_gradient_batch, state_batch)
# Update the target networks
self.actor_network.update_target()
self.critic_network.update_target()
return self.critic_network.q_value(state_batch, action_batch)
def noise_action(self, state):
# Select action a_t according to the current policy and exploration noise
action = self.actor_network.action(state)
return action + self.exploration_noise.noise()
def action(self, state):
action = self.actor_network.action(state)
return action
def perceive(self, state, action, reward, next_state, done):
q_value = 0
# Store transition (s_t,a_t,r_t,s_{t+1}) in replay buffer
self.replay_buffer.add(state, action, reward, next_state, done)
# Store transitions to replay start size then start training
if self.replay_buffer.size() > REPLAY_START_SIZE:
q_value = self.train()
# if self.time_step % 10000 == 0:
# self.actor_network.save_network(self.time_step)
# self.critic_network.save_network(self.time_step)
# Re-iniitialize the random process when an episode ends
if done:
self.exploration_noise.reset()
return q_value
class DDPG:
def __init__(self, env, state_dim=None):
self.name = 'DDPG' # name for uploading results
self.environment = env
# Randomly initialize actor network and critic network
# along with their target networks
if state_dim:
self.state_dim = state_dim
print(self.state_dim)
else:
self.state_dim = env.observation_space.shape[0]
self.action_dim = env.action_space.shape[0]
self.sess = tf.InteractiveSession()
self.actor_network = ActorNetwork(self.sess, self.state_dim,
self.action_dim)
self.critic_network = CriticNetwork(self.sess, self.state_dim,
self.action_dim)
# initialize replay buffer
self.replay_buffer = ReplayBuffer(REPLAY_BUFFER_SIZE)
# Initialize a random process the Ornstein-Uhlenbeck process for action exploration
self.exploration_noise = OUNoise(self.action_dim)
# Flag to signal save
self.not_saved = True
#For normalisation
self.state_mean = 0
self.state_std = 1
self.target_mean = 0
self.target_std = 1
def train(self):
#print "train step",self.time_step
# Sample a random minibatch of N transitions from replay buffer
minibatch = self.replay_buffer.get_batch(BATCH_SIZE)
state_batch = np.asarray([data[0] for data in minibatch])
action_batch = np.asarray([data[1] for data in minibatch])
reward_batch = np.asarray([data[2] for data in minibatch])
next_state_batch = np.asarray([data[3] for data in minibatch])
done_batch = np.asarray([data[4] for data in minibatch])
#For Normalisation
states = np.array(state_batch)
targets = np.array(next_state_batch)
self.state_mean = states.mean(axis=0)
self.state_std = states.std(axis=0) + 0.00000001
self.target_mean = targets.mean(axis=0)
self.target_std = targets.std(axis=0) + 0.00000001
states = (state_batch - self.state_mean) / self.state_std
targets = (next_state_batch - self.target_mean) / self.target_std
state_batch = states.tolist()
next_state_batch = targets.tolist()
# for action_dim = 1
action_batch = np.resize(action_batch, [BATCH_SIZE, self.action_dim])
# Calculate y_batch
next_action_batch = self.actor_network.target_actions(next_state_batch)
q_value_batch = self.critic_network.target_q(next_state_batch,
next_action_batch)
y_batch = []
for i in range(len(minibatch)):
if done_batch[i]:
y_batch.append(reward_batch[i])
else:
y_batch.append(reward_batch[i] + GAMMA * q_value_batch[i])
y_batch = np.resize(y_batch, [BATCH_SIZE, 1])
# Update critic by minimizing the loss L
self.critic_network.train(y_batch, state_batch, action_batch)
# Update the actor policy using the sampled gradient:
action_batch_for_gradients = self.actor_network.actions(state_batch)
q_gradient_batch = self.critic_network.gradients(
state_batch, action_batch_for_gradients)
self.actor_network.train(q_gradient_batch, state_batch)
# Update the target networks
self.actor_network.update_target()
self.critic_network.update_target()
def noise_action(self, state):
# Select action a_t according to the current policy and exploration noise
# Normalising first
state = np.array(state)
state = (state - self.state_mean) / self.state_std
state = state.tolist()
action = self.actor_network.action(state)
# print ("State-: ", state)
# print ("Action-: ", action)
return action + self.exploration_noise.noise()
def action(self, state):
# Normalising first
state = np.array(state)
state = (state - self.state_mean) / self.state_std
state = state.tolist()
# Taking action
action = self.actor_network.action(state)
return action
def perceive(self, state, action, reward, next_state, done, episode):
# Store transition (s_t,a_t,r_t,s_{t+1}) in replay buffer
self.replay_buffer.add(state, action, reward, next_state, done)
# Store transitions to replay start size then start training
if self.replay_buffer.count() > REPLAY_START_SIZE:
self.train()
self.time_step = self.critic_network.time_step
if episode % 20 == 0: #self.time_step % 400 == 0:
if self.not_saved:
self.actor_network.save_network(episode) #(self.time_step)
self.critic_network.save_network(episode) #(self.time_step)
self.not_saved = False
else:
self.not_saved = True
# Re-iniitialize the random process when an episode ends
if done:
self.exploration_noise.reset()