def __init__(self, env, params):
self.env = env
params.actions = env.actions()
self.num_actions = env.actions()
self.episodes = params.episodes
self.steps = params.steps
self.train_steps = params.train_steps
self.update_freq = params.update_freq
self.save_weights = params.save_weights
self.history_length = params.history_length
self.discount = params.discount
self.eps = params.init_eps
self.eps_delta = (params.init_eps - params.final_eps) / params.final_eps_frame
self.replay_start_size = params.replay_start_size
self.eps_endt = params.final_eps_frame
self.random_starts = params.random_starts
self.batch_size = params.batch_size
self.ckpt_file = params.ckpt_dir+'/'+params.game
self.global_step = tf.Variable(0, trainable=False)
if params.lr_anneal:
self.lr = tf.train.exponential_decay(params.lr, self.global_step, params.lr_anneal, 0.96, staircase=True)
else:
self.lr = params.lr
self.buffer = Buffer(params)
self.memory = Memory(params.size, self.batch_size)
with tf.variable_scope("train") as self.train_scope:
self.train_net = ConvNet(params, trainable=True)
with tf.variable_scope("target") as self.target_scope:
self.target_net = ConvNet(params, trainable=False)
self.optimizer = tf.train.RMSPropOptimizer(self.lr, params.decay_rate, 0.0, self.eps)
self.actions = tf.placeholder(tf.float32, [None, self.num_actions])
self.q_target = tf.placeholder(tf.float32, [None])
self.q_train = tf.reduce_max(tf.mul(self.train_net.y, self.actions), reduction_indices=1)
self.diff = tf.sub(self.q_target, self.q_train)
half = tf.constant(0.5)
if params.clip_delta > 0:
abs_diff = tf.abs(self.diff)
clipped_diff = tf.clip_by_value(abs_diff, 0, 1)
linear_part = abs_diff - clipped_diff
quadratic_part = tf.square(clipped_diff)
self.diff_square = tf.mul(half, tf.add(quadratic_part, linear_part))
else:
self.diff_square = tf.mul(half, tf.square(self.diff))
if params.accumulator == 'sum':
self.loss = tf.reduce_sum(self.diff_square)
else:
self.loss = tf.reduce_mean(self.diff_square)
# backprop with RMS loss
self.task = self.optimizer.minimize(self.loss, global_step=self.global_step)
class DQN:
def __init__(self, env, params):
self.env = env
params.actions = env.actions()
self.num_actions = env.actions()
self.episodes = params.episodes
self.steps = params.steps
self.train_steps = params.train_steps
self.update_freq = params.update_freq
self.save_weights = params.save_weights
self.history_length = params.history_length
self.discount = params.discount
self.eps = params.init_eps
self.eps_delta = (params.init_eps - params.final_eps) / params.final_eps_frame
self.replay_start_size = params.replay_start_size
self.eps_endt = params.final_eps_frame
self.random_starts = params.random_starts
self.batch_size = params.batch_size
self.ckpt_file = params.ckpt_dir+'/'+params.game
self.global_step = tf.Variable(0, trainable=False)
if params.lr_anneal:
self.lr = tf.train.exponential_decay(params.lr, self.global_step, params.lr_anneal, 0.96, staircase=True)
else:
self.lr = params.lr
self.buffer = Buffer(params)
self.memory = Memory(params.size, self.batch_size)
with tf.variable_scope("train") as self.train_scope:
self.train_net = ConvNet(params, trainable=True)
with tf.variable_scope("target") as self.target_scope:
self.target_net = ConvNet(params, trainable=False)
self.optimizer = tf.train.RMSPropOptimizer(self.lr, params.decay_rate, 0.0, self.eps)
self.actions = tf.placeholder(tf.float32, [None, self.num_actions])
self.q_target = tf.placeholder(tf.float32, [None])
self.q_train = tf.reduce_max(tf.mul(self.train_net.y, self.actions), reduction_indices=1)
self.diff = tf.sub(self.q_target, self.q_train)
half = tf.constant(0.5)
if params.clip_delta > 0:
abs_diff = tf.abs(self.diff)
clipped_diff = tf.clip_by_value(abs_diff, 0, 1)
linear_part = abs_diff - clipped_diff
quadratic_part = tf.square(clipped_diff)
self.diff_square = tf.mul(half, tf.add(quadratic_part, linear_part))
else:
self.diff_square = tf.mul(half, tf.square(self.diff))
if params.accumulator == 'sum':
self.loss = tf.reduce_sum(self.diff_square)
else:
self.loss = tf.reduce_mean(self.diff_square)
# backprop with RMS loss
self.task = self.optimizer.minimize(self.loss, global_step=self.global_step)
def randomRestart(self):
self.env.restart()
for _ in range(self.random_starts):
action = rand.randrange(self.num_actions)
reward = self.env.act(action)
state = self.env.getScreen()
terminal = self.env.isTerminal()
self.buffer.add(state)
if terminal:
self.env.restart()
def trainEps(self, train_step):
if train_step < self.eps_endt:
return self.eps - train_step * self.eps_delta
else:
return self.eps_endt
def observe(self, exploration_rate):
if rand.random() < exploration_rate:
a = rand.randrange(self.num_actions)
else:
x = self.buffer.getInput()
action_values = self.train_net.y.eval( feed_dict={ self.train_net.x: x } )
a = np.argmax(action_values)
state = self.buffer.getState()
action = np.zeros(self.num_actions)
action[a] = 1.0
reward = self.env.act(a)
screen = self.env.getScreen()
self.buffer.add(screen)
next_state = self.buffer.getState()
terminal = self.env.isTerminal()
self.memory.add(state, action, reward, next_state, terminal)
return state, action, reward, next_state, terminal
def doMinibatch(self, sess, successes, failures):
batch = self.memory.getSample()
state = np.array([batch[i][0] for i in range(self.batch_size)]).astype(np.float32)
actions = np.array([batch[i][1] for i in range(self.batch_size)]).astype(np.float32)
rewards = np.array([batch[i][2] for i in range(self.batch_size)]).astype(np.float32)
successes += np.sum(rewards==1)
failures += np.sum(rewards==-1)
next_state = np.array([batch[i][3] for i in range(self.batch_size)]).astype(np.float32)
terminals = np.array([batch[i][4] for i in range(self.batch_size)]).astype(np.float32)
rewards = np.clip(rewards, -1.0, 1.0)
q_target = self.target_net.y.eval( feed_dict={ self.target_net.x: next_state } )
q_target_max = np.argmax(q_target, axis=1)
q_target = rewards + ((1.0 - terminals) * (self.discount * q_target_max))
(result, loss) = sess.run( [self.task, self.loss],
feed_dict={ self.q_target: q_target,
self.train_net.x: state,
self.actions: actions } )
return successes, failures, loss
def play(self):
self.randomRestart()
self.env.restart()
for i in xrange(self.episodes):
terminal = False
while not terminal:
action, reward, screen, terminal = self.observe(self.eps)
def copy_weights(self, sess):
for key in self.train_net.weights.keys():
t_key = 'target/' + key.split('/', 1)[1]
sess.run(self.target_net.weights[t_key].assign(self.train_net.weights[key]))
def save(self, saver, sess, step):
saver.save(sess, self.ckpt_file, global_step=step)
def restore(self, saver):
ckpt = tf.train.get_checkpoint_state(self.ckpt_file)
if ckpt and ckpt.model_checkpoint_path:
saver.restore(sess, ckpt.model_checkpoint_path)
