def update(self, experiences, errors_out=None):
"""Update the model from experiences
This function is thread-safe.
Args:
experiences (list): list of dict that contains
state: cupy.ndarray or numpy.ndarray
action: int [0, n_action_types)
reward: float32
next_state: cupy.ndarray or numpy.ndarray
next_legal_actions: list of booleans; True means legal
gamma (float): discount factor
Returns:
None
"""
exp_batch = batch_experiences(experiences,
xp=self.xp,
phi=self.phi,
batch_states=self.batch_states)
loss = self._compute_loss(exp_batch, self.gamma, errors_out=errors_out)
# Update stats
self.average_loss *= self.average_loss_decay
self.average_loss += (1 - self.average_loss_decay) * float(loss.data)
self.optimizer.zero_grads()
loss.backward()
self.optimizer.update()
def update(self, experiences, errors_out=None):
"""Update the model from experiences"""
batch = batch_experiences(experiences, self.xp, self.phi, self.gamma)
self.update_q_func(batch)
self.update_policy_and_temperature(batch)
self.sync_target_network()
def test_batch_experiences(self):
experiences = []
experiences.append(
[dict(state=1, action=1, reward=1, next_state=i,
next_action=1, is_state_terminal=False) for i in range(3)])
experiences.append([dict(state=1, action=1, reward=1, next_state=1,
next_action=1, is_state_terminal=False)])
four_step_transition = [dict(
state=1, action=1, reward=1, next_state=1,
next_action=1, is_state_terminal=False)] * 3
four_step_transition.append(dict(
state=1, action=1, reward=1, next_state=5,
next_action=1, is_state_terminal=True))
experiences.append(four_step_transition)
batch = replay_buffer.batch_experiences(
experiences, np, lambda x: x, 0.99)
self.assertEqual(batch['state'][0], 1)
self.assertSequenceEqual(list(batch['is_state_terminal']),
list(np.asarray([0.0, 0.0, 1.0],
dtype=np.float32)))
self.assertSequenceEqual(list(batch['discount']),
list(np.asarray([
0.99 ** 3, 0.99 ** 1, 0.99 ** 4],
dtype=np.float32)))
self.assertSequenceEqual(list(batch['next_state']),
list(np.asarray([2, 1, 5])))
def update_from_episodes(self, episodes, errors_out=None):
has_weights = isinstance(episodes, tuple)
if has_weights:
episodes, weights = episodes
if errors_out is None:
errors_out = []
if errors_out is None:
errors_out_step = None
else:
del errors_out[:]
for _ in episodes:
errors_out.append(0.0)
errors_out_step = []
with state_reset(self.model), state_reset(self.target_model):
loss = 0
tmp = list(reversed(sorted(
enumerate(episodes), key=lambda x: len(x[1]))))
sorted_episodes = [elem[1] for elem in tmp]
indices = [elem[0] for elem in tmp] # argsort
max_epi_len = len(sorted_episodes[0])
for i in range(max_epi_len):
transitions = []
weights_step = []
for ep, index in zip(sorted_episodes, indices):
if len(ep) <= i:
break
transitions.append([ep[i]])
if has_weights:
weights_step.append(weights[index])
batch = batch_experiences(
transitions,
xp=self.xp,
phi=self.phi,
gamma=self.gamma,
batch_states=self.batch_states)
assert len(batch['state']) == len(transitions)
if i == 0:
self.input_initial_batch_to_target_model(batch)
if has_weights:
batch['weights'] = self.xp.asarray(
weights_step, dtype=self.xp.float32)
loss += self._compute_loss(batch,
errors_out=errors_out_step)
if errors_out is not None:
for err, index in zip(errors_out_step, indices):
errors_out[index] += err
loss /= max_epi_len
# Update stats
self.average_loss *= self.average_loss_decay
self.average_loss += \
(1 - self.average_loss_decay) * float(loss.array)
self.model.cleargrads()
loss.backward()
self.optimizer.update()
if has_weights:
self.replay_buffer.update_errors(errors_out)
def update(self, experiences, errors_out=None):
"""Update the model from experiences"""
batch = batch_experiences(experiences, self.xp, self.phi, self.gamma)
self.update_q_func(batch)
if self.q_func1_optimizer.t % self.policy_update_delay == 0:
self.update_policy(batch)
self.sync_target_network()
def update(self, experiences, errors_out=None):
"""Update the model from experiences"""
batch = batch_experiences(experiences, self.xp, self.phi, self.gamma)
if self.obs_normalizer:
batch['state'] = self.obs_normalizer(batch['state'], update=False)
batch['next_state'] = self.obs_normalizer(batch['next_state'],
update=False)
self.critic_optimizer.update(lambda: self.compute_critic_loss(batch))
self.actor_optimizer.update(lambda: self.compute_actor_loss(batch))
def extra_update(agent, all_experiences):
for epoch in range(args.cpo_distill_epochs):
n_samples = len(all_experiences)
indices = np.asarray(range(n_samples))
np.random.shuffle(indices)
for start_idx in (range(0, n_samples,
args.cpo_distill_batch_size)):
batch_idx = indices[start_idx:start_idx +
args.cpo_distill_batch_size].astype(
np.int32)
experiences = [all_experiences[idx] for idx in batch_idx]
batch = batch_experiences(experiences, agent.xp, agent.phi,
agent.gamma)
agent.update_policy_and_temperature(batch)
def update_from_episodes(self, episodes, errors_out=None):
# Sort episodes desc by their lengths
sorted_episodes = list(reversed(sorted(episodes, key=len)))
max_epi_len = len(sorted_episodes[0])
# Precompute all the input batches
batches = []
for i in range(max_epi_len):
transitions = []
for ep in sorted_episodes:
if len(ep) <= i:
break
transitions.append([ep[i]])
batch = batch_experiences(transitions,
xp=self.xp,
phi=self.phi,
gamma=self.gamma)
if self.obs_normalizer:
batch['state'] = self.obs_normalizer(batch['state'],
update=False)
batch['next_state'] = self.obs_normalizer(batch['state'],
update=False)
batches.append(batch)
with self.model.state_reset(), self.target_model.state_reset():
# Since the target model is evaluated one-step ahead,
# its internal states need to be updated
self.target_q_function.update_state(batches[0]['state'],
batches[0]['action'])
self.target_policy(batches[0]['state'])
# Update critic through time
critic_loss = 0
for batch in batches:
critic_loss += self.compute_critic_loss(batch)
self.critic_optimizer.update(lambda: critic_loss / max_epi_len)
with self.model.state_reset():
# Update actor through time
actor_loss = 0
for batch in batches:
actor_loss += self.compute_actor_loss(batch)
self.actor_optimizer.update(lambda: actor_loss / max_epi_len)
def update(self, experiences, errors_out=None):
"""Update the model from experiences
Args:
experiences (list): List of lists of dicts.
For DQN, each dict must contains:
- state (object): State
- action (object): Action
- reward (float): Reward
- is_state_terminal (bool): True iff next state is terminal
- next_state (object): Next state
- weight (float, optional): Weight coefficient. It can be
used for importance sampling.
errors_out (list or None): If set to a list, then TD-errors
computed from the given experiences are appended to the list.
Returns:
None
"""
has_weight = 'weight' in experiences[0][0]
exp_batch = batch_experiences(experiences,
xp=self.xp,
phi=self.phi,
gamma=self.gamma,
batch_states=self.batch_states)
if has_weight:
exp_batch['weights'] = self.xp.asarray(
[elem[0]['weight'] for elem in experiences],
dtype=self.xp.float32)
if errors_out is None:
errors_out = []
loss = self._compute_loss(exp_batch, errors_out=errors_out)
if has_weight:
self.replay_buffer.update_errors(errors_out)
# Update stats
self.average_loss *= self.average_loss_decay
self.average_loss += (1 - self.average_loss_decay) * float(loss.array)
self.model.cleargrads()
loss.backward()
self.optimizer.update()
def update(self, experiences, errors_out=None):
"""Update the model from experiences
This function is thread-safe.
Args:
experiences (list): list of lists of dicts.
The dict contains
state: cupy.ndarray or numpy.ndarray
action: int [0, n_action_types)
reward: float32
is_state_terminal: bool
next_state: cupy.ndarray or numpy.ndarray
weight (optional): float32
Returns:
None
"""
has_weight = 'weight' in experiences[0][0]
exp_batch = batch_experiences(experiences,
xp=self.xp,
phi=self.phi,
gamma=self.gamma,
batch_states=self.batch_states)
if has_weight:
exp_batch['weights'] = self.xp.asarray(
[elem[0]['weight'] for elem in experiences],
dtype=self.xp.float32)
if errors_out is None:
errors_out = []
loss = self._compute_loss(exp_batch, errors_out=errors_out)
if has_weight:
self.replay_buffer.update_errors(errors_out)
# Update stats
self.average_loss *= self.average_loss_decay
self.average_loss += (1 - self.average_loss_decay) * float(loss.array)
self.model.cleargrads()
loss.backward()
self.optimizer.update()
def update(self, experiences, errors_out=None):
"""Update the model from experiences
This function is thread-safe.
Args:
experiences (list): list of dict that contains
state: cupy.ndarray or numpy.ndarray
action: int [0, n_action_types)
reward: float32
next_state: cupy.ndarray or numpy.ndarray
next_legal_actions: list of booleans; True means legal
gamma (float): discount factor
Returns:
None
"""
has_weight = 'weight' in experiences[0]
exp_batch = batch_experiences(experiences,
xp=self.xp,
phi=self.phi,
batch_states=self.batch_states)
if has_weight:
exp_batch['weights'] = self.xp.asarray(
[elem['weight'] for elem in experiences],
dtype=self.xp.float32)
if errors_out is None:
errors_out = []
loss = self._compute_loss(exp_batch, self.gamma, errors_out=errors_out)
if has_weight:
self.replay_buffer.update_errors(errors_out)
# Update stats
self.average_loss *= self.average_loss_decay
self.average_loss += (1 - self.average_loss_decay) * float(loss.data)
self.model.cleargrads()
loss.backward()
self.optimizer.update()
def update_from_episodes(self, episodes, errors_out=None):
with state_reset(self.model):
with state_reset(self.target_model):
loss = 0
sorted_episodes = list(reversed(sorted(episodes, key=len)))
max_epi_len = len(sorted_episodes[0])
for i in range(max_epi_len):
transitions = []
for ep in sorted_episodes:
if len(ep) <= i:
break
transitions.append(ep[i])
batch = batch_experiences(transitions,
xp=self.xp,
phi=self.phi,
batch_states=self.batch_states)
if i == 0:
self.input_initial_batch_to_target_model(batch)
loss += self._compute_loss(batch, self.gamma)
loss /= max_epi_len
self.optimizer.zero_grads()
loss.backward()
self.optimizer.update()
def update(self, experiences, errors_out=None):
"""Update the model from experiences"""
batch = batch_experiences(experiences, self.xp, self.phi)
self.critic_optimizer.update(lambda: self.compute_critic_loss(batch))
self.actor_optimizer.update(lambda: self.compute_actor_loss(batch))
def update(self, experiences, errors_out=None):
"""Update the model from experiences."""
batch_size = len(experiences)
batch_exp = batch_experiences(
experiences,
xp=self.xp,
phi=self.phi,
gamma=self.gamma,
batch_states=self.batch_states,
)
batch_state = batch_exp['state']
batch_actions = batch_exp['action']
batch_next_state = batch_exp['next_state']
batch_rewards = batch_exp['reward']
batch_terminal = batch_exp['is_state_terminal']
batch_discount = batch_exp['discount']
# Update Q-function
def compute_critic_loss():
with chainer.no_backprop_mode():
pout = self.target_policy(batch_next_state)
next_actions = pout.sample()
next_q = self.target_q_function(batch_next_state, next_actions)
assert next_q.shape == (batch_size, 1)
target_q = (batch_rewards[..., None] +
(batch_discount[..., None] *
(1.0 - batch_terminal[..., None]) * next_q))
assert target_q.shape == (batch_size, 1)
predict_q = self.q_function(batch_state, batch_actions)
assert predict_q.shape == (batch_size, 1)
loss = F.mean_squared_error(target_q, predict_q)
# Update stats
self.average_critic_loss *= self.average_loss_decay
self.average_critic_loss += ((1 - self.average_loss_decay) *
float(loss.array))
return loss
def compute_actor_loss():
pout = self.policy(batch_state)
sampled_actions = pout.sample().array
log_probs = pout.log_prob(sampled_actions)
with chainer.using_config('train', False):
q = self.q_function(batch_state, sampled_actions)
v = self.q_function(batch_state, pout.most_probable)
advantage = F.reshape(q - v, (batch_size, ))
advantage = chainer.Variable(advantage.array)
loss = - F.sum(advantage * log_probs + self.beta * pout.entropy) \
/ batch_size
# Update stats
self.average_actor_loss *= self.average_loss_decay
self.average_actor_loss += ((1 - self.average_loss_decay) *
float(loss.array))
return loss
self.critic_optimizer.update(compute_critic_loss)
self.actor_optimizer.update(compute_actor_loss)
def update_from_replay(self):
if self.replay_buffer is None:
return
if len(self.replay_buffer) < self.replay_start_size:
return
if self.replay_buffer.n_episodes < self.batchsize:
return
if self.process_idx == 0:
self.logger.debug('update_from_replay')
episodes = self.replay_buffer.sample_episodes(self.batchsize,
max_len=self.t_max)
if isinstance(episodes, tuple):
# Prioritized replay
episodes, weights = episodes
else:
weights = [1] * len(episodes)
sorted_episodes = list(reversed(sorted(episodes, key=len)))
max_epi_len = len(sorted_episodes[0])
with state_reset(self.model):
# Batch computation of multiple episodes
rewards = {}
values = {}
next_values = {}
log_probs = {}
next_action_distrib = None
next_v = None
for t in range(max_epi_len):
transitions = []
for ep in sorted_episodes:
if len(ep) <= t:
break
transitions.append([ep[t]])
batch = batch_experiences(transitions,
xp=self.xp,
phi=self.phi,
gamma=self.gamma,
batch_states=self.batch_states)
batchsize = batch['action'].shape[0]
if next_action_distrib is not None:
action_distrib = next_action_distrib[0:batchsize]
v = next_v[0:batchsize]
else:
action_distrib, v = self.model(batch['state'])
next_action_distrib, next_v = self.model(batch['next_state'])
values[t] = v
next_values[t] = next_v * \
(1 - batch['is_state_terminal'].reshape(next_v.shape))
rewards[t] = chainer.cuda.to_cpu(batch['reward'])
log_probs[t] = action_distrib.log_prob(batch['action'])
# Loss is computed one by one episode
losses = []
for i, ep in enumerate(sorted_episodes):
e_values = {}
e_next_values = {}
e_rewards = {}
e_log_probs = {}
for t in range(len(ep)):
assert values[t].shape[0] > i
assert next_values[t].shape[0] > i
assert rewards[t].shape[0] > i
assert log_probs[t].shape[0] > i
e_values[t] = values[t][i:i + 1]
e_next_values[t] = next_values[t][i:i + 1]
e_rewards[t] = float(rewards[t][i:i + 1])
e_log_probs[t] = log_probs[t][i:i + 1]
losses.append(
self.compute_loss(t_start=0,
t_stop=len(ep),
rewards=e_rewards,
values=e_values,
next_values=e_next_values,
log_probs=e_log_probs))
loss = chainerrl.functions.weighted_sum_arrays(
losses, weights) / self.batchsize
self.update(loss)