def update(self) -> Dict[str, np.ndarray]:
"""
Updates model using buffer.
:param max_batches: The maximum number of batches to use per update.
:return: The loss of the update.
"""
# Don't continue training if the learning rate has reached 0, to reduce training time.
decay_lr = self.decay_learning_rate.get_value(self.policy.get_current_step())
if self.current_lr <= 1e-10: # Unlike in TF, this never actually reaches 0.
return {"Losses/Pretraining Loss": 0}
batch_losses = []
possible_demo_batches = (
self.demonstration_buffer.num_experiences // self.n_sequences
)
possible_batches = possible_demo_batches
max_batches = self.samples_per_update // self.n_sequences
n_epoch = self.num_epoch
for _ in range(n_epoch):
self.demonstration_buffer.shuffle(
sequence_length=self.policy.sequence_length
)
if max_batches == 0:
num_batches = possible_batches
else:
num_batches = min(possible_batches, max_batches)
for i in range(num_batches // self.policy.sequence_length):
demo_update_buffer = self.demonstration_buffer
start = i * self.n_sequences * self.policy.sequence_length
end = (i + 1) * self.n_sequences * self.policy.sequence_length
mini_batch_demo = demo_update_buffer.make_mini_batch(start, end)
run_out = self._update_batch(mini_batch_demo, self.n_sequences)
loss = run_out["loss"]
batch_losses.append(loss)
ModelUtils.update_learning_rate(self.optimizer, decay_lr)
self.current_lr = decay_lr
self.has_updated = True
update_stats = {"Losses/Pretraining Loss": np.mean(batch_losses)}
return update_stats
def update(self, batch: AgentBuffer,
num_sequences: int) -> Dict[str, float]:
"""
Performs update on model.
:param batch: Batch of experiences.
:param num_sequences: Number of sequences to process.
:return: Results of update.
"""
# Get decayed parameters
decay_lr = self.decay_learning_rate.get_value(
self.policy.get_current_step())
decay_eps = self.decay_epsilon.get_value(
self.policy.get_current_step())
decay_bet = self.decay_beta.get_value(self.policy.get_current_step())
returns = {}
old_values = {}
for name in self.reward_signals:
old_values[name] = ModelUtils.list_to_tensor(
batch[f"{name}_value_estimates"])
returns[name] = ModelUtils.list_to_tensor(batch[f"{name}_returns"])
vec_obs = [ModelUtils.list_to_tensor(batch["vector_obs"])]
act_masks = ModelUtils.list_to_tensor(batch["action_mask"])
if self.policy.use_continuous_act:
actions = ModelUtils.list_to_tensor(batch["actions"]).unsqueeze(-1)
else:
actions = ModelUtils.list_to_tensor(batch["actions"],
dtype=torch.long)
memories = [
ModelUtils.list_to_tensor(batch["memory"][i]) for i in range(
0, len(batch["memory"]), self.policy.sequence_length)
]
if len(memories) > 0:
memories = torch.stack(memories).unsqueeze(0)
if self.policy.use_vis_obs:
vis_obs = []
for idx, _ in enumerate(
self.policy.actor_critic.network_body.visual_encoders):
vis_ob = ModelUtils.list_to_tensor(batch["visual_obs%d" % idx])
vis_obs.append(vis_ob)
else:
vis_obs = []
log_probs, entropy, values = self.policy.evaluate_actions(
vec_obs,
vis_obs,
masks=act_masks,
actions=actions,
memories=memories,
seq_len=self.policy.sequence_length,
)
loss_masks = ModelUtils.list_to_tensor(batch["masks"],
dtype=torch.bool)
value_loss = self.ppo_value_loss(values, old_values, returns,
decay_eps, loss_masks)
policy_loss = self.ppo_policy_loss(
ModelUtils.list_to_tensor(batch["advantages"]),
log_probs,
ModelUtils.list_to_tensor(batch["action_probs"]),
loss_masks,
)
loss = (policy_loss + 0.5 * value_loss -
decay_bet * ModelUtils.masked_mean(entropy, loss_masks))
# Set optimizer learning rate
ModelUtils.update_learning_rate(self.optimizer, decay_lr)
self.optimizer.zero_grad()
loss.backward()
self.optimizer.step()
update_stats = {
"Losses/Policy Loss": abs(policy_loss.detach().cpu().numpy()),
"Losses/Value Loss": value_loss.detach().cpu().numpy(),
"Policy/Learning Rate": decay_lr,
"Policy/Epsilon": decay_eps,
"Policy/Beta": decay_bet,
}
for reward_provider in self.reward_signals.values():
update_stats.update(reward_provider.update(batch))
return update_stats
def update(self, batch: AgentBuffer,
num_sequences: int) -> Dict[str, float]:
"""
Performs update on model.
:param batch: Batch of experiences.
:param num_sequences: Number of sequences to process.
:return: Results of update.
"""
# Get decayed parameters
decay_lr = self.decay_learning_rate.get_value(
self.policy.get_current_step())
decay_eps = self.decay_epsilon.get_value(
self.policy.get_current_step())
decay_bet = self.decay_beta.get_value(self.policy.get_current_step())
returns = {}
old_values = {}
for name in self.reward_signals:
old_values[name] = ModelUtils.list_to_tensor(
batch[RewardSignalUtil.value_estimates_key(name)])
returns[name] = ModelUtils.list_to_tensor(
batch[RewardSignalUtil.returns_key(name)])
n_obs = len(self.policy.behavior_spec.observation_specs)
current_obs = ObsUtil.from_buffer(batch, n_obs)
# Convert to tensors
current_obs = [ModelUtils.list_to_tensor(obs) for obs in current_obs]
act_masks = ModelUtils.list_to_tensor(batch[BufferKey.ACTION_MASK])
actions = AgentAction.from_buffer(batch)
memories = [
ModelUtils.list_to_tensor(batch[BufferKey.MEMORY][i]) for i in
range(0, len(batch[BufferKey.MEMORY]), self.policy.sequence_length)
]
if len(memories) > 0:
memories = torch.stack(memories).unsqueeze(0)
# Get value memories
value_memories = [
ModelUtils.list_to_tensor(batch[BufferKey.CRITIC_MEMORY][i])
for i in range(0, len(batch[BufferKey.CRITIC_MEMORY]),
self.policy.sequence_length)
]
if len(value_memories) > 0:
value_memories = torch.stack(value_memories).unsqueeze(0)
log_probs, entropy = self.policy.evaluate_actions(
current_obs,
masks=act_masks,
actions=actions,
memories=memories,
seq_len=self.policy.sequence_length,
)
values, _ = self.critic.critic_pass(
current_obs,
memories=value_memories,
sequence_length=self.policy.sequence_length,
)
old_log_probs = ActionLogProbs.from_buffer(batch).flatten()
log_probs = log_probs.flatten()
loss_masks = ModelUtils.list_to_tensor(batch[BufferKey.MASKS],
dtype=torch.bool)
value_loss = self.ppo_value_loss(values, old_values, returns,
decay_eps, loss_masks)
policy_loss = self.ppo_policy_loss(
ModelUtils.list_to_tensor(batch[BufferKey.ADVANTAGES]),
log_probs,
old_log_probs,
loss_masks,
)
loss = (policy_loss + 0.5 * value_loss -
decay_bet * ModelUtils.masked_mean(entropy, loss_masks))
# Set optimizer learning rate
ModelUtils.update_learning_rate(self.optimizer, decay_lr)
self.optimizer.zero_grad()
loss.backward()
self.optimizer.step()
update_stats = {
# NOTE: abs() is not technically correct, but matches the behavior in TensorFlow.
# TODO: After PyTorch is default, change to something more correct.
"Losses/Policy Loss": torch.abs(policy_loss).item(),
"Losses/Value Loss": value_loss.item(),
"Policy/Learning Rate": decay_lr,
"Policy/Epsilon": decay_eps,
"Policy/Beta": decay_bet,
}
for reward_provider in self.reward_signals.values():
update_stats.update(reward_provider.update(batch))
return update_stats
def update(self, batch: AgentBuffer,
num_sequences: int) -> Dict[str, float]:
"""
Updates model using buffer.
:param num_sequences: Number of trajectories in batch.
:param batch: Experience mini-batch.
:param update_target: Whether or not to update target value network
:param reward_signal_batches: Minibatches to use for updating the reward signals,
indexed by name. If none, don't update the reward signals.
:return: Output from update process.
"""
rewards = {}
for name in self.reward_signals:
rewards[name] = ModelUtils.list_to_tensor(batch[f"{name}_rewards"])
n_obs = len(self.policy.behavior_spec.sensor_specs)
current_obs = ObsUtil.from_buffer(batch, n_obs)
# Convert to tensors
current_obs = [ModelUtils.list_to_tensor(obs) for obs in current_obs]
next_obs = ObsUtil.from_buffer_next(batch, n_obs)
# Convert to tensors
next_obs = [ModelUtils.list_to_tensor(obs) for obs in next_obs]
act_masks = ModelUtils.list_to_tensor(batch["action_mask"])
actions = AgentAction.from_dict(batch)
memories_list = [
ModelUtils.list_to_tensor(batch["memory"][i]) for i in range(
0, len(batch["memory"]), self.policy.sequence_length)
]
# LSTM shouldn't have sequence length <1, but stop it from going out of the index if true.
offset = 1 if self.policy.sequence_length > 1 else 0
next_memories_list = [
ModelUtils.list_to_tensor(
batch["memory"][i]
[self.policy.m_size //
2:]) # only pass value part of memory to target network
for i in range(offset, len(batch["memory"]),
self.policy.sequence_length)
]
if len(memories_list) > 0:
memories = torch.stack(memories_list).unsqueeze(0)
next_memories = torch.stack(next_memories_list).unsqueeze(0)
else:
memories = None
next_memories = None
# Q network memories are 0'ed out, since we don't have them during inference.
q_memories = (torch.zeros_like(next_memories)
if next_memories is not None else None)
# Copy normalizers from policy
self.value_network.q1_network.network_body.copy_normalization(
self.policy.actor_critic.network_body)
self.value_network.q2_network.network_body.copy_normalization(
self.policy.actor_critic.network_body)
self.target_network.network_body.copy_normalization(
self.policy.actor_critic.network_body)
(
sampled_actions,
log_probs,
_,
value_estimates,
_,
) = self.policy.actor_critic.get_action_stats_and_value(
current_obs,
masks=act_masks,
memories=memories,
sequence_length=self.policy.sequence_length,
)
cont_sampled_actions = sampled_actions.continuous_tensor
cont_actions = actions.continuous_tensor
q1p_out, q2p_out = self.value_network(
current_obs,
cont_sampled_actions,
memories=q_memories,
sequence_length=self.policy.sequence_length,
q2_grad=False,
)
q1_out, q2_out = self.value_network(
current_obs,
cont_actions,
memories=q_memories,
sequence_length=self.policy.sequence_length,
)
if self._action_spec.discrete_size > 0:
disc_actions = actions.discrete_tensor
q1_stream = self._condense_q_streams(q1_out, disc_actions)
q2_stream = self._condense_q_streams(q2_out, disc_actions)
else:
q1_stream, q2_stream = q1_out, q2_out
with torch.no_grad():
target_values, _ = self.target_network(
next_obs,
memories=next_memories,
sequence_length=self.policy.sequence_length,
)
masks = ModelUtils.list_to_tensor(batch["masks"], dtype=torch.bool)
dones = ModelUtils.list_to_tensor(batch["done"])
q1_loss, q2_loss = self.sac_q_loss(q1_stream, q2_stream, target_values,
dones, rewards, masks)
value_loss = self.sac_value_loss(log_probs, value_estimates, q1p_out,
q2p_out, masks)
policy_loss = self.sac_policy_loss(log_probs, q1p_out, masks)
entropy_loss = self.sac_entropy_loss(log_probs, masks)
total_value_loss = q1_loss + q2_loss + value_loss
decay_lr = self.decay_learning_rate.get_value(
self.policy.get_current_step())
ModelUtils.update_learning_rate(self.policy_optimizer, decay_lr)
self.policy_optimizer.zero_grad()
policy_loss.backward()
self.policy_optimizer.step()
ModelUtils.update_learning_rate(self.value_optimizer, decay_lr)
self.value_optimizer.zero_grad()
total_value_loss.backward()
self.value_optimizer.step()
ModelUtils.update_learning_rate(self.entropy_optimizer, decay_lr)
self.entropy_optimizer.zero_grad()
entropy_loss.backward()
self.entropy_optimizer.step()
# Update target network
ModelUtils.soft_update(self.policy.actor_critic.critic,
self.target_network, self.tau)
update_stats = {
"Losses/Policy Loss":
policy_loss.item(),
"Losses/Value Loss":
value_loss.item(),
"Losses/Q1 Loss":
q1_loss.item(),
"Losses/Q2 Loss":
q2_loss.item(),
"Policy/Discrete Entropy Coeff":
torch.mean(torch.exp(self._log_ent_coef.discrete)).item(),
"Policy/Continuous Entropy Coeff":
torch.mean(torch.exp(self._log_ent_coef.continuous)).item(),
"Policy/Learning Rate":
decay_lr,
}
return update_stats
def update(self, batch: AgentBuffer,
num_sequences: int) -> Dict[str, float]:
"""
Updates model using buffer.
:param num_sequences: Number of trajectories in batch.
:param batch: Experience mini-batch.
:param update_target: Whether or not to update target value network
:param reward_signal_batches: Minibatches to use for updating the reward signals,
indexed by name. If none, don't update the reward signals.
:return: Output from update process.
"""
rewards = {}
for name in self.reward_signals:
rewards[name] = ModelUtils.list_to_tensor(
batch[RewardSignalUtil.rewards_key(name)])
n_obs = len(self.policy.behavior_spec.observation_specs)
current_obs = ObsUtil.from_buffer(batch, n_obs)
# Convert to tensors
current_obs = [ModelUtils.list_to_tensor(obs) for obs in current_obs]
next_obs = ObsUtil.from_buffer_next(batch, n_obs)
# Convert to tensors
next_obs = [ModelUtils.list_to_tensor(obs) for obs in next_obs]
act_masks = ModelUtils.list_to_tensor(batch[BufferKey.ACTION_MASK])
actions = AgentAction.from_buffer(batch)
memories_list = [
ModelUtils.list_to_tensor(batch[BufferKey.MEMORY][i]) for i in
range(0, len(batch[BufferKey.MEMORY]), self.policy.sequence_length)
]
# LSTM shouldn't have sequence length <1, but stop it from going out of the index if true.
value_memories_list = [
ModelUtils.list_to_tensor(batch[BufferKey.CRITIC_MEMORY][i])
for i in range(0, len(batch[BufferKey.CRITIC_MEMORY]),
self.policy.sequence_length)
]
if len(memories_list) > 0:
memories = torch.stack(memories_list).unsqueeze(0)
value_memories = torch.stack(value_memories_list).unsqueeze(0)
else:
memories = None
value_memories = None
# Q and V network memories are 0'ed out, since we don't have them during inference.
q_memories = (torch.zeros_like(value_memories)
if value_memories is not None else None)
# Copy normalizers from policy
self.q_network.q1_network.network_body.copy_normalization(
self.policy.actor.network_body)
self.q_network.q2_network.network_body.copy_normalization(
self.policy.actor.network_body)
self.target_network.network_body.copy_normalization(
self.policy.actor.network_body)
self._critic.network_body.copy_normalization(
self.policy.actor.network_body)
sampled_actions, log_probs, _, _, = self.policy.actor.get_action_and_stats(
current_obs,
masks=act_masks,
memories=memories,
sequence_length=self.policy.sequence_length,
)
value_estimates, _ = self._critic.critic_pass(
current_obs,
value_memories,
sequence_length=self.policy.sequence_length)
cont_sampled_actions = sampled_actions.continuous_tensor
cont_actions = actions.continuous_tensor
q1p_out, q2p_out = self.q_network(
current_obs,
cont_sampled_actions,
memories=q_memories,
sequence_length=self.policy.sequence_length,
q2_grad=False,
)
q1_out, q2_out = self.q_network(
current_obs,
cont_actions,
memories=q_memories,
sequence_length=self.policy.sequence_length,
)
if self._action_spec.discrete_size > 0:
disc_actions = actions.discrete_tensor
q1_stream = self._condense_q_streams(q1_out, disc_actions)
q2_stream = self._condense_q_streams(q2_out, disc_actions)
else:
q1_stream, q2_stream = q1_out, q2_out
with torch.no_grad():
# Since we didn't record the next value memories, evaluate one step in the critic to
# get them.
if value_memories is not None:
# Get the first observation in each sequence
just_first_obs = [
_obs[::self.policy.sequence_length] for _obs in current_obs
]
_, next_value_memories = self._critic.critic_pass(
just_first_obs, value_memories, sequence_length=1)
else:
next_value_memories = None
target_values, _ = self.target_network(
next_obs,
memories=next_value_memories,
sequence_length=self.policy.sequence_length,
)
masks = ModelUtils.list_to_tensor(batch[BufferKey.MASKS],
dtype=torch.bool)
dones = ModelUtils.list_to_tensor(batch[BufferKey.DONE])
q1_loss, q2_loss = self.sac_q_loss(q1_stream, q2_stream, target_values,
dones, rewards, masks)
value_loss = self.sac_value_loss(log_probs, value_estimates, q1p_out,
q2p_out, masks)
policy_loss = self.sac_policy_loss(log_probs, q1p_out, masks)
entropy_loss = self.sac_entropy_loss(log_probs, masks)
total_value_loss = q1_loss + q2_loss
if self.policy.shared_critic:
policy_loss += value_loss
else:
total_value_loss += value_loss
decay_lr = self.decay_learning_rate.get_value(
self.policy.get_current_step())
ModelUtils.update_learning_rate(self.policy_optimizer, decay_lr)
self.policy_optimizer.zero_grad()
policy_loss.backward()
self.policy_optimizer.step()
ModelUtils.update_learning_rate(self.value_optimizer, decay_lr)
self.value_optimizer.zero_grad()
total_value_loss.backward()
self.value_optimizer.step()
ModelUtils.update_learning_rate(self.entropy_optimizer, decay_lr)
self.entropy_optimizer.zero_grad()
entropy_loss.backward()
self.entropy_optimizer.step()
# Update target network
ModelUtils.soft_update(self._critic, self.target_network, self.tau)
update_stats = {
"Losses/Policy Loss":
policy_loss.item(),
"Losses/Value Loss":
value_loss.item(),
"Losses/Q1 Loss":
q1_loss.item(),
"Losses/Q2 Loss":
q2_loss.item(),
"Policy/Discrete Entropy Coeff":
torch.mean(torch.exp(self._log_ent_coef.discrete)).item(),
"Policy/Continuous Entropy Coeff":
torch.mean(torch.exp(self._log_ent_coef.continuous)).item(),
"Policy/Learning Rate":
decay_lr,
}
return update_stats
def update(self, batch: AgentBuffer, num_sequences: int) -> Dict[str, float]:
"""
Updates model using buffer.
:param num_sequences: Number of trajectories in batch.
:param batch: Experience mini-batch.
:param update_target: Whether or not to update target value network
:param reward_signal_batches: Minibatches to use for updating the reward signals,
indexed by name. If none, don't update the reward signals.
:return: Output from update process.
"""
rewards = {}
for name in self.reward_signals:
rewards[name] = ModelUtils.list_to_tensor(batch[f"{name}_rewards"])
vec_obs = [ModelUtils.list_to_tensor(batch["vector_obs"])]
next_vec_obs = [ModelUtils.list_to_tensor(batch["next_vector_in"])]
act_masks = ModelUtils.list_to_tensor(batch["action_mask"])
if self.policy.use_continuous_act:
actions = ModelUtils.list_to_tensor(batch["actions"]).unsqueeze(-1)
else:
actions = ModelUtils.list_to_tensor(batch["actions"], dtype=torch.long)
memories_list = [
ModelUtils.list_to_tensor(batch["memory"][i])
for i in range(0, len(batch["memory"]), self.policy.sequence_length)
]
# LSTM shouldn't have sequence length <1, but stop it from going out of the index if true.
offset = 1 if self.policy.sequence_length > 1 else 0
next_memories_list = [
ModelUtils.list_to_tensor(
batch["memory"][i][self.policy.m_size // 2 :]
) # only pass value part of memory to target network
for i in range(offset, len(batch["memory"]), self.policy.sequence_length)
]
if len(memories_list) > 0:
memories = torch.stack(memories_list).unsqueeze(0)
next_memories = torch.stack(next_memories_list).unsqueeze(0)
else:
memories = None
next_memories = None
# Q network memories are 0'ed out, since we don't have them during inference.
q_memories = (
torch.zeros_like(next_memories) if next_memories is not None else None
)
vis_obs: List[torch.Tensor] = []
next_vis_obs: List[torch.Tensor] = []
if self.policy.use_vis_obs:
vis_obs = []
for idx, _ in enumerate(
self.policy.actor_critic.network_body.visual_processors
):
vis_ob = ModelUtils.list_to_tensor(batch["visual_obs%d" % idx])
vis_obs.append(vis_ob)
next_vis_ob = ModelUtils.list_to_tensor(
batch["next_visual_obs%d" % idx]
)
next_vis_obs.append(next_vis_ob)
# Copy normalizers from policy
self.value_network.q1_network.network_body.copy_normalization(
self.policy.actor_critic.network_body
)
self.value_network.q2_network.network_body.copy_normalization(
self.policy.actor_critic.network_body
)
self.target_network.network_body.copy_normalization(
self.policy.actor_critic.network_body
)
(sampled_actions, _, log_probs, _, _) = self.policy.sample_actions(
vec_obs,
vis_obs,
masks=act_masks,
memories=memories,
seq_len=self.policy.sequence_length,
all_log_probs=not self.policy.use_continuous_act,
)
value_estimates, _ = self.policy.actor_critic.critic_pass(
vec_obs, vis_obs, memories, sequence_length=self.policy.sequence_length
)
if self.policy.use_continuous_act:
squeezed_actions = actions.squeeze(-1)
# Only need grad for q1, as that is used for policy.
q1p_out, q2p_out = self.value_network(
vec_obs,
vis_obs,
sampled_actions,
memories=q_memories,
sequence_length=self.policy.sequence_length,
q2_grad=False,
)
q1_out, q2_out = self.value_network(
vec_obs,
vis_obs,
squeezed_actions,
memories=q_memories,
sequence_length=self.policy.sequence_length,
)
q1_stream, q2_stream = q1_out, q2_out
else:
# For discrete, you don't need to backprop through the Q for the policy
q1p_out, q2p_out = self.value_network(
vec_obs,
vis_obs,
memories=q_memories,
sequence_length=self.policy.sequence_length,
q1_grad=False,
q2_grad=False,
)
q1_out, q2_out = self.value_network(
vec_obs,
vis_obs,
memories=q_memories,
sequence_length=self.policy.sequence_length,
)
q1_stream = self._condense_q_streams(q1_out, actions)
q2_stream = self._condense_q_streams(q2_out, actions)
with torch.no_grad():
target_values, _ = self.target_network(
next_vec_obs,
next_vis_obs,
memories=next_memories,
sequence_length=self.policy.sequence_length,
)
masks = ModelUtils.list_to_tensor(batch["masks"], dtype=torch.bool)
use_discrete = not self.policy.use_continuous_act
dones = ModelUtils.list_to_tensor(batch["done"])
q1_loss, q2_loss = self.sac_q_loss(
q1_stream, q2_stream, target_values, dones, rewards, masks
)
value_loss = self.sac_value_loss(
log_probs, value_estimates, q1p_out, q2p_out, masks, use_discrete
)
policy_loss = self.sac_policy_loss(log_probs, q1p_out, masks, use_discrete)
entropy_loss = self.sac_entropy_loss(log_probs, masks, use_discrete)
total_value_loss = q1_loss + q2_loss + value_loss
decay_lr = self.decay_learning_rate.get_value(self.policy.get_current_step())
ModelUtils.update_learning_rate(self.policy_optimizer, decay_lr)
self.policy_optimizer.zero_grad()
policy_loss.backward()
self.policy_optimizer.step()
ModelUtils.update_learning_rate(self.value_optimizer, decay_lr)
self.value_optimizer.zero_grad()
total_value_loss.backward()
self.value_optimizer.step()
ModelUtils.update_learning_rate(self.entropy_optimizer, decay_lr)
self.entropy_optimizer.zero_grad()
entropy_loss.backward()
self.entropy_optimizer.step()
# Update target network
ModelUtils.soft_update(
self.policy.actor_critic.critic, self.target_network, self.tau
)
update_stats = {
"Losses/Policy Loss": policy_loss.item(),
"Losses/Value Loss": value_loss.item(),
"Losses/Q1 Loss": q1_loss.item(),
"Losses/Q2 Loss": q2_loss.item(),
"Policy/Entropy Coeff": torch.mean(torch.exp(self._log_ent_coef)).item(),
"Policy/Learning Rate": decay_lr,
}
return update_stats
