Porting to sb3=2.1.0

This commit is contained in:
2023-11-11 12:14:30 +01:00
parent 3e27ad3766
commit 1c1a909d27
15 changed files with 78 additions and 44 deletions
+14
View File
@@ -0,0 +1,14 @@
from sbBrix.ppo import PPO
from sbBrix.sac import SAC
try:
import priorConditionedAnnealing as pca
except ModuleNotFoundError:
class pca():
def PCA_Distribution(*args, **kwargs):
raise Exception('PCA is not installed; cannot initialize PCA_Distribution.')
__all__ = [
"PPO",
"SAC",
]
@@ -0,0 +1,45 @@
from stable_baselines3.common.distributions import *
from metastable_baselines2.pca import PCA_Distribution
def _patched_make_proba_distribution(
action_space: spaces.Space, use_sde: bool = False, use_pca: bool = False, dist_kwargs: Optional[Dict[str, Any]] = None
) -> Distribution:
"""
Return an instance of Distribution for the correct type of action space
:param action_space: the input action space
:param use_sde: Force the use of StateDependentNoiseDistribution
instead of DiagGaussianDistribution
:param dist_kwargs: Keyword arguments to pass to the probability distribution
:return: the appropriate Distribution object
"""
assert not (use_sde and use_pca), 'Can not mix sde and pca!'
if dist_kwargs is None:
dist_kwargs = {}
if isinstance(action_space, spaces.Box):
if use_sde:
cls = StateDependentNoiseDistribution
elif use_pca:
cls = PCA_Distribution
else:
cls = DiagGaussianDistribution
return cls(get_action_dim(action_space), **dist_kwargs)
elif isinstance(action_space, spaces.Discrete):
return CategoricalDistribution(action_space.n, **dist_kwargs)
elif isinstance(action_space, spaces.MultiDiscrete):
return MultiCategoricalDistribution(list(action_space.nvec), **dist_kwargs)
elif isinstance(action_space, spaces.MultiBinary):
return BernoulliDistribution(action_space.n, **dist_kwargs)
else:
raise NotImplementedError(
"Error: probability distribution, not implemented for action space"
f"of type {type(action_space)}."
" Must be of type Gym Spaces: Box, Discrete, MultiDiscrete or MultiBinary."
)
_orig_make_propa_distribution, make_proba_distribution = make_proba_distribution, _patched_make_proba_distribution
@@ -0,0 +1,555 @@
from stable_baselines3.common.off_policy_algorithm import *
class BetterOffPolicyAlgorithm(OffPolicyAlgorithm):
"""
The base for Off-Policy algorithms (ex: SAC/TD3)
:param policy: The policy model to use (MlpPolicy, CnnPolicy, ...)
:param env: The environment to learn from
(if registered in Gym, can be str. Can be None for loading trained models)
:param learning_rate: learning rate for the optimizer,
it can be a function of the current progress remaining (from 1 to 0)
:param buffer_size: size of the replay buffer
:param learning_starts: how many steps of the model to collect transitions for before learning starts
:param batch_size: Minibatch size for each gradient update
:param tau: the soft update coefficient ("Polyak update", between 0 and 1)
:param gamma: the discount factor
:param train_freq: Update the model every ``train_freq`` steps. Alternatively pass a tuple of frequency and unit
like ``(5, "step")`` or ``(2, "episode")``.
:param gradient_steps: How many gradient steps to do after each rollout (see ``train_freq``)
Set to ``-1`` means to do as many gradient steps as steps done in the environment
during the rollout.
:param action_noise: the action noise type (None by default), this can help
for hard exploration problem. Cf common.noise for the different action noise type.
:param replay_buffer_class: Replay buffer class to use (for instance ``HerReplayBuffer``).
If ``None``, it will be automatically selected.
:param replay_buffer_kwargs: Keyword arguments to pass to the replay buffer on creation.
:param optimize_memory_usage: Enable a memory efficient variant of the replay buffer
at a cost of more complexity.
See https://github.com/DLR-RM/stable-baselines3/issues/37#issuecomment-637501195
:param policy_kwargs: Additional arguments to be passed to the policy on creation
:param stats_window_size: Window size for the rollout logging, specifying the number of episodes to average
the reported success rate, mean episode length, and mean reward over
:param tensorboard_log: the log location for tensorboard (if None, no logging)
:param verbose: Verbosity level: 0 for no output, 1 for info messages (such as device or wrappers used), 2 for
debug messages
:param device: Device on which the code should run.
By default, it will try to use a Cuda compatible device and fallback to cpu
if it is not possible.
:param support_multi_env: Whether the algorithm supports training
with multiple environments (as in A2C)
:param monitor_wrapper: When creating an environment, whether to wrap it
or not in a Monitor wrapper.
:param seed: Seed for the pseudo random generators
:param use_sde: Whether to use State Dependent Exploration (SDE)
instead of action noise exploration (default: False)
:param sde_sample_freq: Sample a new noise matrix every n steps when using gSDE
Default: -1 (only sample at the beginning of the rollout)
:param use_sde_at_warmup: Whether to use gSDE instead of uniform sampling
during the warm up phase (before learning starts)
:param sde_support: Whether the model support gSDE or not
:param supported_action_spaces: The action spaces supported by the algorithm.
"""
def __init__(
self,
policy: Union[str, Type[BasePolicy]],
env: Union[GymEnv, str],
learning_rate: Union[float, Schedule],
buffer_size: int = 1_000_000, # 1e6
learning_starts: int = 100,
batch_size: int = 256,
tau: float = 0.005,
gamma: float = 0.99,
train_freq: Union[int, Tuple[int, str]] = (1, "step"),
gradient_steps: int = 1,
action_noise: Optional[ActionNoise] = None,
replay_buffer_class: Optional[Type[ReplayBuffer]] = None,
replay_buffer_kwargs: Optional[Dict[str, Any]] = None,
optimize_memory_usage: bool = False,
policy_kwargs: Optional[Dict[str, Any]] = None,
stats_window_size: int = 100,
tensorboard_log: Optional[str] = None,
verbose: int = 0,
device: Union[th.device, str] = "auto",
support_multi_env: bool = False,
monitor_wrapper: bool = True,
seed: Optional[int] = None,
use_sde: bool = False,
sde_sample_freq: int = -1,
use_sde_at_warmup: bool = False,
sde_support: bool = True,
use_pca: bool = False,
supported_action_spaces: Optional[Tuple[spaces.Space, ...]] = None,
):
assert not (use_sde and use_pca)
self.use_pca = use_pca
policy_kwargs["use_pca"] = self.use_pca
super().__init__(
policy=policy,
env=env,
learning_rate=learning_rate,
policy_kwargs=policy_kwargs,
stats_window_size=stats_window_size,
tensorboard_log=tensorboard_log,
verbose=verbose,
device=device,
support_multi_env=support_multi_env,
monitor_wrapper=monitor_wrapper,
seed=seed,
use_sde=use_sde,
sde_sample_freq=sde_sample_freq,
supported_action_spaces=supported_action_spaces,
buffer_size=buffer_size,
batch_size=batch_size,
learning_starts=learning_starts,
tau=tau,
gamma=gamma,
gradient_steps=gradient_steps,
action_noise=action_noise,
optimize_memory_usage=optimize_memory_usage,
replay_buffer_class=replay_buffer_class,
replay_buffer_kwargs=replay_buffer_kwargs,
train_freq=train_freq,
use_sde_at_warmup=use_sde_at_warmup,
sde_support=sde_support,
)
def _convert_train_freq(self) -> None:
"""
Convert `train_freq` parameter (int or tuple)
to a TrainFreq object.
"""
if not isinstance(self.train_freq, TrainFreq):
train_freq = self.train_freq
# The value of the train frequency will be checked later
if not isinstance(train_freq, tuple):
train_freq = (train_freq, "step")
try:
train_freq = (train_freq[0], TrainFrequencyUnit(train_freq[1]))
except ValueError as e:
raise ValueError(
f"The unit of the `train_freq` must be either 'step' or 'episode' not '{train_freq[1]}'!"
) from e
if not isinstance(train_freq[0], int):
raise ValueError(f"The frequency of `train_freq` must be an integer and not {train_freq[0]}")
self.train_freq = TrainFreq(*train_freq)
def _setup_model(self) -> None:
self._setup_lr_schedule()
self.set_random_seed(self.seed)
if self.replay_buffer_class is None:
if isinstance(self.observation_space, spaces.Dict):
self.replay_buffer_class = DictReplayBuffer
else:
self.replay_buffer_class = ReplayBuffer
if self.replay_buffer is None:
# Make a local copy as we should not pickle
# the environment when using HerReplayBuffer
replay_buffer_kwargs = self.replay_buffer_kwargs.copy()
if issubclass(self.replay_buffer_class, HerReplayBuffer):
assert self.env is not None, "You must pass an environment when using `HerReplayBuffer`"
replay_buffer_kwargs["env"] = self.env
self.replay_buffer = self.replay_buffer_class(
self.buffer_size,
self.observation_space,
self.action_space,
device=self.device,
n_envs=self.n_envs,
optimize_memory_usage=self.optimize_memory_usage,
**replay_buffer_kwargs, # pytype:disable=wrong-keyword-args
)
self.policy = self.policy_class( # pytype:disable=not-instantiable
self.observation_space,
self.action_space,
self.lr_schedule,
**self.policy_kwargs, # pytype:disable=not-instantiable
)
self.policy = self.policy.to(self.device)
# Convert train freq parameter to TrainFreq object
self._convert_train_freq()
def save_replay_buffer(self, path: Union[str, pathlib.Path, io.BufferedIOBase]) -> None:
"""
Save the replay buffer as a pickle file.
:param path: Path to the file where the replay buffer should be saved.
if path is a str or pathlib.Path, the path is automatically created if necessary.
"""
assert self.replay_buffer is not None, "The replay buffer is not defined"
save_to_pkl(path, self.replay_buffer, self.verbose)
def load_replay_buffer(
self,
path: Union[str, pathlib.Path, io.BufferedIOBase],
truncate_last_traj: bool = True,
) -> None:
"""
Load a replay buffer from a pickle file.
:param path: Path to the pickled replay buffer.
:param truncate_last_traj: When using ``HerReplayBuffer`` with online sampling:
If set to ``True``, we assume that the last trajectory in the replay buffer was finished
(and truncate it).
If set to ``False``, we assume that we continue the same trajectory (same episode).
"""
self.replay_buffer = load_from_pkl(path, self.verbose)
assert isinstance(self.replay_buffer, ReplayBuffer), "The replay buffer must inherit from ReplayBuffer class"
# Backward compatibility with SB3 < 2.1.0 replay buffer
# Keep old behavior: do not handle timeout termination separately
if not hasattr(self.replay_buffer, "handle_timeout_termination"): # pragma: no cover
self.replay_buffer.handle_timeout_termination = False
self.replay_buffer.timeouts = np.zeros_like(self.replay_buffer.dones)
if isinstance(self.replay_buffer, HerReplayBuffer):
assert self.env is not None, "You must pass an environment at load time when using `HerReplayBuffer`"
self.replay_buffer.set_env(self.get_env())
if truncate_last_traj:
self.replay_buffer.truncate_last_trajectory()
def _setup_learn(
self,
total_timesteps: int,
callback: MaybeCallback = None,
reset_num_timesteps: bool = True,
tb_log_name: str = "run",
progress_bar: bool = False,
) -> Tuple[int, BaseCallback]:
"""
cf `BaseAlgorithm`.
"""
# Prevent continuity issue by truncating trajectory
# when using memory efficient replay buffer
# see https://github.com/DLR-RM/stable-baselines3/issues/46
replay_buffer = self.replay_buffer
truncate_last_traj = (
self.optimize_memory_usage
and reset_num_timesteps
and replay_buffer is not None
and (replay_buffer.full or replay_buffer.pos > 0)
)
if truncate_last_traj:
warnings.warn(
"The last trajectory in the replay buffer will be truncated, "
"see https://github.com/DLR-RM/stable-baselines3/issues/46."
"You should use `reset_num_timesteps=False` or `optimize_memory_usage=False`"
"to avoid that issue."
)
# Go to the previous index
pos = (replay_buffer.pos - 1) % replay_buffer.buffer_size
replay_buffer.dones[pos] = True
return super()._setup_learn(
total_timesteps,
callback,
reset_num_timesteps,
tb_log_name,
progress_bar,
)
def learn(
self: SelfOffPolicyAlgorithm,
total_timesteps: int,
callback: MaybeCallback = None,
log_interval: int = 4,
tb_log_name: str = "run",
reset_num_timesteps: bool = True,
progress_bar: bool = False,
) -> SelfOffPolicyAlgorithm:
total_timesteps, callback = self._setup_learn(
total_timesteps,
callback,
reset_num_timesteps,
tb_log_name,
progress_bar,
)
callback.on_training_start(locals(), globals())
while self.num_timesteps < total_timesteps:
rollout = self.collect_rollouts(
self.env,
train_freq=self.train_freq,
action_noise=self.action_noise,
callback=callback,
learning_starts=self.learning_starts,
replay_buffer=self.replay_buffer,
log_interval=log_interval,
)
if rollout.continue_training is False:
break
if self.num_timesteps > 0 and self.num_timesteps > self.learning_starts:
# If no `gradient_steps` is specified,
# do as many gradients steps as steps performed during the rollout
gradient_steps = self.gradient_steps if self.gradient_steps >= 0 else rollout.episode_timesteps
# Special case when the user passes `gradient_steps=0`
if gradient_steps > 0:
self.train(batch_size=self.batch_size, gradient_steps=gradient_steps)
callback.on_training_end()
return self
def train(self, gradient_steps: int, batch_size: int) -> None:
"""
Sample the replay buffer and do the updates
(gradient descent and update target networks)
"""
raise NotImplementedError()
def _sample_action(
self,
learning_starts: int,
action_noise: Optional[ActionNoise] = None,
n_envs: int = 1,
) -> Tuple[np.ndarray, np.ndarray]:
"""
Sample an action according to the exploration policy.
This is either done by sampling the probability distribution of the policy,
or sampling a random action (from a uniform distribution over the action space)
or by adding noise to the deterministic output.
:param action_noise: Action noise that will be used for exploration
Required for deterministic policy (e.g. TD3). This can also be used
in addition to the stochastic policy for SAC.
:param learning_starts: Number of steps before learning for the warm-up phase.
:param n_envs:
:return: action to take in the environment
and scaled action that will be stored in the replay buffer.
The two differs when the action space is not normalized (bounds are not [-1, 1]).
"""
# Select action randomly or according to policy
if self.num_timesteps < learning_starts and not (self.use_sde and self.use_sde_at_warmup):
# Warmup phase
unscaled_action = np.array([self.action_space.sample() for _ in range(n_envs)])
else:
# Note: when using continuous actions,
# we assume that the policy uses tanh to scale the action
# We use non-deterministic action in the case of SAC, for TD3, it does not matter
unscaled_action, _ = self.predict(self._last_obs, deterministic=False)
# Rescale the action from [low, high] to [-1, 1]
if isinstance(self.action_space, spaces.Box):
scaled_action = self.policy.scale_action(unscaled_action)
# Add noise to the action (improve exploration)
if action_noise is not None:
scaled_action = np.clip(scaled_action + action_noise(), -1, 1)
# We store the scaled action in the buffer
buffer_action = scaled_action
action = self.policy.unscale_action(scaled_action)
else:
# Discrete case, no need to normalize or clip
buffer_action = unscaled_action
action = buffer_action
return action, buffer_action
def _dump_logs(self) -> None:
"""
Write log.
"""
time_elapsed = max((time.time_ns() - self.start_time) / 1e9, sys.float_info.epsilon)
fps = int((self.num_timesteps - self._num_timesteps_at_start) / time_elapsed)
self.logger.record("time/episodes", self._episode_num, exclude="tensorboard")
if len(self.ep_info_buffer) > 0 and len(self.ep_info_buffer[0]) > 0:
self.logger.record("rollout/ep_rew_mean", safe_mean([ep_info["r"] for ep_info in self.ep_info_buffer]))
self.logger.record("rollout/ep_len_mean", safe_mean([ep_info["l"] for ep_info in self.ep_info_buffer]))
self.logger.record("time/fps", fps)
self.logger.record("time/time_elapsed", int(time_elapsed), exclude="tensorboard")
self.logger.record("time/total_timesteps", self.num_timesteps, exclude="tensorboard")
if self.use_sde or self.use_pca:
self.logger.record("train/std", (self.actor.get_std()).mean().item())
if len(self.ep_success_buffer) > 0:
self.logger.record("rollout/success_rate", safe_mean(self.ep_success_buffer))
# Pass the number of timesteps for tensorboard
self.logger.dump(step=self.num_timesteps)
def _on_step(self) -> None:
"""
Method called after each step in the environment.
It is meant to trigger DQN target network update
but can be used for other purposes
"""
pass
def _store_transition(
self,
replay_buffer: ReplayBuffer,
buffer_action: np.ndarray,
new_obs: Union[np.ndarray, Dict[str, np.ndarray]],
reward: np.ndarray,
dones: np.ndarray,
infos: List[Dict[str, Any]],
) -> None:
"""
Store transition in the replay buffer.
We store the normalized action and the unnormalized observation.
It also handles terminal observations (because VecEnv resets automatically).
:param replay_buffer: Replay buffer object where to store the transition.
:param buffer_action: normalized action
:param new_obs: next observation in the current episode
or first observation of the episode (when dones is True)
:param reward: reward for the current transition
:param dones: Termination signal
:param infos: List of additional information about the transition.
It may contain the terminal observations and information about timeout.
"""
# Store only the unnormalized version
if self._vec_normalize_env is not None:
new_obs_ = self._vec_normalize_env.get_original_obs()
reward_ = self._vec_normalize_env.get_original_reward()
else:
# Avoid changing the original ones
self._last_original_obs, new_obs_, reward_ = self._last_obs, new_obs, reward
# Avoid modification by reference
next_obs = deepcopy(new_obs_)
# As the VecEnv resets automatically, new_obs is already the
# first observation of the next episode
for i, done in enumerate(dones):
if done and infos[i].get("terminal_observation") is not None:
if isinstance(next_obs, dict):
next_obs_ = infos[i]["terminal_observation"]
# VecNormalize normalizes the terminal observation
if self._vec_normalize_env is not None:
next_obs_ = self._vec_normalize_env.unnormalize_obs(next_obs_)
# Replace next obs for the correct envs
for key in next_obs.keys():
next_obs[key][i] = next_obs_[key]
else:
next_obs[i] = infos[i]["terminal_observation"]
# VecNormalize normalizes the terminal observation
if self._vec_normalize_env is not None:
next_obs[i] = self._vec_normalize_env.unnormalize_obs(next_obs[i, :])
replay_buffer.add(
self._last_original_obs,
next_obs,
buffer_action,
reward_,
dones,
infos,
)
self._last_obs = new_obs
# Save the unnormalized observation
if self._vec_normalize_env is not None:
self._last_original_obs = new_obs_
def collect_rollouts(
self,
env: VecEnv,
callback: BaseCallback,
train_freq: TrainFreq,
replay_buffer: ReplayBuffer,
action_noise: Optional[ActionNoise] = None,
learning_starts: int = 0,
log_interval: Optional[int] = None,
) -> RolloutReturn:
"""
Collect experiences and store them into a ``ReplayBuffer``.
:param env: The training environment
:param callback: Callback that will be called at each step
(and at the beginning and end of the rollout)
:param train_freq: How much experience to collect
by doing rollouts of current policy.
Either ``TrainFreq(<n>, TrainFrequencyUnit.STEP)``
or ``TrainFreq(<n>, TrainFrequencyUnit.EPISODE)``
with ``<n>`` being an integer greater than 0.
:param action_noise: Action noise that will be used for exploration
Required for deterministic policy (e.g. TD3). This can also be used
in addition to the stochastic policy for SAC.
:param learning_starts: Number of steps before learning for the warm-up phase.
:param replay_buffer:
:param log_interval: Log data every ``log_interval`` episodes
:return:
"""
# Switch to eval mode (this affects batch norm / dropout)
self.policy.set_training_mode(False)
num_collected_steps, num_collected_episodes = 0, 0
assert isinstance(env, VecEnv), "You must pass a VecEnv"
assert train_freq.frequency > 0, "Should at least collect one step or episode."
if env.num_envs > 1:
assert train_freq.unit == TrainFrequencyUnit.STEP, "You must use only one env when doing episodic training."
# Vectorize action noise if needed
if action_noise is not None and env.num_envs > 1 and not isinstance(action_noise, VectorizedActionNoise):
action_noise = VectorizedActionNoise(action_noise, env.num_envs)
if self.use_sde or self.use_pca:
self.actor.reset_noise(env.num_envs)
callback.on_rollout_start()
continue_training = True
while should_collect_more_steps(train_freq, num_collected_steps, num_collected_episodes):
if (self.use_sde or self.use_pca) and self.sde_sample_freq > 0 and num_collected_steps % self.sde_sample_freq == 0:
# Sample a new noise matrix
self.actor.reset_noise(env.num_envs)
# Select action randomly or according to policy
actions, buffer_actions = self._sample_action(learning_starts, action_noise, env.num_envs)
# Rescale and perform action
new_obs, rewards, dones, infos = env.step(actions)
self.num_timesteps += env.num_envs
num_collected_steps += 1
# Give access to local variables
callback.update_locals(locals())
# Only stop training if return value is False, not when it is None.
if callback.on_step() is False:
return RolloutReturn(num_collected_steps * env.num_envs, num_collected_episodes, continue_training=False)
# Retrieve reward and episode length if using Monitor wrapper
self._update_info_buffer(infos, dones)
# Store data in replay buffer (normalized action and unnormalized observation)
self._store_transition(replay_buffer, buffer_actions, new_obs, rewards, dones, infos)
self._update_current_progress_remaining(self.num_timesteps, self._total_timesteps)
# For DQN, check if the target network should be updated
# and update the exploration schedule
# For SAC/TD3, the update is dones as the same time as the gradient update
# see https://github.com/hill-a/stable-baselines/issues/900
self._on_step()
for idx, done in enumerate(dones):
if done:
# Update stats
num_collected_episodes += 1
self._episode_num += 1
if action_noise is not None:
kwargs = dict(indices=[idx]) if env.num_envs > 1 else {}
action_noise.reset(**kwargs)
# Log training infos
if log_interval is not None and self._episode_num % log_interval == 0:
self._dump_logs()
callback.on_rollout_end()
return RolloutReturn(num_collected_steps * env.num_envs, num_collected_episodes, continue_training)
@@ -0,0 +1,265 @@
from stable_baselines3.common.on_policy_algorithm import *
class BetterOnPolicyAlgorithm(OnPolicyAlgorithm):
"""
The base for On-Policy algorithms (ex: A2C/PPO).
:param policy: The policy model to use (MlpPolicy, CnnPolicy, ...)
:param env: The environment to learn from (if registered in Gym, can be str)
:param learning_rate: The learning rate, it can be a function
of the current progress remaining (from 1 to 0)
:param n_steps: The number of steps to run for each environment per update
(i.e. batch size is n_steps * n_env where n_env is number of environment copies running in parallel)
:param gamma: Discount factor
:param gae_lambda: Factor for trade-off of bias vs variance for Generalized Advantage Estimator.
Equivalent to classic advantage when set to 1.
:param ent_coef: Entropy coefficient for the loss calculation
:param vf_coef: Value function coefficient for the loss calculation
:param max_grad_norm: The maximum value for the gradient clipping
:param use_sde: Whether to use generalized State Dependent Exploration (gSDE)
instead of action noise exploration (default: False)
:param sde_sample_freq: Sample a new noise matrix every n steps when using gSDE
Default: -1 (only sample at the beginning of the rollout)
:param stats_window_size: Window size for the rollout logging, specifying the number of episodes to average
the reported success rate, mean episode length, and mean reward over
:param tensorboard_log: the log location for tensorboard (if None, no logging)
:param monitor_wrapper: When creating an environment, whether to wrap it
or not in a Monitor wrapper.
:param policy_kwargs: additional arguments to be passed to the policy on creation
:param verbose: Verbosity level: 0 for no output, 1 for info messages (such as device or wrappers used), 2 for
debug messages
:param seed: Seed for the pseudo random generators
:param device: Device (cpu, cuda, ...) on which the code should be run.
Setting it to auto, the code will be run on the GPU if possible.
:param _init_setup_model: Whether or not to build the network at the creation of the instance
:param supported_action_spaces: The action spaces supported by the algorithm.
"""
def __init__(
self,
policy: Union[str, Type[ActorCriticPolicy]],
env: Union[GymEnv, str],
learning_rate: Union[float, Schedule],
n_steps: int,
gamma: float,
gae_lambda: float,
ent_coef: float,
vf_coef: float,
max_grad_norm: float,
use_sde: bool,
sde_sample_freq: int,
use_pca: bool,
stats_window_size: int = 100,
tensorboard_log: Optional[str] = None,
monitor_wrapper: bool = True,
policy_kwargs: Optional[Dict[str, Any]] = None,
verbose: int = 0,
seed: Optional[int] = None,
device: Union[th.device, str] = "auto",
_init_setup_model: bool = True,
supported_action_spaces: Optional[Tuple[spaces.Space, ...]] = None,
):
assert not (use_sde and use_pca)
self.use_pca = use_pca
super().__init__(
policy=policy,
env=env,
learning_rate=learning_rate,
n_steps=n_steps,
gamma=gamma,
gae_lambda=gae_lambda,
ent_coef=ent_coef,
vf_coef=vf_coef,
max_grad_norm=max_grad_norm,
policy_kwargs=policy_kwargs,
verbose=verbose,
device=device,
use_sde=use_sde,
sde_sample_freq=sde_sample_freq,
# support_multi_env=True,
seed=seed,
stats_window_size=stats_window_size,
tensorboard_log=tensorboard_log,
supported_action_spaces=supported_action_spaces,
monitor_wrapper=monitor_wrapper,
_init_setup_model=_init_setup_model
)
def _setup_model(self) -> None:
self._setup_lr_schedule()
self.set_random_seed(self.seed)
buffer_cls = DictRolloutBuffer if isinstance(self.observation_space, spaces.Dict) else RolloutBuffer
self.rollout_buffer = buffer_cls(
self.n_steps,
self.observation_space,
self.action_space,
device=self.device,
gamma=self.gamma,
gae_lambda=self.gae_lambda,
n_envs=self.n_envs,
)
self.policy = self.policy_class( # pytype:disable=not-instantiable
self.observation_space,
self.action_space,
self.lr_schedule,
use_sde=self.use_sde,
use_pca=self.use_pca,
**self.policy_kwargs # pytype:disable=not-instantiable
)
self.policy = self.policy.to(self.device)
def collect_rollouts(
self,
env: VecEnv,
callback: BaseCallback,
rollout_buffer: RolloutBuffer,
n_rollout_steps: int,
) -> bool:
"""
Collect experiences using the current policy and fill a ``RolloutBuffer``.
The term rollout here refers to the model-free notion and should not
be used with the concept of rollout used in model-based RL or planning.
:param env: The training environment
:param callback: Callback that will be called at each step
(and at the beginning and end of the rollout)
:param rollout_buffer: Buffer to fill with rollouts
:param n_rollout_steps: Number of experiences to collect per environment
:return: True if function returned with at least `n_rollout_steps`
collected, False if callback terminated rollout prematurely.
"""
assert self._last_obs is not None, "No previous observation was provided"
# Switch to eval mode (this affects batch norm / dropout)
self.policy.set_training_mode(False)
n_steps = 0
rollout_buffer.reset()
# Sample new weights for the state dependent exploration
if self.use_sde:
self.policy.reset_noise(env.num_envs)
callback.on_rollout_start()
while n_steps < n_rollout_steps:
if self.use_sde and self.sde_sample_freq > 0 and n_steps % self.sde_sample_freq == 0:
# Sample a new noise matrix
self.policy.reset_noise(env.num_envs)
with th.no_grad():
# Convert to pytorch tensor or to TensorDict
obs_tensor = obs_as_tensor(self._last_obs, self.device)
actions, values, log_probs = self.policy(obs_tensor)
actions = actions.cpu().numpy()
# Rescale and perform action
clipped_actions = actions
# Clip the actions to avoid out of bound error
if isinstance(self.action_space, spaces.Box):
clipped_actions = np.clip(actions, self.action_space.low, self.action_space.high)
new_obs, rewards, dones, infos = env.step(clipped_actions)
self.num_timesteps += env.num_envs
# Give access to local variables
callback.update_locals(locals())
if callback.on_step() is False:
return False
self._update_info_buffer(infos)
n_steps += 1
if isinstance(self.action_space, spaces.Discrete):
# Reshape in case of discrete action
actions = actions.reshape(-1, 1)
# Handle timeout by bootstraping with value function
# see GitHub issue #633
for idx, done in enumerate(dones):
if (
done
and infos[idx].get("terminal_observation") is not None
and infos[idx].get("TimeLimit.truncated", False)
):
terminal_obs = self.policy.obs_to_tensor(infos[idx]["terminal_observation"])[0]
with th.no_grad():
terminal_value = self.policy.predict_values(terminal_obs)[0]
rewards[idx] += self.gamma * terminal_value
rollout_buffer.add(self._last_obs, actions, rewards, self._last_episode_starts, values, log_probs)
self._last_obs = new_obs
self._last_episode_starts = dones
with th.no_grad():
# Compute value for the last timestep
values = self.policy.predict_values(obs_as_tensor(new_obs, self.device))
rollout_buffer.compute_returns_and_advantage(last_values=values, dones=dones)
callback.on_rollout_end()
return True
def train(self) -> None:
"""
Consume current rollout data and update policy parameters.
Implemented by individual algorithms.
"""
raise NotImplementedError
def learn(
self: SelfOnPolicyAlgorithm,
total_timesteps: int,
callback: MaybeCallback = None,
log_interval: int = 1,
tb_log_name: str = "OnPolicyAlgorithm",
reset_num_timesteps: bool = True,
progress_bar: bool = False,
) -> SelfOnPolicyAlgorithm:
iteration = 0
total_timesteps, callback = self._setup_learn(
total_timesteps,
callback,
reset_num_timesteps,
tb_log_name,
progress_bar,
)
callback.on_training_start(locals(), globals())
while self.num_timesteps < total_timesteps:
continue_training = self.collect_rollouts(self.env, callback, self.rollout_buffer, n_rollout_steps=self.n_steps)
if continue_training is False:
break
iteration += 1
self._update_current_progress_remaining(self.num_timesteps, total_timesteps)
# Display training infos
if log_interval is not None and iteration % log_interval == 0:
time_elapsed = max((time.time_ns() - self.start_time) / 1e9, sys.float_info.epsilon)
fps = int((self.num_timesteps - self._num_timesteps_at_start) / time_elapsed)
self.logger.record("time/iterations", iteration, exclude="tensorboard")
if len(self.ep_info_buffer) > 0 and len(self.ep_info_buffer[0]) > 0:
self.logger.record("rollout/ep_rew_mean", safe_mean([ep_info["r"] for ep_info in self.ep_info_buffer]))
self.logger.record("rollout/ep_len_mean", safe_mean([ep_info["l"] for ep_info in self.ep_info_buffer]))
self.logger.record("time/fps", fps)
self.logger.record("time/time_elapsed", int(time_elapsed), exclude="tensorboard")
self.logger.record("time/total_timesteps", self.num_timesteps, exclude="tensorboard")
self.logger.dump(step=self.num_timesteps)
self.train()
callback.on_training_end()
return self
def _get_torch_save_params(self) -> Tuple[List[str], List[str]]:
state_dicts = ["policy", "policy.optimizer"]
return state_dicts, []
File diff suppressed because it is too large Load Diff
+5
View File
@@ -0,0 +1,5 @@
from metastable_baselines2.ppo.ppo import PPO
from stable_baselines3.ppo.policies import CnnPolicy, MlpPolicy, MultiInputPolicy
__all__ = ["CnnPolicy", "MlpPolicy", "MultiInputPolicy", "PPO"]
+325
View File
@@ -0,0 +1,325 @@
import warnings
from typing import Any, ClassVar, Dict, Optional, Type, TypeVar, Union
import numpy as np
import torch as th
from gymnasium import spaces
from torch.nn import functional as F
from stable_baselines3.common.buffers import RolloutBuffer
from ..common.on_policy_algorithm import BetterOnPolicyAlgorithm
from ..common.policies import ActorCriticPolicy, BasePolicy
from stable_baselines3.common.type_aliases import GymEnv, MaybeCallback, Schedule
from stable_baselines3.common.utils import explained_variance, get_schedule_fn
SelfPPO = TypeVar("SelfPPO", bound="PPO")
class PPO(BetterOnPolicyAlgorithm):
"""
Proximal Policy Optimization algorithm (PPO) (clip version)
Paper: https://arxiv.org/abs/1707.06347
Code: This implementation borrows code from OpenAI Spinning Up (https://github.com/openai/spinningup/)
https://github.com/ikostrikov/pytorch-a2c-ppo-acktr-gail and
Stable Baselines (PPO2 from https://github.com/hill-a/stable-baselines)
Introduction to PPO: https://spinningup.openai.com/en/latest/algorithms/ppo.html
:param policy: The policy model to use (MlpPolicy, CnnPolicy, ...)
:param env: The environment to learn from (if registered in Gym, can be str)
:param learning_rate: The learning rate, it can be a function
of the current progress remaining (from 1 to 0)
:param n_steps: The number of steps to run for each environment per update
(i.e. rollout buffer size is n_steps * n_envs where n_envs is number of environment copies running in parallel)
NOTE: n_steps * n_envs must be greater than 1 (because of the advantage normalization)
See https://github.com/pytorch/pytorch/issues/29372
:param batch_size: Minibatch size
:param n_epochs: Number of epoch when optimizing the surrogate loss
:param gamma: Discount factor
:param gae_lambda: Factor for trade-off of bias vs variance for Generalized Advantage Estimator
:param clip_range: Clipping parameter, it can be a function of the current progress
remaining (from 1 to 0).
:param clip_range_vf: Clipping parameter for the value function,
it can be a function of the current progress remaining (from 1 to 0).
This is a parameter specific to the OpenAI implementation. If None is passed (default),
no clipping will be done on the value function.
IMPORTANT: this clipping depends on the reward scaling.
:param normalize_advantage: Whether to normalize or not the advantage
:param ent_coef: Entropy coefficient for the loss calculation
:param vf_coef: Value function coefficient for the loss calculation
:param max_grad_norm: The maximum value for the gradient clipping
:param use_sde: Whether to use generalized State Dependent Exploration (gSDE)
instead of action noise exploration (default: False)
:param sde_sample_freq: Sample a new noise matrix every n steps when using gSDE
Default: -1 (only sample at the beginning of the rollout)
:param use_pca: Wether to use Prior Conditioned Annealing
:param rollout_buffer_class: Rollout buffer class to use. If ``None``, it will be automatically selected.
:param rollout_buffer_kwargs: Keyword arguments to pass to the rollout buffer on creation
:param target_kl: Limit the KL divergence between updates,
because the clipping is not enough to prevent large update
see issue #213 (cf https://github.com/hill-a/stable-baselines/issues/213)
By default, there is no limit on the kl div.
:param stats_window_size: Window size for the rollout logging, specifying the number of episodes to average
the reported success rate, mean episode length, and mean reward over
:param tensorboard_log: the log location for tensorboard (if None, no logging)
:param policy_kwargs: additional arguments to be passed to the policy on creation
:param verbose: Verbosity level: 0 for no output, 1 for info messages (such as device or wrappers used), 2 for
debug messages
:param seed: Seed for the pseudo random generators
:param device: Device (cpu, cuda, ...) on which the code should be run.
Setting it to auto, the code will be run on the GPU if possible.
:param _init_setup_model: Whether or not to build the network at the creation of the instance
"""
policy_aliases: ClassVar[Dict[str, Type[BasePolicy]]] = {
"MlpPolicy": ActorCriticPolicy
}
def __init__(
self,
policy: Union[str, Type[ActorCriticPolicy]],
env: Union[GymEnv, str],
learning_rate: Union[float, Schedule] = 3e-4,
n_steps: int = 2048,
batch_size: int = 64,
n_epochs: int = 10,
gamma: float = 0.99,
gae_lambda: float = 0.95,
clip_range: Union[float, Schedule] = 0.2,
clip_range_vf: Union[None, float, Schedule] = None,
normalize_advantage: bool = True,
ent_coef: float = 0.0,
vf_coef: float = 0.5,
max_grad_norm: float = 0.5,
use_sde: bool = False,
sde_sample_freq: int = -1,
use_pca: bool = False,
rollout_buffer_class: Optional[Type[RolloutBuffer]] = None,
rollout_buffer_kwargs: Optional[Dict[str, Any]] = None,
target_kl: Optional[float] = None,
stats_window_size: int = 100,
tensorboard_log: Optional[str] = None,
policy_kwargs: Optional[Dict[str, Any]] = None,
verbose: int = 0,
seed: Optional[int] = None,
device: Union[th.device, str] = "auto",
_init_setup_model: bool = True,
):
super().__init__(
policy,
env,
learning_rate=learning_rate,
n_steps=n_steps,
gamma=gamma,
gae_lambda=gae_lambda,
ent_coef=ent_coef,
vf_coef=vf_coef,
max_grad_norm=max_grad_norm,
use_sde=use_sde,
sde_sample_freq=sde_sample_freq,
use_pca=use_pca,
rollout_buffer_class=rollout_buffer_class,
rollout_buffer_kwargs=rollout_buffer_kwargs,
stats_window_size=stats_window_size,
tensorboard_log=tensorboard_log,
policy_kwargs=policy_kwargs,
verbose=verbose,
device=device,
seed=seed,
_init_setup_model=False,
supported_action_spaces=(
spaces.Box,
spaces.Discrete,
spaces.MultiDiscrete,
spaces.MultiBinary,
),
)
print('[i] Using metastable version of PPO')
# Sanity check, otherwise it will lead to noisy gradient and NaN
# because of the advantage normalization
if normalize_advantage:
assert (
batch_size > 1
), "`batch_size` must be greater than 1. See https://github.com/DLR-RM/stable-baselines3/issues/440"
if self.env is not None:
# Check that `n_steps * n_envs > 1` to avoid NaN
# when doing advantage normalization
buffer_size = self.env.num_envs * self.n_steps
assert buffer_size > 1 or (
not normalize_advantage
), f"`n_steps * n_envs` must be greater than 1. Currently n_steps={self.n_steps} and n_envs={self.env.num_envs}"
# Check that the rollout buffer size is a multiple of the mini-batch size
untruncated_batches = buffer_size // batch_size
if buffer_size % batch_size > 0:
warnings.warn(
f"You have specified a mini-batch size of {batch_size},"
f" but because the `RolloutBuffer` is of size `n_steps * n_envs = {buffer_size}`,"
f" after every {untruncated_batches} untruncated mini-batches,"
f" there will be a truncated mini-batch of size {buffer_size % batch_size}\n"
f"We recommend using a `batch_size` that is a factor of `n_steps * n_envs`.\n"
f"Info: (n_steps={self.n_steps} and n_envs={self.env.num_envs})"
)
self.batch_size = batch_size
self.n_epochs = n_epochs
self.clip_range = clip_range
self.clip_range_vf = clip_range_vf
self.normalize_advantage = normalize_advantage
self.target_kl = target_kl
if _init_setup_model:
self._setup_model()
def _setup_model(self) -> None:
super()._setup_model()
# Initialize schedules for policy/value clipping
self.clip_range = get_schedule_fn(self.clip_range)
if self.clip_range_vf is not None:
if isinstance(self.clip_range_vf, (float, int)):
assert self.clip_range_vf > 0, "`clip_range_vf` must be positive, " "pass `None` to deactivate vf clipping"
self.clip_range_vf = get_schedule_fn(self.clip_range_vf)
def train(self) -> None:
"""
Update policy using the currently gathered rollout buffer.
"""
# Switch to train mode (this affects batch norm / dropout)
self.policy.set_training_mode(True)
# Update optimizer learning rate
self._update_learning_rate(self.policy.optimizer)
# Compute current clip range
clip_range = self.clip_range(self._current_progress_remaining)
# Optional: clip range for the value function
if self.clip_range_vf is not None:
clip_range_vf = self.clip_range_vf(self._current_progress_remaining)
entropy_losses = []
pg_losses, value_losses = [], []
clip_fractions = []
continue_training = True
# train for n_epochs epochs
for epoch in range(self.n_epochs):
approx_kl_divs = []
# Do a complete pass on the rollout buffer
for rollout_data in self.rollout_buffer.get(self.batch_size):
actions = rollout_data.actions
if isinstance(self.action_space, spaces.Discrete):
# Convert discrete action from float to long
actions = rollout_data.actions.long().flatten()
# Re-sample the noise matrix because the log_std has changed
if self.use_sde or self.use_pca:
self.policy.reset_noise(self.batch_size)
values, log_prob, entropy = self.policy.evaluate_actions(rollout_data.observations, actions)
values = values.flatten()
# Normalize advantage
advantages = rollout_data.advantages
# Normalization does not make sense if mini batchsize == 1, see GH issue #325
if self.normalize_advantage and len(advantages) > 1:
advantages = (advantages - advantages.mean()) / (advantages.std() + 1e-8)
# ratio between old and new policy, should be one at the first iteration
ratio = th.exp(log_prob - rollout_data.old_log_prob)
# clipped surrogate loss
policy_loss_1 = advantages * ratio
policy_loss_2 = advantages * th.clamp(ratio, 1 - clip_range, 1 + clip_range)
policy_loss = -th.min(policy_loss_1, policy_loss_2).mean()
# Logging
pg_losses.append(policy_loss.item())
clip_fraction = th.mean((th.abs(ratio - 1) > clip_range).float()).item()
clip_fractions.append(clip_fraction)
if self.clip_range_vf is None:
# No clipping
values_pred = values
else:
# Clip the difference between old and new value
# NOTE: this depends on the reward scaling
values_pred = rollout_data.old_values + th.clamp(
values - rollout_data.old_values, -clip_range_vf, clip_range_vf
)
# Value loss using the TD(gae_lambda) target
value_loss = F.mse_loss(rollout_data.returns, values_pred)
value_losses.append(value_loss.item())
# Entropy loss favor exploration
if entropy is None:
# Approximate entropy when no analytical form
entropy_loss = -th.mean(-log_prob)
else:
entropy_loss = -th.mean(entropy)
entropy_losses.append(entropy_loss.item())
loss = policy_loss + self.ent_coef * entropy_loss + self.vf_coef * value_loss
# Calculate approximate form of reverse KL Divergence for early stopping
# see issue #417: https://github.com/DLR-RM/stable-baselines3/issues/417
# and discussion in PR #419: https://github.com/DLR-RM/stable-baselines3/pull/419
# and Schulman blog: http://joschu.net/blog/kl-approx.html
with th.no_grad():
log_ratio = log_prob - rollout_data.old_log_prob
approx_kl_div = th.mean((th.exp(log_ratio) - 1) - log_ratio).cpu().numpy()
approx_kl_divs.append(approx_kl_div)
if self.target_kl is not None and approx_kl_div > 1.5 * self.target_kl:
continue_training = False
if self.verbose >= 1:
print(f"Early stopping at step {epoch} due to reaching max kl: {approx_kl_div:.2f}")
break
# Optimization step
self.policy.optimizer.zero_grad()
loss.backward()
# Clip grad norm
th.nn.utils.clip_grad_norm_(self.policy.parameters(), self.max_grad_norm)
self.policy.optimizer.step()
self._n_updates += 1
if not continue_training:
break
explained_var = explained_variance(self.rollout_buffer.values.flatten(), self.rollout_buffer.returns.flatten())
# Logs
self.logger.record("train/entropy_loss", np.mean(entropy_losses))
self.logger.record("train/policy_gradient_loss", np.mean(pg_losses))
self.logger.record("train/value_loss", np.mean(value_losses))
self.logger.record("train/approx_kl", np.mean(approx_kl_divs))
self.logger.record("train/clip_fraction", np.mean(clip_fractions))
self.logger.record("train/loss", loss.item())
self.logger.record("train/explained_variance", explained_var)
if hasattr(self.policy, "log_std"):
self.logger.record("train/std", th.exp(self.policy.log_std).mean().item())
self.logger.record("train/n_updates", self._n_updates, exclude="tensorboard")
self.logger.record("train/clip_range", clip_range)
if self.clip_range_vf is not None:
self.logger.record("train/clip_range_vf", clip_range_vf)
def learn(
self: SelfPPO,
total_timesteps: int,
callback: MaybeCallback = None,
log_interval: int = 1,
tb_log_name: str = "PPO",
reset_num_timesteps: bool = True,
progress_bar: bool = False,
) -> SelfPPO:
return super().learn(
total_timesteps=total_timesteps,
callback=callback,
log_interval=log_interval,
tb_log_name=tb_log_name,
reset_num_timesteps=reset_num_timesteps,
progress_bar=progress_bar,
)
+1
View File
@@ -0,0 +1 @@
from metastable_baselines2.sac.sac import SAC
+331
View File
@@ -0,0 +1,331 @@
from typing import Any, ClassVar, Dict, List, Optional, Tuple, Type, TypeVar, Union
import numpy as np
import torch as th
from gymnasium import spaces
from torch.nn import functional as F
from stable_baselines3.common.buffers import ReplayBuffer
from stable_baselines3.common.noise import ActionNoise
# from stable_baselines3.common.off_policy_algorithm import OffPolicyAlgorithm
from ..common.off_policy_algorithm import BetterOffPolicyAlgorithm
from stable_baselines3.common.policies import BasePolicy, ContinuousCritic
from stable_baselines3.common.type_aliases import GymEnv, MaybeCallback, Schedule
from stable_baselines3.common.utils import get_parameters_by_name, polyak_update
from ..common.policies import SACMlpPolicy, SACPolicy, Actor #, CnnPolicy, MlpPolicy, MultiInputPolicy, SACPolicy
SelfSAC = TypeVar("SelfSAC", bound="SAC")
class SAC(BetterOffPolicyAlgorithm):
"""
Soft Actor-Critic (SAC)
Off-Policy Maximum Entropy Deep Reinforcement Learning with a Stochastic Actor,
This implementation borrows code from original implementation (https://github.com/haarnoja/sac)
from OpenAI Spinning Up (https://github.com/openai/spinningup), from the softlearning repo
(https://github.com/rail-berkeley/softlearning/)
and from Stable Baselines (https://github.com/hill-a/stable-baselines)
Paper: https://arxiv.org/abs/1801.01290
Introduction to SAC: https://spinningup.openai.com/en/latest/algorithms/sac.html
Note: we use double q target and not value target as discussed
in https://github.com/hill-a/stable-baselines/issues/270
:param policy: The policy model to use (MlpPolicy, CnnPolicy, ...)
:param env: The environment to learn from (if registered in Gym, can be str)
:param learning_rate: learning rate for adam optimizer,
the same learning rate will be used for all networks (Q-Values, Actor and Value function)
it can be a function of the current progress remaining (from 1 to 0)
:param buffer_size: size of the replay buffer
:param learning_starts: how many steps of the model to collect transitions for before learning starts
:param batch_size: Minibatch size for each gradient update
:param tau: the soft update coefficient ("Polyak update", between 0 and 1)
:param gamma: the discount factor
:param train_freq: Update the model every ``train_freq`` steps. Alternatively pass a tuple of frequency and unit
like ``(5, "step")`` or ``(2, "episode")``.
:param gradient_steps: How many gradient steps to do after each rollout (see ``train_freq``)
Set to ``-1`` means to do as many gradient steps as steps done in the environment
during the rollout.
:param action_noise: the action noise type (None by default), this can help
for hard exploration problem. Cf common.noise for the different action noise type.
:param replay_buffer_class: Replay buffer class to use (for instance ``HerReplayBuffer``).
If ``None``, it will be automatically selected.
:param replay_buffer_kwargs: Keyword arguments to pass to the replay buffer on creation.
:param optimize_memory_usage: Enable a memory efficient variant of the replay buffer
at a cost of more complexity.
See https://github.com/DLR-RM/stable-baselines3/issues/37#issuecomment-637501195
:param ent_coef: Entropy regularization coefficient. (Equivalent to
inverse of reward scale in the original SAC paper.) Controlling exploration/exploitation trade-off.
Set it to 'auto' to learn it automatically (and 'auto_0.1' for using 0.1 as initial value)
:param target_update_interval: update the target network every ``target_network_update_freq``
gradient steps.
:param target_entropy: target entropy when learning ``ent_coef`` (``ent_coef = 'auto'``)
:param use_sde: Whether to use generalized State Dependent Exploration (gSDE)
instead of action noise exploration (default: False)
:param sde_sample_freq: Sample a new noise matrix every n steps when using gSDE
Default: -1 (only sample at the beginning of the rollout)
:param use_sde_at_warmup: Whether to use gSDE instead of uniform sampling
during the warm up phase (before learning starts)
:param stats_window_size: Window size for the rollout logging, specifying the number of episodes to average
the reported success rate, mean episode length, and mean reward over
:param tensorboard_log: the log location for tensorboard (if None, no logging)
:param policy_kwargs: additional arguments to be passed to the policy on creation
:param verbose: Verbosity level: 0 for no output, 1 for info messages (such as device or wrappers used), 2 for
debug messages
:param seed: Seed for the pseudo random generators
:param device: Device (cpu, cuda, ...) on which the code should be run.
Setting it to auto, the code will be run on the GPU if possible.
:param _init_setup_model: Whether or not to build the network at the creation of the instance
"""
policy_aliases: ClassVar[Dict[str, Type[BasePolicy]]] = {
"MlpPolicy": SACMlpPolicy,
"SACPolicy": SACPolicy,
}
policy: SACPolicy
actor: Actor
critic: ContinuousCritic
critic_target: ContinuousCritic
def __init__(
self,
policy: Union[str, Type[SACPolicy]],
env: Union[GymEnv, str],
learning_rate: Union[float, Schedule] = 3e-4,
buffer_size: int = 1_000_000, # 1e6
learning_starts: int = 100,
batch_size: int = 256,
tau: float = 0.005,
gamma: float = 0.99,
train_freq: Union[int, Tuple[int, str]] = 1,
gradient_steps: int = 1,
action_noise: Optional[ActionNoise] = None,
replay_buffer_class: Optional[Type[ReplayBuffer]] = None,
replay_buffer_kwargs: Optional[Dict[str, Any]] = None,
optimize_memory_usage: bool = False,
ent_coef: Union[str, float] = "auto",
target_update_interval: int = 1,
target_entropy: Union[str, float] = "auto",
use_sde: bool = False,
sde_sample_freq: int = -1,
use_sde_at_warmup: bool = False,
use_pca: bool = False,
stats_window_size: int = 100,
tensorboard_log: Optional[str] = None,
policy_kwargs: Optional[Dict[str, Any]] = None,
verbose: int = 0,
seed: Optional[int] = None,
device: Union[th.device, str] = "auto",
_init_setup_model: bool = True,
):
super().__init__(
policy,
env,
learning_rate,
buffer_size,
learning_starts,
batch_size,
tau,
gamma,
train_freq,
gradient_steps,
action_noise,
replay_buffer_class=replay_buffer_class,
replay_buffer_kwargs=replay_buffer_kwargs,
policy_kwargs=policy_kwargs,
stats_window_size=stats_window_size,
tensorboard_log=tensorboard_log,
verbose=verbose,
device=device,
seed=seed,
use_sde=use_sde,
sde_sample_freq=sde_sample_freq,
use_sde_at_warmup=use_sde_at_warmup,
use_pca=use_pca,
optimize_memory_usage=optimize_memory_usage,
supported_action_spaces=(spaces.Box,),
support_multi_env=True,
)
print('[i] Using metastable version of SAC')
self.target_entropy = target_entropy
self.log_ent_coef = None # type: Optional[th.Tensor]
# Entropy coefficient / Entropy temperature
# Inverse of the reward scale
self.ent_coef = ent_coef
self.target_update_interval = target_update_interval
self.ent_coef_optimizer = Optional[th.optim.Adam] = None
if _init_setup_model:
self._setup_model()
def _setup_model(self) -> None:
super()._setup_model()
self._create_aliases()
# Running mean and running var
self.batch_norm_stats = get_parameters_by_name(self.critic, ["running_"])
self.batch_norm_stats_target = get_parameters_by_name(self.critic_target, ["running_"])
# Target entropy is used when learning the entropy coefficient
if self.target_entropy == "auto":
# automatically set target entropy if needed
self.target_entropy = float(-np.prod(self.env.action_space.shape).astype(np.float32)) # type: ignore
else:
# Force conversion
# this will also throw an error for unexpected string
self.target_entropy = float(self.target_entropy)
# The entropy coefficient or entropy can be learned automatically
# see Automating Entropy Adjustment for Maximum Entropy RL section
# of https://arxiv.org/abs/1812.05905
if isinstance(self.ent_coef, str) and self.ent_coef.startswith("auto"):
# Default initial value of ent_coef when learned
init_value = 1.0
if "_" in self.ent_coef:
init_value = float(self.ent_coef.split("_")[1])
assert init_value > 0.0, "The initial value of ent_coef must be greater than 0"
# Note: we optimize the log of the entropy coeff which is slightly different from the paper
# as discussed in https://github.com/rail-berkeley/softlearning/issues/37
self.log_ent_coef = th.log(th.ones(1, device=self.device) * init_value).requires_grad_(True)
self.ent_coef_optimizer = th.optim.Adam([self.log_ent_coef], lr=self.lr_schedule(1))
else:
# Force conversion to float
# this will throw an error if a malformed string (different from 'auto')
# is passed
self.ent_coef_tensor = th.tensor(float(self.ent_coef), device=self.device)
def _create_aliases(self) -> None:
self.actor = self.policy.actor
self.critic = self.policy.critic
self.critic_target = self.policy.critic_target
def train(self, gradient_steps: int, batch_size: int = 64) -> None:
# Switch to train mode (this affects batch norm / dropout)
self.policy.set_training_mode(True)
# Update optimizers learning rate
optimizers = [self.actor.optimizer, self.critic.optimizer]
if self.ent_coef_optimizer is not None:
optimizers += [self.ent_coef_optimizer]
# Update learning rate according to lr schedule
self._update_learning_rate(optimizers)
ent_coef_losses, ent_coefs = [], []
actor_losses, critic_losses = [], []
for gradient_step in range(gradient_steps):
# Sample replay buffer
replay_data = self.replay_buffer.sample(batch_size, env=self._vec_normalize_env) # type: ignore[union-attr]
# We need to sample because `log_std` may have changed between two gradient steps
if self.use_sde:
self.actor.reset_noise()
# Action by the current actor for the sampled state
actions_pi, log_prob = self.actor.action_log_prob(replay_data.observations)
log_prob = log_prob.reshape(-1, 1)
ent_coef_loss = None
if self.ent_coef_optimizer is not None and self.log_ent_coef is not None:
# Important: detach the variable from the graph
# so we don't change it with other losses
# see https://github.com/rail-berkeley/softlearning/issues/60
ent_coef = th.exp(self.log_ent_coef.detach())
ent_coef_loss = -(self.log_ent_coef * (log_prob + self.target_entropy).detach()).mean()
ent_coef_losses.append(ent_coef_loss.item())
else:
ent_coef = self.ent_coef_tensor
ent_coefs.append(ent_coef.item())
# Optimize entropy coefficient, also called
# entropy temperature or alpha in the paper
if ent_coef_loss is not None:
self.ent_coef_optimizer.zero_grad()
ent_coef_loss.backward()
self.ent_coef_optimizer.step()
with th.no_grad():
# Select action according to policy
next_actions, next_log_prob = self.actor.action_log_prob(replay_data.next_observations)
# Compute the next Q values: min over all critics targets
next_q_values = th.cat(self.critic_target(replay_data.next_observations, next_actions), dim=1)
next_q_values, _ = th.min(next_q_values, dim=1, keepdim=True)
# add entropy term
next_q_values = next_q_values - ent_coef * next_log_prob.reshape(-1, 1)
# td error + entropy term
target_q_values = replay_data.rewards + (1 - replay_data.dones) * self.gamma * next_q_values
# Get current Q-values estimates for each critic network
# using action from the replay buffer
current_q_values = self.critic(replay_data.observations, replay_data.actions)
# Compute critic loss
critic_loss = 0.5 * sum(F.mse_loss(current_q, target_q_values) for current_q in current_q_values)
assert isinstance(critic_loss, th.Tensor) # for type checker
critic_losses.append(critic_loss.item()) # type: ignore[union-attr]
# Optimize the critic
self.critic.optimizer.zero_grad()
critic_loss.backward()
self.critic.optimizer.step()
# Compute actor loss
# Alternative: actor_loss = th.mean(log_prob - qf1_pi)
# Min over all critic networks
q_values_pi = th.cat(self.critic(replay_data.observations, actions_pi), dim=1)
min_qf_pi, _ = th.min(q_values_pi, dim=1, keepdim=True)
actor_loss = (ent_coef * log_prob - min_qf_pi).mean()
actor_losses.append(actor_loss.item())
# Optimize the actor
self.actor.optimizer.zero_grad()
actor_loss.backward()
self.actor.optimizer.step()
# Update target networks
if gradient_step % self.target_update_interval == 0:
polyak_update(self.critic.parameters(), self.critic_target.parameters(), self.tau)
# Copy running stats, see GH issue #996
polyak_update(self.batch_norm_stats, self.batch_norm_stats_target, 1.0)
self._n_updates += gradient_steps
self.logger.record("train/n_updates", self._n_updates, exclude="tensorboard")
self.logger.record("train/ent_coef", np.mean(ent_coefs))
self.logger.record("train/actor_loss", np.mean(actor_losses))
self.logger.record("train/critic_loss", np.mean(critic_losses))
if len(ent_coef_losses) > 0:
self.logger.record("train/ent_coef_loss", np.mean(ent_coef_losses))
def learn(
self: SelfSAC,
total_timesteps: int,
callback: MaybeCallback = None,
log_interval: int = 4,
tb_log_name: str = "SAC",
reset_num_timesteps: bool = True,
progress_bar: bool = False,
) -> SelfSAC:
return super().learn(
total_timesteps=total_timesteps,
callback=callback,
log_interval=log_interval,
tb_log_name=tb_log_name,
reset_num_timesteps=reset_num_timesteps,
progress_bar=progress_bar,
)
def _excluded_save_params(self) -> List[str]:
return super()._excluded_save_params() + ["actor", "critic", "critic_target"] # noqa: RUF005
def _get_torch_save_params(self) -> Tuple[List[str], List[str]]:
state_dicts = ["policy", "actor.optimizer", "critic.optimizer"]
if self.ent_coef_optimizer is not None:
saved_pytorch_variables = ["log_ent_coef"]
state_dicts.append("ent_coef_optimizer")
else:
saved_pytorch_variables = ["ent_coef_tensor"]
return state_dicts, saved_pytorch_variables
+2
View File
@@ -0,0 +1,2 @@
from stable_baselines3.ppo.policies import CnnPolicy, MlpPolicy, MultiInputPolicy
from metastable_baselines2.trpl.trpl import TRPL
+1
View File
@@ -0,0 +1 @@
pass