implement REDQ based on original contribution by @Jimenius (#623)

Co-authored-by: Minhui Li
 <limh@lamda.nju.edu.cn>
This commit is contained in:
Yi Su 2022-04-30 09:06:00 -07:00 committed by GitHub
parent 41afc2584a
commit dd16818ce4
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11 changed files with 655 additions and 13 deletions

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@ -34,6 +34,7 @@
- [Deep Deterministic Policy Gradient (DDPG)](https://arxiv.org/pdf/1509.02971.pdf)
- [Twin Delayed DDPG (TD3)](https://arxiv.org/pdf/1802.09477.pdf)
- [Soft Actor-Critic (SAC)](https://arxiv.org/pdf/1812.05905.pdf)
- [Randomized Ensembled Double Q-Learning (REDQ)](https://arxiv.org/pdf/2101.05982.pdf)
- [Discrete Soft Actor-Critic (SAC-Discrete)](https://arxiv.org/pdf/1910.07207.pdf)
- Vanilla Imitation Learning
- [Batch-Constrained deep Q-Learning (BCQ)](https://arxiv.org/pdf/1812.02900.pdf)

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@ -96,6 +96,11 @@ Off-policy
:undoc-members:
:show-inheritance:
.. autoclass:: tianshou.policy.REDQPolicy
:members:
:undoc-members:
:show-inheritance:
.. autoclass:: tianshou.policy.DiscreteSACPolicy
:members:
:undoc-members:

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@ -25,6 +25,7 @@ Welcome to Tianshou!
* :class:`~tianshou.policy.DDPGPolicy` `Deep Deterministic Policy Gradient <https://arxiv.org/pdf/1509.02971.pdf>`_
* :class:`~tianshou.policy.TD3Policy` `Twin Delayed DDPG <https://arxiv.org/pdf/1802.09477.pdf>`_
* :class:`~tianshou.policy.SACPolicy` `Soft Actor-Critic <https://arxiv.org/pdf/1812.05905.pdf>`_
* :class:`~tianshou.policy.REDQPolicy` `Randomized Ensembled Double Q-Learning <https://arxiv.org/pdf/2101.05982.pdf>`_
* :class:`~tianshou.policy.DiscreteSACPolicy` `Discrete Soft Actor-Critic <https://arxiv.org/pdf/1910.07207.pdf>`_
* :class:`~tianshou.policy.ImitationPolicy` Imitation Learning
* :class:`~tianshou.policy.BCQPolicy` `Batch-Constrained deep Q-Learning <https://arxiv.org/pdf/1812.02900.pdf>`_

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@ -157,3 +157,4 @@ Nvidia
Enduro
Qbert
Seaquest
subnets

192
examples/mujoco/mujoco_redq.py Executable file
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@ -0,0 +1,192 @@
#!/usr/bin/env python3
import argparse
import datetime
import os
import pprint
import gym
import numpy as np
import torch
from torch.utils.tensorboard import SummaryWriter
from tianshou.data import Collector, ReplayBuffer, VectorReplayBuffer
from tianshou.env import SubprocVectorEnv
from tianshou.policy import REDQPolicy
from tianshou.trainer import offpolicy_trainer
from tianshou.utils import TensorboardLogger
from tianshou.utils.net.common import EnsembleLinear, Net
from tianshou.utils.net.continuous import ActorProb, Critic
def get_args():
parser = argparse.ArgumentParser()
parser.add_argument('--task', type=str, default='Ant-v3')
parser.add_argument('--seed', type=int, default=0)
parser.add_argument('--buffer-size', type=int, default=1000000)
parser.add_argument('--hidden-sizes', type=int, nargs='*', default=[256, 256])
parser.add_argument('--ensemble-size', type=int, default=10)
parser.add_argument('--subset-size', type=int, default=2)
parser.add_argument('--actor-lr', type=float, default=1e-3)
parser.add_argument('--critic-lr', type=float, default=1e-3)
parser.add_argument('--gamma', type=float, default=0.99)
parser.add_argument('--tau', type=float, default=0.005)
parser.add_argument('--alpha', type=float, default=0.2)
parser.add_argument('--auto-alpha', default=False, action='store_true')
parser.add_argument('--alpha-lr', type=float, default=3e-4)
parser.add_argument("--start-timesteps", type=int, default=10000)
parser.add_argument('--epoch', type=int, default=200)
parser.add_argument('--step-per-epoch', type=int, default=5000)
parser.add_argument('--step-per-collect', type=int, default=1)
parser.add_argument('--update-per-step', type=int, default=20)
parser.add_argument('--n-step', type=int, default=1)
parser.add_argument('--batch-size', type=int, default=256)
parser.add_argument(
'--target-mode', type=str, choices=('min', 'mean'), default='min'
)
parser.add_argument('--training-num', type=int, default=1)
parser.add_argument('--test-num', type=int, default=10)
parser.add_argument('--logdir', type=str, default='log')
parser.add_argument('--render', type=float, default=0.)
parser.add_argument(
'--device', type=str, default='cuda' if torch.cuda.is_available() else 'cpu'
)
parser.add_argument('--resume-path', type=str, default=None)
parser.add_argument(
'--watch',
default=False,
action='store_true',
help='watch the play of pre-trained policy only'
)
return parser.parse_args()
def test_redq(args=get_args()):
env = gym.make(args.task)
args.state_shape = env.observation_space.shape or env.observation_space.n
args.action_shape = env.action_space.shape or env.action_space.n
args.max_action = env.action_space.high[0]
print("Observations shape:", args.state_shape)
print("Actions shape:", args.action_shape)
print("Action range:", np.min(env.action_space.low), np.max(env.action_space.high))
# train_envs = gym.make(args.task)
if args.training_num > 1:
train_envs = SubprocVectorEnv(
[lambda: gym.make(args.task) for _ in range(args.training_num)]
)
else:
train_envs = gym.make(args.task)
# test_envs = gym.make(args.task)
test_envs = SubprocVectorEnv(
[lambda: gym.make(args.task) for _ in range(args.test_num)]
)
# seed
np.random.seed(args.seed)
torch.manual_seed(args.seed)
train_envs.seed(args.seed)
test_envs.seed(args.seed)
# model
net_a = Net(args.state_shape, hidden_sizes=args.hidden_sizes, device=args.device)
actor = ActorProb(
net_a,
args.action_shape,
max_action=args.max_action,
device=args.device,
unbounded=True,
conditioned_sigma=True
).to(args.device)
actor_optim = torch.optim.Adam(actor.parameters(), lr=args.actor_lr)
def linear(x, y):
return EnsembleLinear(args.ensemble_size, x, y)
net_c = Net(
args.state_shape,
args.action_shape,
hidden_sizes=args.hidden_sizes,
concat=True,
device=args.device,
linear_layer=linear,
)
critics = Critic(
net_c,
device=args.device,
linear_layer=linear,
flatten_input=False,
).to(args.device)
critics_optim = torch.optim.Adam(critics.parameters(), lr=args.critic_lr)
if args.auto_alpha:
target_entropy = -np.prod(env.action_space.shape)
log_alpha = torch.zeros(1, requires_grad=True, device=args.device)
alpha_optim = torch.optim.Adam([log_alpha], lr=args.alpha_lr)
args.alpha = (target_entropy, log_alpha, alpha_optim)
policy = REDQPolicy(
actor,
actor_optim,
critics,
critics_optim,
args.ensemble_size,
args.subset_size,
tau=args.tau,
gamma=args.gamma,
alpha=args.alpha,
estimation_step=args.n_step,
actor_delay=args.update_per_step,
target_mode=args.target_mode,
action_space=env.action_space,
)
# load a previous policy
if args.resume_path:
policy.load_state_dict(torch.load(args.resume_path, map_location=args.device))
print("Loaded agent from: ", args.resume_path)
# collector
if args.training_num > 1:
buffer = VectorReplayBuffer(args.buffer_size, len(train_envs))
else:
buffer = ReplayBuffer(args.buffer_size)
train_collector = Collector(policy, train_envs, buffer, exploration_noise=True)
test_collector = Collector(policy, test_envs)
train_collector.collect(n_step=args.start_timesteps, random=True)
# log
t0 = datetime.datetime.now().strftime("%m%d_%H%M%S")
log_file = f'seed_{args.seed}_{t0}-{args.task.replace("-", "_")}_redq'
log_path = os.path.join(args.logdir, args.task, 'redq', log_file)
writer = SummaryWriter(log_path)
writer.add_text("args", str(args))
logger = TensorboardLogger(writer)
def save_best_fn(policy):
torch.save(policy.state_dict(), os.path.join(log_path, 'policy.pth'))
if not args.watch:
# trainer
result = offpolicy_trainer(
policy,
train_collector,
test_collector,
args.epoch,
args.step_per_epoch,
args.step_per_collect,
args.test_num,
args.batch_size,
save_best_fn=save_best_fn,
logger=logger,
update_per_step=args.update_per_step,
test_in_train=False
)
pprint.pprint(result)
# Let's watch its performance!
policy.eval()
test_envs.seed(args.seed)
test_collector.reset()
result = test_collector.collect(n_episode=args.test_num, render=args.render)
print(f'Final reward: {result["rews"].mean()}, length: {result["lens"].mean()}')
if __name__ == '__main__':
test_redq()

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@ -0,0 +1,178 @@
import argparse
import os
import pprint
import gym
import numpy as np
import torch
from torch.utils.tensorboard import SummaryWriter
from tianshou.data import Collector, VectorReplayBuffer
from tianshou.env import DummyVectorEnv
from tianshou.policy import REDQPolicy
from tianshou.trainer import offpolicy_trainer
from tianshou.utils import TensorboardLogger
from tianshou.utils.net.common import EnsembleLinear, Net
from tianshou.utils.net.continuous import ActorProb, Critic
def get_args():
parser = argparse.ArgumentParser()
parser.add_argument('--task', type=str, default='Pendulum-v1')
parser.add_argument('--reward-threshold', type=float, default=None)
parser.add_argument('--seed', type=int, default=0)
parser.add_argument('--buffer-size', type=int, default=20000)
parser.add_argument('--ensemble-size', type=int, default=4)
parser.add_argument('--subset-size', type=int, default=2)
parser.add_argument('--actor-lr', type=float, default=1e-4)
parser.add_argument('--critic-lr', type=float, default=1e-3)
parser.add_argument('--gamma', type=float, default=0.99)
parser.add_argument('--tau', type=float, default=0.005)
parser.add_argument('--alpha', type=float, default=0.2)
parser.add_argument('--auto-alpha', action='store_true', default=False)
parser.add_argument('--alpha-lr', type=float, default=3e-4)
parser.add_argument("--start-timesteps", type=int, default=1000)
parser.add_argument('--epoch', type=int, default=5)
parser.add_argument('--step-per-epoch', type=int, default=5000)
parser.add_argument('--step-per-collect', type=int, default=1)
parser.add_argument('--update-per-step', type=int, default=3)
parser.add_argument('--n-step', type=int, default=1)
parser.add_argument('--batch-size', type=int, default=64)
parser.add_argument(
'--target-mode', type=str, choices=('min', 'mean'), default='min'
)
parser.add_argument('--hidden-sizes', type=int, nargs='*', default=[64, 64])
parser.add_argument('--training-num', type=int, default=8)
parser.add_argument('--test-num', type=int, default=100)
parser.add_argument('--logdir', type=str, default='log')
parser.add_argument('--render', type=float, default=0.)
parser.add_argument(
'--device', type=str, default='cuda' if torch.cuda.is_available() else 'cpu'
)
args = parser.parse_known_args()[0]
return args
def test_redq(args=get_args()):
env = gym.make(args.task)
args.state_shape = env.observation_space.shape or env.observation_space.n
args.action_shape = env.action_space.shape or env.action_space.n
args.max_action = env.action_space.high[0]
if args.reward_threshold is None:
default_reward_threshold = {"Pendulum-v0": -250, "Pendulum-v1": -250}
args.reward_threshold = default_reward_threshold.get(
args.task, env.spec.reward_threshold
)
# you can also use tianshou.env.SubprocVectorEnv
# train_envs = gym.make(args.task)
train_envs = DummyVectorEnv(
[lambda: gym.make(args.task) for _ in range(args.training_num)]
)
# test_envs = gym.make(args.task)
test_envs = DummyVectorEnv(
[lambda: gym.make(args.task) for _ in range(args.test_num)]
)
# seed
np.random.seed(args.seed)
torch.manual_seed(args.seed)
train_envs.seed(args.seed)
test_envs.seed(args.seed)
# model
net = Net(args.state_shape, hidden_sizes=args.hidden_sizes, device=args.device)
actor = ActorProb(
net,
args.action_shape,
max_action=args.max_action,
device=args.device,
unbounded=True,
conditioned_sigma=True
).to(args.device)
actor_optim = torch.optim.Adam(actor.parameters(), lr=args.actor_lr)
def linear(x, y):
return EnsembleLinear(args.ensemble_size, x, y)
net_c = Net(
args.state_shape,
args.action_shape,
hidden_sizes=args.hidden_sizes,
concat=True,
device=args.device,
linear_layer=linear,
)
critic = Critic(
net_c, device=args.device, linear_layer=linear, flatten_input=False
).to(args.device)
critic_optim = torch.optim.Adam(critic.parameters(), lr=args.critic_lr)
if args.auto_alpha:
target_entropy = -np.prod(env.action_space.shape)
log_alpha = torch.zeros(1, requires_grad=True, device=args.device)
alpha_optim = torch.optim.Adam([log_alpha], lr=args.alpha_lr)
args.alpha = (target_entropy, log_alpha, alpha_optim)
policy = REDQPolicy(
actor,
actor_optim,
critic,
critic_optim,
args.ensemble_size,
args.subset_size,
tau=args.tau,
gamma=args.gamma,
alpha=args.alpha,
estimation_step=args.n_step,
actor_delay=args.update_per_step,
target_mode=args.target_mode,
action_space=env.action_space,
)
# collector
train_collector = Collector(
policy,
train_envs,
VectorReplayBuffer(args.buffer_size, len(train_envs)),
exploration_noise=True
)
test_collector = Collector(policy, test_envs)
train_collector.collect(n_step=args.start_timesteps, random=True)
# log
log_path = os.path.join(args.logdir, args.task, 'redq')
writer = SummaryWriter(log_path)
logger = TensorboardLogger(writer)
def save_best_fn(policy):
torch.save(policy.state_dict(), os.path.join(log_path, 'policy.pth'))
def stop_fn(mean_rewards):
return mean_rewards >= args.reward_threshold
# trainer
result = offpolicy_trainer(
policy,
train_collector,
test_collector,
args.epoch,
args.step_per_epoch,
args.step_per_collect,
args.test_num,
args.batch_size,
update_per_step=args.update_per_step,
stop_fn=stop_fn,
save_best_fn=save_best_fn,
logger=logger
)
assert stop_fn(result['best_reward'])
if __name__ == '__main__':
pprint.pprint(result)
# Let's watch its performance!
env = gym.make(args.task)
policy.eval()
collector = Collector(policy, env)
result = collector.collect(n_episode=1, render=args.render)
rews, lens = result["rews"], result["lens"]
print(f"Final reward: {rews.mean()}, length: {lens.mean()}")
if __name__ == '__main__':
test_redq()

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@ -55,8 +55,8 @@ class PettingZooEnv(AECEnv, ABC):
self.reset()
def reset(self) -> dict:
self.env.reset()
def reset(self, *args: Any, **kwargs: Any) -> dict:
self.env.reset(*args, **kwargs)
observation = self.env.observe(self.env.agent_selection)
if isinstance(observation, dict) and 'action_mask' in observation:
return {
@ -103,7 +103,10 @@ class PettingZooEnv(AECEnv, ABC):
self.env.close()
def seed(self, seed: Any = None) -> None:
self.env.seed(seed)
try:
self.env.seed(seed)
except NotImplementedError:
self.env.reset(seed=seed)
def render(self, mode: str = "human") -> Any:
return self.env.render(mode)

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@ -17,6 +17,7 @@ from tianshou.policy.modelfree.ppo import PPOPolicy
from tianshou.policy.modelfree.trpo import TRPOPolicy
from tianshou.policy.modelfree.td3 import TD3Policy
from tianshou.policy.modelfree.sac import SACPolicy
from tianshou.policy.modelfree.redq import REDQPolicy
from tianshou.policy.modelfree.discrete_sac import DiscreteSACPolicy
from tianshou.policy.imitation.base import ImitationPolicy
from tianshou.policy.imitation.bcq import BCQPolicy
@ -46,6 +47,7 @@ __all__ = [
"TRPOPolicy",
"TD3Policy",
"SACPolicy",
"REDQPolicy",
"DiscreteSACPolicy",
"ImitationPolicy",
"BCQPolicy",

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@ -0,0 +1,200 @@
from copy import deepcopy
from typing import Any, Dict, Optional, Tuple, Union
import numpy as np
import torch
from torch.distributions import Independent, Normal
from tianshou.data import Batch, ReplayBuffer
from tianshou.exploration import BaseNoise
from tianshou.policy import DDPGPolicy
class REDQPolicy(DDPGPolicy):
"""Implementation of REDQ. arXiv:2101.05982.
:param torch.nn.Module actor: the actor network following the rules in
:class:`~tianshou.policy.BasePolicy`. (s -> logits)
:param torch.optim.Optimizer actor_optim: the optimizer for actor network.
:param torch.nn.Module critics: critic ensemble networks.
:param torch.optim.Optimizer critics_optim: the optimizer for the critic networks.
:param int ensemble_size: Number of sub-networks in the critic ensemble.
Default to 10.
:param int subset_size: Number of networks in the subset. Default to 2.
:param float tau: param for soft update of the target network. Default to 0.005.
:param float gamma: discount factor, in [0, 1]. Default to 0.99.
:param (float, torch.Tensor, torch.optim.Optimizer) or float alpha: entropy
regularization coefficient. Default to 0.2.
If a tuple (target_entropy, log_alpha, alpha_optim) is provided, then
alpha is automatically tuned.
:param bool reward_normalization: normalize the reward to Normal(0, 1).
Default to False.
:param int actor_delay: Number of critic updates before an actor update.
Default to 20.
:param BaseNoise exploration_noise: add a noise to action for exploration.
Default to None. This is useful when solving hard-exploration problem.
:param bool deterministic_eval: whether to use deterministic action (mean
of Gaussian policy) instead of stochastic action sampled by the policy.
Default to True.
:param str target_mode: methods to integrate critic values in the subset,
currently support minimum and average. Default to min.
:param bool action_scaling: whether to map actions from range [-1, 1] to range
[action_spaces.low, action_spaces.high]. Default to True.
:param str action_bound_method: method to bound action to range [-1, 1], can be
either "clip" (for simply clipping the action) or empty string for no bounding.
Default to "clip".
:param Optional[gym.Space] action_space: env's action space, mandatory if you want
to use option "action_scaling" or "action_bound_method". Default to None.
.. seealso::
Please refer to :class:`~tianshou.policy.BasePolicy` for more detailed
explanation.
"""
def __init__(
self,
actor: torch.nn.Module,
actor_optim: torch.optim.Optimizer,
critics: torch.nn.Module,
critics_optim: torch.optim.Optimizer,
ensemble_size: int = 10,
subset_size: int = 2,
tau: float = 0.005,
gamma: float = 0.99,
alpha: Union[float, Tuple[float, torch.Tensor, torch.optim.Optimizer]] = 0.2,
reward_normalization: bool = False,
estimation_step: int = 1,
actor_delay: int = 20,
exploration_noise: Optional[BaseNoise] = None,
deterministic_eval: bool = True,
target_mode: str = "min",
**kwargs: Any,
) -> None:
super().__init__(
None, None, None, None, tau, gamma, exploration_noise,
reward_normalization, estimation_step, **kwargs
)
self.actor, self.actor_optim = actor, actor_optim
self.critics, self.critics_old = critics, deepcopy(critics)
self.critics_old.eval()
self.critics_optim = critics_optim
assert 0 < subset_size <= ensemble_size, \
"Invalid choice of ensemble size or subset size."
self.ensemble_size = ensemble_size
self.subset_size = subset_size
self._is_auto_alpha = False
self._alpha: Union[float, torch.Tensor]
if isinstance(alpha, tuple):
self._is_auto_alpha = True
self._target_entropy, self._log_alpha, self._alpha_optim = alpha
assert alpha[1].shape == torch.Size([1]) and alpha[1].requires_grad
self._alpha = self._log_alpha.detach().exp()
else:
self._alpha = alpha
if target_mode in ("min", "mean"):
self.target_mode = target_mode
else:
raise ValueError("Unsupported mode of Q target computing.")
self.critic_gradient_step = 0
self.actor_delay = actor_delay
self._deterministic_eval = deterministic_eval
self.__eps = np.finfo(np.float32).eps.item()
def train(self, mode: bool = True) -> "REDQPolicy":
self.training = mode
self.actor.train(mode)
self.critics.train(mode)
return self
def sync_weight(self) -> None:
for o, n in zip(self.critics_old.parameters(), self.critics.parameters()):
o.data.copy_(o.data * (1.0 - self.tau) + n.data * self.tau)
def forward( # type: ignore
self,
batch: Batch,
state: Optional[Union[dict, Batch, np.ndarray]] = None,
input: str = "obs",
**kwargs: Any,
) -> Batch:
obs = batch[input]
logits, h = self.actor(obs, state=state, info=batch.info)
assert isinstance(logits, tuple)
dist = Independent(Normal(*logits), 1)
if self._deterministic_eval and not self.training:
act = logits[0]
else:
act = dist.rsample()
log_prob = dist.log_prob(act).unsqueeze(-1)
# apply correction for Tanh squashing when computing logprob from Gaussian
# You can check out the original SAC paper (arXiv 1801.01290): Eq 21.
# in appendix C to get some understanding of this equation.
squashed_action = torch.tanh(act)
log_prob = log_prob - torch.log((1 - squashed_action.pow(2)) +
self.__eps).sum(-1, keepdim=True)
return Batch(
logits=logits, act=squashed_action, state=h, dist=dist, log_prob=log_prob
)
def _target_q(self, buffer: ReplayBuffer, indices: np.ndarray) -> torch.Tensor:
batch = buffer[indices] # batch.obs: s_{t+n}
obs_next_result = self(batch, input="obs_next")
a_ = obs_next_result.act
sample_ensemble_idx = np.random.choice(
self.ensemble_size, self.subset_size, replace=False
)
qs = self.critics_old(batch.obs_next, a_)[sample_ensemble_idx, ...]
if self.target_mode == "min":
target_q, _ = torch.min(qs, dim=0)
elif self.target_mode == "mean":
target_q = torch.mean(qs, dim=0)
target_q -= self._alpha * obs_next_result.log_prob
return target_q
def learn(self, batch: Batch, **kwargs: Any) -> Dict[str, float]:
# critic ensemble
weight = getattr(batch, "weight", 1.0)
current_qs = self.critics(batch.obs, batch.act).flatten(1)
target_q = batch.returns.flatten()
td = current_qs - target_q
critic_loss = (td.pow(2) * weight).mean()
self.critics_optim.zero_grad()
critic_loss.backward()
self.critics_optim.step()
batch.weight = torch.mean(td, dim=0) # prio-buffer
self.critic_gradient_step += 1
# actor
if self.critic_gradient_step % self.actor_delay == 0:
obs_result = self(batch)
a = obs_result.act
current_qa = self.critics(batch.obs, a).mean(dim=0).flatten()
actor_loss = (self._alpha * obs_result.log_prob.flatten() -
current_qa).mean()
self.actor_optim.zero_grad()
actor_loss.backward()
self.actor_optim.step()
if self._is_auto_alpha:
log_prob = obs_result.log_prob.detach() + self._target_entropy
alpha_loss = -(self._log_alpha * log_prob).mean()
self._alpha_optim.zero_grad()
alpha_loss.backward()
self._alpha_optim.step()
self._alpha = self._log_alpha.detach().exp()
self.sync_weight()
result = {"loss/critics": critic_loss.item()}
if self.critic_gradient_step % self.actor_delay == 0:
result["loss/actor"] = actor_loss.item(),
if self._is_auto_alpha:
result["loss/alpha"] = alpha_loss.item()
result["alpha"] = self._alpha.item() # type: ignore
return result

View File

@ -1,4 +1,14 @@
from typing import Any, Dict, List, Optional, Sequence, Tuple, Type, Union
from typing import (
Any,
Dict,
List,
Optional,
Sequence,
Tuple,
Type,
Union,
no_type_check,
)
import numpy as np
import torch
@ -46,6 +56,7 @@ class MLP(nn.Module):
nn.ReLU.
:param device: which device to create this model on. Default to None.
:param linear_layer: use this module as linear layer. Default to nn.Linear.
:param bool flatten_input: whether to flatten input data. Default to True.
"""
def __init__(
@ -57,6 +68,7 @@ class MLP(nn.Module):
activation: Optional[Union[ModuleType, Sequence[ModuleType]]] = nn.ReLU,
device: Optional[Union[str, int, torch.device]] = None,
linear_layer: Type[nn.Linear] = nn.Linear,
flatten_input: bool = True,
) -> None:
super().__init__()
self.device = device
@ -86,15 +98,15 @@ class MLP(nn.Module):
model += [linear_layer(hidden_sizes[-1], output_dim)]
self.output_dim = output_dim or hidden_sizes[-1]
self.model = nn.Sequential(*model)
self.flatten_input = flatten_input
@no_type_check
def forward(self, obs: Union[np.ndarray, torch.Tensor]) -> torch.Tensor:
if self.device is not None:
obs = torch.as_tensor(
obs,
device=self.device, # type: ignore
dtype=torch.float32,
)
return self.model(obs.flatten(1)) # type: ignore
obs = torch.as_tensor(obs, device=self.device, dtype=torch.float32)
if self.flatten_input:
obs = obs.flatten(1)
return self.model(obs)
class Net(nn.Module):
@ -129,6 +141,7 @@ class Net(nn.Module):
pass a tuple of two dict (first for Q and second for V) stating
self-defined arguments as stated in
class:`~tianshou.utils.net.common.MLP`. Default to None.
:param linear_layer: use this module as linear layer. Default to nn.Linear.
.. seealso::
@ -152,6 +165,7 @@ class Net(nn.Module):
concat: bool = False,
num_atoms: int = 1,
dueling_param: Optional[Tuple[Dict[str, Any], Dict[str, Any]]] = None,
linear_layer: Type[nn.Linear] = nn.Linear,
) -> None:
super().__init__()
self.device = device
@ -164,7 +178,8 @@ class Net(nn.Module):
self.use_dueling = dueling_param is not None
output_dim = action_dim if not self.use_dueling and not concat else 0
self.model = MLP(
input_dim, output_dim, hidden_sizes, norm_layer, activation, device
input_dim, output_dim, hidden_sizes, norm_layer, activation, device,
linear_layer
)
self.output_dim = self.model.output_dim
if self.use_dueling: # dueling DQN
@ -311,3 +326,40 @@ class DataParallelNet(nn.Module):
if not isinstance(obs, torch.Tensor):
obs = torch.as_tensor(obs, dtype=torch.float32)
return self.net(obs=obs.cuda(), *args, **kwargs)
class EnsembleLinear(nn.Module):
"""Linear Layer of Ensemble network.
:param int ensemble_size: Number of subnets in the ensemble.
:param int inp_feature: dimension of the input vector.
:param int out_feature: dimension of the output vector.
:param bool bias: whether to include an additive bias, default to be True.
"""
def __init__(
self,
ensemble_size: int,
in_feature: int,
out_feature: int,
bias: bool = True,
) -> None:
super().__init__()
# To be consistent with PyTorch default initializer
k = np.sqrt(1. / in_feature)
weight_data = torch.rand((ensemble_size, in_feature, out_feature)) * 2 * k - k
self.weight = nn.Parameter(weight_data, requires_grad=True)
self.bias: Union[nn.Parameter, None]
if bias:
bias_data = torch.rand((ensemble_size, 1, out_feature)) * 2 * k - k
self.bias = nn.Parameter(bias_data, requires_grad=True)
else:
self.bias = None
def forward(self, x: torch.Tensor) -> torch.Tensor:
x = torch.matmul(x, self.weight)
if self.bias is not None:
x = x + self.bias
return x

View File

@ -1,4 +1,4 @@
from typing import Any, Dict, Optional, Sequence, Tuple, Union
from typing import Any, Dict, Optional, Sequence, Tuple, Type, Union
import numpy as np
import torch
@ -79,6 +79,9 @@ class Critic(nn.Module):
only a single linear layer).
:param int preprocess_net_output_dim: the output dimension of
preprocess_net.
:param linear_layer: use this module as linear layer. Default to nn.Linear.
:param bool flatten_input: whether to flatten input data for the last layer.
Default to True.
For advanced usage (how to customize the network), please refer to
:ref:`build_the_network`.
@ -95,6 +98,8 @@ class Critic(nn.Module):
hidden_sizes: Sequence[int] = (),
device: Union[str, int, torch.device] = "cpu",
preprocess_net_output_dim: Optional[int] = None,
linear_layer: Type[nn.Linear] = nn.Linear,
flatten_input: bool = True,
) -> None:
super().__init__()
self.device = device
@ -105,7 +110,9 @@ class Critic(nn.Module):
input_dim, # type: ignore
1,
hidden_sizes,
device=self.device
device=self.device,
linear_layer=linear_layer,
flatten_input=flatten_input,
)
def forward(