Spaces:
Build error
Build error
File size: 8,564 Bytes
f238a34 |
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 |
from typing import Any, Dict, List, Optional, Type
import gym
import torch as th
from torch import nn
from stable_baselines3.common.policies import BasePolicy, register_policy
from stable_baselines3.common.torch_layers import BaseFeaturesExtractor, FlattenExtractor, NatureCNN, create_mlp
from stable_baselines3.common.type_aliases import Schedule
class QNetwork(BasePolicy):
"""
Action-Value (Q-Value) network for DQN
:param observation_space: Observation space
:param action_space: Action space
:param net_arch: The specification of the policy and value networks.
:param activation_fn: Activation function
:param normalize_images: Whether to normalize images or not,
dividing by 255.0 (True by default)
"""
def __init__(
self,
observation_space: gym.spaces.Space,
action_space: gym.spaces.Space,
features_extractor: nn.Module,
features_dim: int,
net_arch: Optional[List[int]] = None,
activation_fn: Type[nn.Module] = nn.ReLU,
normalize_images: bool = True,
):
super(QNetwork, self).__init__(
observation_space,
action_space,
features_extractor=features_extractor,
normalize_images=normalize_images,
)
if net_arch is None:
net_arch = [64, 64]
self.net_arch = net_arch
self.activation_fn = activation_fn
self.features_extractor = features_extractor
self.features_dim = features_dim
self.normalize_images = normalize_images
action_dim = self.action_space.n # number of actions
q_net = create_mlp(self.features_dim, action_dim, self.net_arch, self.activation_fn)
self.q_net = nn.Sequential(*q_net)
def forward(self, obs: th.Tensor) -> th.Tensor:
"""
Predict the q-values.
:param obs: Observation
:return: The estimated Q-Value for each action.
"""
return self.q_net(self.extract_features(obs))
def _predict(self, observation: th.Tensor, deterministic: bool = True) -> th.Tensor:
q_values = self.forward(observation)
# Greedy action
action = q_values.argmax(dim=1).reshape(-1)
return action
def _get_constructor_parameters(self) -> Dict[str, Any]:
data = super()._get_constructor_parameters()
data.update(
dict(
net_arch=self.net_arch,
features_dim=self.features_dim,
activation_fn=self.activation_fn,
features_extractor=self.features_extractor,
)
)
return data
class DQNPolicy(BasePolicy):
"""
Policy class with Q-Value Net and target net for DQN
:param observation_space: Observation space
:param action_space: Action space
:param lr_schedule: Learning rate schedule (could be constant)
:param net_arch: The specification of the policy and value networks.
:param activation_fn: Activation function
:param features_extractor_class: Features extractor to use.
:param features_extractor_kwargs: Keyword arguments
to pass to the features extractor.
:param normalize_images: Whether to normalize images or not,
dividing by 255.0 (True by default)
:param optimizer_class: The optimizer to use,
``th.optim.Adam`` by default
:param optimizer_kwargs: Additional keyword arguments,
excluding the learning rate, to pass to the optimizer
"""
def __init__(
self,
observation_space: gym.spaces.Space,
action_space: gym.spaces.Space,
lr_schedule: Schedule,
net_arch: Optional[List[int]] = None,
activation_fn: Type[nn.Module] = nn.ReLU,
features_extractor_class: Type[BaseFeaturesExtractor] = FlattenExtractor,
features_extractor_kwargs: Optional[Dict[str, Any]] = None,
normalize_images: bool = True,
optimizer_class: Type[th.optim.Optimizer] = th.optim.Adam,
optimizer_kwargs: Optional[Dict[str, Any]] = None,
):
super(DQNPolicy, self).__init__(
observation_space,
action_space,
features_extractor_class,
features_extractor_kwargs,
optimizer_class=optimizer_class,
optimizer_kwargs=optimizer_kwargs,
)
if net_arch is None:
if features_extractor_class == FlattenExtractor:
net_arch = [64, 64]
else:
net_arch = []
self.net_arch = net_arch
self.activation_fn = activation_fn
self.normalize_images = normalize_images
self.net_args = {
"observation_space": self.observation_space,
"action_space": self.action_space,
"net_arch": self.net_arch,
"activation_fn": self.activation_fn,
"normalize_images": normalize_images,
}
self.q_net, self.q_net_target = None, None
self._build(lr_schedule)
def _build(self, lr_schedule: Schedule) -> None:
"""
Create the network and the optimizer.
:param lr_schedule: Learning rate schedule
lr_schedule(1) is the initial learning rate
"""
self.q_net = self.make_q_net()
self.q_net_target = self.make_q_net()
self.q_net_target.load_state_dict(self.q_net.state_dict())
# Setup optimizer with initial learning rate
self.optimizer = self.optimizer_class(self.parameters(), lr=lr_schedule(1), **self.optimizer_kwargs)
def make_q_net(self) -> QNetwork:
# Make sure we always have separate networks for features extractors etc
net_args = self._update_features_extractor(self.net_args, features_extractor=None)
return QNetwork(**net_args).to(self.device)
def forward(self, obs: th.Tensor, deterministic: bool = True) -> th.Tensor:
return self._predict(obs, deterministic=deterministic)
def _predict(self, obs: th.Tensor, deterministic: bool = True) -> th.Tensor:
return self.q_net._predict(obs, deterministic=deterministic)
def _get_constructor_parameters(self) -> Dict[str, Any]:
data = super()._get_constructor_parameters()
data.update(
dict(
net_arch=self.net_args["net_arch"],
activation_fn=self.net_args["activation_fn"],
lr_schedule=self._dummy_schedule, # dummy lr schedule, not needed for loading policy alone
optimizer_class=self.optimizer_class,
optimizer_kwargs=self.optimizer_kwargs,
features_extractor_class=self.features_extractor_class,
features_extractor_kwargs=self.features_extractor_kwargs,
)
)
return data
MlpPolicy = DQNPolicy
class CnnPolicy(DQNPolicy):
"""
Policy class for DQN when using images as input.
:param observation_space: Observation space
:param action_space: Action space
:param lr_schedule: Learning rate schedule (could be constant)
:param net_arch: The specification of the policy and value networks.
:param activation_fn: Activation function
:param features_extractor_class: Features extractor to use.
:param normalize_images: Whether to normalize images or not,
dividing by 255.0 (True by default)
:param optimizer_class: The optimizer to use,
``th.optim.Adam`` by default
:param optimizer_kwargs: Additional keyword arguments,
excluding the learning rate, to pass to the optimizer
"""
def __init__(
self,
observation_space: gym.spaces.Space,
action_space: gym.spaces.Space,
lr_schedule: Schedule,
net_arch: Optional[List[int]] = None,
activation_fn: Type[nn.Module] = nn.ReLU,
features_extractor_class: Type[BaseFeaturesExtractor] = NatureCNN,
features_extractor_kwargs: Optional[Dict[str, Any]] = None,
normalize_images: bool = True,
optimizer_class: Type[th.optim.Optimizer] = th.optim.Adam,
optimizer_kwargs: Optional[Dict[str, Any]] = None,
):
super(CnnPolicy, self).__init__(
observation_space,
action_space,
lr_schedule,
net_arch,
activation_fn,
features_extractor_class,
features_extractor_kwargs,
normalize_images,
optimizer_class,
optimizer_kwargs,
)
register_policy("MlpPolicy", MlpPolicy)
register_policy("CnnPolicy", CnnPolicy)
|