Tianshou/examples/atari/atari_network.py
2023-10-18 20:44:18 +02:00

272 lines
8.5 KiB
Python

from collections.abc import Callable, Sequence
from typing import Any
import numpy as np
import torch
from torch import nn
from tianshou.highlevel.env import Environments
from tianshou.highlevel.module.actor import ActorFactory
from tianshou.highlevel.module.core import (
TDevice,
)
from tianshou.highlevel.module.intermediate import (
IntermediateModule,
IntermediateModuleFactory,
)
from tianshou.utils.net.discrete import Actor, NoisyLinear
def layer_init(layer: nn.Module, std: float = np.sqrt(2), bias_const: float = 0.0) -> nn.Module:
torch.nn.init.orthogonal_(layer.weight, std)
torch.nn.init.constant_(layer.bias, bias_const)
return layer
def scale_obs(module: type[nn.Module], denom: float = 255.0) -> type[nn.Module]:
class scaled_module(module):
def forward(
self,
obs: np.ndarray | torch.Tensor,
state: Any | None = None,
info: dict[str, Any] | None = None,
) -> tuple[torch.Tensor, Any]:
if info is None:
info = {}
return super().forward(obs / denom, state, info)
return scaled_module
class DQN(nn.Module):
"""Reference: Human-level control through deep reinforcement learning.
For advanced usage (how to customize the network), please refer to
:ref:`build_the_network`.
"""
def __init__(
self,
c: int,
h: int,
w: int,
action_shape: Sequence[int],
device: str | int | torch.device = "cpu",
features_only: bool = False,
output_dim: int | None = None,
layer_init: Callable[[nn.Module], nn.Module] = lambda x: x,
) -> None:
super().__init__()
self.device = device
self.net = nn.Sequential(
layer_init(nn.Conv2d(c, 32, kernel_size=8, stride=4)),
nn.ReLU(inplace=True),
layer_init(nn.Conv2d(32, 64, kernel_size=4, stride=2)),
nn.ReLU(inplace=True),
layer_init(nn.Conv2d(64, 64, kernel_size=3, stride=1)),
nn.ReLU(inplace=True),
nn.Flatten(),
)
with torch.no_grad():
self.output_dim = int(np.prod(self.net(torch.zeros(1, c, h, w)).shape[1:]))
if not features_only:
self.net = nn.Sequential(
self.net,
layer_init(nn.Linear(self.output_dim, 512)),
nn.ReLU(inplace=True),
layer_init(nn.Linear(512, int(np.prod(action_shape)))),
)
self.output_dim = np.prod(action_shape)
elif output_dim is not None:
self.net = nn.Sequential(
self.net,
layer_init(nn.Linear(self.output_dim, output_dim)),
nn.ReLU(inplace=True),
)
self.output_dim = output_dim
def forward(
self,
obs: np.ndarray | torch.Tensor,
state: Any | None = None,
info: dict[str, Any] | None = None,
) -> tuple[torch.Tensor, Any]:
r"""Mapping: s -> Q(s, \*)."""
if info is None:
info = {}
obs = torch.as_tensor(obs, device=self.device, dtype=torch.float32)
return self.net(obs), state
class C51(DQN):
"""Reference: A distributional perspective on reinforcement learning.
For advanced usage (how to customize the network), please refer to
:ref:`build_the_network`.
"""
def __init__(
self,
c: int,
h: int,
w: int,
action_shape: Sequence[int],
num_atoms: int = 51,
device: str | int | torch.device = "cpu",
) -> None:
self.action_num = np.prod(action_shape)
super().__init__(c, h, w, [self.action_num * num_atoms], device)
self.num_atoms = num_atoms
def forward(
self,
obs: np.ndarray | torch.Tensor,
state: Any | None = None,
info: dict[str, Any] | None = None,
) -> tuple[torch.Tensor, Any]:
r"""Mapping: x -> Z(x, \*)."""
if info is None:
info = {}
obs, state = super().forward(obs)
obs = obs.view(-1, self.num_atoms).softmax(dim=-1)
obs = obs.view(-1, self.action_num, self.num_atoms)
return obs, state
class Rainbow(DQN):
"""Reference: Rainbow: Combining Improvements in Deep Reinforcement Learning.
For advanced usage (how to customize the network), please refer to
:ref:`build_the_network`.
"""
def __init__(
self,
c: int,
h: int,
w: int,
action_shape: Sequence[int],
num_atoms: int = 51,
noisy_std: float = 0.5,
device: str | int | torch.device = "cpu",
is_dueling: bool = True,
is_noisy: bool = True,
) -> None:
super().__init__(c, h, w, action_shape, device, features_only=True)
self.action_num = np.prod(action_shape)
self.num_atoms = num_atoms
def linear(x, y):
if is_noisy:
return NoisyLinear(x, y, noisy_std)
return nn.Linear(x, y)
self.Q = nn.Sequential(
linear(self.output_dim, 512),
nn.ReLU(inplace=True),
linear(512, self.action_num * self.num_atoms),
)
self._is_dueling = is_dueling
if self._is_dueling:
self.V = nn.Sequential(
linear(self.output_dim, 512),
nn.ReLU(inplace=True),
linear(512, self.num_atoms),
)
self.output_dim = self.action_num * self.num_atoms
def forward(
self,
obs: np.ndarray | torch.Tensor,
state: Any | None = None,
info: dict[str, Any] | None = None,
) -> tuple[torch.Tensor, Any]:
r"""Mapping: x -> Z(x, \*)."""
if info is None:
info = {}
obs, state = super().forward(obs)
q = self.Q(obs)
q = q.view(-1, self.action_num, self.num_atoms)
if self._is_dueling:
v = self.V(obs)
v = v.view(-1, 1, self.num_atoms)
logits = q - q.mean(dim=1, keepdim=True) + v
else:
logits = q
probs = logits.softmax(dim=2)
return probs, state
class QRDQN(DQN):
"""Reference: Distributional Reinforcement Learning with Quantile Regression.
For advanced usage (how to customize the network), please refer to
:ref:`build_the_network`.
"""
def __init__(
self,
c: int,
h: int,
w: int,
action_shape: Sequence[int],
num_quantiles: int = 200,
device: str | int | torch.device = "cpu",
) -> None:
self.action_num = np.prod(action_shape)
super().__init__(c, h, w, [self.action_num * num_quantiles], device)
self.num_quantiles = num_quantiles
def forward(
self,
obs: np.ndarray | torch.Tensor,
state: Any | None = None,
info: dict[str, Any] | None = None,
) -> tuple[torch.Tensor, Any]:
r"""Mapping: x -> Z(x, \*)."""
if info is None:
info = {}
obs, state = super().forward(obs)
obs = obs.view(-1, self.action_num, self.num_quantiles)
return obs, state
class ActorFactoryAtariDQN(ActorFactory):
def __init__(self, hidden_size: int | Sequence[int], scale_obs: bool, features_only: bool):
self.hidden_size = hidden_size
self.scale_obs = scale_obs
self.features_only = features_only
def create_module(self, envs: Environments, device: TDevice) -> Actor:
net_cls = scale_obs(DQN) if self.scale_obs else DQN
net = net_cls(
*envs.get_observation_shape(),
envs.get_action_shape(),
device=device,
features_only=self.features_only,
output_dim=self.hidden_size,
layer_init=layer_init,
)
return Actor(net, envs.get_action_shape(), device=device, softmax_output=False).to(device)
class IntermediateModuleFactoryAtariDQN(IntermediateModuleFactory):
def __init__(self, features_only: bool = False, net_only: bool = False):
self.features_only = features_only
self.net_only = net_only
def create_intermediate_module(self, envs: Environments, device: TDevice) -> IntermediateModule:
dqn = DQN(
*envs.get_observation_shape(),
envs.get_action_shape(),
device=device,
features_only=self.features_only,
).to(device)
module = dqn.net if self.net_only else dqn
return IntermediateModule(module, dqn.output_dim)
class IntermediateModuleFactoryAtariDQNFeatures(IntermediateModuleFactoryAtariDQN):
def __init__(self):
super().__init__(features_only=True, net_only=True)