Tianshou/examples/atari/atari_network.py
wizardsheng 1eb6137645
Add QR-DQN algorithm (#276)
This is the PR for QR-DQN algorithm: https://arxiv.org/abs/1710.10044

1. add QR-DQN policy in tianshou/policy/modelfree/qrdqn.py.
2. add QR-DQN net in examples/atari/atari_network.py.
3. add QR-DQN atari example in examples/atari/atari_qrdqn.py.
4. add QR-DQN statement in tianshou/policy/init.py.
5. add QR-DQN unit test in test/discrete/test_qrdqn.py.
6. add QR-DQN atari results in examples/atari/results/qrdqn/.
7. add compute_q_value in DQNPolicy and C51Policy for simplify forward function.
8. move `with torch.no_grad():` from `_target_q` to BasePolicy

By running "python3 atari_qrdqn.py --task "PongNoFrameskip-v4" --batch-size 64", get best_result': '19.8 ± 0.40', in epoch 8.
2021-01-28 09:27:05 +08:00

115 lines
3.5 KiB
Python

import torch
import numpy as np
from torch import nn
from typing import Any, Dict, Tuple, Union, Optional, Sequence
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: Union[str, int, torch.device] = "cpu",
features_only: bool = False,
) -> None:
super().__init__()
self.device = device
self.net = nn.Sequential(
nn.Conv2d(c, 32, kernel_size=8, stride=4), nn.ReLU(inplace=True),
nn.Conv2d(32, 64, kernel_size=4, stride=2), nn.ReLU(inplace=True),
nn.Conv2d(64, 64, kernel_size=3, stride=1), nn.ReLU(inplace=True),
nn.Flatten())
with torch.no_grad():
self.output_dim = np.prod(
self.net(torch.zeros(1, c, h, w)).shape[1:])
if not features_only:
self.net = nn.Sequential(
self.net,
nn.Linear(self.output_dim, 512), nn.ReLU(inplace=True),
nn.Linear(512, np.prod(action_shape)))
self.output_dim = np.prod(action_shape)
def forward(
self,
x: Union[np.ndarray, torch.Tensor],
state: Optional[Any] = None,
info: Dict[str, Any] = {},
) -> Tuple[torch.Tensor, Any]:
r"""Mapping: x -> Q(x, \*)."""
x = torch.as_tensor(x, device=self.device, dtype=torch.float32)
return self.net(x), 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: Union[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,
x: Union[np.ndarray, torch.Tensor],
state: Optional[Any] = None,
info: Dict[str, Any] = {},
) -> Tuple[torch.Tensor, Any]:
r"""Mapping: x -> Z(x, \*)."""
x, state = super().forward(x)
x = x.view(-1, self.num_atoms).softmax(dim=-1)
x = x.view(-1, self.action_num, self.num_atoms)
return x, 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: Union[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,
x: Union[np.ndarray, torch.Tensor],
state: Optional[Any] = None,
info: Dict[str, Any] = {},
) -> Tuple[torch.Tensor, Any]:
r"""Mapping: x -> Z(x, \*)."""
x, state = super().forward(x)
x = x.view(-1, self.action_num, self.num_quantiles)
return x, state