Merged in fix/flake8 (pull request #8)

Fixes all the flake8 complaints

Approved-by: Nikita Rudin

README.md

@@ -21,4 +21,4 @@ black --line-length 120 .
 # for checking lints
 pip install flake8
 flake8 .
-```
+```

rsl_rl/__init__.py

@@ -1,2 +1,2 @@
 #  Copyright 2021 ETH Zurich, NVIDIA CORPORATION
-#  SPDX-License-Identifier: BSD-3-Clause
+#  SPDX-License-Identifier: BSD-3-Clause

rsl_rl/algorithms/__init__.py

@@ -1,4 +1,8 @@
 #  Copyright 2021 ETH Zurich, NVIDIA CORPORATION
 #  SPDX-License-Identifier: BSD-3-Clause
 
-from .ppo import PPO
+"""Implementation of different RL agents."""
+
+from .ppo import PPO
+
+__all__ = ["PPO"]

rsl_rl/algorithms/ppo.py

@@ -1,40 +1,36 @@
 #  Copyright 2021 ETH Zurich, NVIDIA CORPORATION
 #  SPDX-License-Identifier: BSD-3-Clause
 
-from datetime import datetime
-import os
-import time
-
-from gym.spaces import Space
-import statistics
-from collections import deque
-
+# torch
 import torch
 import torch.nn as nn
 import torch.optim as optim
-from torch.utils.tensorboard import SummaryWriter
 
+# rsl-rl
 from rsl_rl.modules import ActorCritic
 from rsl_rl.storage import RolloutStorage
 
+
 class PPO:
     actor_critic: ActorCritic
-    def __init__(self,
-                 actor_critic,
-                 num_learning_epochs=1,
-                 num_mini_batches=1,
-                 clip_param=0.2,
-                 gamma=0.998,
-                 lam=0.95,
-                 value_loss_coef=1.0,
-                 entropy_coef=0.0,
-                 learning_rate=1e-3,
-                 max_grad_norm=1.0,
-                 use_clipped_value_loss=True,
-                 schedule="fixed",
-                 desired_kl=0.01,
-                 device='cpu',
-                 ):
+
+    def __init__(
+        self,
+        actor_critic,
+        num_learning_epochs=1,
+        num_mini_batches=1,
+        clip_param=0.2,
+        gamma=0.998,
+        lam=0.95,
+        value_loss_coef=1.0,
+        entropy_coef=0.0,
+        learning_rate=1e-3,
+        max_grad_norm=1.0,
+        use_clipped_value_loss=True,
+        schedule="fixed",
+        desired_kl=0.01,
+        device="cpu",
+    ):
 
         self.device = device
 
@@ -45,7 +41,7 @@ def __init__(self,
         # PPO components
         self.actor_critic = actor_critic
         self.actor_critic.to(self.device)
-        self.storage = None # initialized later
+        self.storage = None  # initialized later
         self.optimizer = optim.Adam(self.actor_critic.parameters(), lr=learning_rate)
         self.transition = RolloutStorage.Transition()
 
@@ -61,11 +57,13 @@ def __init__(self,
         self.use_clipped_value_loss = use_clipped_value_loss
 
     def init_storage(self, num_envs, num_transitions_per_env, actor_obs_shape, critic_obs_shape, action_shape):
-        self.storage = RolloutStorage(num_envs, num_transitions_per_env, actor_obs_shape, critic_obs_shape, action_shape, self.device)
+        self.storage = RolloutStorage(
+            num_envs, num_transitions_per_env, actor_obs_shape, critic_obs_shape, action_shape, self.device
+        )
 
     def test_mode(self):
         self.actor_critic.test()
-    
+
     def train_mode(self):
         self.actor_critic.train()
 
@@ -82,21 +80,23 @@ def act(self, obs, critic_obs):
         self.transition.observations = obs
         self.transition.critic_observations = critic_obs
         return self.transition.actions
-    
+
     def process_env_step(self, rewards, dones, infos):
         self.transition.rewards = rewards.clone()
         self.transition.dones = dones
         # Bootstrapping on time outs
-        if 'time_outs' in infos:
-            self.transition.rewards += self.gamma * torch.squeeze(self.transition.values * infos['time_outs'].unsqueeze(1).to(self.device), 1)
+        if "time_outs" in infos:
+            self.transition.rewards += self.gamma * torch.squeeze(
+                self.transition.values * infos["time_outs"].unsqueeze(1).to(self.device), 1
+            )
 
         # Record the transition
         self.storage.add_transitions(self.transition)
         self.transition.clear()
         self.actor_critic.reset(dones)
-    
+
     def compute_returns(self, last_critic_obs):
-        last_values= self.actor_critic.evaluate(last_critic_obs).detach()
+        last_values = self.actor_critic.evaluate(last_critic_obs).detach()
         self.storage.compute_returns(last_values, self.gamma, self.lam)
 
     def update(self):
@@ -106,60 +106,78 @@ def update(self):
             generator = self.storage.reccurent_mini_batch_generator(self.num_mini_batches, self.num_learning_epochs)
         else:
             generator = self.storage.mini_batch_generator(self.num_mini_batches, self.num_learning_epochs)
-        for obs_batch, critic_obs_batch, actions_batch, target_values_batch, advantages_batch, returns_batch, old_actions_log_prob_batch, \
-            old_mu_batch, old_sigma_batch, hid_states_batch, masks_batch in generator:
-
-
-                self.actor_critic.act(obs_batch, masks=masks_batch, hidden_states=hid_states_batch[0])
-                actions_log_prob_batch = self.actor_critic.get_actions_log_prob(actions_batch)
-                value_batch = self.actor_critic.evaluate(critic_obs_batch, masks=masks_batch, hidden_states=hid_states_batch[1])
-                mu_batch = self.actor_critic.action_mean
-                sigma_batch = self.actor_critic.action_std
-                entropy_batch = self.actor_critic.entropy
-
-                # KL
-                if self.desired_kl != None and self.schedule == 'adaptive':
-                    with torch.inference_mode():
-                        kl = torch.sum(
-                            torch.log(sigma_batch / old_sigma_batch + 1.e-5) + (torch.square(old_sigma_batch) + torch.square(old_mu_batch - mu_batch)) / (2.0 * torch.square(sigma_batch)) - 0.5, axis=-1)
-                        kl_mean = torch.mean(kl)
-
-                        if kl_mean > self.desired_kl * 2.0:
-                            self.learning_rate = max(1e-5, self.learning_rate / 1.5)
-                        elif kl_mean < self.desired_kl / 2.0 and kl_mean > 0.0:
-                            self.learning_rate = min(1e-2, self.learning_rate * 1.5)
-
-                        for param_group in self.optimizer.param_groups:
-                            param_group['lr'] = self.learning_rate
-
-
-                # Surrogate loss
-                ratio = torch.exp(actions_log_prob_batch - torch.squeeze(old_actions_log_prob_batch))
-                surrogate = -torch.squeeze(advantages_batch) * ratio
-                surrogate_clipped = -torch.squeeze(advantages_batch) * torch.clamp(ratio, 1.0 - self.clip_param,
-                                                                                1.0 + self.clip_param)
-                surrogate_loss = torch.max(surrogate, surrogate_clipped).mean()
-
-                # Value function loss
-                if self.use_clipped_value_loss:
-                    value_clipped = target_values_batch + (value_batch - target_values_batch).clamp(-self.clip_param,
-                                                                                                    self.clip_param)
-                    value_losses = (value_batch - returns_batch).pow(2)
-                    value_losses_clipped = (value_clipped - returns_batch).pow(2)
-                    value_loss = torch.max(value_losses, value_losses_clipped).mean()
-                else:
-                    value_loss = (returns_batch - value_batch).pow(2).mean()
-
-                loss = surrogate_loss + self.value_loss_coef * value_loss - self.entropy_coef * entropy_batch.mean()
-
-                # Gradient step
-                self.optimizer.zero_grad()
-                loss.backward()
-                nn.utils.clip_grad_norm_(self.actor_critic.parameters(), self.max_grad_norm)
-                self.optimizer.step()
-
-                mean_value_loss += value_loss.item()
-                mean_surrogate_loss += surrogate_loss.item()
+        for (
+            obs_batch,
+            critic_obs_batch,
+            actions_batch,
+            target_values_batch,
+            advantages_batch,
+            returns_batch,
+            old_actions_log_prob_batch,
+            old_mu_batch,
+            old_sigma_batch,
+            hid_states_batch,
+            masks_batch,
+        ) in generator:
+
+            self.actor_critic.act(obs_batch, masks=masks_batch, hidden_states=hid_states_batch[0])
+            actions_log_prob_batch = self.actor_critic.get_actions_log_prob(actions_batch)
+            value_batch = self.actor_critic.evaluate(
+                critic_obs_batch, masks=masks_batch, hidden_states=hid_states_batch[1]
+            )
+            mu_batch = self.actor_critic.action_mean
+            sigma_batch = self.actor_critic.action_std
+            entropy_batch = self.actor_critic.entropy
+
+            # KL
+            if self.desired_kl is not None and self.schedule == "adaptive":
+                with torch.inference_mode():
+                    kl = torch.sum(
+                        torch.log(sigma_batch / old_sigma_batch + 1.0e-5)
+                        + (torch.square(old_sigma_batch) + torch.square(old_mu_batch - mu_batch))
+                        / (2.0 * torch.square(sigma_batch))
+                        - 0.5,
+                        axis=-1,
+                    )
+                    kl_mean = torch.mean(kl)
+
+                    if kl_mean > self.desired_kl * 2.0:
+                        self.learning_rate = max(1e-5, self.learning_rate / 1.5)
+                    elif kl_mean < self.desired_kl / 2.0 and kl_mean > 0.0:
+                        self.learning_rate = min(1e-2, self.learning_rate * 1.5)
+
+                    for param_group in self.optimizer.param_groups:
+                        param_group["lr"] = self.learning_rate
+
+            # Surrogate loss
+            ratio = torch.exp(actions_log_prob_batch - torch.squeeze(old_actions_log_prob_batch))
+            surrogate = -torch.squeeze(advantages_batch) * ratio
+            surrogate_clipped = -torch.squeeze(advantages_batch) * torch.clamp(
+                ratio, 1.0 - self.clip_param, 1.0 + self.clip_param
+            )
+            surrogate_loss = torch.max(surrogate, surrogate_clipped).mean()
+
+            # Value function loss
+            if self.use_clipped_value_loss:
+                value_clipped = target_values_batch + (value_batch - target_values_batch).clamp(
+                    -self.clip_param, self.clip_param
+                )
+                value_losses = (value_batch - returns_batch).pow(2)
+                value_losses_clipped = (value_clipped - returns_batch).pow(2)
+                value_loss = torch.max(value_losses, value_losses_clipped).mean()
+            else:
+                value_loss = (returns_batch - value_batch).pow(2).mean()
+
+            loss = surrogate_loss + self.value_loss_coef * value_loss - self.entropy_coef * entropy_batch.mean()
+
+            # Gradient step
+            self.optimizer.zero_grad()
+            loss.backward()
+            nn.utils.clip_grad_norm_(self.actor_critic.parameters(), self.max_grad_norm)
+            self.optimizer.step()
+
+            mean_value_loss += value_loss.item()
+            mean_surrogate_loss += surrogate_loss.item()
 
         num_updates = self.num_learning_epochs * self.num_mini_batches
         mean_value_loss /= num_updates

rsl_rl/env/__init__.py

@@ -1,4 +1,7 @@
 #  Copyright 2021 ETH Zurich, NVIDIA CORPORATION
 #  SPDX-License-Identifier: BSD-3-Clause
+"""Submodule defining the environment definitions."""
 
-from .vec_env import VecEnv
+from .vec_env import VecEnv
+
+__all__ = ["VecEnv"]

rsl_rl/env/vec_env.py

@@ -1,10 +1,14 @@
 #  Copyright 2021 ETH Zurich, NVIDIA CORPORATION
 #  SPDX-License-Identifier: BSD-3-Clause
 
+# python
 from abc import ABC, abstractmethod
-import torch
 from typing import Tuple, Union
 
+# torch
+import torch
+
+
 # minimal interface of the environment
 class VecEnv(ABC):
     """Abstract class for vectorized environment."""
@@ -18,7 +22,7 @@ class VecEnv(ABC):
     obs_buf: torch.Tensor
     rew_buf: torch.Tensor
     reset_buf: torch.Tensor
-    episode_length_buf: torch.Tensor # current episode duration
+    episode_length_buf: torch.Tensor  # current episode duration
     extras: dict
     device: torch.device
 
@@ -29,6 +33,7 @@ class VecEnv(ABC):
     @abstractmethod
     def get_observations(self) -> torch.Tensor:
         pass
+
     @abstractmethod
     def get_privileged_observations(self) -> Union[torch.Tensor, None]:
         pass

rsl_rl/modules/__init__.py

@@ -1,5 +1,9 @@
 #  Copyright 2021 ETH Zurich, NVIDIA CORPORATION
 #  SPDX-License-Identifier: BSD-3-Clause
 
+"""Definitions for neural-network components for RL-agents."""
+
 from .actor_critic import ActorCritic
-from .actor_critic_recurrent import ActorCriticRecurrent
+from .actor_critic_recurrent import ActorCriticRecurrent
+
+__all__ = ["ActorCritic", "ActorCriticRecurrent"]