def test_episode_limit_with_vectorized_env_dataset(batch_size):
""" Test that when adding the EpisodeLimit wrapper on top of a vectorized
environment, the episode limit is with respect to each individual env rather
than the batched env.
"""
start = 0
target = 10
starting_values = [start for i in range(batch_size)]
targets = [target for i in range(batch_size)]
env = SyncVectorEnv([
partial(DummyEnvironment, start=start, target=target, max_value=10 * 2)
for start, target in zip(starting_values, targets)
])
max_episodes = 2
# TODO: For some reason the reverse order doesn't work!
env = EpisodeLimit(env, max_episodes=max_episodes * batch_size)
env = EnvDataset(env)
for i, obs in enumerate(env):
print(i, obs)
actions = np.ones(batch_size)
reward = env.send(actions)
assert i == max_episodes * target - 1
with pytest.raises(gym.error.ClosedEnvironmentError):
env.reset()
with pytest.raises(gym.error.ClosedEnvironmentError):
for i, obs in enumerate(env):
print(i, obs)
actions = np.ones(batch_size)
reward = env.send(actions)
def test_step_limit_with_vectorized_env(batch_size):
start = 0
target = 10
starting_values = [start for i in range(batch_size)]
targets = [target for i in range(batch_size)]
env = SyncVectorEnv([
partial(DummyEnvironment,
start=start,
target=target,
max_value=target * 2)
for start, target in zip(starting_values, targets)
])
env = ObservationLimit(env, max_steps=3 * batch_size)
obs = env.reset()
obs, reward, done, info = env.step(env.action_space.sample())
# obs, reward, done, info = env.step(env.action_space.sample())
obs = env.reset()
assert env.is_closed
with pytest.raises(gym.error.ClosedEnvironmentError):
env.reset()
with pytest.raises(gym.error.ClosedEnvironmentError):
_ = env.step(env.action_space.sample())
def test_reset_vectorenv_with_unfinished_episodes_raises_warning(batch_size):
""" Test that when adding the EpisodeLimit wrapper on top of a vectorized
environment, the episode limit is with respect to each individual env rather
than the batched env.
"""
start = 0
target = 10
starting_values = [start for i in range(batch_size)]
targets = [target for i in range(batch_size)]
env = SyncVectorEnv([
partial(DummyEnvironment, start=start, target=target, max_value=10 * 2)
for start, target in zip(starting_values, targets)
])
env = EpisodeLimit(env, max_episodes=3 * batch_size)
obs = env.reset()
_ = env.step(env.action_space.sample())
_ = env.step(env.action_space.sample())
with pytest.warns(UserWarning) as record:
env.reset()
def test_step_limit_with_vectorized_env_partial_final_batch(batch_size):
""" In the case where the batch size isn't a multiple of the max
observations, the env returns ceil(max_obs / batch_size) * batch_size
observations in total.
TODO: If we ever get to few-shot learning or something like that, we might
have to care about this.
"""
start = 0
target = 10
starting_values = [start for i in range(batch_size)]
targets = [target for i in range(batch_size)]
env = SyncVectorEnv([
partial(DummyEnvironment,
start=start,
target=target,
max_value=target * 2)
for start, target in zip(starting_values, targets)
])
env = ObservationLimit(env, max_steps=3 * batch_size + 1)
obs = env.reset()
assert not env.is_closed
obs, reward, done, info = env.step(env.action_space.sample())
obs, reward, done, info = env.step(env.action_space.sample())
assert not env.is_closed
# obs, reward, done, info = env.step(env.action_space.sample())
obs = env.reset()
assert env.is_closed
with pytest.raises(gym.error.ClosedEnvironmentError):
env.reset()
with pytest.raises(gym.error.ClosedEnvironmentError):
_ = env.step(env.action_space.sample())
def test_episode_limit_with_vectorized_env(batch_size):
""" Test that when adding the EpisodeLimit wrapper on top of a vectorized
environment, the episode limit is with respect to each individual env rather
than the batched env.
"""
starting_values = [0 for i in range(batch_size)]
targets = [10 for i in range(batch_size)]
env = SyncVectorEnv([
partial(DummyEnvironment, start=start, target=target, max_value=10 * 2)
for start, target in zip(starting_values, targets)
])
env = EpisodeLimit(env, max_episodes=2 * batch_size)
obs = env.reset()
assert obs.tolist() == starting_values
print("reset obs: ", obs)
for i in range(10):
print(i, obs)
actions = np.ones(batch_size)
obs, reward, done, info = env.step(actions)
# all episodes end at step 10
assert all(done)
# Because of how VectorEnvs work, the obs are the new 'reset' obs, rather
# than the final obs in the episode.
assert obs.tolist() == starting_values
assert obs.tolist() == starting_values
print("reset obs: ", obs)
for i in range(10):
print(i, obs)
actions = np.ones(batch_size)
obs, reward, done, info = env.step(actions)
# all episodes end at step 10
assert all(done)
assert env.is_closed
assert obs.tolist() == starting_values
with pytest.raises(gym.error.ClosedEnvironmentError):
actions = np.ones(batch_size)
obs, reward, done, info = env.step(actions)
def test_space_with_tuple_observations(batch_size: int, n_workers: Optional[int]):
def make_env():
env = gym.make("Breakout-v0")
env = MultiTaskEnvironment(
env, add_task_id_to_obs=True, add_task_dict_to_info=True
)
return env
env_fn = make_env
env_fns = [env_fn for _ in range(batch_size)]
# from gym.vector.utils import batch_space
# env = BatchedVectorEnv(env_fns, n_workers=n_workers)
from gym.vector import SyncVectorEnv
env = SyncVectorEnv(env_fns) # FIXME: debugging
# env = AsyncVectorEnv(env_fns)
env.seed(123)
assert env.observation_space == spaces.Dict(
x=spaces.Box(0, 255, (batch_size, 210, 160, 3), np.uint8),
task_labels=spaces.MultiDiscrete(np.ones(batch_size)),
)
assert env.single_observation_space == spaces.Dict(
x=spaces.Box(0, 255, (210, 160, 3), np.uint8),
task_labels=spaces.Discrete(1)
)
obs = env.reset()
assert obs["x"].shape == env.observation_space["x"].shape
assert obs["task_labels"].shape == env.observation_space["task_labels"].shape
assert obs in env.observation_space
actions = env.action_space.sample()
step_obs, rewards, done, info = env.step(actions)
assert step_obs in env.observation_space
assert len(rewards) == batch_size
assert len(done) == batch_size
assert all([isinstance(v, bool) for v in done.tolist()]), [type(v) for v in done]
assert len(info) == batch_size
def main(cfg):
random.seed(cfg.exp.seed)
np.random.seed(cfg.exp.seed)
torch.manual_seed(cfg.exp.seed)
torch.backends.cudnn.deterministic = cfg.exp.torch_deterministic
# so that the environment automatically resets
env = SyncVectorEnv([
lambda: RecordEpisodeStatistics(gym.make('CartPole-v1'))
])
actor, critic = Actor(), Critic()
actor_optim = Adam(actor.parameters(), eps=1e-5, lr=cfg.params.actor_lr)
critic_optim = Adam(critic.parameters(), eps=1e-5, lr=cfg.params.critic_lr)
memory = Memory(mini_batch_size=cfg.params.mini_batch_size, batch_size=cfg.params.batch_size)
obs = env.reset()
global_rewards = []
NUM_UPDATES = (cfg.params.total_timesteps // cfg.params.batch_size) * cfg.params.epochs
cur_timestep = 0
def calc_factor(cur_timestep: int) -> float:
"""Calculates the factor to be multiplied with the learning rate to update it."""
update_number = cur_timestep // cfg.params.batch_size
total_updates = cfg.params.total_timesteps // cfg.params.batch_size
fraction = 1.0 - update_number / total_updates
return fraction
actor_scheduler = LambdaLR(actor_optim, lr_lambda=calc_factor, verbose=True)
critic_scheduler = LambdaLR(critic_optim, lr_lambda=calc_factor, verbose=True)
while cur_timestep < cfg.params.total_timesteps:
# keep playing the game
obs = torch.as_tensor(obs, dtype=torch.float32)
with torch.no_grad():
dist = actor(obs)
action = dist.sample()
log_prob = dist.log_prob(action)
value = critic(obs)
action = action.cpu().numpy()
value = value.cpu().numpy()
log_prob = log_prob.cpu().numpy()
obs_, reward, done, info = env.step(action)
if done[0]:
tqdm.write(f'Reward: {info[0]["episode"]["r"]}, Avg Reward: {np.mean(global_rewards[-10:]):.3f}')
global_rewards.append(info[0]['episode']['r'])
wandb.log({'Avg_Reward': np.mean(global_rewards[-10:]), 'Reward': info[0]['episode']['r']})
memory.remember(obs.squeeze(0).cpu().numpy(), action.item(), log_prob.item(), reward.item(), done.item(), value.item())
obs = obs_
cur_timestep += 1
# if the current timestep is a multiple of the batch size, then we need to update the model
if cur_timestep % cfg.params.batch_size == 0:
for epoch in tqdm(range(cfg.params.epochs), desc=f'Num updates: {cfg.params.epochs * (cur_timestep // cfg.params.batch_size)} / {NUM_UPDATES}'):
# sample a batch from memory of experiences
old_states, old_actions, old_log_probs, old_rewards, old_dones, old_values, batch_indices = memory.sample()
old_log_probs = torch.tensor(old_log_probs, dtype=torch.float32)
old_actions = torch.tensor(old_actions, dtype=torch.float32)
advantage = calculate_advantage(old_rewards, old_values, old_dones, gae_gamma=cfg.params.gae_gamma, gae_lambda=cfg.params.gae_lambda)
advantage = torch.tensor(advantage, dtype=torch.float32)
old_rewards = torch.tensor(old_rewards, dtype=torch.float32)
old_values = torch.tensor(old_values, dtype=torch.float32)
# for each mini batch from batch, calculate advantage using GAE
for mini_batch_index in batch_indices:
# remember: Normalization of advantage is done on mini batch, not the entire batch
advantage[mini_batch_index] = (advantage[mini_batch_index] - advantage[mini_batch_index].mean()) / (advantage[mini_batch_index].std() + 1e-8)
dist = actor(torch.tensor(old_states[mini_batch_index], dtype=torch.float32).unsqueeze(0))
# actions = dist.sample()
log_probs = dist.log_prob(old_actions[mini_batch_index]).squeeze(0)
entropy = dist.entropy().squeeze(0)
log_ratio = log_probs - old_log_probs[mini_batch_index]
ratio = torch.exp(log_ratio)
with torch.no_grad():
# approx_kl = ((ratio-1)-log_ratio).mean()
approx_kl = ((old_log_probs[mini_batch_index] - log_probs)**2).mean()
wandb.log({'Approx_KL': approx_kl})
actor_loss = -torch.min(
ratio * advantage[mini_batch_index],
torch.clamp(ratio, 1 - cfg.params.actor_loss_clip, 1 + cfg.params.actor_loss_clip) * advantage[mini_batch_index]
).mean()
values = critic(torch.tensor(old_states[mini_batch_index], dtype=torch.float32).unsqueeze(0)).squeeze(-1)
returns = old_values[mini_batch_index] + advantage[mini_batch_index]
critic_loss = torch.max(
(values - returns)**2,
(old_values[mini_batch_index] + torch.clamp(
values - old_values[mini_batch_index], -cfg.params.critic_loss_clip, cfg.params.critic_loss_clip
) - returns
)**2
).mean()
# critic_loss = F.mse_loss(values, returns)
wandb.log({'Actor_Loss': actor_loss.item(), 'Critic_Loss': critic_loss.item(), 'Entropy': entropy.mean().item()})
loss = actor_loss + 0.25 * critic_loss - 0.01 * entropy.mean()
actor_optim.zero_grad()
critic_optim.zero_grad()
loss.backward()
nn.utils.clip_grad_norm_(actor.parameters(), cfg.params.max_grad_norm)
nn.utils.clip_grad_norm_(critic.parameters(), cfg.params.max_grad_norm)
actor_optim.step()
critic_optim.step()
memory.reset()
actor_scheduler.step(cur_timestep)
critic_scheduler.step(cur_timestep)
y_pred, y_true = old_values.cpu().numpy(), (old_values + advantage).cpu().numpy()
var_y = np.var(y_true)
explained_var = np.nan if var_y == 0 else 1 - np.var(y_true - y_pred) / var_y
wandb.log({'Explained_Var': explained_var})
if cfg.exp.save_weights:
torch.save(actor.state_dict(), Path(f'{hydra.utils.get_original_cwd()}/{cfg.exp.model_dir}/actor.pth'))
torch.save(critic.state_dict(), Path(f'{hydra.utils.get_original_cwd()}/{cfg.exp.model_dir}/critic.pth'))
