Merge branch 'episodic-rl' of github.com:nicklashansen/tdmpc2 into episodic-rl

tdmpc2/common/buffer.py

@@ -78,7 +78,7 @@ class Buffer():
 		obs = td['obs']
 		action = td['action'][1:]
 		reward = td['reward'][1:].unsqueeze(-1)
-		terminated = td['terminated'][1:].unsqueeze(-1)
+		terminated = td['terminated'][-1].unsqueeze(-1)
 		task = td['task'][0] if 'task' in td.keys() else None
 		return self._to_device(obs, action, reward, terminated, task)
 

tdmpc2/config.yaml

@@ -2,8 +2,9 @@ defaults:
     - override hydra/launcher: submitit_local
 
 # environment
-task: dog-run
+task: cartpole-balance-sparse
 obs: state
+episodic: true
 
 # evaluation
 checkpoint: ???

tdmpc2/envs/dmcontrol.py

@@ -10,6 +10,8 @@ from dm_control.suite.wrappers import action_scale
 from dm_env import StepType, specs
 import gym
 
+from envs.wrappers.episodic import EpisodicWrapper
+
 
 class ExtendedTimeStep(NamedTuple):
 	step_type: Any
@@ -197,4 +199,6 @@ def make_env(cfg):
 	env = action_scale.Wrapper(env, minimum=-1., maximum=1.)
 	env = ExtendedTimeStepWrapper(env)
 	env = TimeStepToGymWrapper(env, domain, task)
+	if cfg.episodic:
+		env = EpisodicWrapper(cfg, env)
 	return env

tdmpc2/envs/wrappers/episodic.py

@@ -0,0 +1,24 @@
+from collections import deque
+
+import gym
+import numpy as np
+import torch
+
+
+class EpisodicWrapper(gym.Wrapper):
+	"""
+	Wrapper for testing episodic tasks. Only compatible with cartpole-balance-sparse at the moment.
+	"""
+
+	def __init__(self, cfg, env):
+		super().__init__(env)
+		assert cfg.task == 'cartpole-balance-sparse'
+		self.cfg = cfg
+		self.env = env
+
+	def step(self, action):
+		obs, reward, done, info = self.env.step(action)
+		if self.cfg.episodic and reward == 0:
+			done = True
+			info['terminated'] = True
+		return obs, reward, done, info

tdmpc2/tdmpc2.py

@@ -230,7 +230,7 @@ class TDMPC2:
 			dict: Dictionary of training statistics.
 		"""
 		obs, action, reward, terminated, task = buffer.sample()
-	
+		
 		# Compute targets
 		with torch.no_grad():
 			next_z = self.model.encode(obs[1:], task)
@@ -254,15 +254,16 @@ class TDMPC2:
 		_zs = zs[:-1]
 		qs = self.model.Q(_zs, action, task, return_type='all')
 		reward_preds = self.model.reward(_zs, action, task)
-		terminated_preds = self.model.terminated(_zs, task)
+		terminated_pred = self.model.terminated(zs[-1], task)
-		
+
 		# Compute losses
 		reward_loss, terminated_loss, value_loss = 0, 0, 0
 		for t in range(self.cfg.horizon):
 			reward_loss += math.soft_ce(reward_preds[t], reward[t], self.cfg).mean() * self.cfg.rho**t
-			terminated_loss += F.binary_cross_entropy(terminated_preds[t], terminated[t]) * self.cfg.rho**t
+			terminated_loss += F.binary_cross_entropy(terminated_pred[t], terminated[t]) * self.cfg.rho**t
 			for q in range(self.cfg.num_q):
 				value_loss += math.soft_ce(qs[q][t], td_targets[t], self.cfg).mean() * self.cfg.rho**t
+		terminated_loss = F.binary_cross_entropy(terminated_pred, terminated)
 		consistency_loss *= (1/self.cfg.horizon)
 		reward_loss *= (1/self.cfg.horizon)
 		terminated_loss *= (1/self.cfg.horizon)

tdmpc2/train.py

@@ -46,6 +46,9 @@ def train(cfg: dict):
 	set_seed(cfg.seed)
 	print(colored('Work dir:', 'yellow', attrs=['bold']), cfg.work_dir)
 
+	assert cfg.task == 'cartpole-balance-sparse' and cfg.episodic, \
+		f'This branch is experimental and only supports cartpole-balance-sparse at this time.'
+
 	trainer_cls = OfflineTrainer if cfg.multitask else OnlineTrainer
 	trainer = trainer_cls(
 		cfg=cfg,

tdmpc2/trainer/online_trainer.py

@@ -47,10 +47,8 @@ class OnlineTrainer(Trainer):
 			episode_success=np.nanmean(ep_successes),
 		)
 
-	def to_td(self, obs=None, action=None, reward=None, terminated=None):
+	def to_td(self, obs, action=None, reward=None, terminated=None):
 		"""Creates a TensorDict for a new episode."""
-		if obs is None:
-			obs = torch.full((*self.cfg.obs_shape[self.cfg.obs],), float('nan'))
 		if isinstance(obs, dict):
 			obs = TensorDict(obs, batch_size=(), device='cpu')
 		else:
@@ -93,7 +91,6 @@ class OnlineTrainer(Trainer):
 					)
 					train_metrics.update(self.common_metrics())
 					self.logger.log(train_metrics, 'train')
-					self._tds.append(self.to_td()) # Separate episodes with NaNs
 					self._ep_idx = self.buffer.add(torch.cat(self._tds))
 
 				obs = self.env.reset()