Merge remote-tracking branch 'upstream/main' into fix_pusht_diffusion

lerobot/scripts/train.py

@@ -12,7 +12,7 @@ from lerobot.common.datasets.factory import make_offline_buffer
 from lerobot.common.envs.factory import make_env
 from lerobot.common.logger import Logger, log_output_dir
 from lerobot.common.policies.factory import make_policy
-from lerobot.common.utils import format_big_number, init_logging, set_seed
+from lerobot.common.utils import format_big_number, get_safe_torch_device, init_logging, set_seed
 from lerobot.scripts.eval import eval_policy
 
 
@@ -112,13 +112,13 @@ def train(cfg: dict, out_dir=None, job_name=None):
         raise NotImplementedError()
     if job_name is None:
         raise NotImplementedError()
+    if cfg.online_steps > 0:
+        assert cfg.rollout_batch_size == 1, "rollout_batch_size > 1 not supported for online training steps"
 
     init_logging()
 
-    if cfg.device == "cuda":
-        assert torch.cuda.is_available()
-    else:
-        logging.warning("Using CPU, this will be slow.")
+    # Check device is available
+    get_safe_torch_device(cfg.device, log=True)
 
     torch.backends.cudnn.benchmark = True
     torch.backends.cuda.matmul.allow_tf32 = True
@@ -220,11 +220,11 @@ def train(cfg: dict, out_dir=None, job_name=None):
         # TODO: add configurable number of rollout? (default=1)
         with torch.no_grad():
             rollout = env.rollout(
-                max_steps=cfg.env.episode_length // cfg.n_action_steps,
+                max_steps=cfg.env.episode_length,
                 policy=td_policy,
                 auto_cast_to_device=True,
             )
-        assert len(rollout) <= cfg.env.episode_length // cfg.n_action_steps
+        assert len(rollout) <= cfg.env.episode_length
         # set same episode index for all time steps contained in this rollout
         rollout["episode"] = torch.tensor([env_step] * len(rollout), dtype=torch.int)
         online_buffer.extend(rollout)