fix(logging): remove unused list-valued metric expansion

- Wrap cast_stats_to_numpy with np.atleast_1d to prevent 0-d arrays
from scalar stats causing shape mismatches downstream.

src/lerobot/common/wandb_utils.py

@@ -180,24 +180,26 @@ class WandBLogger:
                 self._wandb_custom_step_key.add(new_custom_key)
                 self._wandb.define_metric(new_custom_key, hidden=True)
 
+        batch_data = {}
         for k, v in d.items():
+            # Skip the custom step key here, it's added to the batch below.
+            if custom_step_key is not None and k == custom_step_key:
+                continue
+
             if not isinstance(v, (int | float | str)):
                 logging.warning(
                     f'WandB logging of key "{k}" was ignored as its type "{type(v)}" is not handled by this wrapper.'
                 )
                 continue
 
-            # Do not log the custom step key itself.
-            if self._wandb_custom_step_key is not None and k in self._wandb_custom_step_key:
-                continue
+            batch_data[f"{mode}/{k}"] = v
 
+        if batch_data:
             if custom_step_key is not None:
-                value_custom_step = d[custom_step_key]
-                data = {f"{mode}/{k}": v, f"{mode}/{custom_step_key}": value_custom_step}
-                self._wandb.log(data)
-                continue
-
-            self._wandb.log(data={f"{mode}/{k}": v}, step=step)
+                batch_data[f"{mode}/{custom_step_key}"] = d[custom_step_key]
+                self._wandb.log(batch_data)
+            else:
+                self._wandb.log(data=batch_data, step=step)
 
     def log_video(self, video_path: str, step: int, mode: str = "train"):
         if mode not in {"train", "eval"}:

src/lerobot/configs/default.py

@@ -73,8 +73,6 @@ class EvalConfig:
     # `use_async_envs` specifies whether to use asynchronous environments (multiprocessing).
     # Defaults to True; automatically downgraded to SyncVectorEnv when batch_size=1.
     use_async_envs: bool = True
-    # Whether to record eval rollouts as a LeRobot v3.0 dataset on disk.
-    recording: bool = False
 
     def __post_init__(self) -> None:
         if self.batch_size == 0:

src/lerobot/datasets/io_utils.py

@@ -153,7 +153,7 @@ def cast_stats_to_numpy(stats: dict) -> dict[str, dict[str, np.ndarray]]:
     Returns:
         dict: The statistics dictionary with values cast to numpy arrays.
     """
-    stats = {key: np.array(value) for key, value in flatten_dict(stats).items()}
+    stats = {key: np.atleast_1d(np.array(value)) for key, value in flatten_dict(stats).items()}
     return unflatten_dict(stats)
 
 

src/lerobot/scripts/lerobot_eval.py

@@ -72,9 +72,8 @@ from termcolor import colored
 from torch import Tensor, nn
 from tqdm import trange
 
-from lerobot.configs import FeatureType, parser
+from lerobot.configs import parser
 from lerobot.configs.eval import EvalPipelineConfig
-from lerobot.datasets.lerobot_dataset import LeRobotDataset
 from lerobot.envs import (
     check_env_attributes_and_types,
     close_envs,
@@ -85,7 +84,7 @@ from lerobot.envs import (
 from lerobot.policies import PreTrainedPolicy, make_policy, make_pre_post_processors
 from lerobot.processor import PolicyProcessorPipeline
 from lerobot.types import PolicyAction
-from lerobot.utils.constants import ACTION, DONE, OBS_IMAGE, OBS_IMAGES, OBS_STR, REWARD
+from lerobot.utils.constants import ACTION, DONE, OBS_STR, REWARD
 from lerobot.utils.device_utils import get_safe_torch_device
 from lerobot.utils.import_utils import register_third_party_plugins
 from lerobot.utils.io_utils import write_video
@@ -96,81 +95,6 @@ from lerobot.utils.utils import (
 )
 
 
-def _env_features_to_dataset_features(env_features: dict, raw_obs: dict | None = None) -> dict:
-    """Convert EnvConfig.features (PolicyFeature objects) to the plain dict format for LeRobotDataset.create().
-
-    If raw_obs is provided, visual feature shapes are inferred from the actual observation
-    to avoid mismatches between the env config and the real observation resolution.
-    """
-    features = {}
-    for key, ft in env_features.items():
-        if ft.type is FeatureType.VISUAL:
-            shape = tuple(ft.shape)
-            if raw_obs is not None and key in raw_obs and isinstance(raw_obs[key], np.ndarray):
-                shape = raw_obs[key].shape[1:]  # strip batch dim
-            elif raw_obs is not None and "pixels" in raw_obs:
-                pixels = raw_obs["pixels"]
-                if isinstance(pixels, dict):
-                    for cam_name, img in pixels.items():
-                        if key == f"{OBS_IMAGES}.{cam_name}" or key == cam_name:
-                            shape = img.shape[1:]  # strip batch dim
-                elif key in ("pixels", OBS_IMAGE):
-                    shape = pixels.shape[1:]  # strip batch dim
-            features[key] = {"dtype": "video", "shape": shape, "names": ["height", "width", "channel"]}
-        else:
-            shape = tuple(ft.shape)
-            if raw_obs is not None and key in raw_obs and isinstance(raw_obs[key], np.ndarray):
-                shape = raw_obs[key].shape[1:]  # strip batch dim
-            features[key] = {"dtype": "float32", "shape": shape, "names": None}
-    features["next.reward"] = {"dtype": "float32", "shape": (1,), "names": None}
-    features["next.success"] = {"dtype": "bool", "shape": (1,), "names": None}
-    features["next.done"] = {"dtype": "bool", "shape": (1,), "names": None}
-    return features
-
-
-def _build_raw_frame(
-    raw_obs: dict,
-    env_idx: int,
-    action: np.ndarray,
-    reward: float,
-    success: bool,
-    done: bool,
-    task: str,
-    env_features: dict,
-) -> dict:
-    """Build a dataset frame from raw env observations for one env index.
-
-    Keys in the frame match the keys in env_features so they align with the
-    dataset schema created by _env_features_to_dataset_features().
-    """
-    frame: dict[str, Any] = {}
-    for key in env_features:
-        if key == ACTION:
-            continue
-        if "pixels" in raw_obs and isinstance(raw_obs["pixels"], dict):
-            for cam_name, img in raw_obs["pixels"].items():
-                candidate = f"{OBS_IMAGES}.{cam_name}"
-                if candidate == key:
-                    frame[key] = img[env_idx]
-            if key in frame:
-                continue
-        if "pixels" in raw_obs and not isinstance(raw_obs["pixels"], dict) and key in ("pixels", OBS_IMAGE):
-            frame[key] = raw_obs["pixels"][env_idx]
-            continue
-        raw_key = key
-        if raw_key in raw_obs and isinstance(raw_obs[raw_key], np.ndarray):
-            val = raw_obs[raw_key][env_idx]
-            if val.dtype == np.float64:
-                val = val.astype(np.float32)
-            frame[key] = val
-    frame[ACTION] = action
-    frame["next.reward"] = np.atleast_1d(np.float32(reward))
-    frame["next.success"] = np.atleast_1d(np.bool_(success))
-    frame["next.done"] = np.atleast_1d(np.bool_(done))
-    frame["task"] = task
-    return frame
-
-
 def rollout(
     env: gym.vector.VectorEnv,
     policy: PreTrainedPolicy,
@@ -181,7 +105,6 @@ def rollout(
     seeds: list[int] | None = None,
     return_observations: bool = False,
     render_callback: Callable[[gym.vector.VectorEnv], None] | None = None,
-    recording_dataset: Any | None = None,
 ) -> dict:
     """Run a batched policy rollout once through a batch of environments.
 
@@ -222,14 +145,6 @@ def rollout(
     if render_callback is not None:
         render_callback(env)
 
-    raw_observation = deepcopy(observation) if recording_dataset is not None else None
-    task_desc = ""
-    if recording_dataset is not None:
-        try:
-            task_desc = list(env.call("task_description"))[0]
-        except (AttributeError, NotImplementedError):
-            task_desc = ""
-
     all_observations = []
     all_actions = []
     all_rewards = []
@@ -302,26 +217,6 @@ def rollout(
         else:
             successes = [False] * env.num_envs
 
-        if recording_dataset is not None and raw_observation is not None:
-            prev_done = done.copy()
-            for env_idx in range(env.num_envs):
-                if prev_done[env_idx]:
-                    continue
-                frame = _build_raw_frame(
-                    raw_observation,
-                    env_idx,
-                    action_numpy[env_idx],
-                    reward[env_idx],
-                    successes[env_idx],
-                    bool(terminated[env_idx] | truncated[env_idx]),
-                    task_desc,
-                    recording_dataset.features,
-                )
-                recording_dataset.add_frame(frame)
-                if terminated[env_idx] or truncated[env_idx]:
-                    recording_dataset.save_episode()
-            raw_observation = deepcopy(observation)
-
         # Keep track of which environments are done so far.
         # Mark the episode as done if we reach the maximum step limit.
         # This ensures that the rollout always terminates cleanly at `max_steps`,
@@ -378,7 +273,6 @@ def eval_policy(
     videos_dir: Path | None = None,
     return_episode_data: bool = False,
     start_seed: int | None = None,
-    recording_dataset: Any | None = None,
 ) -> dict:
     """
     Args:
@@ -467,7 +361,6 @@ def eval_policy(
             seeds=list(seeds) if seeds else None,
             return_observations=return_episode_data,
             render_callback=render_frame if max_episodes_rendered > 0 else None,
-            recording_dataset=recording_dataset,
         )
 
         # Figure out where in each rollout sequence the first done condition was encountered (results after
@@ -670,10 +563,6 @@ def eval_main(cfg: EvalPipelineConfig):
     # Create environment-specific preprocessor and postprocessor (e.g., for LIBERO environments)
     env_preprocessor, env_postprocessor = make_env_pre_post_processors(env_cfg=cfg.env, policy_cfg=cfg.policy)
 
-    recording_dir = Path(cfg.output_dir) / "recordings" if cfg.eval.recording else None
-    max_episodes_rendered = 0 if cfg.eval.recording else 10
-    videos_dir = None if cfg.eval.recording else Path(cfg.output_dir) / "videos"
-
     with torch.no_grad(), torch.autocast(device_type=device.type) if cfg.policy.use_amp else nullcontext():
         info = eval_policy_all(
             envs=envs,
@@ -683,13 +572,10 @@ def eval_main(cfg: EvalPipelineConfig):
             preprocessor=preprocessor,
             postprocessor=postprocessor,
             n_episodes=cfg.eval.n_episodes,
-            max_episodes_rendered=max_episodes_rendered,
-            videos_dir=videos_dir,
-            return_episode_data=False,
+            max_episodes_rendered=10,
+            videos_dir=Path(cfg.output_dir) / "videos",
             start_seed=cfg.seed,
             max_parallel_tasks=cfg.env.max_parallel_tasks,
-            recording_dir=recording_dir,
-            env_features=cfg.env.features if cfg.eval.recording else None,
         )
         print("Overall Aggregated Metrics:")
         print(info["overall"])
@@ -732,7 +618,6 @@ def eval_one(
     videos_dir: Path | None,
     return_episode_data: bool,
     start_seed: int | None,
-    recording_dataset: Any | None = None,
 ) -> TaskMetrics:
     """Evaluates one task_id of one suite using the provided vec env."""
 
@@ -750,7 +635,6 @@ def eval_one(
         videos_dir=task_videos_dir,
         return_episode_data=return_episode_data,
         start_seed=start_seed,
-        recording_dataset=recording_dataset,
     )
 
     per_episode = task_result["per_episode"]
@@ -777,8 +661,6 @@ def run_one(
     videos_dir: Path | None,
     return_episode_data: bool,
     start_seed: int | None,
-    recording_dir: Path | None = None,
-    env_features: dict | None = None,
 ):
     """
     Run eval_one for a single (task_group, task_id, env).
@@ -790,39 +672,21 @@ def run_one(
         task_videos_dir = videos_dir / f"{task_group}_{task_id}"
         task_videos_dir.mkdir(parents=True, exist_ok=True)
 
-    recording_dataset = None
-    if recording_dir is not None and env_features is not None:
-        task_recording_dir = recording_dir / f"{task_group}_{task_id}"
-        fps = env.unwrapped.metadata.get("render_fps", 30)
-        sample_obs, _ = env.reset()
-        features = _env_features_to_dataset_features(env_features, raw_obs=sample_obs)
-        recording_dataset = LeRobotDataset.create(
-            repo_id=f"eval_{task_group}_{task_id}",
-            fps=fps,
-            features=features,
-            root=str(task_recording_dir),
-            use_videos=True,
-        )
-
-    try:
-        metrics = eval_one(
-            env,
-            policy=policy,
-            env_preprocessor=env_preprocessor,
-            env_postprocessor=env_postprocessor,
-            preprocessor=preprocessor,
-            postprocessor=postprocessor,
-            n_episodes=n_episodes,
-            max_episodes_rendered=max_episodes_rendered,
-            videos_dir=task_videos_dir,
-            return_episode_data=return_episode_data,
-            start_seed=start_seed,
-            recording_dataset=recording_dataset,
-        )
-    finally:
-        if recording_dataset is not None:
-            recording_dataset.finalize()
-
+    # Call the existing eval_one (assumed to return TaskMetrics-like dict)
+    metrics = eval_one(
+        env,
+        policy=policy,
+        env_preprocessor=env_preprocessor,
+        env_postprocessor=env_postprocessor,
+        preprocessor=preprocessor,
+        postprocessor=postprocessor,
+        n_episodes=n_episodes,
+        max_episodes_rendered=max_episodes_rendered,
+        videos_dir=task_videos_dir,
+        return_episode_data=return_episode_data,
+        start_seed=start_seed,
+    )
+    # ensure we always provide video_paths key to simplify accumulation
     if max_episodes_rendered > 0:
         metrics.setdefault("video_paths", [])
     return task_group, task_id, metrics
@@ -838,8 +702,6 @@ def eval_policy_all(
     n_episodes: int,
     *,
     max_episodes_rendered: int = 0,
-    recording_dir: Path | None = None,
-    env_features: dict | None = None,
     videos_dir: Path | None = None,
     return_episode_data: bool = False,
     start_seed: int | None = None,
@@ -899,8 +761,6 @@ def eval_policy_all(
         videos_dir=videos_dir,
         return_episode_data=return_episode_data,
         start_seed=start_seed,
-        recording_dir=recording_dir,
-        env_features=env_features,
     )
 
     if max_parallel_tasks <= 1: