> ## Documentation Index
> Fetch the complete documentation index at: https://docs.almond.bot/llms.txt
> Use this file to discover all available pages before exploring further.

# migrate-dataset

> Migrate Cartesian datasets recorded before the v0.1.32 URDF frame change.

`axol migrate-dataset` updates Cartesian LeRobot datasets recorded with axol
v0.1.31 or earlier so they replay correctly with v0.1.32 and later.

In v0.1.32, the URDF root gained a +90° yaw so its world frame is FLU (+x
forward, +y left, +z up). Older Cartesian datasets store poses in the previous
frame. The migration applies that root transform to the position and
orientation of both end effectors in `action` and `observation.state`. It does
not alter videos, gripper values, timestamps, or joint-space datasets.

```bash theme={null}
# Inspect the dataset and report the scope without changing it
axol migrate-dataset --repo_id ilanri/checkers-demo-bimanual \
  --from-version v0.1.29 --dry-run

# Migrate it in place
axol migrate-dataset --repo_id ilanri/checkers-demo-bimanual \
  --from-version v0.1.29

# A dataset outside $HF_LEROBOT_HOME can be addressed directly
axol migrate-dataset --repo_id /data/checkers-demo-bimanual \
  --from-version v0.1.29
```

The command updates every data parquet, recomputes per-episode and global
statistics, and writes `meta/axol.json` to prevent accidental double migration.
Before making changes it backs up every file it will replace under
`meta/migrations/axol-urdf-root-yaw-v0.1.32/`. If migration fails, those files
are restored automatically; a later run also recovers an interrupted migration
before retrying.

Only run this on Cartesian data recorded with axol v0.1.31 or earlier. A
joint-space dataset does not need migration and is rejected. Legacy datasets do
not record their axol version, so recording provenance is the reliable way to
decide whether an unmarked dataset needs it. Fresh Cartesian datasets now write
their pose-frame provenance to `meta/axol.json` automatically.

`--from-version` is required because datasets made before pose-frame metadata
was added cannot distinguish pre-v0.1.32 data that needs migration from later
data that is already correct. The command rejects v0.1.32 and newer values.

## Options

| Option                     | Description                                                                    |
| -------------------------- | ------------------------------------------------------------------------------ |
| `--repo_id <id-or-path>`   | Local repo id under `$HF_LEROBOT_HOME`, or a dataset directory path (required) |
| `--root <path>`            | Alternate root containing the repo id                                          |
| `--from-version <version>` | Axol version that recorded the dataset; must be older than v0.1.32 (required)  |
| `--dry-run`                | Validate and report the files/rows that would change without writing           |