dataset_card.md

# Dataset Card: SparseWake

## Dataset Name

SparseWake

## Intended Use

Evaluation of sparse temporal hydrodynamic state estimation from body-fixed induced-flow histories.

## Not Intended Use

SparseWake is not a full biological lateral-line pressure model, a multi-neighbor schooling model, or a replacement for direct CFD solvers.

## Data Source

The processed data were generated from WakeSchool, an external fish-schooling simulator with DNS-parameterized wake and body-flow components. The artifact starts from processed HDF5 benchmark datasets and does not redistribute simulator source code.

## Released Fields

- `X_raw`: wake-plus-potential induced velocity features, sample shape `[N, 6, 3]` after loading.
- `X_wake_raw`: wake-only induced velocity features where available.
- `X_potential_raw`: potential-only induced velocity features where available.
- `X_external_raw`, `X_self_raw`, `X_total_raw`: self-signal controls where available.
- `y`: labels with columns `delta_x`, `delta_y`, `theta_rel`, `sin_phi`, `cos_phi`, `phi`.
- `groups`: wake phase index.
- `pose_id`: pose index for pose-holdout splitting in the sample dataset; full datasets can derive it from phase blocks.
- `region_id`: region code for close wake, near side, and mid wake.
- `sensor_world_positions`: sensor coordinates for each sample.

## Units and Conventions

Lengths are nondimensionalized by fish body length. Angles are stored in radians. Reported orientation metrics use degrees. The fish body is represented with semi-axes `a = 0.5 L` and `b = 0.075 L`.

## Sensor Layout

Six body-fixed sensors are arranged as anterior, midbody, and posterior left/right pairs. Sensor names are stored in documentation and sample HDF5 attributes.

## Train/Validation/Test Protocol

Main results use a held-out-pose test protocol. For each seed, 20% of follower pose identities are assigned to the test set, and all saved wake phases for those poses are withheld from training. The remaining non-test samples are split into training and validation with a 15% validation fraction. Thus the test set is pose-disjoint from training, while training and validation may contain different phases of the same non-test pose.

## Known Limitations

The current benchmark uses induced velocity rather than pressure, pressure gradients, or wall shear. It is single-neighbor unless explicitly stated. Multi-neighbor assignment, closed-loop control, and biological self-filtering are outside the released benchmark.

## Ethical Considerations

The dataset is synthetic fluid-dynamics data. It contains no human subjects, no animal measurements, and no personal data.