states.kalman.project.mahalanobis_d2
def mahalanobis_d2(cs_field: torch.Tensor, cs_cov: torch.Tensor, ds_field: torch.Tensor, label: str) -> torch.TensorPairwise Mahalanobis chi-squared over a measurement subspace.
Truncates the state to ``ds_field``'s dimension (``H = [I, 0]``),
then solves :math:`\Sigma x = (a - b)` per pair and returns
:math:`(a - b)^T x`. Shared by :class:`Mahalanobis`,
:class:`~unitrack.gates.MotionGate`, and
:class:`~unitrack.gates.SoftMotionGate` so they agree on
the projection and PSD-guard conventions.
Parameters
| Name | Type | Description |
|---|---|---|
| cs_field | torch.Tensor | ``(N, D)`` tracklet mean. |
| cs_cov | torch.Tensor | ``(N, D, D)`` tracklet covariance. |
| ds_field | torch.Tensor | ``(M, d_meas)`` detection field. |
| label | str | Identifier embedded in :func:`solve_psd`'s error message. |
Returns
torch.Tensor — ``(N, M)`` pairwise chi-squared distances.
Source: unitrack/states/kalman/project.py:98