jax-ml/jax · error · ValueError

points have dimension {}, dataset has dimension {}

Error message

points have dimension {}, dataset has dimension {}

What it means

When evaluating a gaussian_kde, points are atleast_2d'd and their leading dimension must equal the KDE dimensionality self.d. A convenience case reshapes a single point given as a d-length row vector; any other mismatch (e.g. m points supplied as (m, d) instead of (d, m)) raises this error.

Source

Thrown at jax/_src/scipy/stats/kde.py:242

        "only 1D box integrations are supported; use `integrate_box_1d`")

  def set_bandwidth(self, bw_method=None):
    """This method is not implemented in the JAX interface."""
    del bw_method
    raise NotImplementedError(
        "dynamically changing the bandwidth method is not supported")

  def _reshape_points(self, points):
    if dtypes.issubdtype(lax.dtype(points), np.complexfloating):
      raise NotImplementedError(
          "gaussian_kde does not support complex coordinates")
    points = jnp.atleast_2d(points)
    d, m = points.shape
    if d != self.d:
      if d == 1 and m == self.d:
        points = jnp.reshape(points, (self.d, 1))
      else:
        raise ValueError(
            "points have dimension {}, dataset has dimension {}".format(
                d, self.d))
    return points


def _gaussian_kernel_convolve(chol, norm, target, weights, mean):
  diff = target - mean[:, None]
  alpha = linalg.cho_solve(chol, diff)
  arg = 0.5 * jnp.sum(diff * alpha, axis=0)
  return norm * jnp.sum(jnp.exp(-arg) * weights)


@api.jit(static_argnums=0)
def _gaussian_kernel_eval(in_log, points, values, xi, precision):
  points, values, xi, precision = promote_dtypes_inexact(
      points, values, xi, precision)
  d = points.shape[1]

View on GitHub (pinned to 1e1c6a8fc0)

Solutions

  1. Transpose the query points: kde.evaluate(X.T)
  2. For a single point pass a flat d-vector: kde.evaluate(p) with p.shape == (d,)
  3. Check d with kde.d and shape points accordingly

Example fix

// before
 dens = kde.evaluate(X)  # X.shape == (N, d)
// after
dens = kde.evaluate(X.T)  # (d, N)
Defensive patterns

Strategy: validation

Validate before calling

pts = jnp.asarray(points)
if pts.ndim == 2 and pts.shape[0] != kde.d:
    pts = pts.T  # assume (N, d) input
assert pts.shape[0] == kde.d

Type guard

def points_oriented_for_kde(points, kde) -> bool:
    p = jnp.atleast_2d(jnp.asarray(points))
    return p.shape[0] == kde.d or (p.shape[0] == 1 and p.shape[1] == kde.d)

Prevention

When it happens

Trigger: Calling kde.evaluate(X) with X.shape == (n_points, d) instead of (d, n_points); passing a single point of shape (d,) is fine, but (n_points,) with n_points != d fails.

Common situations: Feeding machine-learning-style (samples, features) arrays directly; the KDE stores dataset as (d, n) via atleast_2d so users must transpose their points.

Related errors


AI-assisted analysis of jax-ml/jax@1e1c6a8fc0 (2026-08-27). Data as JSON: /api/errors/27053fdd562bae39. Report an issue: GitHub.