keras-team/keras · error · ValueError

Shapes are incompatible for associative_scan interleaving. a

Error message

Shapes are incompatible for associative_scan interleaving. a.shape[{axis}]={a.shape[axis]}, b.shape[{axis}]={b.shape[axis]}

What it means

Error "Shapes are incompatible for associative_scan interleaving. a.shape[{axis}]={a.shape[axis]}, b.shape[{axis}]={b.shape[axis]}" thrown in keras-team/keras.

Source

Thrown at keras/src/backend/numpy/core.py:245

        c = f(a, b)
        c_flat = tree.flatten(c)
        return c_flat

    num_elems = int(elems_flat[0].shape[axis])
    if not all(int(elem.shape[axis]) == num_elems for elem in elems_flat[1:]):
        raise ValueError(
            "Array inputs to associative_scan must have the same "
            "first dimension. (saw: {})".format(
                [elem.shape for elem in elems_flat]
            )
        )

    def _interleave(a, b, axis):
        """Given two Tensors of static shape, interleave them along axis."""
        if not (
            a.shape[axis] == b.shape[axis] or a.shape[axis] == b.shape[axis] + 1
        ):
            raise ValueError(
                "Shapes are incompatible for associative_scan interleaving. "
                f"a.shape[{axis}]={a.shape[axis]}, "
                f"b.shape[{axis}]={b.shape[axis]}"
            )

        # we want to get a: [a1, a2], b: [b1, b2]
        # to a: [a1, 0, a2, 0], b: [0, b1, 0, b2]
        a_shape = list(a.shape)
        a_shape[axis] = a.shape[axis] * 2 - 1

        b_shape = list(b.shape)
        b_shape[axis] = b.shape[axis] * 2 - 1

        a_dil = np.zeros(a_shape)
        np.copyto(slice_along_axis(a_dil, 0, None, 2, axis), a)
        b_dil = np.zeros(b_shape)
        np.copyto(slice_along_axis(b_dil, 0, None, 2, axis), b)

View on GitHub (pinned to 7a34a03db6)

When it happens

Trigger: Thrown at keras/src/backend/numpy/core.py:245 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of keras-team/keras@7a34a03db6 (2026-08-25). Data as JSON: /api/errors/faed65a8410b6520. Report an issue: GitHub.