keras-team/keras · error · ValueError

axis {axis} is out of bounds for an array with dimension {nu

Error message

axis {axis} is out of bounds for an array with dimension {num_dims}.

What it means

Error "axis {axis} is out of bounds for an array with dimension {num_dims}." thrown in keras-team/keras.

Source

Thrown at keras/src/backend/common/backend_utils.py:352

            strides=strides[i],
            padding=padding,
            output_padding=current_output_padding,
            dilation_rate=dilation_rate[i],
        )
        output_shape.append(shape_i)

    if data_format == "channels_last":
        output_shape = [input_shape[0]] + output_shape + [filters]
    else:
        output_shape = [input_shape[0], filters] + output_shape
    return output_shape


def canonicalize_axis(axis, num_dims):
    """Canonicalize an axis in [-num_dims, num_dims) to [0, num_dims)."""
    axis = operator.index(axis)
    if not -num_dims <= axis < num_dims:
        raise ValueError(
            f"axis {axis} is out of bounds for an array with dimension "
            f"{num_dims}."
        )
    if axis < 0:
        axis = axis + num_dims
    return axis


def canonicalize_axes(axis, num_dims):
    """Canonicalize an axis or axes to a tuple of non-negative integers."""
    if isinstance(axis, (tuple, list)):
        return tuple(canonicalize_axis(a, num_dims) for a in axis)
    return (canonicalize_axis(axis, num_dims),)


def standardize_axis_for_numpy(axis):
    """Standardize an axis to a tuple if it is a list in the numpy backend."""
    return tuple(axis) if isinstance(axis, list) else axis

View on GitHub (pinned to 7a34a03db6)

When it happens

Trigger: Thrown at keras/src/backend/common/backend_utils.py:352 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/12ee88358d5445c7. Report an issue: GitHub.