def curvature_from_fit(fit, y):
    """Compute curvature radius

    Args:
        fit (numpy.ndarray[3]<float>): polynomial regression fit coefficients
        y (float): point where curvature will be evaluated

    Returns:
        float: curvature radius
    """

    if len(fit) != 3:
        raise AssertionError(f"expected fit coefficients to be of shape (3,), but received {fit.shape}")

    f_prime = 2 * fit[0] * y + fit[1]
    f_second = 2 * fit[0]
    return (1 + (f_prime ** 2)) ** 1.5 / abs(f_second)