def curvature(dx, dy, ddx, ddy):
    """
    Compute curvature at one point given first and second derivatives.

    :param dx: (float) First derivative along x axis
    :param dy: (float)
    :param ddx: (float) Second derivative along x axis
    :param ddy: (float)
    :return: (float)
    """
    return (dx * ddy - dy * ddx) / (dx ** 2 + dy ** 2) ** (3 / 2)