def debye_E(x):
    """
    calculate Debye energy using old fortran routine

    :params x: Debye x value
    :return: Debye energy
    :note: this is a wraper function (vectorization) for debye_E_single
    """
    if isuncertainties([x]):
        f_u = uct.wrap(debye_E_single)
        f_v = np.vectorize(f_u)
    else:
        f_v = np.vectorize(debye_E_single)
    return f_v(x)