def Romeo_2002(Re, eD):
    r'''Calculates Darcy friction factor using the method in Romeo (2002)
    [2]_ as shown in [1]_.

    .. math::
        \frac{1}{\sqrt{f_d}} = -2\log\left\{\frac{\epsilon}{3.7065D}\times
        \frac{5.0272}{Re}\times\log\left[\frac{\epsilon}{3.827D} -
        \frac{4.567}{Re}\times\log\left(\frac{\epsilon}{7.7918D}^{0.9924} +
        \left(\frac{5.3326}{208.815+Re}\right)^{0.9345}\right)\right]\right\}

    Parameters
    ----------
    Re : float
        Reynolds number, [-]
    eD : float
        Relative roughness, [-]

    Returns
    -------
    fd : float
        Darcy friction factor [-]

    Notes
    -----
    Range is 3E3 <= Re <= 1.5E8;  0 <= eD <= 5E-2

    Examples
    --------
    >>> Romeo_2002(1E5, 1E-4)
    0.018530291219676177

    References
    ----------
    .. [1] Winning, H. and T. Coole. "Explicit Friction Factor Accuracy and
       Computational Efficiency for Turbulent Flow in Pipes." Flow, Turbulence
       and Combustion 90, no. 1 (January 1, 2013): 1-27.
       doi:10.1007/s10494-012-9419-7
    .. [2] Romeo, Eva, Carlos Royo, and Antonio Monzon."Improved Explicit
       Equations for Estimation of the Friction Factor in Rough and Smooth
       Pipes." Chemical Engineering Journal 86, no. 3 (April 28, 2002): 369-74.
       doi:10.1016/S1385-8947(01)00254-6.
    '''
    fd = (-2*log10(eD/3.7065-5.0272/Re*log10(eD/3.827-4.567/Re*log10((eD/7.7918)**0.9924+(5.3326/(208.815+Re))**0.9345))))**-2
    return fd
r'''Calculates Darcy friction factor using the method in Romeo (2002)
    [2]_ as shown in [1]_.

    .. math::
        \frac{1}{\sqrt{f_d}} = -2\log\left\{\frac{\epsilon}{3.7065D}\times
        \frac{5.0272}{Re}\times\log\left[\frac{\epsilon}{3.827D} -
        \frac{4.567}{Re}\times\log\left(\frac{\epsilon}{7.7918D}^{0.9924} +
        \left(\frac{5.3326}{208.815+Re}\right)^{0.9345}\right)\right]\right\}

    Parameters
    ----------
    Re : float
        Reynolds number, [-]
    eD : float
        Relative roughness, [-]

    Returns
    -------
    fd : float
        Darcy friction factor [-]

    Notes
    -----
    Range is 3E3 <= Re <= 1.5E8;  0 <= eD <= 5E-2

    Examples
    --------
    >>> Romeo_2002(1E5, 1E-4)
    0.018530291219676177

    References
    ----------
    .. [1] Winning, H. and T. Coole. "Explicit Friction Factor Accuracy and
       Computational Efficiency for Turbulent Flow in Pipes." Flow, Turbulence
       and Combustion 90, no. 1 (January 1, 2013): 1-27.
       doi:10.1007/s10494-012-9419-7
    .. [2] Romeo, Eva, Carlos Royo, and Antonio Monzon."Improved Explicit
       Equations for Estimation of the Friction Factor in Rough and Smooth
       Pipes." Chemical Engineering Journal 86, no. 3 (April 28, 2002): 369-74.
       doi:10.1016/S1385-8947(01)00254-6.