def Barati(Re):
    r'''Calculates drag coefficient of a smooth sphere using the method in
    [1]_.

    .. math::
        C_D = 5.4856\times10^9\tanh(4.3774\times10^{-9}/Re)
        + 0.0709\tanh(700.6574/Re) + 0.3894\tanh(74.1539/Re)
        - 0.1198\tanh(7429.0843/Re) + 1.7174\tanh[9.9851/(Re+2.3384)] + 0.4744

    Parameters
    ----------
    Re : float
        Particle Reynolds number of the sphere using the surrounding fluid
        density and viscosity, [-]

    Returns
    -------
    Cd : float
        Drag coefficient [-]

    Notes
    -----
    Range is Re <= 2E5

    Examples
    --------
    Matching example in [1]_, in a table of calculated values.

    >>> Barati(200.)
    0.7682237950389874

    References
    ----------
    .. [1] Barati, Reza, Seyed Ali Akbar Salehi Neyshabouri, and Goodarz
       Ahmadi. "Development of Empirical Models with High Accuracy for
       Estimation of Drag Coefficient of Flow around a Smooth Sphere: An
       Evolutionary Approach." Powder Technology 257 (May 2014): 11-19.
       doi:10.1016/j.powtec.2014.02.045.
    '''
    Cd = (5.4856E9*tanh(4.3774E-9/Re) + 0.0709*tanh(700.6574/Re)
    + 0.3894*tanh(74.1539/Re) - 0.1198*tanh(7429.0843/Re)
    + 1.7174*tanh(9.9851/(Re+2.3384)) + 0.4744)
    return Cd