WINDTRANS is the jOceans module of jLab.

 WINDTRANS  Ekman-like transfer-functions for the wind-driven response.
    G=WINDTRANS(OMEGA,Z,FC,DELTA,MU,H) returns the no-slip transfer 
    function for the wind-driven currents evaluated at frequencies OMEGA
    and at depths Z.  G will have LENGTH(OMEGA) rows and LENGTH(Z) columns.
    Here FC is the local Coriolis frequency, DELTA is the Ekman depth.
    MU is the Madsen depth, and H is the boundary layer depth.
    The units of these quantitites are important.  For consistency with 
    other routines, OMEGA and FC are in radians per day, while Z, DELTA,
    MU, and H are all in meters.  The units of G are then m^2 s / kg.
    WINDTRANS(...,'free') instead returns the free slip transfer function.
    For details on the expressions implemented by this function, see
         Lilly, J. M. and S. Elipot (2021). A unifying perspective on 
             transfer function solutions to the unsteady Ekman problem. 
             Fluids, 6 (2): 85, 1--36. 
    Special forms
    By default WINDTRANS uses the general transfer function.  WINDTRANS 
    will also employ limiting expressions for special cases, as follows.
        H = Inf                --  Mixed Ekman / Madsen solution
        H = Inf, MU = 0        --  Ekman solution
        H = Inf, DELTA = 0     --  Madsen solution
        MU = 0                 --  Finite-layer Ekman solution
        DELTA = 0              --  Finite-layer Madsen solution
    These have to be coded separately because the full solution is singular
    in these cases.
    Computational options
    When computed over a wide range of parameter space, the transfer
    function tends to be encounter numerical overflow when the arguments to
    Bessel functions become large, causing its computation to fail.
    To avoid this problems, by default WINDTRANS switches to using a highly
    accurate thirty-term expansion about the large-argument exponential 
    behavior of the Bessel functions when their arguments exceed 10^2.9. 
    Two other options are available, primarily for testing purposes. Both
    of these other algorithms lead to artifacts and are not recommended.
    WINDTRANS(...'far',...) switches instead to use the (inferior) one-term 
    expansion, also known as the far-inertial limit.
    WINDTRANS(...,'general',...) uses the general formula with no switch.
    Note that these options only apply to no-slip solution.  The free-slip
    solution, which is not deemed to be physically relevant, is only
    computed with the general formula.
    For details on these algorithms, see Lilly and Elipot (2021).
    'windtrans --t' runs a some tests.
    Usage: G=windtrans(omega,z,fc,delta,mu,h);
    This is part of JLAB --- type 'help jlab' for more information
    (C) 2019--2021 J.M. Lilly --- type 'help jlab_license' for details

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