netsse.analys.buoy.Fourier2spread_dist_params

netsse.analys.buoy.Fourier2spread_dist_params(a1, b1, a2, b2)

Infers the parameters of the directional spreading distribution function from the Fourier coefficients, as per Kuik et al. (1988).

Parameters:

• a1 (array_like of shape (Nf,)) – First four Fourier coefficients of the directional wave spectrum.

• b1 (array_like of shape (Nf,)) – First four Fourier coefficients of the directional wave spectrum.

• a2 (array_like of shape (Nf,)) – First four Fourier coefficients of the directional wave spectrum.

• b2 (array_like of shape (Nf,)) – First four Fourier coefficients of the directional wave spectrum.

Returns:

• alpha (array_like of shape (Nf,)) – Wave direction [rad].

• sigma (array_like of shape (Nf,)) – Directional spread [rad].

• gamma (array_like of shape (Nf,)) – Skewness of the directional distribution [-].

• delta (array_like of shape (Nf,)) – Kurtosis of the directional distribution [-].

See also

spread_dist_params2Fourier

Infers the Fourier coefficients from the parameters of the directional spreading distribution function.

References

Kuik, A. J., van Vledder, G. P., & Holthuijsen, L. H. (1988). A Method for the Routine Analysis of Pitch-and-Roll Buoy Wave Data. Journal of Physical Oceanography, 18(7), 1020–1034.

Example

>>> [alpha, sigma, gamma, delta] = Fourier2spread_dist_params(a1,b1,a2,b2)