wavespectra.core.npstats.jonswap

wavespectra.core.npstats.jonswap(freq, fpeak, hsig, gamma=3.3, alpha=0.0081, sigma_a=0.07, sigma_b=0.09)

Jonswap frequency spectrum for developing seas (Hasselmann et al., 1973).

Args:

• freq (1darray): Frequency array (Hz).

• fpeak (float): Peak wave frequency (Hz).

• hsig (float): Significant wave height (m), if provided the Jonswap spectra are scaled so that \(4\sqrt{m_0} = hs\).

• gamma (float): Peak enhancement parameter.

• alpha (float): Phillip’s fetch-dependent scaling coefficient.

• sigma_a (float): width of the peak enhancement parameter for f <= fp.

• sigma_b (float): width of the peak enhancement parameter for f > fp.

Returns:

• efth (SpecArray): Jonswap spectrum E(f) (m2s).

Note:

• This function is a numpy version of the wavespectra.frequency.jonswap function and is primarily defined for spectral fitting.

• If hs is provided than the scaling parameter alpha becomes irrelevant.