stglib.core.waves.define_cutoff

stglib.core.waves.define_cutoff(f, Pxx, Kp, noise=0.9)[source]

Define cutoff based on Jones & Monismith (2007) values for the noise floor cutoff (12*noise), f_peak cutoff (1.1*f_peak), along with a cutoff based on 0.1 K_p (pressure transfer function)

Parameters:

  • f (array_like) – Frequencies

  • Pxx (array_like) – Untransformed pressure spectra

  • Kp (array_like) – Pressure transfer function

  • noise (float, optional) – Fractional frequency above which we consider data to be noise. Default 0.9 (i.e. top 10% of frequencies considered noise)

Returns:

  • tailind (int) – Index for where to start applying the f^-4 tail

  • noisecutind (int) – Index for noise cutoff

  • fpeakcutind (int) – Index for f_peak cutoff

  • Kpcutind (int) – Index for the K_p cutoff

References

Jones, N. L., & Monismith, S. G. (2007). Measuring short-period wind waves in a tidally forced environment with a subsurface pressure gauge. Limnology and Oceanography: Methods, 5, 317–327. http://doi.org/10.4319/lom.2007.5.317