wavespectra.partition.partition.Partition.ptm3

Partition.ptm3(parts=3, smooth=False, freq_window=3, dir_window=3, ihmax=100)

PTM3 watershed partitioning with no wind-sea or swell classification.

PTM3 does not classify the topographic partitions into wind-sea or swell - it simply orders them by wave height. This approach is useful for producing data for spectral reconstruction applications using a limited number of partitions, where the classification of the partition as wind-sea or swell is less important than the proportion of overall spectral energy each partition represents. In addition, this method does not require wind and water depth information and can be used with any spectral dataset.

Args:

• parts (int): Number of partitions to keep.

• smooth (bool): Compute watershed boundaries from smoothed spectra as described in Portilla et al., 2009.

• freq_window (int): Size of running window along freq for smoothing spectra.

• dir_window (int): Size of running window along dir for smoothing spectra.

• ihmax (int): Number of discrete spectral levels in WW3 Watershed code.

Returns:

• dspart (xr.Dataset): Partitioned spectra with extra part dimension defining watershed partitions sorted by descending order of Hs.

References:

• Portilla et al. (2009).

• Tracy et al. (2007).

• Vincent et al. (1991).

• WW3 documentation (NOAA-EMC/WW3).