apply_extrema_filter#

rojak.atmosphere.regions.apply_extrema_filter(target_data, extrema_kind, latitude_dim_name='latitude', longitude_dim_name='longitude', **filter_kwargs)[source]#

Apply a spatial extrema filter to a 3D DataArray.

Applies either a maximum or minimum filter from scipy.ndimage over the latitude and longitude dimensions of a 3D DataArray, with support for Dask-backed arrays.

Parameters:

target_data (xarray.DataArray) – A 3D DataArray to apply the filter to. Must contain the specified latitude and longitude dimensions.
extrema_kind (ExtremaKind) – The type of extrema filter to apply, either ExtremaKind.MAXIMA or ExtremaKind.MINIMA.
latitude_dim_name (str) – Name of the latitude dimension in target_data. Defaults to "latitude".
longitude_dim_name (str) – Name of the longitude dimension in target_data. Defaults to "longitude".
**filter_kwargs – Additional keyword arguments passed to scipy.ndimage.maximum_filter() or scipy.ndimage.minimum_filter().

Returns:

A DataArray of the same shape and dtype as target_data with the extrema filter applied over the latitude and longitude dimensions.

Return type:

xarray.DataArray

Raises:

ValueError – If target_data is not 3D.
ValueError – If target_data does not contain the specified latitude and longitude dimensions.