reduce

earthkit.transforms.reduce(dataarray: Dataset | DataArray, *_args, **kwargs)[source]

Reduce an xarray.dataarray or xarray.dataset using a specified how method.

With the option to apply weights either directly or using a specified weights method.

Parameters:
  • dataarray (xarray.DataArray or xarray.Dataset) – Data object to reduce

  • how (str or callable) – Method used to reduce data. Default=’mean’, which will implement the xarray in-built mean. If string, it must be an in-built xarray reduce method, a earthkit how method or any numpy method. In the case of duplicate names, method selection is first in the order: xarray, earthkit, numpy. Otherwise it can be any function which can be called in the form f(x, axis=axis, **kwargs) to return the result of reducing an xp.ndarray over an integer valued axis

  • weights (str) – Choose a recognised method to apply weighting. Currently available methods are; ‘latitude’

  • how_label (str) – Label to append to the name of the variable in the reduced object

  • how_dropna (str or None) – Choose how to drop nan values. Default is None and na values are preserved. Options are ‘any’ and ‘all’.

  • **kwargs – kwargs recognised by the how :func: reduce

Returns:

A data array with reduced dimensions removed.

Return type:

xarray.DataArray or xarray.Dataset