# xarray.core.groupby.DatasetGroupBy.map

`DatasetGroupBy.``map`(func, args=(), shortcut=None, **kwargs)

  Apply a function to each Dataset in the group and concatenate them together into a new Dataset.

  func is called like func(ds, *args, **kwargs) for each dataset ds in this group.

  Apply uses heuristics (like pandas.GroupBy.apply) to figure out how to stack together the datasets. The rule is:

  1. If the dimension along which the group coordinate is defined is still in the first grouped item after applying func, then stack over this dimension.
  2. Otherwise, stack over the new dimension given by name of this grouping (the argument to the groupby function).

  Parameters:

  - func (function) – Callable to apply to each sub-dataset.
  - args (tuple, optional) – Positional arguments to pass to func.
  - **kwargs – Used to call func(ds, **kwargs) for each sub-dataset ar.

  Returns: | applied – The result of splitting, applying and combining this dataset.
  Return type: | Dataset or DataArray