Before and after arguments#

The before and after Span arguments determine how much data is included in the Data (given by before) and Future data (given by after) ranges of each fold.

Argument type	Interpretation	Example
String `'all'`	Include all data before/after the scheduled time. Similar to sklearn.model_selection.TimeSeriesSplit(max_train_size=None)	Cron schedule, keeping all data before the schedule.
String `'empty'`	Used to discard datasets. Sets the edge equal the the midpoint, e.g. `after="empty"` will set `mid == end`, discarding the Future data.	No future data
`int > 0`	Include all data within N schedule periods from the scheduled time.	Removing folds with n_splits. Schedule-based before and after-data.
Anything else	Passed as-is to the `pandas.Timedelta` class. Must be positive. See Offset aliases for valid frequency strings.	Timedelta-based schedule and after arguments.