monad.targets.slice_time_window

monad.targets.slice_time_window(events, start, end)

Restricts the events to a desired time range.

This function takes an explicit start and end timestamp and trims the event streams passed into your target function to that interval.

Semantics:

• Half-open interval – [start, end) includes start, excludes end.
• Empty/out-of-range windows – safe, returns empty events.
• Supported types – numeric Unix timestamps (seconds) or datetimes converted to timestamps.
• Time zones – always use UTC.
• Multiple streams – each stream is sliced independently.

from datetime import datetime
from monad.targets import slice_time_window

def target_fn(_history: Events, future: Events, _entity: Attributes, _ctx: Dict) -> np.ndarray:
  start = datetime(2020, 3, 15).timestamp()  # inclusive
  end   = datetime(2020, 4, 5).timestamp()   # exclusive  
  future_constrained = next_n_hours(events=future, start=start, end=end)
  ...

Edge Cases:

• start ≥ end → returns empty events.
• Window outside range → empty events.
• Duplicate timestamps → all values with start ≤ t < end are included.

Best Practices:

• Convert datetimes to UTC numeric timestamps before slicing.
• Apply slicing at the target function input level; do not preprocess upstream.
• Use with care when training — slicing reduces available samples and can affect variance.

Interactions :

• Target functions – slicing acts as a pre-filter before your computations.
• Temporal splits – can be combined with history/future splits to constrain evaluation periods.\
• Date handling improvements – supports numeric date formats and correct boundary handling.

Troubleshooting:

• Empty slices → verify timestamp units (seconds vs. ms) and overlap.
• Boundary issues → remember end is exclusive.

events : Events
Events to filter.

start : float
The timestamp indicating the inclusive lower bound of the time window for events to be considered after applying the filter.

end: float

The timestamp indicating the exclusive upper bound of the time window for events to be considered after applying the filter.

Events restricted to the chosen time range.