temporian.EventSet.since_last

since_last(
    steps: int = 1,
    sampling: Optional[EventSetOrNode] = None,
) -> EventSetOrNode

Computes the amount of time since the last previous timestamp in an EventSet.

If a number of steps is provided, compute elapsed time after moving back that number of previous events.

Basic example with 1 and 2 steps

>>> a = tp.event_set(timestamps=[1, 5, 8, 8, 9])

>>> # Default: time since previous event
>>> b = a.since_last()
>>> b
indexes: ...
        timestamps: [1. 5. 8. 8. 9.]
        'since_last': [nan  4.  3.  0.  1.]
...

>>> # Time since 2 previous events
>>> b = a.since_last(steps=2)
>>> b
indexes: ...
        timestamps: [1. 5. 8. 8. 9.]
        'since_last': [nan  nan  7.  3.  1.]
...

If sampling is provided, the output will correspond to the time elapsed between each timestamp in sampling and the latest previous or equal timestamp in the input.

Example with sampling

>>> a = tp.event_set(timestamps=[1, 4, 5, 7])
>>> b = tp.event_set(timestamps=[-1, 2, 4, 6, 10])

>>> # Time elapsed between each sampling event
>>> # and the latest previous event in a
>>> c = a.since_last(sampling=b)
>>> c
indexes: ...
        timestamps: [-1. 2. 4. 6. 10.]
        'since_last': [nan  1.  0.  1. 3.]
...

>>> # 2 steps with sampling
>>> c = a.since_last(steps=2, sampling=b)
>>> c
indexes: ...
        timestamps: [-1. 2. 4. 6. 10.]
        'since_last': [nan  nan  3.  2. 5.]
...

Parameters:

Name	Type	Description	Default
steps	int	Number of previous events to compute elapsed time with.	1
sampling	Optional[EventSetOrNode]	EventSet to use the sampling of.	None

Returns:

Type	Description
EventSetOrNode	Resulting EventSet, with same sampling as sampling if provided, or as the input if not.