vp.features.since_last

Seconds since the last event of a kind, and of any kind (catalog/since_last.viv).

Part of the distribution vipyr; it runs from a checkout of the repository. Planned on PyPI as pip install vipyr.

Signature

vp.features.since_last(df=None, n=500, kind='purchase')

Parameters

df : pandas.DataFrame, default None

The event table, rows in any order; None makes a synthetic one of n rows.

n : int, default 500

Rows of the synthetic table when df is None. Range: >= 1.

kind : str, default 'purchase'

Returns

A frozen SinceLastResult. Iterating it gives the fields below in order; it also has params, tests, log and check().

frame : pandas.DataFrame

The features, one row per input row, in the input's order and index: .

Raises

TypeError

An argument of the wrong type, or an unknown keyword.

vipyr.VivBuildError

An ImportError: no C compiler, or the program's C does not build.

Examples

import vipyr as vp
r = vp.features.since_last()                # a synthetic table; pass df= for yours
print(r.frame.head())
assert r.check()

   secs_since_hit  secs_since_prev
0             NaN              NaN
1             NaN          52443.0
2             NaN          54821.0
3             NaN          12638.0
4             NaN         159535.0

Each example ran as written when these pages were generated, and the output shown is what it printed.

Checked against

Reference

catalog.since_last_reference: a pandas groupby().apply() with a Python loop per row, equal bit for bit; vipyr.check_point_in_time: no feature reads a row after its own time

Source

• Viv: catalog/since_last.viv
• Viv: catalog/catalog.py
• The defs it reaches and the calls between them: map of the code