Constraints that specify collections¶
Selecting in the events DataFrame
by the values in any arbitrary
Collection
is possible. The usefulness of this possibility becomes more
evident when there is a complex process behind obtaining such a collection. For
the sake of an example, let’s assume such a collection is already given.
Say we want to select all events where the player is in some specified list. We can do it like this:
import numpy as np
import pandas as pd
import xarray as xr
import xarray_events
ds = xr.Dataset(
data_vars={
'ball_trajectory': (
['frame', 'cartesian_coords'],
np.exp(np.linspace((-6, -8), (3, 2), 2450))
)
},
coords={
'frame': np.arange(1, 2451),
'cartesian_coords': ['x', 'y'],
'player_id': [2, 3, 7, 19, 20, 21, 22, 28, 34, 79]
},
attrs={'match_id': 12, 'resolution_fps': 25}
)
events = pd.DataFrame(
{
'event_type':
['pass', 'goal', 'pass', 'pass', 'pass',
'penalty', 'goal', 'pass', 'pass', 'penalty'],
'start_frame': [1, 425, 600, 945, 1100, 1280, 1890, 2020, 2300, 2390],
'end_frame': [424, 599, 944, 1099, 1279, 1889, 2019, 2299, 2389, 2450],
'player_id': [79, 79, 19, 2, 3, 2, 3, 79, 2, 79]
}
)
(
ds
.events.load(events, {'frame': ('start_frame', 'end_frame')})
.events.sel({'player_id': [2, 3]})
.events.df
)
event_type | start_frame | end_frame | player_id | |
---|---|---|---|---|
3 | pass | 945 | 1099 | 2 |
4 | pass | 1100 | 1279 | 3 |
5 | penalty | 1280 | 1889 | 2 |
6 | goal | 1890 | 2019 | 3 |
8 | pass | 2300 | 2389 | 2 |