2022-05-23 00:16:32 +04:00

32 lines
968 B
Python

"""
Top-K plot with Others
----------------------
This example shows how to use aggregate, window, and calculate transfromations
to display the top-k directors by average worldwide gross while grouping the
remaining directors as 'All Others'.
"""
# category: case studies
import altair as alt
from vega_datasets import data
source = data.movies.url
alt.Chart(source).mark_bar().encode(
x=alt.X("aggregate_gross:Q", aggregate="mean", title=None),
y=alt.Y(
"ranked_director:N",
sort=alt.Sort(op="mean", field="aggregate_gross", order="descending"),
title=None,
),
).transform_aggregate(
aggregate_gross='mean(Worldwide_Gross)',
groupby=["Director"],
).transform_window(
rank='row_number()',
sort=[alt.SortField("aggregate_gross", order="descending")],
).transform_calculate(
ranked_director="datum.rank < 10 ? datum.Director : 'All Others'"
).properties(
title="Top Directors by Average Worldwide Gross",
)