"""
Scatter Matrix
--------------
An example of using a RepeatChart to construct a multi-panel scatter plot
with linked panning and zooming.
"""
# category: scatter plots
import altair as alt
from vega_datasets import data

source = data.cars()

alt.Chart(source).mark_circle().encode(
    alt.X(alt.repeat("column"), type='quantitative'),
    alt.Y(alt.repeat("row"), type='quantitative'),
    color='Origin:N'
).properties(
    width=150,
    height=150
).repeat(
    row=['Horsepower', 'Acceleration', 'Miles_per_Gallon'],
    column=['Miles_per_Gallon', 'Acceleration', 'Horsepower']
).interactive()