OverviewΒΆ

Altair is a declarative statistical visualization library for Python, based on Vega and Vega-Lite.

Altair offers a powerful and concise visualization grammar that enbles you to build a wide range of statistical visualizations quickly. Here is an example of using the Altair API to quickly visualize a dataset with an interactive scatter plot:

import altair as alt

# load a simple dataset as a pandas DataFrame
from vega_datasets import data
cars = data.cars()

alt.Chart(cars).mark_point().encode(
    x='Horsepower',
    y='Miles_per_Gallon',
    color='Origin',
).interactive()

The key idea is that you are declaring links between data columns and visual encoding channels, such as the x-axis, y-axis, color, etc. The rest of the plot details are handled automatically. Building on this declarative plotting idea, a surprising range of simple to sophisticated plots and visualizations can be created using a relatively concise grammar.