.. This document is auto-generated by the altair-gallery extension. Do not modify directly.

.. _gallery_grouped_bar_chart_with_error_bars:


Grouped Bar Chart with Error Bars
---------------------------------
This example shows a grouped bar chart with error bars.


.. altair-plot::
    :code-below:

    
    import altair as alt
    from vega_datasets import data

    source = data.barley()

    bars = alt.Chart().mark_bar().encode(
        x='year:O',
        y=alt.Y('mean(yield):Q', title='Mean Yield'),
        color='year:N',
    )

    error_bars = alt.Chart().mark_errorbar(extent='ci').encode(
        x='year:O',
        y='yield:Q'
    )

    alt.layer(bars, error_bars, data=source).facet(
        column='site:N'
    )


.. toctree::
   :hidden: