:orphan:
:html_theme.sidebar_secondary.remove:

.. 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::
    :remove-code:
    


    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'
    )


.. tab-set::

    .. tab-item:: Method syntax
        :sync: method

        .. code:: python


            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'
            )


    .. tab-item:: Attribute syntax
        :sync: attribute

        .. code:: python


            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'
            )