:orphan:
:html_theme.sidebar_secondary.remove:

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

.. _gallery_iowa_electricity:


Iowa's Renewable Energy Boom
----------------------------
This example is a fully developed stacked chart using the sample dataset of Iowa's electricity sources.


.. altair-plot::
    :remove-code:
    


    import altair as alt
    from vega_datasets import data

    source = data.iowa_electricity()

    alt.Chart(source, title="Iowa's renewable energy boom").mark_area().encode(
        x=alt.X(
            "year:T",
            title="Year"
        ),
        y=alt.Y(
            "net_generation:Q",
            stack="normalize",
            title="Share of net generation",
            axis=alt.Axis(format=".0%"),
        ),
        color=alt.Color(
            "source:N",
            legend=alt.Legend(title="Electricity source"),
        )
    )


.. tab-set::

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

        .. code:: python


            import altair as alt
            from vega_datasets import data

            source = data.iowa_electricity()

            alt.Chart(
                source,
                title=alt.Title(
                    "Iowa's green energy boom",
                    subtitle="A growing share of the state's energy has come from renewable sources"
                )
            ).mark_area().encode(
                alt.X("year:T").title("Year"),
                alt.Y("net_generation:Q")
                    .title("Share of net generation")
                    .stack("normalize")
                    .axis(format=".0%"),
                alt.Color("source:N").title("Electricity source")
            )


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

        .. code:: python


            import altair as alt
            from vega_datasets import data

            source = data.iowa_electricity()

            alt.Chart(source, title="Iowa's renewable energy boom").mark_area().encode(
                x=alt.X(
                    "year:T",
                    title="Year"
                ),
                y=alt.Y(
                    "net_generation:Q",
                    stack="normalize",
                    title="Share of net generation",
                    axis=alt.Axis(format=".0%"),
                ),
                color=alt.Color(
                    "source:N",
                    legend=alt.Legend(title="Electricity source"),
                )
            )