:orphan:
:html_theme.sidebar_secondary.remove:

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

.. _gallery_bump_chart:


Bump Chart
----------
This example shows a bump chart.  The data is first grouped into six-month
intervals using pandas. The ranks are computed by Altair using a 
window transform.


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



    import altair as alt
    from vega_datasets import data
    import pandas as pd

    stocks = data.stocks()
    source = stocks.groupby([pd.Grouper(key="date", freq="6M"),"symbol"]).mean().reset_index()

    alt.Chart(source).mark_line(point = True).encode(
        x = alt.X("date:O", timeUnit="yearmonth", title="date"),
        y="rank:O",
        color=alt.Color("symbol:N")
    ).transform_window(
        rank="rank()",
        sort=[alt.SortField("price", order="descending")],
        groupby=["date"]
    ).properties(
        title="Bump Chart for Stock Prices",
        width=600,
        height=150,
    )

.. tab-set::

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

        .. code:: python



            import altair as alt
            from vega_datasets import data
            import pandas as pd

            stocks = data.stocks()
            source = stocks.groupby([pd.Grouper(key="date", freq="6M"),"symbol"]).mean().reset_index()

            alt.Chart(source).mark_line(point=True).encode(
                x=alt.X("date:O").timeUnit("yearmonth").title("date"),
                y="rank:O",
                color=alt.Color("symbol:N")
            ).transform_window(
                rank="rank()",
                sort=[alt.SortField("price", order="descending")],
                groupby=["date"]
            ).properties(
                title="Bump Chart for Stock Prices",
                width=600,
                height=150,
            )


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

        .. code:: python



            import altair as alt
            from vega_datasets import data
            import pandas as pd

            stocks = data.stocks()
            source = stocks.groupby([pd.Grouper(key="date", freq="6M"),"symbol"]).mean().reset_index()

            alt.Chart(source).mark_line(point = True).encode(
                x = alt.X("date:O", timeUnit="yearmonth", title="date"),
                y="rank:O",
                color=alt.Color("symbol:N")
            ).transform_window(
                rank="rank()",
                sort=[alt.SortField("price", order="descending")],
                groupby=["date"]
            ).properties(
                title="Bump Chart for Stock Prices",
                width=600,
                height=150,
            )