Class Choropleth

folium/features.py:1411–1717

Apply a GeoJSON overlay to the map. Plot a GeoJSON overlay on the base map. There is no requirement to bind data (passing just a GeoJSON plots a single-color overlay), but there is a data binding option to map your columnar data to different feature objects with a color scale.

class Choropleth(FeatureGroup):
    """Apply a GeoJSON overlay to the map.

    Plot a GeoJSON overlay on the base map. There is no requirement
    to bind data (passing just a GeoJSON plots a single-color overlay),
    but there is a data binding option to map your columnar data to
    different feature objects with a color scale.

    If data is passed as a Pandas DataFrame, the "columns" and "key-on"
    keywords must be included, the first to indicate which DataFrame
    columns to use, the second to indicate the layer in the GeoJSON
    on which to key the data. The 'columns' keyword does not need to be
    passed for a Pandas series.

    Colors are generated from color brewer (https://colorbrewer2.org/)
    sequential palettes. By default, linear binning is used between
    the min and the max of the values. Custom binning can be achieved
    with the `bins` parameter.

    TopoJSONs can be passed as "geo_data", but the "topojson" keyword must
    also be passed with the reference to the topojson objects to convert.
    See the topojson.feature method in the TopoJSON API reference:
    https://github.com/topojson/topojson/wiki/API-Reference


    Parameters
    ----------
    geo_data: string/object
        URL, file path, or data (json, dict, geopandas, etc) to your GeoJSON
        geometries
    data: Pandas DataFrame or Series, default None
        Data to bind to the GeoJSON.
    columns: tuple with two values, default None
        If the data is a Pandas DataFrame, the columns of data to be bound.
        Must pass column 1 as the key, and column 2 the values.
    key_on: string, default None
        Variable in the `geo_data` GeoJSON file to bind the data to. Must
        start with 'feature' and be in JavaScript objection notation.
        Ex: 'feature.id' or 'feature.properties.statename'.
    bins: int or sequence of scalars or str, default 6
        If `bins` is an int, it defines the number of equal-width
        bins between the min and the max of the values.
        If `bins` is a sequence, it directly defines the bin edges.
        For more information on this parameter, have a look at
        numpy.histogram function.
    fill_color: string, optional
        Area fill color, defaults to blue. Can pass a hex code, color name,
        or if you are binding data, one of the following color brewer palettes:
        'BuGn', 'BuPu', 'GnBu', 'OrRd', 'PuBu', 'PuBuGn', 'PuRd', 'RdPu',
        'YlGn', 'YlGnBu', 'YlOrBr', and 'YlOrRd'.
    nan_fill_color: string, default 'black'
        Area fill color for nan or missing values.
        Can pass a hex code, color name.
    fill_opacity: float, default 0.6
        Area fill opacity, range 0-1.
    nan_fill_opacity: float, default fill_opacity
        Area fill opacity for nan or missing values, range 0-1.
    line_color: string, default 'black'