Displaying customized geojson with both 'Polygon' and 'Point' features using plotly.express

Dash Python
1

Hi,

I’m using plotly.express to display a customized (built from scratch) geojson file with several ‘Polygon’ features.
The customized geojson has the usual structure for the features,
‘geometry’: {‘type’: ‘Polygon’, ‘coordinates’: [coords]}}),
and everything works just fine with plotly.express.choropleth() and all the features show up as expected.

However, if I try to add points to the geojson as in
‘geometry’: {‘type’: ‘Point’, ‘coordinates’: [coords]}}),
they do not show up.

I know that there is a method plotly.express.scatter_geo(), but I assume this would only serve to plot the points.

So the question is: How do I mix customized geojson ‘Polygon’ and ‘Point’ features in a single figure? Do I have to “make” small polygons (circles, squares, or triangles) just to show the points? I could do that, but it seems very inefficient.

Thank you.

2

You could try Dash Leaflet. It supports both Polygons and Points. Here is an example,

3

You can also add arbitrary GeoJSON layers & features to plotly maps. See the GeoJSON Layers example here: https://plotly.com/python/filled-area-on-mapbox/#geojson-layers. Note that they won’t have the same nice hover features as the data-driven options.

5

Thank you so much. Although I have worked with leaflet in R and got good results, I really don’t want to go that direction this time. I’m looking for something that feels more ‘plotlyonic’ this time.

6

Thank you for the suggestion. I’ve tried the sample code on a triangle, inside the callback, just to see what I would get, before attempting with ‘Points’. The polygons in the geojson show up as previously and it doesn’t throw any error, but the test polygon doesn’t show up.

fig1 = px.choropleth(new_descriptor, geojson=new_map1, featureidkey='properties.NAME',
                     locations='NAME', projection='mercator', hover_data=['NAME'],
                     color=tipo_gestor,
                     color_discrete_sequence=['rgba(220,220,220,0.2)',
                                              'rgba(250,165,47,0.6)', 'rgba(62,129,19,0.6)',
                                              'rgba(250,165,47,0.8)', 'rgba(62,129,19,0.8)'])
fig1.update_traces(dict(showscale=False, coloraxis=None))
fig1.update_geos(fitbounds='locations', visible=False)  # don't print world map
fig1.update_layout(
    autosize=True, showlegend=False,
    mapbox={
        'layers': [{
            'source': {
                'type': "FeatureCollection",
                'features': [{
                    'type': "Feature",
                    'geometry': {
                        'type': "Polygon",
                        'coordinates': [[[-9.0, 39.5], [-8.5, 39.5], [-8.7,39.0]]]
                    }
                }]
            },
            'type': "fill", 'below': "traces", 'color': "royalblue"}
        ]},
    margin={"r": 0, "t": 0, "l": 0, "b": 0}
)
return fig1