Slow Rendering Plotly Expess Choropleth Map

📊 Plotly Python
1

Hello,

Any idea how to optimize the code below so the map will render faster? It takes at least 30s for the map to show. Other graphs are okay.

ct_geo.json is about 4MB. I have it in streamlit.

def load_geo_json():
    file_contents = open('assets/ct_geo.json', 'r')
    return json.loads(file_contents.read())

zipcodes = load_geo_json()

fig = px.choropleth(df_active_num_dynamic, 
                                geojson=zipcodes, 
                                locations='postalcode', 
                                color='Active',
                                color_continuous_scale="Sunset",
                                range_color=(0, df_active_num_dynamic['Active'].max()),
                                featureidkey="properties.ZCTA5CE10",
                                scope="usa",
                                custom_data=["postalcode", "Active", "city",]
                                # labels={'Active':'# of Active Listings'}
                                )

            fig.update_geos(fitbounds="locations")
            fig.update_traces(
                hovertemplate="<br>".join([
                    "Zip Code: %{customdata[0]}",
                    "# of Actives: %{customdata[1]}",
                    "City: %{customdata[2]}",
                ])
            )

            fig.update_layout(height=500, margin={"r":0,"t":0,"l":0,"b":0})
            st.plotly_chart(fig, use_container_width=True)
2

streamlit has a cache function. It may take longer the first time, but the time will be greatly reduced the next time. See this for details.
https://docs.streamlit.io/library/advanced-features/caching

3

Thanks! my map is dynamic so every time the user changes the drop down for the map, it will refresh the whole page and the cache function doesn’t help. I am more wondering if the map itself has some parameters or some sort to speed up the processing time. Thank you