Putting values over each country in choropleth maps in Python

Question

I'm trying to plot a map for africa so the final result looks like the following:

Which is each country colored and have a word / value over it.

So, I tried to use choropleth from plotly.express and that's my code:

CSV file:

country   capital   longitude   latitude
Nigeria   Bamako       -8        12.63
Mali      Abuja       7.53        8.93

import geopandas as gpd
import plotly.express as px
import pandas as pd

df = pd.read_csv(dirname)

df_geo = gpd.GeoDataFrame(df, geometry=gpd.points_from_xy(df.longitude, df.latitude))

world_data = gpd.read_file(gpd.datasets.get_path('naturalearth_lowres'))

f = px.choropleth(df, locationmode='country names', locations=df['country'],scope='africa', color=df['country'])
f.show()

and the final result looks like this:

The colors working good but any idea how I can put some values or a word over the colored countries?

Answer 1

Since you didn't provide the sample data from your csv, assuming it's the data you like to use to annotate the maps. In this example I use the country short names as the text which can be added by plotly.go.scattergeo.

import geopandas as gpd
import plotly.express as px
import json

world_data = gpd.read_file(gpd.datasets.get_path('naturalearth_lowres'))
africa  = world_data[world_data.continent=='Africa']
africa_json = json.loads(africa.to_json())
f = px.choropleth(africa,
                  geojson=africa_json,
                  featureidkey='properties.name',
                  locations='name',
                  color='name')

## Add labels on countries
f.add_scattergeo(
    geojson=africa_json,
    locations=africa['name'],
    featureidkey='properties.name',
    text=africa['iso_a3'],
    mode='text',
)
f.update_geos(fitbounds='locations')