import pandas as pd
import numpy as np
from bokeh.io import show, output_notebook
from bokeh.models import GeoJSONDataSource, LinearColorMapper

import geopandas as gpd
from bokeh.palettes import Viridis6 as palette
from bokeh.plotting import figure

output_notebook()

#obtain countries shapes
world = gpd.read_file(gpd.datasets.get_path('naturalearth_lowres'))
europe = (world.loc[world['continent'] == 'Europe'])

# Normal Dataframe (non-geo)
df = pd.DataFrame(data=europe.name.str.len().values, index=europe.index, columns=['name_length'])
europe = europe.merge(df, left_index=True, right_index=True)

geo_source = GeoJSONDataSource(geojson=europe.to_json())

p = figure(title="Europe", x_range=(-30,60), y_range=(30,85))

p.patches('xs', 'ys', fill_alpha=0.7,
      fill_color={'field': 'name_length', 'transform': LinearColorMapper(palette=palette)},
      line_color='black', line_width=0.5, source=geo_source)



show(p)