Superposing two plots with Geopandas, with non fill colours in one of them

Question

I would like to plot a map of the edges of the French departments, and the heat maps at the lower scale of the French IRIS. I read both shapefiles using GeoPandas.

And now

dep.plot(color="white", edgecolor='black')

and

iris.plot(column = 'ratio',cmap = 'Purples',ax=ax)

I would like to visualise the black edge colours of the departments on the IRIS plot, but when I try this

fig, ax = plt.subplots(figsize = (20,16)) 
df.plot(column = 'ratio',cmap = 'Purples',ax=ax)
dep.plot(color=None,edgecolor='k',linewidth = 4,ax=ax)

the first figure does not appear, and is hid by the second. I have tried to use alpha, to put the colour as None, but nothing seems to work.

Any help?

Answer 1

You can set facecolor="none" and edgecolor="black"

import geopandas as gpd
df = gpd.read_file(r"/home/bera/Desktop/GIStest/France_etc.geojson")
ax = df.plot(column="NAME", cmap="rainbow", figsize=(20, 30))
df.plot(ax=ax, facecolor="none", edgecolor="black", linewidth=5)

Answer 2

Use facecolor='none' to plot an unfilled face. None causes default behaviour, 'none' does not fill.