2

To learn geopandas, I'm trying to layer US cities (raw json file) over a world map provided by Geopandas. With the same CRS, the US cities are showing up in the wrong place (picture below). If I used the cities dataset (provided by Geopandas.datasets), it works fine.

import matplotlib.pyplot as plt
from geopandas import GeoDataFrame
from shapely.geometry import Point
import pandas as pd

world = world[(world.pop_est>0) & (world.name!="Antarctica")]
world['gdp_per_cap'] = world.gdp_md_est / world.pop_est

# US Cities from Raw JSON File
url = 'https://gist.githubusercontent.com/Miserlou/c5cd8364bf9b2420bb29/raw/2bf258763cdddd704f8ffd3ea9a3e81d25e2c6f6/cities.json'
cities_df = pd.read_json(url)
geometry = [Point(xy) for xy in zip(cities_df['latitude'], cities_df['longitude'])]
cities_gpd = GeoDataFrame(cities_df, crs=world.crs, geometry=geometry)

cities_gpd.crs, world.crs
# Ouputs ({'init': 'epsg:4326'}, {'init': 'epsg:4326'})


fig, ax = plt.subplots(figsize=(10, 5))
ax.set_aspect('equal')
world.plot(ax=ax, column='gdp_per_cap', cmap='OrRd', scheme='quantiles')
cities_gpd.plot(ax=ax, marker='o', color='green', markersize=16)
plt.show()

Map Image enter image description here

6

The problem appears to be here:

geometry = [Point(xy) for xy in zip(cities_df['latitude'], cities_df['longitude'])]

Latitude is y, longitude is x. Just swap the keys.

You can see the transposition in the image below.

geo flipped

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