Identify US county from from latitude and longitude using Python

I am using the codes below to identify US county. The data is taken from Yelp which provides lat/lon coordinate.

id	latitude	longitude
1	40.017544	-105.283348
2	45.588906	-122.593331

import pandas
df = pandas.read_json("/Users/yelp/yelp_academic_dataset_business.json", lines=True, encoding='utf-8')

# Identify county
from geopy.geocoders import Nominatim
geolocator = Nominatim(user_agent="http")
df['county'] = geolocator.reverse(df['latitude'],df['longitude'])

The error was "TypeError: reverse() takes 2 positional arguments but 3 were given".

Solution

Nominatim.reverse takes coordinate pairs; the issue is that you are passing it pandas dataframe columns. df['latitude'] here refers to the entire column in your data, not just one value, and since geopy is independent of pandas, it doesn't support processing an entire column and instead just sees that the input isn't a valid number.

Instead, try looping through the rows:

county = []

for row in range(len(df)):
    county.append(geolocator.reverse((df['latitude'][row], df['longitude'][row])))

(Note the double brackets.)

Then, insert the column into the dataframe:

df.insert(index, 'county', county, True)

(index should be what column position you want, and the boolean value at the end indicates that duplicate values are allowed.)