对于通过 pandas 数据帧的纬度和经度循环

Question

So I have a dataframe with two columns cities and counties that has some cities from Maryland USA. I am trying to loop through to get the latitude and longitude coordinates for each city using the following code:

from geopy.geocoders import Nominatim
latitude=[]
longitude=[]
for city in df["City"]:

    address = city + ', MD'

    geolocator = Nominatim(user_agent="tor_explorer")
    location = geolocator.geocode(address)
    latitude = location.latitude
    longitude = location.longitude
df['latitude']=latitude
df['longitude']=longitude

But when I print latitude or longitude there's only one value in the list so when I put it into the dataframe it just repeats the same latitude and longitude for every city.

Answer 1

You are assigning the last value the for loop takes, so try to append each value of the for loop:

latitude=[]
longitude=[]
for city in df["City"]:

    address = city + ', MD'

    geolocator = Nominatim(user_agent="tor_explorer")
    location = geolocator.geocode(address)
    latitude.append(location.latitude)
    longitude.append(location.longitude)
df['latitude']=latitude
df['longitude']=longitude