如何编辑 geojson 文件中的坐标值？

Question

I am trying to map a geojson file (A map of Alaska precincts, downloaded from the division of elections and then converted online to geojson) onto a choropleth map using folium, the problem is the coordinates are in 7-digit numbers like this:

[ -16624764.227, 8465801.1497 ]

I read on a similar post that this was most likely a US coordinate system like UTM or State Plane, and recommended using an API to reproject it. Is it also possible to access the coordinates directly such as with geopandas and divide them by 100000?

Answer 1

The data is most likely in a specific cartographic projection . You don't just want to divide by 100k - the data will likely have nonlinear transformations which have a different effect on the position depending on the location. See the GeoPandas docs on working with projections .

If the CRS of the data is correctly encoded, you can re-project the dataframe into lat/lons (eg WGS84, which has the EPSG Code 4326) using geopandas.GeoDataFrame.to_crs , eg:

df_latlon = df.to_crs("epsg:4326")