geopy distance calculation pitfall
10th of December 2007
Geopy is a great little Python library for working with geocoding and distances using various online services such as Google's geocoder API.
Today I spent nearly half an hour trying to debug what was going on with my web application since I was getting this strange error:
AttributeError: 'VincentyDistance' object has no attribute '_kilometers'
To debug it I wrapped the calls to geopy.distance.distance in various try-and-except statements to see what was going on and run these queries in a separate file. After a while I discovered that was what so special about the coordinates I fed it was that the coordinates where the same. Now my wrapping function looks like this instead:
from geopy import distance as geopy_distance
def geocode_distance((x1, y1), (x2, y2), unit='km'):
if (x1, y1) == (x2, y2):
return 0
d = geopy_distance.distance((x1, y1), (x2, y2))
if unit == 'miles':
return d.miles
else:
return d.kilometers
def geocode_distance((x1, y1), (x2, y2), unit='km'):
if (x1, y1) == (x2, y2):
return 0
d = geopy_distance.distance((x1, y1), (x2, y2))
if unit == 'miles':
return d.miles
else:
return d.kilometers
Here's the mailing list thread about the very same issue
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