Getting Easting & Northing Values from geopy

Question

I have a table full of longitude/ latitude pairs in decimal format (e.g., -41.547, 23.456). I want to display the values in "Easting and Northing"/ UTM format. Does geopy provide a way to convert from decimal to UTM? I see in the code that it will parse UTM values, but I don't see how to get them back out and the geopy Google Group has gone the way of all things.

Answer 1

I think I may have over-complicated things. All I wanted was the dms values (so 42.519540, -70.896716 becomes 42º31'10.34" N 70º53'48.18" W). You can get this by creating a geopy point object with your long and lat, then calling format(). However, as of this writing, format() is broken and requires the patch here.

Answer 2

Nope. You need to reproject your points, and geopy isn't going to do that for you.

What you need is libgdal and some Python bindings. I always use the bindings in GeoDjango, but there are other alternatives.

EDIT: It is just a mathematical formula, but it's non-trivial. There are thousands of different ways to represent the surface of the Earth. See here for a huge but incomplete list.

There are two parts to a geographic projection of the Earth-- a coordinate system and a datum. The latter is essentially a three-dimensional model of the planet. When you say you want to convert latitude/longitude points to UTM values, you're missing a couple of pieces of the puzzle.

Let's assume that your lat/long points are based on the WGS84 datum, because that's a pretty common standard for lat/long points these days. You want to convert those points to a UTM coordinate system. But to which UTM coordinate system? There are 60 of them.