douglowe / bng_latlon

Converts british national grid (OSBG36) to lat lon (WGS84) and vice versa.

BNG ⇄ LatLon

Converts british national grid (OSBG36) to lat lon (WGS84) and vice versa.

Originally authored by Hannah Fry.

NEW! importable, installable, PEP8 styled, pure python and doctested

Documentation

Package includes:

• bng_to_latlon.py originally published as "Converting British National Grid to Latitude and Longitude II"
• latlon_to_bng.py originally "Converting Latitude and Longitude to British National grid"

The mathematical theory used here is set out in "A guide to coordinate systems in Great Britain" by Ordnance Survey.

Installation

Get the latest stable release from PyPi:

pip install bng_latlon

Usage

>>> from bng_to_latlon import OSGB36toWGS84
>>> OSGB36toWGS84(538890, 177320)
(51.47779538331092, -0.0014016837826672265)
...
>>> from latlon_to_bng import WGS84toOSGB36
>>> WGS84toOSGB36(51.4778, -0.0014)
(538890.1053365842, 177320.49650700082)

To Do

• common importable constants and separate util functions (Helmut transform...)
• CLI to accept filename or value pair as args