3.0 KiB
These3Words
Address any 3meter x 3meter square on earth with a unique three word name.
Inspired by http://what3words.com/
example
>>> import thesethreewords as these
# the home of particle physics
>>> CERN = (46.232355, 6.055419)
>>> three = these.three_words(CERN)
>>> print three
'spitting-ripple-fontanel'
>>> these.decode(three)
(46.232335567474365, 6.055419445037842)
Check out where this is on google maps.
requirements
You need to install the geohash and bottle libraries:
$ pip install geohash
$ pip install bottle
six words
There are a lot of 3x3m squares on the earth's surface. To encode them in only three words requires a long wordlist, as a result some fairly obscure words get on it. If you can live with having to remember six words the wordlist is much shorter. The six word wordlist comes from the amazing humanhash library. Words were chosen to maximise clarity in human communication, they should be more familiar than the words on the three wordlist:
>>> six = these.six_words(CERN)
>>> print six
'spaghetti-carolina-kentucky-oscar-iowa-table'
>>> these.decode(six)
(46.232335567474365, 6.055419445037842)
how it works
Each latitude/longitude pair is converted to a nine character geohash. This provides about 3meter resolution at all latitudes. The geohash is then converted to an integer which is encoded as a string of words.
The wordlist used to encode the geohash into just
three words uses your local computers dictionary. Some
attempts are made to remove really obscure words but
it could be better. You need to use the same wordlist
when encoding and decoding a these-3-words hash.
The these-3-words hash shares the
property of a geohash that nearby locations share
have similar these-3-words hashes
>>> other_CERN_site = (46.256811, 6.056792)
>>> six = these.six_words(other_CERN_site)
>>> print six
'spaghetti-carolina-kentucky-utah-seventeen-neptune'
>>> these.decode(six)
(46.256797313690186, 6.056792736053467)
The other CERN site is here.
webservice
The file server.py provides a tiny webservice that allows to display a
location given by three words on a Google Maps map.
The server requires bottle.py to be installed. It can be run
locally by typing ./server.py or python server.py respectively.