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Base32 alphabet?

Open slowernet opened this issue 11 years ago • 4 comments

I'm curious how you settled on your Base32 alphabet (excluding AILO)? RFC4648 style (excluding 0189) and Crockford (excluding ILOU) seem more standard (per Wikipedia) and have active gem implementations. Might be being thick but I couldn't find a ready-made decoder for your scheme.

Thanks for your time.

slowernet avatar Nov 25 '12 03:11 slowernet

See the reference Wikipedia article: http://en.wikipedia.org/wiki/Geohash

onyxraven avatar Jul 19 '13 20:07 onyxraven

:+1: I am also curious. There doesn't seem to be any other works which exclude AILO. I first thought the wikipedia article was a typo!

joeframbach avatar Jul 08 '14 18:07 joeframbach

Yeah, the wikipedia article shows the right exclusions. Other geohash implementations look the same:

https://github.com/davetroy/geohash-js/blob/master/geohash.js = 0123456789bcdefghjkmnpqrstuvwxyz

https://github.com/lyokato/libgeohash/blob/master/src/geohash.c = 0123456789bcdefghjkmnpqrstuvwxyz

Its odd that its a different set than the standards, but at least the libraries are consistent

onyxraven avatar Jul 08 '14 19:07 onyxraven

Because: "I, l, and O conflict visually with 1 and 0 and among themselves. For A, it's just one vowel to form words."

(See here).

Well kudos to Gustavo at least for not being as puritanical as Douglas Crockford's base32 encoding.

dribnet avatar Oct 22 '14 23:10 dribnet