Base32 alphabet?

[slowernet]

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.

[onyxraven]

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

[joeframbach]

👍 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!

[onyxraven]

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

[dribnet]

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.