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10:10 Code FAQ

Yesterday's post about my 10:10 code idea resulted in quite a lot of comments. Here are answers to common questions.

1. What about using both lower- and upper-case?

I could but that makes it a lot more fiddly to enter on a device since you are having to change between upper and lowercase. Using just uppercase is consistent and easy to enter (think most GPS device keyboards).

2. Take into account that at higher latitudes, longitude need not be encoded as accurately.

I agree that it would be possible to project onto a map projection to change this, and it would provide some improvement. The advantage of the system as proposed is simplicity. It gives gives 11.1m of accuracy at the equator and 7.1m of accuracy at 50 degrees of latitude (either north of south).

3. Don't combine latitude and longitude. Keep them separate, with a space in between.

The 10:10 code isn't meant to be interpreted by a human, it has a specific purpose for entry into mapping devices. There are plenty of other codes that allow comparison easily.

4. Hey Nice Idea man.. But I propose either to use alphabets only or remove some confusing (look a likes )LIke: (1 and I,l),(0,o,O),(B,8),(b,6)

The solution to this is mostly not to change the alphabet. As I originally wrote the solution is for systems that accept these codes to be permissive. For example, I don't have L or I in the alphabet, I also don't have 0 and O. So a system can interpret user input. Example: user enters O when they meant 0. The system just transforms it to 0. I agree that B and 8 might cause some confusion, but there is the check digit in there to spot those errors.

5. Do you have decoding code?

Yes, I will release this shortly in a nice, tested version that everyone can play with.

6. What are the licensing conditions?

The idea, the source code, the algorithm are all placed into the public domain. I would prefer that this get adopted widely to make everyone's lives better. I reserve the right to trademark "10:10 Code". The greatest reward for me would be people saying: "Ah, so you're the guy who invented that".

7. Why restrict yourself to 10 digits?

The idea is that 10 digits are a fairly common quantity for people to type. For example, a standard US phone number is 10 digits (e.g. (415) 555 1234). I write the 10:10 codes in a 3:3:4 form, e.g. R5T 3ED J9VW.


Unknown said…
I must say I agree with you on most points, except on point 3. If this was to be adopted internationally (would be very awesome), I think it being somewhat human readable would be a big plus.

I live in the Netherlands and our zip codes are very well structured in areas and subareas, this makes it easy to determine where a certain zip code might be located. You should think about this, because if it can be human readable, why not?
Unknown said…
Did you release a decoder?

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