Slightly offtopic - coordinate conversions

[Michael Lush]

On Wed, 13 Jul 2011, Peter Sergeant wrote:
> I've been playing around with Google Maps recently, and noticed that they've started using hashes of some coordinates:
>
> latlng: 52.54296 -0.308166
> hnear : 0x4877f21032e242f5:0x805cb103d71d5051
>
> latlng: 51.411586,-0.300893
> hnear : 0x47d8a00baf21de75:0x52963a5addd52a99
>
> A few attempts at working out how this was done with Perl have failed me - anyone got a better idea?

Where/why are they doing this?

I suppose it could be some kind of attempt to obfuscate the numbers in 
order to prevent 'coordinate harvesting'?

If that were the case I'd guess they could assign the coordinates to 
(unique) random numbers so there is no algorithm to crack.

--
Michael
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Michael John Lush PhD			Tel:44-1223 492626
Bioinformatician 
HUGO Gene Nomenclature Committee	Email: hgnc at genenames.org
European Bioinformatics Institute
Hinxton, Cambridge
URL: http://www.genenames.org
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