Geohash: Difference between revisions
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→{{header|J}}: slight efficiency gain and an observation about rounding
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geohash=: {{
bits=.
x{.gdigits{~_5 #.\,|:|.(bits#2)#:<.(2^bits)*(y+90 180)%180 360
}}</syntaxhighlight>
Note that the test cases suggest that rounding should never be used when generating a geohash. This guarantees that a short geohash is always a prefix of a longer geohash for the same location.
<syntaxhighlight lang=J> 2 geohash 51.433718 _0.214126
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