How wide is the 4-bit geohash encoding?

I Baidu a bit, the 5-digit geohash probably can represent 10 square kilometers. So what is the size of the 4-bit geohash that might be?

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I Baidu a bit, the 5-digit geohash probably can represent 10 square kilometers. So what is the size of the 4-bit geohash that might be?

Http://www.cnblogs.com/LBSer/p/3310455.html
I believe you have read this article, the calculation of the scope of the method is very simple, is the last approximation of your latitude and longitude area is good. 4 digits according to the article it should be a 20-bit binary, with 10 approximations by latitude, as shown in the article table. The latitude and longitude are converted according to the range of the last approximation:

纬度：39.9024375 - 39.726625 = 0.1758125 经度：116.3671875 - 116.015625 = 0.3515625

That is, the minimum can be expressed in such a large area of the range, according to the original wiki address know the latitude and longitude of the equivalent kilometer, the final calculation of the area is about 60 square kilometers look like? The principle is probably this, but the math is more urgent, the final calculation of their own results a little uncertain-. -....

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