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bradabrams / GeekSerendipity-io13

Source code for the Geek Serendipity Android + Google Cloud Platform demo at Google IO 2013
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GeoHashing #2

Open vdisawar opened 11 years ago

vdisawar commented 11 years ago

Hi,

I had a question with the geohasher class in this project. I mainly wanted to ask what is beneficial with converting LatLng coordinates to a geohash and how accurate is it?

thanks

I know this isn't an issue but I didn't know where to post the questions.

turbomanage commented 11 years ago

I believe the accuracy is a few meters for the full base 32 geohash. However, using a geohash to query proximity is tricky since you may be near a hash boundary. For that reason, it is actually not used in the current project. We decided to query the most recent position updates from anywhere in the world instead. It was used in an earlier version.

The geohash algorithm we used is this one: http://en.wikipedia.org/wiki/Geohash

HTH, /dmc

On Thu, Jun 27, 2013 at 2:18 PM, vdisawar notifications@github.com wrote:

Hi,

I had a question with the geohasher class in this project. I mainly wanted to ask what is beneficial with converting LatLng coordinates to a geohash and how accurate is it?

thanks

— Reply to this email directly or view it on GitHubhttps://github.com/bradabrams/GeekSerendipity-io13/issues/2 .

vdisawar commented 11 years ago

So in order to query locations on app engine, is it possible to just use lat, lng values instead of geohashing and are there any downsides to that approach, if any?