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Questions tagged [geohashing]

Geohash is a latitude/longitude encoding system using Base-32 characters.

Geohash is a latitude/longitude geocode system invented by Gustavo Niemeyer when writing the web service at geohash.org, and put into the public domain. It is a hierarchical spatial data structure which subdivides space, then interleaves the latitude and longitude information in a bitwise fashion.

Geohashes offer properties like arbitrary precision and the possibility of gradually removing characters from the end of the code to reduce its size (and gradually lose precision).

Nearby places will often (but not always) present similar prefixes. The longer a shared prefix is, the closer the two places are.

See https://en.wikipedia.org/wiki/Geohash

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How to use geohash in Angular 6

I am using angular google map to to create polygon and I need to convert the co-ordinates to geohash. I checked around but didn't find anything on angular regarding this, So please help out any help would be appreciated. Thanks
Mohd Mobeen
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Can Geotools create a Geohash from a lat and lon?

Recently I have been using the Geotools library (http://docs.geotools.org/latest/javadocs/) to process some simple geo data. However, the library is so robust that it is surprising to me that it doesn't seem to provide the capability to create…
Chris D.
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how to calculate the area of Geohash?

I known the area of geohash(precision is 5)is 10 square kilometres. But I want to know the area of geohash(precision is 4) and I dont't know how to calculate. I read the wiki about Geohash, but I still get…
weijian
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Standardizing GPX traces

I have two GPX files (from a race I ran twice, obtained via the Strava API) and I would like to be able to compare the effort across both. The sampling frequency is irregular however (i.e. data is not recorded every second, or every meter), so a…
Tom Tourwe
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GeoHash Function not returning correct result

I am trying to write a geohashing function that takes a latitude/longitude pair and returns its base2 (geohash once converted to base32) string. However, this is giving me incorrect results. What is wrong with it? public static void main(String[]…
jLangley011
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How does Geofire calculate bounding geohashes for Firebase queries?

Context I've used Geofire along with Firebase for a while now and I got really curious how Geofire performs its queries. I understand that semantically, it's a function of coordinates and a radius that results in a minimum and maximum hashes. So the…
ThunderStruct
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Difference between geohash and place ID in google maps api

Is geohash and Place ID in google maps api similar thing? if not, then on what criteria Place ID is defined?
Mehreen Qaysar
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Generating a list of geohashes with a geohash length/precision of 4 in PHP

I would appreciate it if someone could lead me in the right direction to finding a solution to an issue I'm having with regard to a problem. I need to generate all possible geo hashes of the globe with a precision of 4, This is so I can build a…
Anand Davis
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Finding the closest location to a lat and long value

I have two tables t1 and t2 (t1 has 1/10th of the size of t2). Each table has two columns that contain the latitude and longitude of some points. For each row in t1 I'd like to find the row in t2 that is the closest to it. What would be…
Mark
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Use GIS to get geographic info for a single point

I am not quite sure where to start with this. I only just started looking into this in the past week, but hopefully someone can help point me in the right direction. The goal of my project is to be able to take a geohash, decode it to latitude and…
Patrick Lee Scott
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App Engine - Precomputing bounding boxes for proximity search

I'm trying to do a location-based search on App Engine, but since the data store doesn't support multiple inequality operators, I can't search "where lat between a and b and lon between c and d". One of the solutions is to pre-compute bounding boxes…
Danny Tuppeny
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Elastic Search geohashes return full details not just doc_count

I am working on a property aggrigation website that would store hundred of thosuands of properties. To map areas I am using Elastic Search's GEO Hashing to reduce the number of matches returned for a given zoom level. The code to generate the…
Paul Danelli
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Geohashes - Why is interleaving index values necessary?

I have had a look at this post about geohashes. According to the author, the final step in calculating the hash is interleaving the x and y index values. But is this really necessary? Is there a proper reason not to just concatenate these values, as…
A Friedrich
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Geohash Oracle implementation

I found lots of implementations of Geohash, for lots of technologies. But I wasn't be able to find anyone for Oracle. Does anyone know how to use Geohash in Oracle? Is there any Geohash implementation? I would need a encoder and decoder, but the…
Nicolas Rodriguez
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How does geohash index work in Lucene

In lucene spatial 4 I'm wondering how the geohash index works behind the scenes. I understand the concept of the geohash which basically takes 2 points (lat, lon) and creates a single "string" hash. Is the index just a "string" index (r-tree or…
user2092856
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