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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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Geofire very slow at retrieving keys/ not scaling well

I have a dating application iOS and Android that's retrieving keys slow up-to 10 seconds. I've followed all the recommendations on firebase real-time documentation but as I'm getting more users it's affecting the performance of my application. I've…
EmanRobi
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Dividing Query on Geospatial Index

I'm looking into storing geospatial information using a geohash-like index, perhaps using Hilbert curves. My question is regarding how best to split up area queries on such an index. This article for example shows how one might want to split an area…
dylan.scott
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How to find documents in an x mile radius using geohashes without filtering on client?

So currently I am using geohashes to do location based queries as such (following this stackoverflow post: Finding geohashes of certain length within radius from a point) public extension CLLocationCoordinate2D { func boundingBox(radius:…
Kunal M
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Flutter .where and .orderBy queries against Firebase problem

I'm writing a Flutter application which uses the user's location to identify items around them. As it's only possible to do comparison queries against one field in Firebase, I'm using geohashes as per Frank van Puffelen's lecture on the…
Anthony Rodgers
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Convert long pandas dataframe to numpy 2d rectangular array

I have the following in a pandas dataframe: z | x | y | hash _________________ a | 0.0 | 1.0 | abcd b | 1.0 | 1.0 | efghj c | 1.0 | 0.0 | iklmno d | 0.0 | 0.0 | pqrs (Where Z represents digital elevation, x and y are lat, long, and hash is a…
Sean Carter
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Scala: library to get geohashes from WKT linestring

I have a WKT Linestring, let's say: LINESTRING (11.782009 42.099761, 11.781858 42.099615, 11.782359 42.100029) From this path, I want to get the list of geohashes that it goes through. In python, there is https://github.com/mathieuripert/geoh . A…
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How do you ID GeoHash points that are NOT over land?

I have a list of coordinates in latitude/longitude that I have converted to GeoHash. My goal is to ID the points that are reported to be over water (oceans, seas, etc. outside of any countries borders). I also have a data set of all the shapes of…
Zack
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Retreiving neighbors with geohash algorithm?

I am looking at a pythonic implementation of this top rated accepted answer on GIS SE - Using geohash for proximity searches? and I am unable to retrieve any matches for my geohash query. Here is the approach I have tried so far. To run this Minimum…
gansub
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How can I create a scalable in-memory geohash?

I've been using Redis's Geohash capability. However, it doesn't seem this can scale well, as the index is implemented as a SortedSet, which cannot be partitioned. What is recommended for this problem? I will have frequent writes and reads both.
vmayer
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GeoFire read ops efficiency

I'm using geofire to query Firestore as a user walks around. Here's my question: Let's say my Firestore database has 5000 geohashed records in it and they're randomly located around the world. The records are all stored off a root node in the db.…
Reckless
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reverse where query in mysql2

I want to find records using like query but in reverse mode For exa: I have one string ts5e434 And now in databse I have one column called geohash and its contan comma seperated values 1) "ts5e4,ts5,ts5e434" 2) "ab,ye" 3) "ts,thh" 4) "t" So here I…
ashvin
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What latitude / longitude combination will produce a negative geohash integer?

I'm trying to write a simple go application that interfaces with DynamoDB to store points as a geohash. Essentially I'm trying to replicate what the Java geo lib for DynamoDB does, but with Go. I'm using https://github.com/mmcloughlin/geohash to…
rynop
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Unable to install python-geohash using PIP in mac terminal

Installing python-geocode has not been easy. I'm running Anaconda on my mac (10.14.4), and in terminal, I'm using: pip install python-geohash I get the following error: warning: include path for stdlibc++ headers not found; pass…
DiamondJoe12
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Ordering Firestore GeoHash query from closest to furthest?

Currently, I'm using parts of the GeoFirebase library along with Firestore to allow for geoquerying. When I set the geohash of a post, I do it as such if let geoHash = GFGeoHash(location: location.coordinate).geoHashValue { However, to make the…
Raim Khalil
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How can I decode GeoHashes generated by GeoFire?

I'm new in Android Developing and will greatly appreciate any guidance. I would like to know if there is a way to decode the GeoHashes generated by GeoFire when saving coordinates to Firebase. I don't see services from GeoFire that decode the…
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