https://github.com/lauraschlimmer/redis_geohash

Spatial indexing and proximity search for redis with geohashes
https://github.com/lauraschlimmer/redis_geohash

Last synced: 10 days ago
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Spatial indexing and proximity search for redis with geohashes

• Host: GitHub
• URL: https://github.com/lauraschlimmer/redis_geohash
• Owner: lauraschlimmer
• Created: 2012-01-07T02:29:34.000Z (almost 13 years ago)
• Default Branch: master
• Last Pushed: 2012-01-29T03:26:26.000Z (almost 13 years ago)
• Last Synced: 2024-10-31T19:42:56.724Z (17 days ago)
• Language: Ruby
• Homepage:
• Size: 99.6 KB
• Stars: 59
• Watchers: 3
• Forks: 12
• Open Issues: 0
• Metadata Files:
  • Readme: README.md

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README

        
redis_geohash

=============

location-aware lists + simple distance calculation with geohashes and ruby/redis. geohash implementation in pure ruby.

[ ![Build status - Travis-ci](https://secure.travis-ci.org/paulasmuth/redis_geohash.png) ](http://travis-ci.org/paulasmuth/redis_geohash)

http://en.wikipedia.org/wiki/Geohash

---

### using redis_geohash

`RedisGeohash.connect!` is only necessary if you want to use LookupTables.

```ruby

require "redis"

require "redis_geohash"

my_redis = Redis.new

RedisGeohash.connect!(my_redis)

```

---

### location aware lists

Every `RedisGeohash::LookupTable` will create 8 redis-keys (hashes). Precision can be 0-8. Use `:no_reverse_lookup => true` to disable the second lookup pass (much faster, less acurate).

```ruby

# create a namespace

geo_tbl = RedisGeohash::LookupTable.new('my_world')

# store the first items

geo_tbl.store!(:id => '23422342', :lat => ..., :lng => ...)

geo_tbl.store!(:id => '55552323', :lat => ..., :lng => ...)

# do a radius/grid search

geo_tbl.lookup(:lat => ..., :lng => ..., :precision => 4)

# => ['23422342', '55552323', ...]

# do a fast radius/grid search

geo_tbl.lookup(:lat => ..., :lng => ..., :precision => 4, :no_reverse_lookup => true)

# => ['23422342', '55552323', ...]

```

---

### creating hashes manually

Hashes can be created without a redis connection

```ruby

# create from lat/lng

geo_hash = RedisGeohash::GeoHash.new(:lat => ..., :lng => ...)

# create from geohash string

geo_hash = RedisGeohash::GeoHash.new("u33dc1f0j1nqg")

geo_hash.geohash

# => "u33dc1f0j1nqg"

geo_hash.coordinates

# => {:lat => ..., :lng => ...}

geo_hash.adjacents

# => [, , ...]

```

---

### bonus: distance calculation

Pass in two lat/lng-hashes or two `RedisGeohash::GeoHash` objects.

```ruby

RedisGeohash.distance({:lat => ..., :lng => ...}, {:lat => ..., :lng => ...})

#  => 34,654

RedisGeohash.distance(geo_hash_one, geo_hash_two)

#  => 34,654

```

Installation

------------

    gem install redis_geohash

or in your Gemfile:

    gem 'redis_geohash', '~> 0.1'

Caveats

-------

+ There is currently no (atomic) way to remove ids from a table

Todos

-----

+ remove range monkeypatch

License

-------

Copyright (c) 2011 Paul Asmuth

Permission is hereby granted, free of charge, to any person obtaining

a copy of this software and associated documentation files (the

"Software"), to use, copy and modify copies of the Software, subject 

to the following conditions:

The above copyright notice and this permission notice shall be

included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,

EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF

MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND

NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE

LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION

OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION

WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.