https://github.com/wstucco/geohash_nif

Elixir NIF for Geohash C Library
https://github.com/wstucco/geohash_nif

Last synced: about 2 months ago
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Elixir NIF for Geohash C Library

• Host: GitHub
• URL: https://github.com/wstucco/geohash_nif
• Owner: wstucco
• License: apache-2.0
• Created: 2020-07-07T13:29:42.000Z (almost 4 years ago)
• Default Branch: master
• Last Pushed: 2020-07-07T13:40:09.000Z (almost 4 years ago)
• Last Synced: 2024-04-16T08:26:54.898Z (2 months ago)
• Language: Elixir
• Size: 61.5 KB
• Stars: 1
• Watchers: 1
• Forks: 1
• Open Issues: 0
• Metadata Files:
  • Readme: README.md
  • License: LICENSE

Lists

• awesome-elixir - geohash_nif - Drop in replacement for Geohash encode/decode library implemented as a NIF. (Geolocation)

README

        
# GeohashNif

Drop in replacement fot the Elixir native [Geohash encode/decode library](https://hexdocs.pm/geohash/) implemented as a NIF

## Installation

The package can be installed by adding geohash_nif to your list of dependencies in mix.exs:

```elixir

def deps do

  [{:geohash_nif, "~> 1.0"}]

end

```

## Basic Usage

```elixir

iex(1)> Geohash.encode(42.6, -5.6, 5)

"ezs42"

iex(1)> Geohash.decode("ezs42")

{42.605, -5.603}

iex(1)> Geohash.neighbors("ezs42")

%{

  "e" => "ezs43",

  "n" => "ezs48",

  "ne" => "ezs49",

  "nw" => "ezefx",

  "s" => "ezs40",

  "se" => "ezs41",

  "sw" => "ezefp",

  "w" => "ezefr"

}

iex(1)> Geohash.adjacent("ezs42","n")

"ezs48"

iex(1)> Geohash.bounds("u4pruydqqv")

%{

  max_lat: 57.649115324020386,

  max_lon: 10.407443046569824,

  min_lat: 57.649109959602356,

  min_lon: 10.407432317733765

}

```

Full documentation can be found at [https://hexdocs.pm/geohash_nif](https://hexdocs.pm/geohash_nif).

##  Differences to Geohash

For compatibility reasons `Geohash.neighbors/2` returns a map with string as keys,

but passing the option `keys: :atoms` a different implementation is called

which returns a map with atom as keys.

The atoms implementation is ~30% faster and uses ~40% less memory.

## Benchmarks

Included witht the library there is a complete suite of benchmarks available

as the `bench` mix task.

### Usage:

```bash

$ mix help bench

Bench Geohash NIF against Gehohash native Elixir implementation

## Usage

mix bench  [ ...]

If  is omitted or one of them is `all` runs all the benchmarks.

 can be a single value or a list of values separated by spaces.

Invalid values are simply ignored.

Valid  values are

  • encode

  • decode

  • bounds

  • adjacent

  • neighbors

  • decode_to_bits

## Examples

  • $ mix bench - runs all the benchmarks

  • $ mix bench all - runs all the benchmarks

  • $ mix bench encode - runs the encode benchmark

  • $ mix bench encode decode - runs the encode and decode benchmarks

  • $ mix bench xxx all yyy - runs all benchmarks

```

Detailed benchmarks (including memory measurements): [benchmarks.txt](https://gitlab.com/wstucco/geohash_nif/-/raw/master/benchmarks.txt)

## License

GohashNif is released under the Apache License 2.0 - see the [LICENSE](https://gitlab.com/wstucco/geohash_nif/-/raw/master/LICENSE) file.

The code for the C geohash library is released under the MIT license - see the [LICENSE.geohash](https://gitlab.com/wstucco/geohash_nif/-/raw/master/LICENSE.geohash)