summary

iwi is a simple Lua geohash binding for libgeohash.

WTF iwi means?

iwi is a nheengatu word that means "land" or even "earth" in some concepts.

help and support

please fill an issue or help it doing a clone and then a pull request.

license

LGPL version 3, see COPYING and source

prerequisites

• libgeohash (of course)
• Lua (Luajit)
• gcc and make (min-gw32 on windows)
• upx (optional)

installation

luarocks

# luarocks install iwi

make

compatible with *NIX systens, supposed to works on windows. You only need to edit some vars on makefile, for basic instalation use:

# make

if you have upx use this for better output.

# make release

for cleanup

# make clean

basic usage

local gh = require('iwi')

-- directions
--[[
gh.west
gh.east
gh.north
gh.south
--]]
-- units
--[[
gh.miles
gh.kilometers
]]

-- encodes latitude, and longitude with length
-- returns geohash
local geohash = gh.encode(23.11, 47.999, 5)

-- decodes geohash
-- returns min_latiture, max_latitude, min_longitude and max_longitude 
local min_lat, max_lat, min_lon, max_lon = gh.decode("abY9x")

-- get adjacent hash by origin's hash and direction
-- returns adjacent hash
local adj_geohash = gh.adjacent("abY9x", gh.west) -- or .east, .north, .south

-- get neighbors' hash by origin's hash
-- return a table with north, north_east, north_west, 
--   south, south_east, south_west, east and west neighbors
local neighbors = gh.neighbors("abY9x")

-- this is an extra feature, i think it might be useful
-- get distance between two pairs of longitude and latitude with optional unit,
--   defaults to kilometers
local distance = gh.distance(lat, lon, lat2, lon2, gh.kilometers) -- or gh.miles or nothing

-- another extra feature.
-- get resulting latitude and longitude according to bearing and distance with optional unit,
--   defaults to kilometers
local destination = gh.destination(lat, lon, 90.0, 5.6) -- or gh.miles or nothing

-- verify geohash, returns boolean
print(gh.verify("abY9x"))

tests

run busted, see spec folder