The erlang-h3 library provides an Erlang binding for Uber's
H3 spatial coordinate library.
Add h3 to your deps section in rebar.config:
{deps, [h3]}.Fork the repo and simply use make to build the library. You will
need cmake installed to build the required h3 core package.
To run the tests run make test.
Cross-compilation requires the environment variable ERTS_INCLUDE_DIR
defined as the target directory containing erl_nif.h,
e.g. ERTS_INCLUDE_DIR=target/usr/lib/erlang/erts-<VERSION>/include.
The h3 module exports most of the functions from the core H3 library.
Like the JavaScript version the Erlang binding uses degrees instead of radians when converting to and from geo-coordinates to h3 indexes.
Example using ./rebar3 shell after cloning the repo:
$ ./rebar3 shell
...
1> Paris = h3:from_geo({48.8566, 2.3522}, 9).
617550903642685439
2> h3:to_string(Paris).
"891fb466257ffff"
3> h3:to_geo(Paris).
{48.857078058197295,2.3529900909549206}