# Strsim
[](https://hex.pm/packages/strsim)
[](https://coveralls.io/github/joshrotenberg/strsim_ex?branch=master)
Strsim is an [Elixir][0] wrapper for the [Rust][1] [strsim][2] crate with [Rustler][3].
## Summary
Strsim is a NIF-based bridge for the [strsim][2] [Rust][1] library which implements the following string similarity algorithms:
* Levenshtein
* Damerau-Levensthein
* Jaro
* Jaro-Winkler
* Hamming
* Optimal String Alignment
* Sørensen–Dice
The crate offers several functions for both strings and generic sequences, and this library exposes all of them except for the generic Damerau-Levenshtein for now.
## Usage
All of the functions in the crate have equivalent Elixir functions:
```
iex(1)> Strsim.damerau_levenshtein("ab", "bca")
{:ok, 2}
iex(2)> Strsim.generic_hamming([1, 2], [1, 3])
{:ok, 1}
iex(3)> Strsim.generic_jaro([1, 2], [1, 3, 4])
{:ok, 0.611111111111111}
iex(4)> Strsim.generic_jaro_winkler([1, 2], [1, 3, 4])
{:ok, 0.6499999999999999}
iex(5)> Strsim.generic_levenshtein([1, 2, 3], [1, 2, 3, 4, 5, 6])
{:ok, 3}
iex(6)> Strsim.hamming("hamming", "hammers")
{:ok, 3}
iex(7)> Strsim.hamming("hamming", "ham")
{:error, :different_length_args}
iex(8)> Strsim.jaro("Friedrich Nietzsche", "Jean-Paul Sartre")
{:ok, 0.39188596491228067}
iex(9)> Strsim.jaro_winkler("cheeseburger", "cheese fries")
{:ok, 0.9111111111111111}
iex(10)> Strsim.levenshtein("kitten", "sitting")
{:ok, 3}
iex(11)> Strsim.normalized_damerau_levenshtein("levenshtein", "löwenbräu")
{:ok, 0.2727272727272727}
iex(12)> Strsim.normalized_levenshtein("kitten", "sitting")
{:ok, 0.5714285714285714}
iex(13)> Strsim.osa_distance("ab", "bca")
{:ok, 3}
iex(14)> Strsim.sorensen_dice("ferris", "feris")
{:ok, 0.8888888888888888}
```
## Benchmarks
Everybody loves benchmarks. There are results for all implemented [strsim](bench/strsim_benchmark_results.md)
as well as [jaro](bench/jaro_benchmark_results.md), [jaro_winkler](bench/jaro_winkler_benchmark_results.md), [levenshtein](bench/levenshtein_benchmark_results.md) and [hamming](bench/hamming_benchmark_results.md) comparing the Rust and various Elixir implementations.
To run the benchmarks:
```
# run Elixir vs Rust Jaro benchmarks
$ MIX_ENV=bench mix bench.jaro
# run Elixir vs Rust Jaro-Winkler benchmarks
$ MIX_ENV=bench mix bench.jaro_winkler
# run Elixir vs Rust levensthein benchmarks
$ MIX_ENV=bench mix bench.levenshtein
# run Elixir vs Rust hamming benchmarks
$ MIX_ENV=bench mix bench.hamming
# run a benchmark will all of the Rust functions
$ MIX_ENV=bench mix bench.strsim
# run 'em all
$ MIX_ENV=bench mix bench.all
```
## See also
* [fuzzy_compare][4]
* [levenshtein][5]
* [String.jaro_distance/2][6]
* [the_fuzz][7]
* [simetric][8]
## Installation
The package can be installed
by adding `strsim` to your list of dependencies in `mix.exs`:
```elixir
def deps do
[
{:strsim, "~> 0.1.1"}
]
end
```
Documentation can be generated with [ExDoc](https://github.com/elixir-lang/ex_doc)
and published on [HexDocs](https://hexdocs.pm). Once published, the docs can
be found at [https://hexdocs.pm/strsim](https://hexdocs.pm/strsim).
[0]: https://elixir-lang.org
[1]: https://www.rust-lang.org
[2]: https://crates.io/crates/strsim
[3]: https://hex.pm/packages/rustler
[4]: https://hex.pm/packages/fuzzy_compare
[5]: https://hex.pm/packages/levenshtein
[6]: https://hexdocs.pm/elixir/String.html#jaro_distance/2
[7]: https://hex.pm/packages/the_fuzz
[8]: https://hex.pm/packages/simetric
