Use a flat vector in Damerau-Levenshtein Instead of representing a 2x2 grid with a vector of vectors, just use a single vector to improve performance. We can do this since the dimensions are fixed. This method was suggested by @lovasoa as an alternative to adding a dependency on the ndarray crate. In my benchmark testing, the new approach is about as fast using ndarray. On my machine, the original approach takes about 22,000 ns/iter, whereas the new approach takes about 17,000 ns/iter. See https://github.com/dguo/strsim-rs/issues/34 for more context.
Rust implementations of string similarity metrics:
The normalized versions return values between 0.0 and 1.0, where 1.0 means an exact match.
There are also generic versions of the functions for non-string inputs.
strsim is available on crates.io. Add it to your Cargo.toml:
[dependencies] strsim = "0.9.0"
Go to Docs.rs for the full documentation. You can also clone the repo, and run $ cargo doc --open.
extern crate strsim; use strsim::{hamming, levenshtein, normalized_levenshtein, osa_distance, damerau_levenshtein, normalized_damerau_levenshtein, jaro, jaro_winkler}; fn main() { match hamming("hamming", "hammers") { Ok(distance) => assert_eq!(3, distance), Err(why) => panic!("{:?}", why) } assert_eq!(levenshtein("kitten", "sitting"), 3); assert!((normalized_levenshtein("kitten", "sitting") - 0.571).abs() < 0.001); assert_eq!(osa_distance("ac", "cba"), 3); assert_eq!(damerau_levenshtein("ac", "cba"), 2); assert!((normalized_damerau_levenshtein("levenshtein", "löwenbräu") - 0.272).abs() < 0.001); assert!((jaro("Friedrich Nietzsche", "Jean-Paul Sartre") - 0.392).abs() < 0.001); assert!((jaro_winkler("cheeseburger", "cheese fries") - 0.911).abs() < 0.001); }
Using the generic versions of the functions:
extern crate strsim; use strsim::generic_levenshtein; fn main() { assert_eq!(2, generic_levenshtein(&[1, 2, 3], &[0, 2, 5])); }
If you don't want to install Rust itself, you can run $ ./dev for a development CLI if you have Docker installed.
Benchmarks require a Nightly toolchain. Run $ cargo +nightly bench.