githaven/vendor/github.com/couchbase/vellum/levenshtein/README.md
2019-11-27 11:23:33 +02:00

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# levenshtein
levenshtein automaton
This package makes it fast and simple to build a finite determinic automaton that computes the levenshtein distance from a given string.
# Sample usage:
```
// build a re-usable builder
lb := NewLevenshteinAutomatonBuilder(2, false)
origTerm := "couchbasefts"
dfa := lb.BuildDfa("couchbases", 2)
ed := dfa.eval([]byte(origTerm))
if ed.distance() != 2 {
log.Errorf("expected distance 2, actual: %d", ed.distance())
}
```
This implementation is inspired by [blog post](https://fulmicoton.com/posts/levenshtein/) and is intended to be
a port of original rust implementation: https://github.com/tantivy-search/levenshtein-automata
Micro Benchmark Results against the current vellum/levenshtein is as below.
```
BenchmarkNewEditDistance1-8 30000 52684 ns/op 89985 B/op 295 allocs/op
BenchmarkOlderEditDistance1-8 10000 132931 ns/op 588892 B/op 363 allocs/op
BenchmarkNewEditDistance2-8 10000 199127 ns/op 377532 B/op 1019 allocs/op
BenchmarkOlderEditDistance2-8 2000 988109 ns/op 4236609 B/op 1898 allocs/op
```