Performance of Damerau Levenshtein is low

[nanthony007]

I am unsure as to the cause of this. I know the DL algorithm is significantly more complex than the OSA algorithm but some crude benchmarks show the results below when simply comparing "alcohol" and "acloholism".

I just wanted to post this to ensure the algorithm has the correct implementation given this package's large usage rate.

Times below are average benchmarks in nanoseconds.

[maxbachmann]

9d0a950 improves the performance significantly. E.g. for your strings I do now get the following runtimes on my machine:

test benches::bench_damerau_levenshtein            ... bench:         219 ns/iter (+/- 8)
test benches::bench_jaro_winkler                   ... bench:          63 ns/iter (+/- 1)
test benches::bench_levenshtein                    ... bench:          87 ns/iter (+/- 1)
test benches::bench_osa_distance                   ... bench:         136 ns/iter (+/- 3)
test benches::bench_sorensen_dice                  ... bench:         365 ns/iter (+/- 8)

while previously I would get:

test benches::bench_damerau_levenshtein            ... bench:         735 ns/iter (+/- 15)

[nanthony007]

This is awesome thank you! Much more in line with what I was expecting perf wise. Will there be a new crates.io release for the functionality you've been adding?

[maxbachmann]

Yes there will be a new release soon. Probably once we have #58 merged.