An implementation of various Approximate Set Membership structures in Rust. Currently included are a standard Bloom Filter, and the simplest kind of Counting Bloom Filter.
At some point more advanced types of ASMSes will be added.
rust
extern crate bloom;
use bloom::BloomFilter;
let expected_num_items = 1000;
let false_positive_rate = 0.01;
let mut filter:BloomFilter = BloomFilter::with_rate(false_positive_rate,expected_num_items);
filter.insert(&1i);
filter.contains(&1i); /* true */
filter.contains(&2i); /* false */
Use Cargo and add the following to your Cargo.toml
[dependencies]
bloom="0.2.0"
The false positive rate is specified as a float in the range
(0,1). If indicates that out of X probes, X * rate should
return a false positive. Higher values will lead to smaller (but
more inaccurate) filters.
This crate includes some benchmarks to test the performance of the bloom filter. To run them you'll need to use rust nightly (the benchmark feature isn't stable yet), and then run:
cargo bench --features "do-bench"