A HyperLogLog implementation in Rust, with bias correction.
Installation: use Cargo.
Usage:
let mut hll = HyperLogLog::new(error_rate);
hll.insert(~"test1");
hll.insert(~"test2");
let card_estimation = hll.len();
let mut hll2 = HyperLogLog::new_from_template(&hll);
hll2.insert(~"test3");
hll.merge(&hll2);