Struct StableBloomFilter 

pub struct StableBloomFilter { /* private fields */ }

Stable bloom filter, the best choice for small data set. In this structure, k hash functions share a global bitmap, whose max size is u64::MAX. Usage:

use roaring_bloom_filter::*;

let mut bf = StableBloomFilter::new(100, 0.001_f64);

bf.add(&10);
bf.add(&'a');
bf.add(&"a string");

bf.contains(&12);

Stable Bloom Filter(SBF)

All hash function share the whole bitmap. Best choice for relatively small dataset.

Implementations

impl StableBloomFilter

pub fn from_scratch( hash_num: u32, bitmap_size: u64, target_false_positive_rate: f64, ) -> StableBloomFilter

Create an empty stable bloom filter from scratch.

Generally, user should not use this initializer directly. Promise the limitation on yourself:

• 0 < k <= u32::MAX
• 0 < m <= u32::MAX
• 0 < f < 1

pub fn new(max_size: u64, target_false_positive: f64) -> impl BloomFilter

Create an empty bloom filter with max element’s size and false positive rate. The crate would calculate the best hash number and bitmap size.

Trait Implementations

impl BloomFilter for StableBloomFilter

fn add<T>(&mut self, value: &T) -> bool

where T: Hash,

Add new element into the bloom filter. Return true when any key are inserted in a slice.

fn contains<T>(&self, value: &T) -> bool

where T: Hash,

Check if the bloom filter contains the specific key. Return true when all key are present in all slices, which may contains false positive situation.

fn target_false_positive_rate(&self) -> f64

Get target false positive rate.

fn current_false_positive_rate(&self) -> f64

Get current false positive rate.

fn is_empty(&self) -> bool

If this bloom filter is empty.

fn is_full(&self) -> bool

If this bloom filter is full.

fn size(&self) -> u64

Get the number of inserted elements in this bloom filter.

fn len(&self) -> u64

Get the number of inserted bits in all slices.

impl Display for StableBloomFilter

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.