Struct hyperloglogplus::HyperLogLogPF

pub struct HyperLogLogPF<H: ?Sized, B> where
    H: Hash,
    B: BuildHasher,  { /* fields omitted */ }

Implements the original HyperLogLog algorithm for cardinality estimation.

This implementation is based on the original paper of P. Flajolet et al:

HyperLogLog: the analysis of a near-optimal cardinality estimation algorithm.

• Uses 5-bit registers, packed in a 32-bit unsigned integer. Thus, every six registers 2 bits are not used.
• Supports serialization/deserialization through serde.
• Compiles in a no_std environment using a global allocator.

Examples

use std::collections::hash_map::RandomState;
use hyperloglogplus::{HyperLogLog, HyperLogLogPF};

let mut hll: HyperLogLogPF<u32, _> =
    HyperLogLogPF::new(16, RandomState::new()).unwrap();

hll.insert(&12345);
hll.insert(&23456);

assert_eq!(hll.count().trunc() as u32, 2);

References

• “HyperLogLog: the analysis of a near-optimal cardinality estimation algorithm”, Philippe Flajolet, Éric Fusy, Olivier Gandouet and Frédéric Meunier.

Implementations

impl<H: ?Sized, B> HyperLogLogPF<H, B> where
    H: Hash,
    B: BuildHasher, 

pub fn new(precision: u8, builder: B) -> Result<Self, HyperLogLogError>

Creates a new HyperLogLogPF instance.

pub fn merge<S: ?Sized, T>(
    &mut self,
    other: &HyperLogLogPF<S, T>
) -> Result<(), HyperLogLogError> where
    S: Hash,
    T: BuildHasher, 

Merges the other HyperLogLogPF instance into self.

Both sketches must have the same precision.

pub fn insert_any<R: ?Sized>(&mut self, value: &R) where
    R: Hash, 

Inserts a new value, of any type, to the multiset.

Trait Implementations

impl<H: Clone + ?Sized, B: Clone> Clone for HyperLogLogPF<H, B> where
    H: Hash,
    B: BuildHasher, 

fn clone(&self) -> HyperLogLogPF<H, B>

Returns a copy of the value.

pub fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<H: Debug + ?Sized, B: Debug> Debug for HyperLogLogPF<H, B> where
    H: Hash,
    B: BuildHasher, 

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

Formats the value using the given formatter.

impl<'de, H: ?Sized, B> Deserialize<'de> for HyperLogLogPF<H, B> where
    H: Hash,
    B: BuildHasher,
    B: Deserialize<'de>, 

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error> where
    __D: Deserializer<'de>, 

Deserialize this value from the given Serde deserializer.

impl<H: ?Sized, B> HyperLogLog<H> for HyperLogLogPF<H, B> where
    H: Hash,
    B: BuildHasher, 

fn add(&mut self, value: &H)

👎 Deprecated since 0.3.0:

use insert() function instead.

Adds a new value to the multiset.

fn insert<Q: ?Sized>(&mut self, value: &Q) where
    H: Borrow<Q>,
    Q: Hash, 

Inserts a new value to the multiset.

fn count(&mut self) -> f64

Estimates the cardinality of the multiset.

impl<H: ?Sized, B> Serialize for HyperLogLogPF<H, B> where
    H: Hash,
    B: BuildHasher,
    B: Serialize, 

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error> where
    __S: Serializer, 

Serialize this value into the given Serde serializer.