dfdx / HyperLogLog.jl

HyperLogLog in Julia

HyperLogLog.jl

NOTICE

This package is unmaintained. Its reliability is not guaranteed.

Introduction

A simple HyperLogLog implementation in Julia

Usage Examples

In this example, we'll create a HyperLogLog counter with quality value 8:

using HyperLogLog

counter = HLL(8)

consume!(counter, 1:100)
estimate(counter)

consume!(counter, 101:1000)
estimate(counter)

Note that the quality value must be an integer between 4 and 16. When selecting a value, keep in mind that the memory costs for using value b scales like 2^b.

In this example, we'll use a custom hash function:

using HyperLogLog

counter = HLL(8, x -> uint32(hash(x)))

consume!(counter, 1:100)
estimate(counter)

consume!(counter, 101:1000)
estimate(counter)

Note that the hash function must return a Uint32. This is done to be consistent with the theory presented in the original HyperLogLog paper. We may allow 64-bit hashes in the future.