Algorithm::HyperLogLog - Implementation of the HyperLogLog cardinality estimation algorithm

       Hideaki Ohno <hide.o.j55 {at} gmail.com>

       This module is implementation of the HyperLogLog algorithm.

       HyperLogLog is an algorithm for estimating the cardinality of a set.

       This  library  is  free  software;  you can redistribute it and/or modify it under the same terms as Perl
       itself.

perl v5.40.0                                       2024-10-20                        Algorithm::HyperLogLog(3pm)

new($b)
       Constructor.

       `$b` is the parameter for determining register size. (The register size is 2^$b.)

       `$b` must be a integer between 4 and 16.

   new_from_file($filename)
       This method constructs object and restore the internal data of object from dumped file(dumped by
       dump_to_file() method).

   dump_to_file($filename)
       This method dumps the internal data of an object to a file.

   add($data)
       Adds element to the cardinality estimator.

   estimate()
       Returns estimated cardinality value in floating point number.

   merge($other)
       Merges the estimate from 'other' into this object, returning the estimate of their union.

   register_size()
       Return number of register.(In the XS implementation, this equals size in bytes)

   XS()
       If using XS backend, this method return true value.

       Algorithm::HyperLogLog - Implementation of the HyperLogLog cardinality estimation algorithm

       Philippe Flajolet, Éric Fusy, Olivier Gandouet and Frédéric Meunier. HyperLogLog: the analysis of a near-
       optimal cardinality estimation algorithm. 2007 Conference on Analysis of Algorithms, DMTCS proc. AH, pp.
       127–146, 2007. <http://algo.inria.fr/flajolet/Publications/FlFuGaMe07.pdf>

         use Algorithm::HyperLogLog;

         my $hll = Algorithm::HyperLogLog->new(14);

         while(<>){
             $hll->add($_);
         }

         my $cardinality = $hll->estimate(); # Estimate cardinality
         $hll->dump_to_file('hll_register.dump');# Dumps internal data

       Construct object from dumped file.

         use Algorithm::HyperLogLog;

         # Restore internal state
         my $hll = Algorithm::HyperLogLog->new_from_file('hll_register.dump');

       MurmurHash3(<https://github.com/PeterScott/murmur3>)

       Austin Appleby
       Peter Scott