twitter/algebird — pull request #72 by asiegel34 (2012-12-15 00:22:41+00:00)
Title: HyperLogLog refactoring + sparse vector implementation

This is a reimplementation of HyperLogLog using sparse vectors in place of single items. It should be *much* more space efficient in applications that involve lots of small datasets with tight error bounds.

Many functions in the HyperLogLogMonoid class have been factored out into HLL (but with the public endpoints left in place for backward compatibility).