rurban / smhasher

Hash function quality and speed tests
https://rurban.github.io/smhasher/
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FEATURE: Add a significantly improved collision estimation function #240

Closed fwojcik closed 2 years ago

fwojcik commented 2 years ago

This uses a justified bound for using p(collisions >= 1) as an estimator for E[number of collisions], which lets it use the known-good approximation for hash counts under that limit.

Also improve --EstimateNbCollision test output, expand its list of hash counts and bit widths to cover more values that are used in the tests, and add exact true values along with a utility to compute them via arbitrary-precision libraries.

rurban commented 2 years ago

Already in the branch fwojcik