New Adventures in Software by Dan Dyer

Just to clear up a possible misconception, Uncommons Maths is not intended as a slight against Apache Commons Math (regardless of the incidental mention Commons Math received in my previous rant against Commons Lang). Commons Math provides a lot of functionality that Uncommons Maths does not and probably never will.

The domain name that I use for my software is uncommons.org. The library does maths-type stuff. The name was obvious. Why “Maths” not “Math”? Because that’s what we call it here.

I looked at Commons Maths once and it didn’t meet my requirements (I can’t even remember what they were), which is why I chose not to use it, not because it was defective in any way. The only reason I ever mentioned Commons Math is because it was at that moment, after previous disappointments with some of the Apache Commons libraries, that I exclaimed “We don’t need common software, what we need is uncommon software!”. It was a statement of intent. Hence the domain name.

Uncommons Maths is a Java library consisting of a comprehensive random numbers package and other useful mathematical utility classes. It was originally part of the Watchmaker Framework for Evolutionary Computation but, due to its usefulness in other domains, it has now been converted into a standalone project (Apache Licence).

• Download
• API Documentation

This article briefly describes what’s available in this first public release. I am most definitely not a mathematician and, as such, this library is written by a programmer for programmers (but if mathematicians find it useful that’s good too). It includes classes that are useful in real world programs and is not intended to ever cover the full spectrum of mathematics. However, I hope that it will expand in scope over time in this spirit of pragmatism. To that end, suggestions and contributions are actively encouraged.

Random Number Generators

The Uncommons Maths library provides three easy-to-use, statistically-sound, high-performance pseudorandom number generators (RNGs). They are:

MersenneTwisterRNG

A Java port of the fast and reliable Mersenne Twister RNG originally developed by Makoto Matsumoto and Takuji Nishimura. This is faster¹ than java.util.Random and does not have the statistical flaws² of that RNG.

CellularAutomatonRNG

A Java port of Tony Pasqualoni’s ultra-fast Cellular Automaton RNG. It uses a 256-cell automaton to generate random values. To the best of my knowledge, this is the fastest¹ available pure Java RNG that completes the Diehard test suite without any problems.

AESCounterRNG

This is a cryptographically-strong³ non-linear RNG that is around 10x faster¹ than java.security.SecureRandom. Reverse-engineering the generator state from observations of its output would involve cracking the AES block cipher.

Probability Distributions

Using the included probability distribution wrappers, these RNGs (and the standard JDK ones) can be used to generate values from Uniform, Normal, Binomial, Poisson and Exponential distributions.

Permutations & Combinations

Uncommons Maths also includes generics-enabled combination and permutation generators. These are based on Java classes originally written by Michael Gilleland.

Statistics

Uncommons Maths provides a statistical data set class that can calculate a variety of descriptive statistics (variance, median, standard deviation, arithmetic and geometric means, etc.) for a set of values.

Other

Other useful features in Uncommons Maths include utility methods to complement those in java.lang.Math, and utility classes for manipulating binary data.