It’s been very nearly a year since the last release (0.4.3) of the Watchmaker Framework for Evolutionary Computation so, before 2008 disappears completely, it’s time for a new version that includes some of the stuff that I’ve been working on intermittently during this time.
Backwards-(In)compatibility
The primary purpose of the 0.5.0 release is to break backwards-compatibility and upset users. If you’re already using 0.4.3, there are two main changes that you need to be aware of:
Firstly, the StandaloneEvolutionEngine class has been renamed to ConcurrentEvolutionEngine. The old name did not reflect what distinguished this EvolutionEngine implementation from other implementations (some of which are yet to be added but will be in future releases). One such alternative is the new SequentialEvolutionEngine, which performs all work on the request thread and, as such, is useful in managed environments that do not permit control over threading.
Secondly, all methods and constructors that take probabilities as parameters now use the new Probability type rather than Java doubles. There was too much duplication of range-checking code and code that generated events with a given probability. All of this has now been encapsulated in one place.
Genetic Programming
The Watchmaker download includes source code for several example applications. New in this release is the tree-based genetic programming (GP) example. Genetic Programming is a type of evolutionary algorithm that involves evolving computer programs. The Watchmaker Framework is a general-purpose evolutionary computation framework. It does not include any GP-specific classes but there is nothing preventing you from applying it to the task of evolving program trees. This example is a Watchmaker-powered Java implementation of the first GP problem presented in Toby Segaran’s book, Programming Collective Intelligence. From a set of example inputs and outputs, it generates a program that encapsulates the formula for converting the inputs to the outputs.
Useful Links
- Project home page
- Full change log
- Download latest version
- API documentation
- Example applets: Travelling Salesman, Biomorphs, Sudoku
- Feedback: Issue tracker