I was fortunate enough to be offered a summer project scholarship by the University of Waikato. Under the supervision of Professor Eibe Frank I contributed three different subprojects:
The biggest project was the unification of three different domain specific languages (DSL)
in expressionlanguage. I unified three existing DSLs into one using an improved design
and added some major performance optimizations.
Next, I implemented the PAA & SAX transformation in timeseries.
This implementation is more general than existing implementations (at that time).
Lastly, I changed the implementation for the computation of the standard deviation
in stddev.
The previous implementation had numerical stability issues which I discovered when
testing the PAA & SAX transformation.
Additionally, I generated very hard test cases with Python's unlimited precision fractions.