F4 Benchmark where both PSO and Differential Evolution do better than Hill Climber

Figure 4 from:
Evolving Problems to Learn about Particle Swarm and other Optimisers W. B. Langdon and Riccardo Poli in Proceedings of the 2005 IEEE Congress on Evolutionary Computation, CEC 2005, volume 1, pp81-88, 2-5 September, Edinburgh, UK.
paper.
Java code
gnuplot script

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W.B.Langdon 21 Feb 2006