Difficult real-parameter (continuous) optimization problems appearing in academic, scientific, and industrial domains have been addressed by a variety of both metaheuristic and classical optimization techniques: evolutionary algorithms such as Evolution Strategies, Differential Evolution, and Particle Swarm Optimization, classical methods such as Quasi-Newton, Hybrid methods, and other non-evolutionary methods such as Simulated Annealing and Tabu Search, among others. In many of the related studies, a subset of the standard test problems (Sphere, Schwefel's, Rosenbrock's, Rastrigin's, etc.) has been considered, once they have been numerically treated to represent actually interesting problems (as done in standard bechnmarks such as: CEC’05, CEC0’08, BBOB’09, etc.).
The use of these standard functions allows the comparison of algorithms in the same conditions and with a common and systematic parameter setting.