The Schwefel benchmark test consists of a continuous, non-convex and multimodal function with a global best solution at the boundary of the search space with a minimum value of f (420.9687, ..., 420.9687) = 0. Contrary to Rastrigin's or Ackley's function, the Schwefel function is less symmetric and does not provide an overall guiding slope towards the global minimum. In the search for the global minimum, the CPSO approach demonstrates superior performance with respect to the other optimisation routines due to its high swarm diversity.