The Bartels Conn Function is defined as $$f(\mathbf{x}) = |\mathbf{x}_1^2 + \mathbf{x}_2^2 + \mathbf{x}_1\mathbf{x}_2| + |\sin(\mathbf{x}_1)| + |\cos(\mathbf{x})|$$ subject to \(\mathbf{x}_i \in [-500, 500]\) for \(i = 1, 2\).
makeBartelsConnFunction()[smoof_single_objective_function]