Two-dimensional test function \(f\) with $$f(\mathbf{x}) = (1 - 8 \mathbf{x}_1 + 7 \mathbf{x}_1^2 - 7/3 \mathbf{x}_1^3 + 1/4 \mathbf{x}_1^4)\mathbf{x}_2^2e^{-\mathbf{x}_2}$$ subject to \(0 \leq \mathbf{x}_1 \leq 5\) and \(0 \leq \mathbf{x}_2 \leq 6\).
makeHosakiFunction()[smoof_single_objective_function]
G. A. Bekey, M. T. Ung, A Comparative Evaluation of Two Global Search Algorithms, IEEE Transaction on Systems, Man and Cybernetics, vol. 4, no. 1, pp. 112- 116, 1974.