Single-objective two-dimensional test function. The formula is given as $$f(\mathbf{x}) = (\mathbf{x}_1 + 10)^2 + (\mathbf{x}_2 + 10)^2 + exp(-\mathbf{x}_1^2 - \mathbf{x}_2^2)$$ subject to the constraints \(\mathbf{x}_i \in [-10, 10], i = 1, 2.\)
makeBrentFunction()[smoof_single_objective_function]
F. H. Branin Jr., Widely Convergent Method of Finding Multiple Solutions of Simul- taneous Nonlinear Equations, IBM Journal of Research and Development, vol. 16, no. 5, pp. 504-522, 1972.