public override bool eval_g(int n, double[] x, bool new_x, int m, double[] g) { g[0] = x[0] + x[1]; g[1] = x[0] * x[0] + x[1] * x[1]; g[2] = 9.0 * x[0] * x[0] + x[1] * x[1]; g[3] = x[0] * x[0] - x[1]; g[4] = x[1] * x[1] - x[0]; return true; }