Formula:
$$f(x) = 4x_1^2 - 2.1x_1^4 + \frac{x_1^6}{3} + x_1 x_2 - 4x_2^2 + 4x_2^4$$
Global minimum: \(f(\pm 0.0898, \mp 0.7126) \approx -1.0316\)
There are two global minima at approximately \((0.0898, -0.7126)\) and
\((-0.0898, 0.7126)\).
Characteristics:
Type: Multimodal
Separable: No
Differentiable: Yes
Fixed dimension: 2
Number of local minima: 6
Number of global minima: 2
Default bounds: \([-5, 5]^2\)
The function has a shape resembling a camel's back with six humps (minima).