N-D Test Functions G¶Gear objective function.
This class defines the Gear global optimization problem. This is a multimodal minimization problem defined as follows:

with 
 for 
.
Global optimum: 
 for 
, where the various 
 may be permuted.
Gavana, A. Global Optimization Benchmarks and AMPGO
Giunta objective function.
This class defines the Giunta global optimization problem. This is a multimodal minimization problem defined as follows:
![f_{\text{Giunta}}({x}) = 0.6 + \sum_{i=1}^{n} \left[\sin^{2}\left(1
- \frac{16}{15} x_i\right) - \frac{1}{50} \sin\left(4
- \frac{64}{15} x_i\right) - \sin\left(1
- \frac{16}{15} x_i\right)\right]](_images/math/4374e558e6065677c2ee0afeaf9bd4cba642a2e1.png)
with 
 for 
.
Two-dimensional Giunta function
Global optimum: 
 for
![x = [0.4673200277395354, 0.4673200169591304]](_images/math/89cb8452123689e3ee14273be49b54cddc46f18f.png)
Jamil, M. & Yang, X.-S. A Literature Survey of Benchmark Functions For Global Optimization Problems Int. Journal of Mathematical Modelling and Numerical Optimisation, 2013, 4, 150-194.
Todo
Jamil has the wrong fglob. I think there is a lower value.
Goldstein-Price objective function.
This class defines the Goldstein-Price global optimization problem. This is a multimodal minimization problem defined as follows:
![f_{\text{GoldsteinPrice}}(x) = \left[ 1 + (x_1 + x_2 + 1)^2 
(19 - 14 x_1 + 3 x_1^2 - 14 x_2 + 6 x_1 x_2 + 3 x_2^2) \right]
\left[ 30 + ( 2x_1 - 3 x_2)^2 (18 - 32 x_1 + 12 x_1^2
+ 48 x_2 - 36 x_1 x_2 + 27 x_2^2) \right]](_images/math/3c53b30727dfc8fa219351bfa22e97658efea956.png)
with 
 for 
.
Two-dimensional GoldsteinPrice function
Global optimum: 
 for ![x = [0, -1]](_images/math/68400534f0e7c91bc69e01ba40b0f700447e106e.png)
Jamil, M. & Yang, X.-S. A Literature Survey of Benchmark Functions For Global Optimization Problems Int. Journal of Mathematical Modelling and Numerical Optimisation, 2013, 4, 150-194.
Gramacy Lee objective function No 2.
Two-dimensional GramacyLee02 function
Gramacy Lee objective function No 3.
Two-dimensional GramacyLee03 function
Griewank objective function.
This class defines the Griewank global optimization problem. This is a multimodal minimization problem defined as follows:

Here, 
 represents the number of dimensions and
 for 
.
Two-dimensional Griewank function
Global optimum: 
 for 
 for

Jamil, M. & Yang, X.-S. A Literature Survey of Benchmark Functions For Global Optimization Problems Int. Journal of Mathematical Modelling and Numerical Optimisation, 2013, 4, 150-194.
Gulf objective function.
This class defines the Gulf global optimization problem. This is a multimodal minimization problem defined as follows:

Where, in this exercise:
![t_i = i/100 \
y_i = 25 + [-50 \log(t_i)]^{2/3}](_images/math/39221cf69807e63b7d7fe6a258bf8eda957ef7c2.png)
with 
 for 
.
Global optimum: 
 for ![x = [50, 25, 1.5]](_images/math/c924032329378f153db4ead945f8e838bf77e361.png)
Gavana, A. Global Optimization Benchmarks and AMPGO
Todo
Gavana has absolute of (u - x[1]) term. Jamil doesn’t... Leaving it in.