Reference: Mirjalili S, Mirjalili S M, Lewis A. Grey wolf optimizer[J]. Advances in Engineering Software, 2014, 69: 46-61.
Variables
Meaning
pop
The number of population
lb
List, the lower bound of the i-th component is lb[i]
ub
List, the upper bound of the i-th component is ub[i]
iter
The maximum number of iterations
dim
The dimension, dim = len(lb) = len(ub)
pos
List, the position of each wolf
score
List, the score of each wolf
iter_best
List, the best so-far score of each iteration
alpha_pos
List, the position of the alpha wolf
alpha_score
The score of alpha wolf
beta_pos
List, the position of the beta wolf
beta_score
The score of the beta wolf
delta_pos
List, the position of the delta wolf
delta_score
The score of the delta wolf
Test problem: Pressure vessel design
$$
\begin{align}
&\text{min}\ f(x)=0.6224x_1x_3x_4+1.7781x_2x_3^2+3.1661x_1^2x_4+19.84x_1^2x_3,\\
&\text{s.t.} \\
&-x_1+0.0193x_3\leq0,\\
&-x_3+0.0095x_3\leq0,\\
&-\pi x_3^2x_4-\frac{4}{3}\pi x_3^3+1296000\leq0,\\
&x_4-240\leq0,\\
&0\leq x_1\leq99,\\
&0\leq x_2 \leq99,\\
&10\leq x_3 \leq 200,\\
&10\leq x_4 \leq 200.
\end{align}
$$
if __name__ == '__main__' :
pop = 200
lb = [0 , 0 , 10 , 10 ]
ub = [99 , 99 , 200 , 200 ]
iter = 100
print (main (pop , lb , ub , iter ))
{
'best solution' : [1.3021065176429443 , 0.6432278697383198 , 67.39566614500494 , 10.432203586211408 ],
'best score' : 8087.875089101558
}