matlab鲸鱼算法测试函数
时间: 2023-10-10 13:07:05 浏览: 51
鲸鱼算法(Whale Optimization Algorithm, WOA)是一种基于自然界鲸鱼捕食行为的优化算法。在MATLAB中,可以使用以下步骤编写一个简单的鲸鱼算法测试函数:
1. 首先,定义目标函数。这是您希望优化的函数。例如,我们可以使用Rosenbrock函数作为示例:
```matlab
function y = rosenbrock(x)
y = 100 * (x(2) - x(1)^2)^2 + (1 - x(1))^2;
end
```
2. 然后,编写鲸鱼算法的主要部分。这包括初始化鲸鱼群体、计算适应度、更新鲸鱼位置和选择新的鲸鱼位置等步骤。以下是一个简单的鲸鱼算法实现:
```matlab
function [best_whale, best_fitness] = whale_optimization()
% 初始化参数
population_size = 50; % 鲸鱼数量
generations = 100; % 迭代次数
max_iterations = 10^6; % 最大迭代次数
search_space = [-10, 10]; % 搜索空间范围
alpha = 0.5; % 学习因子
beta = 0.9; % 加速因子
gamma = 1.4; % 惯性权重
rho = 0.95; % 捕食系数
theta = 2 * pi / generations; % 捕食周期
% 初始化鲸鱼位置和适应度值
whales = init_whales(population_size, search_space); fitness = zeros(population_size, 1);
for i = 1:population_size
fitness(i) = rosenbrock(whales(i, :)');
end
best_fitness = min(fitness);
best_whale = whales(min(fitness), :);
old_fitness = best_fitness;
old_whale = best_whale;
% 迭代优化过程
for t = 1:generations
a = alpha * old_fitness + beta * abs(rand() - old_fitness); % 线性递减加速度项
r = randn(); % 随机扰动项
A = 2 * a * r - a; % A矩阵(捕食操作)
C = randn(); % C向量(捕食操作)
new_whales = update_whales(whales, A, C, search_space, max_iterations);
new_fitness = evaluate_fitness(new_whales, rosenbrock);
improved = new_fitness < old_fitness; % 如果适应度提高,则进行更新操作
if improved || (t > theta && abs(new_fitness - old_fitness) < abs(old_fitness - best_fitness)) % 如果满足终止条件,则输出结果并返回最优解
old_fitness = new_fitness;
old_whale = new_whales(find(new_fitness < best_fitness, 1), :);
if new_fitness < best_fitness
best_fitness = new_fitness;
best_whale = new_whales(find(new_fitness < best_fitness, 1), :);
end
end
whales = new_whales; % 更新鲸鱼群体状态