给出粒子群算法改进的遗传算法matlab代码
时间: 2023-07-23 10:12:30 浏览: 100
以下是一个简单的粒子群算法改进的遗传算法的 MATLAB 代码示例:
```matlab
% 遗传算法参数
populationSize = 50; % 种群大小
chromosomeLength = 10; % 染色体长度
mutationRate = 0.01; % 变异率
tournamentSize = 5; % 锦标赛选择中的竞争个体数量
maxGenerations = 100; % 最大迭代次数
% 粒子群算法参数
particleSize = populationSize; % 粒子数量
inertiaWeight = 0.8; % 惯性权重
cognitiveWeight = 2; % 认知权重
socialWeight = 2; % 社会权重
% 初始化种群和粒子位置
population = randi([0, 1], populationSize, chromosomeLength);
particles = population;
% 初始化速度和个体历史最优位置
velocities = zeros(size(particles));
personalBests = particles;
% 计算适应度值
fitness = calculateFitness(population);
% 初始化全局最优位置和适应度值
globalBest = particles(fitness == max(fitness), :);
globalFitness = max(fitness);
% 迭代优化过程
for generation = 1:maxGenerations
% 遗传算法操作
parents = tournamentSelection(population, fitness, tournamentSize);
offspring = crossover(parents);
offspring = mutation(offspring, mutationRate);
% 更新种群
population = [parents; offspring];
% 更新适应度值
fitness = calculateFitness(population);
% 更新个体历史最优位置
for i = 1:particleSize
if fitness(i) > calculateFitness(personalBests(i, :))
personalBests(i, :) = particles(i, :);
end
end
% 更新全局最优位置
[maxFitness, index] = max(fitness);
if maxFitness > globalFitness
globalBest = particles(index, :);
globalFitness = maxFitness;
end
% 粒子群算法操作
r1 = rand(size(particles));
r2 = rand(size(particles));
velocities = inertiaWeight * velocities + cognitiveWeight * r1 .* (personalBests - particles) + socialWeight * r2 .* (globalBest - particles);
particles = particles + velocities;
% 边界约束处理
particles(particles < 0) = 0;
particles(particles > 1) = 1;
end
% 输出全局最优解
disp('Global Best Solution:');
disp(globalBest);
% 适应度函数示例(此处为一个简单的多峰函数)
function fitness = calculateFitness(population)
fitness = sum(population, 2);
end
% 锦标赛选择函数
function parents = tournamentSelection(population, fitness, tournamentSize)
parents = zeros(size(population));
for i = 1:size(population, 1)
competitors = randperm(size(population, 1), tournamentSize);
[~, index] = max(fitness(competitors));
parents(i, :) = population(competitors(index), :);
end
end
% 单点交叉函数
function offspring = crossover(parents)
offspring = zeros(size(parents));
for i = 1:2:size(parents, 1)
crossoverPoint = randi([1, size(parents, 2)]);
offspring(i, :) = [parents(i, 1:crossoverPoint), parents(i+1, crossoverPoint+1:end)];
offspring(i+1, :) = [parents(i+1, 1:crossoverPoint), parents(i, crossoverPoint+1:end)];
end
end
% 变异函数
function mutatedOffspring = mutation(offspring, mutationRate)
mutatedOffspring = offspring;
for i = 1:size(mutatedOffspring, 1)
for j = 1:size(mutatedOffspring, 2)
if rand < mutationRate
mutatedOffspring(i, j) = 1 - mutatedOffspring(i, j);
end
end
end
end
```
请注意,这只是一个示例代码,适应度函数是一个简单的多峰函数。你可以根据你的具体问题和适应度函数进行相应的修改和调整。此外,该代码中的遗传算法和粒子群算法的参数也可以根据你的需求进行调整。
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