matlab遗传算法函数代码
时间: 2023-09-16 08:15:47 浏览: 116
当然,我可以为你提供一个简单的 MATLAB 遗传算法函数代码示例:
```matlab
function [bestSolution, bestFitness] = geneticAlgorithm(populationSize, chromosomeLength, mutationRate, crossoverRate, numGenerations)
% 初始化种群
population = randi([0, 1], populationSize, chromosomeLength);
for generation = 1:numGenerations
% 计算适应度
fitness = calculateFitness(population);
% 选择父代
selectedParents = selection(population, fitness);
% 交叉操作
offspring = crossover(selectedParents, crossoverRate);
% 变异操作
mutatedOffspring = mutation(offspring, mutationRate);
% 合并父代和子代种群
combinedPopulation = [population; mutatedOffspring];
% 选择新的种群
population = elitismSelection(combinedPopulation, fitness, populationSize);
end
% 计算最佳个体和适应度
bestFitness = max(fitness);
bestSolution = population(find(fitness == bestFitness, 1), :);
end
function fitness = calculateFitness(population)
% 计算适应度,根据具体问题进行定义
fitness = sum(population, 2);
end
function selectedParents = selection(population, fitness)
% 轮盘赌选择方法
cumulativeFitness = cumsum(fitness);
totalFitness = sum(fitness);
randomNumbers = rand(size(population, 1), 1) * totalFitness;
selectedParents = zeros(size(population));
for i = 1:size(population, 1)
index = find(cumulativeFitness >= randomNumbers(i), 1);
selectedParents(i, :) = population(index, :);
end
end
function offspring = crossover(selectedParents, crossoverRate)
% 单点交叉操作
offspring = zeros(size(selectedParents));
for i = 1:2:size(selectedParents, 1)
if rand() < crossoverRate
crossoverPoint = randi([2, size(selectedParents, 2) - 1]);
offspring(i, :) = [selectedParents(i, 1:crossoverPoint), selectedParents(i + 1, crossoverPoint + 1:end)];
offspring(i + 1, :) = [selectedParents(i + 1, 1:crossoverPoint), selectedParents(i, crossoverPoint + 1:end)];
else
offspring(i, :) = selectedParents(i, :);
offspring(i + 1, :) = selectedParents(i + 1, :);
end
end
end
function mutatedOffspring = mutation(offspring, mutationRate)
% 每个基因位以一定概率进行变异
mutatedOffspring = offspring;
for i = 1:size(offspring, 1)
for j = 1:size(offspring, 2)
if rand() < mutationRate
mutatedOffspring(i, j) = ~mutatedOffspring(i, j);
end
end
end
end
function newPopulation = elitismSelection(combinedPopulation, fitness, populationSize)
% 精英选择,保留适应度最高的个体进入下一代种群
[~, sortedIndices] = sort(fitness, 'descend');
newPopulation = combinedPopulation(sortedIndices(1:populationSize), :);
end
```
这是一个简单的遗传算法函数代码,包含了种群初始化、适应度计算、选择、交叉、变异和精英选择等基本步骤。你可以根据具体问题对代码进行相应的修改和扩展。希望能对你有所帮助!
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