蚁群算法matlab代码
时间: 2023-11-25 16:38:31 浏览: 70
蚁群算法matlab代码.zip
这里是一个简单的蚁群算法的Matlab代码示例:
```matlab
% 蚁群算法求解TSP问题
% 城市坐标
city = [0.4000 0.4439
0.2439 0.1463
0.1707 0.2293
0.2293 0.7610
0.5171 0.9414
0.8732 0.6537
0.6878 0.5219
0.8488 0.3609
0.6683 0.2536
0.6195 0.2634];
% 城市数量
numCities = size(city, 1);
% 生成初始蚂蚁位置
antPosition = zeros(numCities, 1);
for i = 1:numCities
antPosition(i) = i;
end
% 设置参数
alpha = 1;
beta = 3;
q0 = 0.9;
rho = 0.1;
Q = 1;
maxIter = 100;
% 初始化信息素
pheromone = ones(numCities, numCities);
% 迭代寻优
for iter = 1:maxIter
% 蚂蚁走路
antPath = zeros(numCities, 1);
antPath(1) = antPosition(1);
for i = 2:numCities
% 计算选择概率
p = pheromone(antPosition(i-1), :) .^ alpha .* ((1 ./ city(:, 1)) .^ beta);
p(antPath) = 0;
p = p ./ sum(p);
% 轮盘赌选择下一个城市
if rand() < q0
[~, index] = max(p);
else
index = rouletteWheelSelection(p);
end
antPath(i) = index;
end
% 计算路径长度
len = 0;
for i = 1:numCities-1
len = len + norm(city(antPath(i), :) - city(antPath(i+1), :));
end
len = len + norm(city(antPath(numCities), :) - city(antPath(1), :));
% 更新信息素
deltaPheromone = zeros(numCities, numCities);
for i = 1:numCities-1
deltaPheromone(antPath(i), antPath(i+1)) = deltaPheromone(antPath(i), antPath(i+1)) + Q / len;
end
deltaPheromone(antPath(numCities), antPath(1)) = deltaPheromone(antPath(numCities), antPath(1)) + Q / len;
pheromone = (1 - rho) .* pheromone + deltaPheromone;
end
% 打印最优路径
[~, index] = min(pheromone(:));
[row, col] = ind2sub(size(pheromone), index);
path = [row, col];
for i = 1:numCities-2
[~, index] = max(pheromone(col, :));
path = [path, index];
col = index;
end
disp(path);
```
这份代码实现了一个简单的蚁群算法来求解TSP问题。其中,城市坐标存储在一个二维数组`city`中,`alpha`和`beta`分别为信息素和城市距离的权重,`q0`为选择最优路径的概率,`rho`为信息素挥发速率,`Q`为信息素增量系数,`maxIter`为最大迭代次数。在迭代过程中,程序会随机生成初始蚂蚁位置,然后进行蚂蚁走路,并通过更新信息素来优化路径。最终,程序会输出最优路径。
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