写一个matlab基于鲸鱼算法求解有起点的带容量的车辆路径问题的代码
时间: 2024-03-03 18:47:10 浏览: 59
以下是一个基于鲸鱼算法求解有起点的带容量的车辆路径问题的Matlab代码。这个代码使用了TSP(旅行商问题)作为例子,但是可以通过修改一些参数来适应带容量车辆路径问题。
```
% 定义鲸鱼算法的参数
whale_num = 10; % 鲸鱼的数量
max_iter = 100; % 最大迭代次数
a = 2; % 控制参数
b = 0.5; % 控制参数
% 定义TSP问题的参数
city_num = 50; % 城市数量
capacity = 100; % 车辆容量
demand = 1 + floor(9*rand(city_num-1,1)); % 需求量
distance_matrix = rand(city_num) + eye(city_num); % 距离矩阵
% 初始化鲸鱼位置和速度
position = rand(whale_num,city_num+1)*city_num;
velocity = rand(whale_num,city_num+1)*city_num;
% 迭代寻找最优解
best_solution = zeros(max_iter,1); % 存储每次迭代的最优解
best_route = zeros(max_iter,city_num); % 存储每次迭代的最优路径
for iter = 1:max_iter
% 计算每只鲸鱼的适应度值
fitness = zeros(whale_num,1);
for whale = 1:whale_num
route = position(whale,:);
route(route == 0) = [];
if length(route) > 1
% 计算路径长度
d = 0;
for i = 1:length(route)-1
d = d + distance_matrix(route(i),route(i+1));
end
% 计算路径是否符合容量限制
load = 0;
for i = 2:length(route)
load = load + demand(route(i)-1);
if load > capacity
d = Inf;
break;
end
end
fitness(whale) = 1/d;
end
end
% 寻找最优解和路径
[best_fitness,index] = max(fitness);
best_route(iter,:) = position(index,:);
best_solution(iter) = 1/best_fitness;
% 更新鲸鱼位置和速度
for whale = 1:whale_num
route = position(whale,:);
route(route == 0) = [];
if length(route) == 1
% 随机选择一个城市作为起点
current = route(1);
unvisited = 1:city_num;
unvisited(current) = [];
next = unvisited(randi(city_num-1));
position(whale,2:end) = next;
else
% 计算鲸鱼的新位置和速度
r1 = rand;
r2 = rand;
A = 2*a*r1 - a;
C = 2*r2;
route_best = best_route(iter,:);
route_best(route_best == 0) = [];
route_current = route;
route_current(route_current == 0) = [];
X1 = route_current;
X2 = route_best;
X3 = position(randi(whale_num),:);
velocity(whale,:) = abs(X1 - position(whale,:)) .* exp(b .* A) .* sin(2 .* pi .* A) + ...
abs(X2 - position(whale,:)) .* exp(b .* A) .* sin(2 .* pi .* A) + ...
abs(X3 - position(whale,:)) .* exp(b .* A) .* sin(2 .* pi .* A);
position(whale,:) = position(whale,:) + velocity(whale,:);
% 随机选择一个城市作为下一个节点
current = route(end);
unvisited = 1:city_num;
unvisited(current) = [];
next = unvisited(randi(city_num-1));
position(whale,end) = next;
end
end
end
% 绘制最优路径
best_route(best_route == 0) = [];
figure;
plot(best_route,'-o');
title('Best Route');
% 绘制最优解收敛曲线
figure;
plot(best_solution);
title('Best Solution Convergence');
```
需要注意的是,这个代码只是一个示例,需要根据实际问题进行修改和调整。特别是在定义TSP问题的参数时,需要根据实际情况进行设置。
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