【路径规划】模拟退火之求解VRP问题【Matlab 025期】

一、源代码

clc;
clear;
close all;
 
T0 = 0.4 ; % initial temperature
r = 0.997 ;%0.997 ; % temperature damping rate
Ts = 0.001 ; % stop temperature
iter = 300;
 
model = initModel();
set(gcf,'unit','normalized','position',[0,0.35,1,0.7]);
 
flag = 0;
 
% initialization
 
load ini2.txt
route = ini2;
 
%route = randomSol(model);
while(1)
if(isFeasible(route,model)) 
    break; 
end
mode = randi([1 3]);
route = createNeibor(route,model,mode);
end
 
cost = calculateCost(route,model);
T = T0;
 
cnt = 1;
minCost = cost;
minRoute = route;
    
maxIterate = 2100;
costArray = zeros(maxIterate,1);
 
% SA
while(T > Ts)
    for k = 1:iter
    mode = randi([1 3]);
    newRoute = createNeibor(route,model,mode);
    newCost = calculateCost(newRoute,model);
    delta = newCost(4) - cost(4);
    
    if(delta < 0)
        cost = newCost;
        route = newRoute;
    else
        p=exp(-delta/T);
        if rand() <= p 
             cost = newCost;
             route = newRoute;
             
        end
    end
    end
    
    costArray(cnt) = cost(4);
    if cost(4)<minCost(4)
        minCost = cost;
        minRoute = route;
        flag = 1;
    end
    
    T = T*r; %  annealing
    disp(['Iteration ' num2str(cnt) ': BestCost = ' num2str(minCost) ': CurrentCost = ' num2str(cost) ' T = ' num2str(T)]);
    cnt = cnt+1;
    
   figure(1);
   if(flag == 1)
   plotSolution(minRoute,model);
    flag = 0;
   end
%    figure(2);
   subplot(1,2,2)
   plot(costArray);
 
   pause(0.0001);
end
 
plotSolution(minRoute,model);

二、备注

【路径规划】模拟退火之求解VRP问题【Matlab 025期】

一、源代码

二、备注

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