模拟退火法---飞机巡航问题

    clc, clear
    sj0=[53.7121   15.3046  51.1758    0.0322   46.3253   28.2753   30.3313    6.9348
    56.5432   21.4188   10.8198   16.2529   22.7891   23.1045   10.1584   12.4819
    20.1050   15.4562   1.9451    0.2057    26.4951   22.1221   31.4847    8.9640
    26.2418   18.1760   44.0356   13.5401   28.9836   25.9879   38.4722   20.1731
    28.2694   29.0011   32.1910    5.8699   36.4863   29.7284   0.9718   28.1477
    8.9586   24.6635    16.5618   23.6143   10.5597   15.1178   50.2111   10.2944
    8.1519    9.5325    22.1075   18.5569   0.1215   18.8726    48.2077   16.8889
    31.9499   17.6309   0.7732    0.4656    47.4134   23.7783   41.8671    3.5667
    43.5474    3.9061   53.3524   26.7256   30.8165   13.4595   27.7133    5.0706
    23.9222    7.6306   51.9612   22.8511   12.7938   15.7307   4.9568    8.3669
    21.5051   24.0909   15.2548   27.2111   6.2070    5.1442    49.2430   16.7044
    17.1168   20.0354   34.1688   22.7571   9.4402    3.9200    11.5812   14.5677
    52.1181    0.4088   9.5559   11.4219    24.4509    6.5634   26.7213   28.5667
    37.5848   16.8474   35.6619    9.9333   24.4654    3.1644   0.7775    6.9576
    14.4703   13.6368   19.8660   15.1224   3.1616    4.2428    18.5245   14.3598
    58.6849   27.1485   39.5168   16.9371   56.5089   13.7090   52.5211   15.7957
    38.4300    8.4648   51.8181   23.0159   8.9983   23.6440    50.1156   23.7816
    13.7909    1.9510   34.0574   23.3960   23.0624    8.4319   19.9857    5.7902
    40.8801   14.2978   58.8289   14.5229   18.6635    6.7436   52.8423   27.2880
    39.9494   29.5114   47.5099   24.0664   10.1121   27.2662   28.7812   27.6659
    8.0831   27.6705    9.1556   14.1304    53.7989    0.2199   33.6490    0.3980
    1.3496   16.8359    49.9816    6.0828   19.3635   17.6622   36.9545   23.0265
    15.7320   19.5697   11.5118   17.3884   44.0398   16.2635   39.7139   28.4203
    6.9909   23.1804    38.3392   19.9950   24.6543   19.6057   36.9980   24.3992
    4.1591    3.1853    40.1400   20.3030   23.9876    9.4030   41.1084   27.7149
    ];    %加载100个目标的数据，数据按照表格中的位置保存在纯文本文件sj.txt中
    x=sj0(:,[1:2:8]);x=x(:);
    y=sj0(:,[2:2:8]);y=y(:);
    sj=[x y]; d1=[70,40]; 
    sj=[d1;sj;d1]; sj=sj*pi/180; %角度化成弧度
    d=zeros(102); %距离矩阵d初始化
    for i=1:101
       for j=i+1:102
    d(i,j)=6370*acos(cos(sj(i,1)-sj(j,1))*cos(sj(i,2))*cos(sj(j,2))+sin(sj(i,2))*sin(sj(j,2)));
       end
    end
    d=d+d';
    path=[];long=inf; %巡航路径及长度初始化
    rand('state',sum(clock));  %初始化随机数发生器
    for j=1:1000  %求较好的初始解
    path0=[1 1+randperm(100),102]; temp=0;
    for i=1:101
        temp=temp+d(path0(i),path0(i+1));
    end
    if temp<long
        path=path0; long=temp;
    end
    end
    e=0.1^30;L=20000;at=0.999;T=1;
    for k=1:L  %退火过程
    c=2+floor(100*rand(1,2));  %产生新解
    c=sort(c); c1=c(1);c2=c(2);
      %计算代价函数值的增量
    df=d(path(c1-1),path(c2))+d(path(c1),path(c2+1))-d(path(c1-1),path(c1))-d(path(c2),path(c2+1));
      if df<0 %接受准则
      path=[path(1:c1-1),path(c2:-1:c1),path(c2+1:102)]; long=long+df;
      elseif exp(-df/T)>rand
      path=[path(1:c1-1),path(c2:-1:c1),path(c2+1:102)]; long=long+df;
      end
      T=T*at;
       if T<e
       break;
       end
    end
    path, long % 输出巡航路径及路径长度
    xx=sj(path,1);yy=sj(path,2);
    plot(xx,yy,'-*') %画出巡航路径
    
    
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
    
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