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[原创]史上最简洁易懂的模拟退火解TSP问题的Matlab源程序+过程图

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发表于 2006-1-26 07:07:56 | 显示全部楼层 |阅读模式
<>%this program is written by 刘学智. Finished time is 05.1.23 16:03 <BR>%utilizing it solving TSP problem by simulating stealing algorithm<BR>%[fval,route]=sa_tsp(d,10,0.1,.87)<BR>%d=[0 2 1 2 0 0 1 0 1 2 1 1 1 1<BR>%2 0 1 4 1 0 1 1 1 3 1 0 2 1<BR>%1 1 0 1 0 0 0 3 1 1 0 2 2 1<BR>%2 4 1 0 1 1 2 1 0 2 1 0 1 1<BR>%0 1 0 1 0 2 0 1 1 1 0 1 1 2<BR>%0 0 0 1 2 0 1 2 1 1 1 2 1 2<BR>%1 1 0 2 0 1 0 1 1 1 0 2 2 1<BR>%0 1 3 1 1 2 1 0 1 2 1 4 2 2<BR>%1 1 1 0 1 1 1 1 0 1 1 1 3 1<BR>%2 3 1 2 1 1 1 2 1 0 1 0 0 3<BR>%1 1 0 1 0 1 0 1 1 1 0 3 1 1<BR>%1 0 2 0 1 2 2 4 1 0 3 0 1 0<BR>%1 2 2 1 1 1 2 2 3 0 1 1 0 4<BR>%1 1 1 1 2 2 1 2 1 3 1 0 4 0];</P>
<>%the result is fval=2; route=14  9 4 13 10 12 2 6 3 11 7 5 1 8</P>
<>function [fval,route]=sa_tsp(d,t0,tf,alpha)<BR>%d is the distance matrix;t0,tf is the initial and finil temperature;<BR>%alpha is controling temperature coeffient<BR>n=length(d);%the number of cities<BR>L=100*n;%the length of Markov chain<BR>route=randperm(n);%the initial traveling route<BR>fval=value(route,d);%the initial goal value<BR>t=t0;ii=0;<BR>tic<BR>while t&gt;tf<BR>    for i=1<BR>        [fval_after,route_after]=exchange(route,d);<BR>        if fval_after&lt;fval<BR>           route=route_after;<BR>           fval=fval_after;<BR>        elseif exp((fval-fval_after)*2/t)&gt;rand<BR>               route=route_after;<BR>               fval=fval_after;<BR>        else route=route;<BR>             fval=fval;<BR>        end<BR>    end<BR>    t=alpha*t;<BR>    ii=ii+1;fval_sequence(ii)=fval;<BR>end<BR>plot(1:ii,fval_sequence);%plot the convergence figure<BR>toc<BR>%----------------------------------------------------------------<BR>function fval=value(route,d)%used for reckoning the goal value of the selected traveling route<BR>n=length(d);<BR>fval=0;<BR>for i=1:n-1<BR>    fval=fval+d(route(i),route(i+1));<BR>end<BR>%fval=fval+d(route(n),route(1));% if'%'is omited,it computes a circle,else<BR>%a chain------------------------------------------------------------------<BR>function [fval_after,route_after]=exchange(route,d)<BR>%changing traveling route by inversing the sequence between two selected 2 locations <BR>n=length(d);<BR>location1=ceil(n*rand);<BR>location2=ceil(n*rand);%the location of two exchanged number<BR>loc1=min(location1,location2);loc2=max(location1,location2);<BR>middle_route=fliplr(route(loc1:loc2));%the part route which has been exchanged<BR>route_after=[route(1:loc1-1) middle_route route(loc2+1:n)];%the after traveling route<BR>fval_after=value(route_after,d);<BR>%----------------------------------------------------------------</P>
 楼主| 发表于 2006-1-26 07:09:51 | 显示全部楼层
QQ:137278541 <BR>验证:mcm
 楼主| 发表于 2006-1-26 07:12:11 | 显示全部楼层
<>遗传程序接着上传</P>
发表于 2011-4-16 18:57:17 | 显示全部楼层
好好学习下
发表于 2011-4-16 19:01:04 | 显示全部楼层
好好学习下
发表于 2011-6-8 20:52:48 | 显示全部楼层
借鉴了 楼主辛苦了
发表于 2011-9-5 17:16:11 | 显示全部楼层
楼主辛苦了……
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