Traveling Sales Problem (TSP)_Genetic Algorithm

Traveling Sales Problem (TSP)_Genetic Algorithm

function [R,Rlength]=geneticTSP(D,n,C,m,alpha)

[N,NN]=size(D);
farm=zeros(n,N);
for i=1:n
farm(i,:)=randperm(N);
end
R=farm(1,:); 
len=zeros(n,1);
fitness=zeros(n,1);
counter=0;

while counter
for i=1:n
len(i,1)=myLength(D,farm(i,:));
end
maxlen=max(len);
minlen=min(len);
fitness=fit(len,m,maxlen,minlen);
rr=find(len==minlen);
R=farm(rr(1,1),:);

FARM=farm;
nn=0;
for i=1:n
if fitness(i,1)>=alpha*rand
nn=nn+1;
FARM(nn,:)=farm(i,:);
end
end
FARM=FARM(1:nn,:);

[aa,bb]=size(FARM);
while aaif nn<=2
nnper=randperm(2);
else
nnper=randperm(nn);
end
A=FARM(nnper(1),:);
B=FARM(nnper(2),:);
[A,B]=intercross(A,B);
FARM=[FARM;A;B];
[aa,bb]=size(FARM);
end
if aa>n
FARM=FARM(1:n,:);
end

farm=FARM;
clear FARM
counter=counter+1

end

Rlength=myLength(D,R);

function [a,b]=intercross(a,b)
L=length(a);
if L<=10 
W=1;
elseif ((L/10)-floor(L/10))>=rand&&L>10
W=ceil(L/10);
else 
W=floor(L/10);
end
p=unidrnd(L-W+1);
for i=1:W 
x=find(a==b(1,p+i-1));
y=find(b==a(1,p+i-1));
[a(1,p+i-1),b(1,p+i-1)]=exchange(a(1,p+i-1),b(1,p+i-1));
[a(1,x),b(1,y)]=exchange(a(1,x),b(1,y)); 
end
function [x,y]=exchange(x,y)
temp=x;
x=y;
y=temp;


function len=myLength(D,p)
[N,NN]=size(D);
len=D(p(1,N),p(1,1));
for i=1:(N-1)
len=len+D(p(1,i),p(1,i+1));
end


function fitness=fit(len,m,maxlen,minlen)
fitness=len;
for i=1:length(len)
fitness(i,1)=(1-((len(i,1)-minlen)/(maxlen-minlen+0.000001))).^m;
end