crosover.m

多智能体工具包

function chrom1=crosover(chrom,matenum)
% CROSSOVER	Mate two individuals. 

%     Copyright (c) 1998-2000 Jiming Liu and Jianbing Wu

mateind=[]; 
chrom1=chrom;
[pop bitlength]=size(chrom); 
ind=1:pop; 

u=floor(pop*matenum);
if floor(u/2)~=u/2
  u=u-1;
end
%select percentage to mate randomly

while length(mateind)~=u
  i=round(rand*pop);
  if i==0
    i=1;
  end
  if ind(i)~=-1
    mateind=[mateind i]; 
    ind(i)=-1;
  end
end

%perform dual point crossover 

for i=1:2:u-1
  Loop=0;
  IsLegal=0;
  while ~IsLegal
    MustAgain=0;
    while ~MustAgain
      splitpos=sort(floor(rand(1,2)*bitlength));  % crossover point
      for mm=1:2
        if splitpos(mm)==0
          splitpos(mm)=1; 
        end
      end
      if splitpos(1)~=splitpos(2)
        MustAgain=1;
      end
    end

    i1=mateind(i); 
    i2=mateind(i+1);
    tempgene=chrom(i1,splitpos(1)+1:splitpos(2));
    NewChromosome1=chrom(i1,:);
    NewChromosome2=chrom(i2,:);
    NewChromosome1(splitpos(1)+1:splitpos(2))=chrom(i2,splitpos(1)+...
                   1:splitpos(2));
    NewChromosome2(splitpos(1)+1:splitpos(2))=tempgene;
    IsLegal=forlegal(NewChromosome1);
    if IsLegal
      IsLegal=forlegal(NewChromosome2);
    end
    if IsLegal
      chrom1(i1,splitpos(1)+1:splitpos(2))=chrom(i2,splitpos(1)+1:...
               splitpos(2));
      chrom1(i2,splitpos(1)+1:splitpos(2))=tempgene;
    end

    Loop=Loop+1;           % avoid deadlock.
    if Loop>200
      break;
    end

  end
end