select7.m

王小平《遗传算法——理论、应用与软件实现》随书光盘

function [out,coefs,pin]=select(in,d,x,y,h1,h2)
%
% out=select(in);
%
% selects a new population
%
%
global stop;
%
% Mix up the population
%
chrom=shuffle(in);

%
% Decode the existing population
%
coefs=decodall(chrom,d);

%
% Evaluate its' performance
%
pin=perf7(coefs,x,y,h1,1);


%
% Now work through the population to
% select the best.
% "Who's the hardest?" selection
%

[D L]=size(chrom);


for i = 1:2:D
	if stop == 1 
		break;
	end
	if pin(i)<pin(i+1)
		chrom(i+1,:)=chrom(i,:);
	else
		chrom(i,:)=chrom(i+1,:);
	end
end
coefs=decodall(chrom,d);
pin=perf7(coefs,x,y,h2,2);

out=chrom;