www.pudn.com > GA.rar > AdapGA.m, change:2008-09-10,size:2579b


function [xv,fv]=AdapGA(fitness,a,b,NP,NG,Pc1,Pc2,Pm1,Pm2,eps) 
%ӦŴ㷨 
L = ceil(log2((b-a)/eps+1)); 
 
x = zeros(NP,L); 
 
for i=1:NP 
     
    x(i,:) = Initial(L); 
     
    fx(i) = fitness(Dec(a,b,x(i,:),L)); 
     
end 
 
for k=1:NG 
     
    sumfx = sum(fx); 
     
    Px = fx/sumfx; 
 
    PPx = 0; 
     
    PPx(1) = Px(1); 
     
    for i=2:NP 
         
        PPx(i) = PPx(i-1) + Px(i); 
         
    end 
 
    for i=1:NP 
         
        sita = rand(); 
         
        for n=1:NP 
             
            if sita <= PPx(n) 
                 
                SelFather = n; 
                 
                break; 
                 
            end 
             
        end 
         
        Selmother = round(rand()*(NP-1))+1; 
         
        posCut = round(rand()*(L-2)) + 1; 
           
        favg = sumfx/NP; 
         
        fmax = max(fx); 
         
        Fitness_f = fx(SelFather); 
         
        Fitness_m = fx(Selmother); 
         
        Fm = max(Fitness_f,Fitness_m); 
         
        if Fm>=favg 
             
            Pc = Pc1*(fmax - Fm)/(fmax - favg); 
             
        else 
             
            Pc = Pc2; 
             
        end 
         
        r1 = rand(); 
         
        if r1<=Pc 
             
            nx(i,1:posCut) = x(SelFather,1:posCut); 
             
            nx(i,(posCut+1):L) = x(Selmother,(posCut+1):L); 
             
            fmu = fitness(Dec(a,b,nx(i,:),L)); 
 
            if fmu>=favg 
 
                Pm = Pm1*(fmax - fmu)/(fmax - favg); 
 
            else 
 
                Pm = Pm2; 
 
            end 
             
            r2 = rand(); 
             
            if r2 <= Pm 
                 
                posMut = round(rand()*(L-1) + 1); 
                 
                nx(i,posMut) = ~nx(i,posMut); 
                 
            end 
             
        else 
             
            nx(i,:) = x(SelFather,:); 
             
        end 
         
    end 
 
    x = nx; 
     
    for i=1:NP 
         
        fx(i) = fitness(Dec(a,b,x(i,:),L)); 
         
    end 
     
end 
 
fv = -inf; 
 
for i=1:NP 
     
    fitx = fitness(Dec(a,b,x(i,:),L)); 
     
    if fitx > fv 
         
        fv = fitx; 
         
        xv = Dec(a,b,x(i,:),L); 
         
    end 
     
end 
 
function result = Initial(length) 
 
for i=1:length   
     
    r = rand(); 
     
    result(i) = round(r);    
     
end 
 
function y = Dec(a,b,x,L) 
 
base = 2.^((L-1):-1:0); 
 
y = dot(base,x); 
 
y = a + y*(b-a)/(2^L-1);