GOLDEN SEARCH METHOD

GOLDEN SEARCH METHOD

Mencari Nilai Minimum dr Fungsi berikut :

f(x)=x^2/10-2*sin(x)

Kode Matlab :

%Golden Search Method

syms x

A = (x^2/10)-(2*sin(x)); %fungsi yg dicari nilai maksimum

a = 0; %nilai awal xl

b = pi/2;

e = 0.5;

t = (sqrt(5)-1/2);

x1 = a+t*(b-a);

x2 = b-t*(b-a);

n = 100;

N = [];

for i = 1:n

    fa = subs (A,x,x1);

    fb = subs (A,x,x2);

    if fa>fb

    a = x2;

    x2 = x1;

    x1 = a+t*(b-a);

    else

        b = x1;

        x1 = x2;

        x2 = b-t*(b-a);

    end

    N = [N; i a b x1 x2 fa fb];

    if abs (b-a)<= e

        break

    end

end

N

nilai_x = (b+a)/2

f_minimum = subs (A,x,nilai_x)

plot (N(:,1),N(:,7),'-ro','linewidth',3,...

'MarkerEdgeColor','y',...

'MarkerFaceColor','w',...

'MarkerSize',1.5)

title('Golden Seacrh Method','fontname','algerian')

xlabel('Sumbu Y','fontname','algerian')

ylabel('Sumbu X','fontname','algerian')

grid