close all;
clear all;
clc;
f0=10; % Signalo daznis, kuris bus aproksimuojamas
x1=[0.1:1/60:1];
x2=[1:1/60:1];
harm1 = cos(pi*x1);
harm2 = sin(x2);
signa2 = harm1 + harm2;
harm3 = cos(x1+x2);
T = signa2 + harm3+ 3.5; %funkcija

plot(x1,T)
% Svorio koeficientai
w11=randn(1);
w12=randn(1);
w13=randn(1);
w14=randn(1);
w15=randn(1);
w16=randn(1);
w17=randn(1);
w18=randn(1);

w21=randn(1);
w22=randn(1);
w23=randn(1);
w24=randn(1);

w31=randn(1);
w32=randn(1);




b11=0.15;
b12=0.15;
b13=0.15;
b14=0.15;
b21=0.15;
b22=0.15;
b3=0.15;


nu = .2;
for j = 1:100
    for indx = 1:numel(x1)
        y11=w11*x1+w15*x2+b11;
        y12=w12*x1+w16*x2+b12;
        y13=w13*x1+w17*x2+b13;
        y14=w14*x1+w18*x2+b14;
        y21=1./(1+exp(-(w21*y11(indx)+w22*y12*+b21)));
        y22=1./(1+exp(-(w23*y11(indx)+w24*y12*+b22)));


        y3=1./(1+exp(-(w31*y21(indx)+w32*y22(indx)*+b3)))
        e = T(indx) - y3;


        Delta = e;
        w11 = w11 + nu*Delta*y11;
        w12 = w12 + nu*Delta*y12;
        w13 = w13 + nu*Delta*y13;
        w14 = w14 + nu*Delta*y14;
        w15 = w15 + nu*Delta*y11;
        w16 = w16 + nu*Delta*y12;
        w17 = w17 + nu*Delta*y13;
        w18 = w18 + nu*Delta*y14;

        w21 = w21 + nu*y21*(1-y21)*Delta*w21;
        w22 = w22 + nu*y22*(1-y22)*Delta*w22;
        w23 = w23 + nu*y21*(1-y23)*Delta*w23;
        w24 = w24 + nu*y22*(1-y24)*Delta*w22;

        w31 = w31 + nu*y3*(1-y3)*Delta*w31;
        w32 = w32 + nu*y3*(1-y3)*Delta*w32;


    end
end


y3 = zeros(1,numel(x));
for indx = 1:numel(x)
        y11=w11*x1+w15*x2+b11;
        y12=w12*x1+w16*x2+b12;
        y13=w13*x1+w17*x2+b13;
        y14=w14*x1+w18*x2+b14;
        y21=1./(1+exp(-(w21*y11(indx)+w22*y12*+b21)));
        y22=1./(1+exp(-(w23*y11(indx)+w24*y12*+b22)));


        y3=1./(1+exp(-(w31*y21(indx)+w32*y22(indx)*+b3)))
end

figure('Name','Pradiniai duomenys','NumberTitle','off');
plot(x1,T, x1,y3);%'kx');
xlabel('x_{[0.1...1]}');
ylabel('T(x)');
grid on;