MATLAB: To simulate the SIMULINK model on MATLAB

MATLABsimulinksinusoidal generator

I have been trying yo simulate the current SIMULINK block to a MATLAB program.
I got this result.
I have tried to simulate the same wave using MATLAB but I got the below results. I can't understand why for the similar integrators the simulated wave seems different. Is there any better way to to get the same simulink result on MATLAB??
clc;
clear all; 
close all;
%Matlab program for a resonator 
w=3; %Frequency in radians
Gain=-1; %Gain of the resonator
K1=1; %Gain of integrator 1
K2=1; %Gain of integrator 2
T=0.01; %Sample Time
%Define input and output of the resonator
n=0:T:20;
y1=zeros(1,length(n));
y2=zeros(1,length(n));
x1=zeros(1,length(n));
x2=zeros(1,length(n));
u1=zeros(1,length(n));
u2=zeros(1,length(n));
u1(1:length(n))=w*Gain;
x1(1)=1; x2(1)=0;
%y1(1)=1; y2(1)=0;
for i=1:1:length(n)
    %Backward Euler method (Integrator 1)
    for n1=1:1:length(n)
        y1(n1)=x1(n1)+K1*T*u1(n1);
        x1(n1+1)=y1(n1);
    end
    u2(1:length(n))=y1*w; %Input to Integrator 2
    %Forward Euler method (Integrator 2)
    for n2=1:1:length(n)
        y2(n2)=x2(n2);
        x2(n2+1)=x2(n2)+K2*T*u2(n2);
    end
    u1(1:length(n))=Gain*y2; %Input to Integrator 1
end
plot(n,y1,'ro',n,y2,'bo');
xlabel('Time(seconds)');
ylabel('Amplitude');
title('Sine and Cosine of the resonator');
legend('Integrator 1 (Backward Euler)','Integrator 2 (Forward Euler)');
grid on;

Best Answer

The following loop seems to do it:
for i=1:1:length(n)
    %Backward Euler method (Integrator 1)
    for n1=1:1:length(n)
        y1(n1)=x1(n1)+K1*T*u1(n1)*w;
        x1(n1+1)=y1(n1);
    end
    u2(1:length(n))= y1; %Input to Integrator 2
    %Forward Euler method (Integrator 2)
    for n2=1:1:length(n)
        y2(n2)=x2(n2);
        x2(n2+1)=x2(n2)+K2*T*u2(n2)*w;
    end
    u1(1:length(n))=Gain*y2; %Input to Integrator 1
end
plot(n,y1,'r',n,y2,'b');
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