Please help with Index exceeds matrix dimensions error

%%here is my code

clc; close all;

N=50;

x = zeros(1,N);

for n = 1:length(x)

    x(n)= sin((n/16)*pi);
end
y= zeros(1,N);
y(1)=-0.13;

for n = 2:length(x)

    y(n+1)=(-1/3)*x(n+2)+(1/2)*x(n+1)+(1/3)*x(n)+y(n);
end

stem(0:1:50, y, 'r-');

xlabel('n');

ylabel('y[n]');

title('Output y[n] of the system');

pause;

Answer 1

[Star Strider]

This will eliminate the error:

for n = 2:length(x)-2
    y(n+1)=(-1/3)*x(n+2)+(1/2)*x(n+1)+(1/3)*x(n)+y(n);
end

however you have to change the stem arguments accordingly:

stem(0:1:49, y, 'r-')

[Christopher Carey]

thank you very much would you mind explaining how this fixes it please, I am a beginner at MATLAB.

[Star Strider]

As always, my pleasure.

You are indexing x(n+2) in your code, and ‘x’ has only 50 elements. In order to avoid reading beyond the number of elements in ‘x’, you need to reduce the number of iterations by 2. Setting the iterations to 2:length(x)-2 accomplishes that, since ‘n’ now goes from 2 to 48.