For loop not working. Array indices must be positive integers or logical values.

Im Trying to implement an FIR difference equation where the output y is the average sum of a set number of values(M) of the input(x).

f0=10;
fs= 2*50*f0;
ts=1/fs;
tw=2;
t=0:ts:tw;
x=1*square(2*pi*f0*t);

y = zeros(1,length(x));
k=6;
M=k;
for i=1:k
    for j = 1:M
     y(j) = y +(1/(M+1))*x(i-j);
    end 
end
figure, plot(t,y, 'k')
ylim([-1 1])

Answer 1

[James Tursa]

This line on the first iteration when i=1 and j=1:

y(j) = y +(1/(M+1))*x(i-j);

You are indexing x(0). Also, you are trying to assign a vector (y on the rhs) into an element y(j) which isn't going to work either. This needs to be fixed.