MATLAB: Matrix loop multiplication warning

matrix loop

Hello,

I have this code:

n=1;

Eout=zeros(4096,2);

while n<=4096

E=[Eopt(n); 0]; coupler=[sqrt(0.9) 1i*sqrt(0.1);1i*sqrt(0.1) sqrt(0.9)];

Eout(n)=coupler*E;

n=n+1;

end

I would like to have the various n results from Eout (a 2×1 matrix) in 4096×2 matrix. However, when i run this code this warning appears:

??? In an assignment A(I) = B, the number of elements in B and I must be the same.

Error in ==> Sim42 at 62

What should i do?

Thanks

Try:

Eout(n,:)=coupler*E;

though I can't tell if that is the only problem with the code you posted.

Which line is actually giving the error? Is it that line or the one above which also may be suspect depending what Eopt is.

No, you are multiplying a 2x2 matrix with a scalar, the first element of E.

Did you mean?

Eout = coupler * E;

One of ways

n=1;
k=[1 2 3 4;5 6 7 8];
out = zeros([size(k),3]);
while n<4
    k=k*n;
    out(:,:,n) = k;
    n=n+1;
end