How to vectorize the for loop

Dear all,

I am trying to vectorize the following statement:

u=zeros(n,2,2);
v=zeros(N);
w=zeros(n,2,2);

for j=1:n
   u(j,1,1)=v(j)*w(j,1,1);
end

The vectorized version:

    j=1:n
    u(j,1,1)=v(j)*w(j,1,1);

But I got the error message:

Inner matrix dimensions must agree

because N>n.

Would you please suggest a way to resolve this problem? Thank you.

Answer 1

[Kelly Kearney]

 u(j,1,1) = v(j) .* w(j,1,1);

The .* means element-by-element multiplication; otherwise, it attempts matrix multiplication.