Multiply 4D array with 2D array without a for loop

I want to compute this:

      for i=1:4
      f = f+ norm(reshape(i2k(S(:,:,1,i) .* C,[1,2]) - b(:,:,1,i),[sz^2 1]) ,2)^2; 
      end

Without a for loop. Because we square the norm we can do that:

sum(abs(i2k(S(:,:,1,:) .* C,[1,2])-b(:,:,1,:)).^2);

But I get an error when I do this

S(:,:,1,:) .* C,[1,2]

Can somebody tell me how this is done correctly?

Answer 1

[KL]

Try this,

 bsxfun(@times,S(:,:,1,:),C)

but remember, the result you'll get as a 3D matrix.