How to multiply a window function to one dimension?

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John on 6 Jun 2014
Edited: John on 16 Jun 2014
Here is a Matlab script to apply a fixed window function along one dimension. Although it works, but is not elegant as a Matlab script. Can it be made more elegant? Thanks.
[L1, L2, L3, L4, L5, L6] = size(fids);
for n1=1:L1
for n3=1:L3
for n4=1:L4
for n5=1:L5
for n6=1:L6
fids(n1,:,n3,n4,n5,n6) = fids(n1,:,n3,n4,n5,n6) .* window;
end
end
end
end
end
Where window is a vector with the size equal to L2.
Image Analyst on 13 Jun 2014

Chad Greene on 6 Jun 2014
Edited: Chad Greene on 6 Jun 2014
Since you didn't give us your fids or window data, I'll make them up:
fids = rand(4,5,6,7,8,9);
window = 2*ones(1,5)-3;
Now your entire script you provided in your question can be replaced by this:
fids = bsxfun(@times,fids,window);
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John on 16 Jun 2014
Edited: John on 16 Jun 2014
Thanks for the good answer. I understand it now. Matlab's doc on @times is very primitive.
So, if the vector is to apply to the 4th dimension, your vector should be defined as:
window = 2*ones(1,1,1,7)-3;
Back to the vector in the original question. It has to be arranged as
window = reshape(window, [1,size(window)]);
fids = bsxfun(@times,fids,window);
and if the multiplication is to the 4th dimension, arrange it as:
window = reshape(window, [1,1,1,size(window)]);
Correct?