How I compute multiple sum in matlab for 4D matrix?
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How I compute multiple sum in matlab for 4D matrices as below? U and V are 4D matrices.
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Matt J
am 11 Sep. 2018
Bearbeitet: Matt J
am 11 Sep. 2018
Notice that the only indices shared between U and V are j and q. Therefore, you can minimize multiplication operations as follows,
partialU=sum(sum(U,4),1); %sum over i and r
partialV=sum(sum(V,4),1); %sum over k and s
A=sum(partialU(:).*partialV(:)); %sum over j and q
6 Kommentare
Matt J
am 11 Sep. 2018
Bearbeitet: Matt J
am 11 Sep. 2018
You should edit your original post with this new equation and information about q_r and q_s. The new expression is rather unclear. You have the symbol q being used for two different things, both as a symbolic variable and as an index of summation.
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