matrix - Matlab: subtract vectors in a 3D array by a list of vectors -

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i have n groups, each group has m vectors of dimension d. these represented d*m*n matrix a.

i have n vectors of dimension d, represented d*n matrix b.

now subtract m vectors in group corresponding vector in b (and = 1,...,n).

this can done like: 

c = zeros(size(a));  = 1:n     j = 1:m         c(:,j,i) = a(:,j,i) - b(:,i);     end end

however, quite slow because of loop. please suggest me fast way that?

thank in advance help.

perfect case bsxfun -

c = bsxfun(@minus,a,permute(b,[1 3 2]))

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