Fast way to replicate array

I have a matrix W of size ExF, and I have a matrix D of size NxFxNxE where D(n,:,n,:) = W'

Is there a fast way to replicate W to form D without having to loop through N

Thanks!

Answer 1

[Mohammad Abouali]

w=[1 2; ...
   3 4; ...
   5 6];
N=5;
E=size(w,1);
F=size(w,2);

D=repmat(reshape(w',1,F,1,E),N,1,N,1);

Answer 2

[Jan]

You want to obtain W from D?

W = squeeze(D(k, :, k, :)).'

[Thang Bui]

Nope, obtain D from W, the loop version looks roughly like this

D = zeros(N,F,N,E);
for n = 1:N
    D(n,:,n,:) = W'; % perhaps need permute here
end

Answer 3

[Andrei Bobrov]

i1 = bsxfun(@plus,[0;N]+1,(0:N-1)*(2*N+1));
i2 = bsxfun(@plus,i1,reshape((0:F)*i1(end),1,1,[]));
D = zeros(N,F,N,E);
D(i2) = permute(repmat(W,[1,1,N]),[2,3,1]);