... them:Ex|n+1 /2 i,j+1 /2, k+1 /2 −Ex|n−1 /2 i,j+1 /2, k+1 /2 ∆t=1i,j+1 /2, k−1/ 2 ·Hz|ni,j+1,k+1 /2 −Hz|ni,j,k+1 /2 ∆y−Hy|ni,j+1 /2, k+1−Hy|ni,j+1 /2, k∆z−Jsourcex|i,j+1 /2, k+1/ 2 −σi,j+1 /2, k+1/ ... them:Ex|n+1 /2 i,j+1 /2, k+1 /2 −Ex|n−1 /2 i,j+1 /2, k+1 /2 ∆t=1i,j+1 /2, k−1/ 2 ·Hz|ni,j+1,k+1 /2 −Hz|ni,j,k+1 /2 ∆y−Hy|ni,j+1 /2, k+1−Hy|ni,j+1 /2, k∆z−Jsourcex|i,j+1 /2, k+1/ 2 −σi,j+1 /2, k+1/ ... [N−1∑k=0N−1∑i=0ak[n]expj (2 . fit +2 . i.k/N)+3N /2 1∑k=NN−1∑∀i=oddak[n]expj (2 . fit +2 . i.k/N+i∆φ1)+2N−1∑k=3N /2 N−1∑∀i=oddak[n]expj (2 . fit +2 .(i+1).k/N+i∆φ 2 )+5N /2 1∑k=2NN−1∑∀i=evenak[n]expj (2 ....