What does E mean? And what are its dimensions? If it's a 1x2 array that means a row and column, then you'd have to do A(E(1), E(2)).
If you simply did A(E) it would take that to mean you want two elements, A(E(1)) and A(E(2)), using E as linear indexes , not rows and columns. Since linear indexes go down the first column, then down the second column, etc. across all the columns, then A(E) would get A(1,1) and A(2,1). Just try it and see:
A=magic(4)
E = [1,2]
A(E)
