How can I unfold a tensor?

In the algorithm of High order SVD, A is a tensor, how to unfold it? for examplr,A(1),A(2),A(3). Thank you so much .

Answer 1

[Rachel]

function [X] = Unfold( T, dim, i )

X = reshape(shiftdim(T,i-1), dim(i), []);

Answer 2

[the cyclist]

I am not sure I understand, but I think you want to do

A(:)

or use the reshape() command.