Indexing and turning into column vector

Is there a quick way to index into an array and then make it a column vector without reshaping? See below for example:

a = ones(5, 4, 3, 2)

%Works

aR = reshape(a(:, :, :, 2), 1, [])

%Any alternatives?

%a(:, :, :, 2)(:), etc

Thanks in advance

Answer 1

[James Tursa]

Not really. It's going to be a two-step process no matter how you do it (without resorting to a mex routine, which isn't worth it IMO). The indexing you do above is a deep data copy, but the reshape is very quick and is not a deep copy, so I wouldn't worry about it. Just do what you are currently doing. Note that if you want a column vector output you should be doing reshape(a(:, :, :, 2), [], 1).