simple question

[Vitaliy A Repin]

Hello!

One simple question. 
There is a matrix A:
1 2
3 4
5 6
7 8
9 10 
0 2
3 4
..

How can I use the first/second column or row of this matrix?
Is there any Octave operator which gives me the n-th column(row)
of matrix as vector?

Thanks.

Good-bye!
                                                               WBR, Vitaly.