matrices - one array/column from a matrix

[slovac]

I have a matrix whose size is 3x3 and whose label is A_i,j
1 2 3
4 5 6
7 8 9

I would like to ask you how to reffer just to one of either arrays or columns. For example:
1 2 3

and
3
6
9

Can I use the following labels?:
A_1,j and A_i,3

Thank you

 

[HallsofIvy]

Yes, though, since that is not terribly common, it would be a good idea to state, on your paper, that you are using that notation.

 

[slovac]

Thank you