matlab matrix get values in different columns

Question

Let my matrix be:

        A = 
        [1,2,3;
        4,5,6;
        7,8,9];

I have to extract the values in (1,2), (2,3), (3,1). I tried the following:

        c = [2,3,1]';

        A(:, c)

but it gives a 3x3 matrix instead of 3x1.

How can I do it efficiently in matlab?

Looks like a duplicate case, if only the SO search system was better! — Divakar, Jan 29 '15 at 16:40
@Divakar Mark it as duplicate if you find it. It really looks like that this has been answered before in SO. — Ander Biguri, Jan 29 '15 at 16:42

score 2 · Accepted Answer · answered Jan 29 '15 at 16:42

2

The best way to extract arbitrary values from a matrix is to use linear indices.

You can use sub2ind

ind=sub2ind(size(A),[1 2 3], [2 3 1]);
val=A(ind);

answered Jan 29 '15 at 16:42

Ander Biguri

1 Answers1