How to refer to multiple separate columns?

B =

    15    12     9     6     3
     2     4     6     8    10
     6    12    18    24    30

How do I refer to columns 1 and 3? I know that:

ans = B(:,1:3)

will give me columns 1 through 3, but how do I get just columns 1 and 3 without column 2 in the middle? Thanks!

Answer 1

[KSSV]

B(:,[1 3])

Or

B(:,1:2:3)

Or, USe logicals

idx = logical([1 0 1]) ;
B(:,idx)