how do u make a new value that is the sum of two columns

So I have a value r which is a variable with two columns of value represent the returns of two stocks.

now I wanna make a new variable that is 0.6 of first stock and 0.4 of second stock

how should I do that

Answer 1

[Paul Hoffrichter]

A = [1 2 ;3 4; 5 6 ;7 8; 9 10; 11 12; 13 14; 15 16]
A =
     1     2
     3     4
     5     6
     7     8
     9    10
    11    12
    13    14
    15    16
K>> w = .6*A(:,1) + .4*A(:,2);
w =
    1.4000
    3.4000
    5.4000
    7.4000
    9.4000
   11.4000
   13.4000
   15.4000

Answer 2

[Jan]

A = [1 2 ;3 4; 5 6 ;7 8; 9 10; 11 12; 13 14; 15 16];
B = A * [0.6; 0.4]