That's a lot of lines to do a simple thing. Also, your comments state that you want to identify values less than 4 but your code is identifying values greater than 4.
Consider these two lines
x = [1 2 3 4 5]; %row vector
isLowerThan = (x + [1;2;3]) < 4;
The produce a logica matrix "isLowerThan" where each column corresponds to one value in "x" compared added to [1;2;3]. The '1's (true's) show where the results are less than 4.
