If the difference between the first element and the last element is not a multpiple of 1 you cannot have the interval between numbers be 1 for all. However, if your goal is to ensure that the last element is some particular number and are willing to compromise (it seems you do with 1.6 and 2.4), how about constructing v
like this?
v1 = -2.4; v_last = 2.4;
v = v1 : v_last;
if v(end) ~= v_last
v = [v, v_last];
end