test.m

x_val = [1 2 3 4 5 6 7 8 9 10];
n = length(x_val);
x_ = linspace(0, 11, 100);
F_val = zeros(1, length(x));
for j = 1:length(x_)
    if x_(j) <= x(1)
        F_val(j) = 0;
        continue;
    end
    if x_(j) > x_val(n)
        F_val(j) = 1;
        continue;
    end
    for i = 1:n-1
        if x_val(i) < x_(j) && x_(j) <= x_val(i+1)
            F_val(j) = i / n;
        end
    end
end