title: getting very small number instead of zero
body: <p>I'm doing some calculations and I ended up with this problem which is not getting zero. In my equation, the theoretical part suggests the result to be zero however Matlab throws very small non sensible number <code>z = -4.4409e-16</code>. <code>z</code> here should be zero. In <a href="http://www.mathworks.com/matlabcentral/answers/69-why-does-1-2-3-1-3-not-equal-zero" rel="nofollow">here</a>, the problem has been discussed why this occurs. I've tried to pass this value to <code>cos()</code> to get one as a result and indeed I got one. My question is now does Matlab treat this value as a zero or it is treated as is? Another question is to which level should I assume this value to be zero so that I can reassign this value to be zero?</p>