2 This code checks to see if a floating point value is equal to the special
3 Not A Number value (e.g., <code>if (x == Double.NaN)</code>). However,
4 because of the special semantics of <code>NaN</code>, no value
5 is equal to <code>Nan</code>, including <code>NaN</code>. Thus,
6 <code>x == Double.NaN</code> always evaluates to false.
8 To check to see if a value contained in <code>x</code>
9 is the special Not A Number value, use
10 <code>Double.isNaN(x)</code> (or <code>Float.isNaN(x)</code> if
11 <code>x</code> is floating point precision).