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Because this unordered property is often unexpected, direct comparisons with NaN must not be performed. Problems can arise when programmers write code that compares floating-point values without considering the semantics of NaN. For example, input validation checks that fail to consider the possibility of a NaN value as input can produce unexpected results. See rule NUM08-J. Check floating-point inputs for exceptional values for additional information.
Noncompliant Code Example
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<ac:structured-macro ac:name="unmigrated-wiki-markup" ac:schema-version="1" ac:macro-id="88f870340083f7d1-a25011f2-4732499c-bfefb185-b4fc81290579a0796f865a49"><ac:plain-text-body><![CDATA[ | [[JLS 2005 | AA. Bibliography#JLS 05]] | [§4.2.3, Floating-Point Types, Formats, and Values | http://java.sun.com/docs/books/jls/third_edition/html/typesValues.html#4.2.3] | ]]></ac:plain-text-body></ac:structured-macro> |
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