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<cat>Dev.Lua</cat> # NaN⤶ ⤶ If <page>nil</page> was supposed to be a number, it would be <page>NaN</page>. ⤶ This value is generated from heinous math operations such as the following:⤶ ⤶ ```lua⤶ local NaN = 0 / 0⤶ ```⤶ ⤶ This is not to be confused with infinity (which for some reason is confused with).⤶ ⤶ ```lua⤶ local Infinity = math.huge or 1 / 0⤶ ```<title>Concepts - Not a Number (NaN)</title>⤶ # Not a Number (NaN) ⤶ Not a Number (NaN) is a special value returned as the result of math operations that are logically or mathematically invalid. ⤶ One of the more common ways to create a NaN value is to divide zero by zero. ⤶ ⤶ ⤶ <example>⤶ <description>⤶ NaN has some qualities that may not be immediately obvious, but are important to know:⤶ </description>⤶ <code>⤶ -- Intentionally create a NaN value for testing⤶ local NaN = 0/0⤶ ⤶ -- It is not self-similar⤶ -- This is the main way that NaN values are detected in lua⤶ -- Prints: false⤶ print( "Is NaN self-similar?", NaN == NaN )⤶ ⤶ -- It isn't nil⤶ -- Prints: false⤶ print( "Is NaN nil?", NaN == nil )⤶ ⤶ -- It's not positive⤶ -- Prints: false⤶ print( "Is NaN positive?", NaN > 0 )⤶ ⤶ -- It's not negative⤶ -- Prints: false⤶ print( "Is NaN negative?", NaN < 0 )⤶ ⤶ -- It's not zero⤶ -- Prints: false⤶ print( "Is NaN zero?", NaN == 0 )⤶ ⤶ -- It's not true⤶ -- Prints: false⤶ print( "Is NaN true?", NaN == true )⤶ ⤶ -- It's not false⤶ -- Prints: false⤶ print( "Is NaN false?", NaN == false )⤶ ⤶ -- It's truthy⤶ -- Prints: NaN is truthy⤶ if NaN then⤶ print( "Is NaN truthy?", true )⤶ end⤶ ⤶ -- Despite the name, it is a number⤶ -- Prints: true⤶ print( "Is NaN a number?", type( NaN ) == "number" )⤶ </code>⤶ </example>⤶ ⤶ ## Additional Info⤶ ⤶ The NaN value originates from the [Floating-Point Number (float)](https://en.wikipedia.org/wiki/Single-precision_floating-point_format) standard used almost universally by software and hardware for non-integer numbers.⤶ ⤶ ⤶

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