std::signbit

 

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Defined in header <cmath>
bool signbit( float arg );		(since C++11)
bool signbit( double arg );		(since C++11)
bool signbit( long double arg );		(since C++11)

Determines if the given floating point number arg is negative.

Parameters

arg

-

floating point value

Return value

true if arg is negative, false otherwise

See also

abs(float)fabsfabsffabsl (C++11)(C++11)	absolute value of a floating point value (\(\small{|x|}\)|x|) (function)
copysigncopysignfcopysignl (C++11)(C++11)(C++11)	copies the sign of a floating point value (function)