std::signbit

 

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fpclassify (C++11) isfinite (C++11) isinf (C++11) isnan (C++11) isnormal (C++11) signbit (C++11)	isgreater (C++11) isgreaterequal (C++11) isless (C++11) islessequal (C++11) islessgreater (C++11) isunordered (C++11)
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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) fabs	absolute value of a floating point value (|x|) (function)
copysign (C++11)	copies the sign of a floating point value (function)