std::signbit

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

Determines if the given floating point number arg is negative.

Parameters

arg

-

floating point value

Return value

nonzero value if arg is negative, ​0​ 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)