signbit: zkušební značka

Originální popis anglicky: signbit - test sign

Návod, kniha: POSIX Programmer's Manual

STRUČNĚ

#include <math.h> int signbit(real-floating x);

POPIS / INSTRUKCE

The signbit() macro shall determine whether the sign of its argument value is negative. NaNs, zeros, and infinities have a sign bit.

NÁVRATOVÁ HODNOTA

The signbit() macro shall return a non-zero value if and only if the sign of its argument value is negative.

CHYBY / ERRORY

No errors are defined. The following sections are informative.

PŘÍKLADY POUŽITÍ

None.

APPLICATION USAGE

None.

RATIONALE

None.

FUTURE DIRECTIONS

None.

SOUVISEJÍCÍ

fpclassify() , isfinite() , isinf() , isnan() , isnormal() , the Base Definitions volume of IEEE Std 1003.1-2001, <math.h>

COPYRIGHT

Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of Electrical and Electronics Engineers, Inc and The Open Group. In the event of any discrepancy between this version and the original IEEE and The Open Group Standard, the original IEEE and The Open Group Standard is the referee document. The original Standard can be obtained online at http://www.opengroup.org/unix/online.html .