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frexp(3p) — Linux manual page

FREXP(3P)               POSIX Programmer's ManualFREXP(3P)

PROLOG        top

       This manual page is part of the POSIX Programmer's Manual.  The       Linux implementation of this interface may differ (consult the       corresponding Linux manual page for details of Linux behavior), or       the interface may not be implemented on Linux.

NAME        top

       frexp, frexpf, frexpl — extract mantissa and exponent from a       double precision number

SYNOPSIS        top

       #include <math.h>       double frexp(doublenum, int *exp);       float frexpf(floatnum, int *exp);       long double frexpl(long doublenum, int *exp);

DESCRIPTION        top

       The functionality described on this reference page is aligned with       the ISO C standard. Any conflict between the requirements       described here and the ISO C standard is unintentional. This       volume of POSIX.1‐2017 defers to the ISO C standard.       These functions shall break a floating-point numbernum into a       normalized fraction and an integral power of 2. The integer       exponent shall be stored in theintobject pointed to byexp.

RETURN VALUE        top

       For finite arguments, these functions shall return the valuex,       such thatx has a magnitude in the interval [½,1) or 0, andnum       equalsx times 2 raised to the power *exp.       Ifnum is NaN, a NaN shall be returned, and the value of *exp is       unspecified.       Ifnum is ±0, ±0 shall be returned, and the value of *exp shall be       0.       Ifnum is ±Inf,num shall be returned, and the value of *exp is       unspecified.

ERRORS        top

       No errors are defined.The following sections are informative.

EXAMPLES        top

       None.

APPLICATION USAGE        top

       None.

RATIONALE        top

       None.

FUTURE DIRECTIONS        top

       None.

SEE ALSO        top

isnan(3p),ldexp(3p),modf(3p)       The Base Definitions volume of POSIX.1‐2017,math.h(0p)

COPYRIGHT        top

       Portions of this text are reprinted and reproduced in electronic       form from IEEE Std 1003.1-2017, Standard for Information       Technology -- Portable Operating System Interface (POSIX), The       Open Group Base Specifications Issue 7, 2018 Edition, Copyright       (C) 2018 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 athttp://www.opengroup.org/unix/online.html .       Any typographical or formatting errors that appear in this page       are most likely to have been introduced during the conversion of       the source files to man page format. To report such errors, seehttps://www.kernel.org/doc/man-pages/reporting_bugs.html .IEEE/The Open Group                2017FREXP(3P)

Pages that refer to this page:math.h(0p), ldexp(3p), modf(3p)

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