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FREXP(3P)                  POSIX Programmer's Manual                 FREXP(3P)
PROLOG
       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
       frexp, frexpf, frexpl -- extract mantissa and exponent  from  a  double
       precision number
SYNOPSIS
       #include <math.h>
       double frexp(double num, int *exp);
       float frexpf(float num, int *exp);
       long double frexpl(long double num, int *exp);
DESCRIPTION
       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.1-2008
       defers to the ISO C standard.
       These functions shall break a floating-point number num into a  normal-
       ized fraction and an integral power of 2. The integer exponent shall be
       stored in the int object pointed to by exp.
RETURN VALUE
       For finite arguments, these functions shall return the  value  x,  such
       that  x  has a magnitude in the interval [1/2,1) or 0, and num equals x
       times 2 raised to the power *exp.
       If num is NaN, a NaN shall be  returned,  and  the  value  of  *exp  is
       unspecified.
       If num is +-0, +-0 shall be returned, and the value of *exp shall be 0.
       If  num  is  +-Inf,  num  shall  be  returned, and the value of *exp is
       unspecified.
ERRORS
       No errors are defined.
       The following sections are informative.
EXAMPLES
       None.
APPLICATION USAGE
       None.
RATIONALE
       None.
FUTURE DIRECTIONS
       None.
SEE ALSO
       isnan(), ldexp(), modf()
       The Base Definitions volume of POSIX.1-2008, <math.h>
COPYRIGHT
       Portions of this text are reprinted and reproduced in  electronic  form
       from IEEE Std 1003.1, 2013 Edition, Standard for Information Technology
       -- Portable Operating System Interface (POSIX),  The  Open  Group  Base
       Specifications Issue 7, Copyright (C) 2013 by the Institute of Electri-
       cal and Electronics Engineers,  Inc  and  The  Open  Group.   (This  is
       POSIX.1-2008  with  the  2013  Technical Corrigendum 1 applied.) 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.unix.org/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, see https://www.ker-
       nel.org/doc/man-pages/reporting_bugs.html .
IEEE/The Open Group                  2013                            FREXP(3P)