1FREXP(3P)                  POSIX Programmer's Manual                 FREXP(3P)
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PROLOG

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

12       frexp, frexpf, frexpl - extract mantissa and  exponent  from  a  double
13       precision number
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SYNOPSIS

16       #include <math.h>
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18       double frexp(double num, int *exp);
19       float frexpf(float num, int *exp);
20       long double frexpl(long double num, int *exp);
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DESCRIPTION

24       These  functions shall break a floating-point number num into a normal‐
25       ized fraction and an integral power of 2. The integer exponent shall be
26       stored in the int object pointed to by exp.
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RETURN VALUE

29       For  finite  arguments,  these functions shall return the value x, such
30       that x has a magnitude in the interval [0.5,1) or 0, and num  equals  x
31       times 2 raised to the power *exp.
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33       If  num  is  NaN,  a  NaN  shall  be returned, and the value of *exp is
34       unspecified.
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36       If num is ±0, ±0 shall be returned, and the value of *exp shall be 0.
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38       If num is ±Inf, num shall be returned, and the value of *exp is unspec‐
39       ified.
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ERRORS

42       No errors are defined.
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44       The following sections are informative.
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EXAMPLES

47       None.
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APPLICATION USAGE

50       None.
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RATIONALE

53       None.
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FUTURE DIRECTIONS

56       None.
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SEE ALSO

59       isnan(),    ldexp(),   modf(),   the   Base   Definitions   volume   of
60       IEEE Std 1003.1-2001, <math.h>
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63       Portions of this text are reprinted and reproduced in  electronic  form
64       from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
65       -- Portable Operating System Interface (POSIX),  The  Open  Group  Base
66       Specifications  Issue  6,  Copyright  (C) 2001-2003 by the Institute of
67       Electrical and Electronics Engineers, Inc and The Open  Group.  In  the
68       event of any discrepancy between this version and the original IEEE and
69       The Open Group Standard, the original IEEE and The Open Group  Standard
70       is  the  referee document. The original Standard can be obtained online
71       at http://www.opengroup.org/unix/online.html .
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75IEEE/The Open Group                  2003                            FREXP(3P)
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