Poster of Linux kernelThe best gift for a Linux geek
FREXP

FREXP

Section: POSIX Programmer's Manual (P) Updated: 2003
Local index Up
 

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

These functions shall break a floating-point number num into a normalized 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 [0.5,1) 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 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 .


 

Index

NAME
SYNOPSIS
DESCRIPTION
RETURN VALUE
ERRORS
EXAMPLES
APPLICATION USAGE
RATIONALE
FUTURE DIRECTIONS
SEE ALSO
COPYRIGHT

This document was created by man2html, using the manual pages.
Time: 21:46:21 GMT, April 16, 2011