SCALBLN
Section: Linux Programmer's Manual (3)
Updated: 20130621
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NAME
scalbn, scalbnf, scalbnl, scalbln, scalblnf, scalblnl 
multiply floatingpoint number by integral power of radix
SYNOPSIS
#include <math.h>
double scalbln(double x, long int exp);
float scalblnf(float x, long int exp);
long double scalblnl(long double x, long int exp);
double scalbn(double x, int exp);
float scalbnf(float x, int exp);
long double scalbnl(long double x, int exp);
Link with lm.
Feature Test Macro Requirements for glibc (see
feature_test_macros(7)):
scalbln(),
scalblnf(),
scalblnl():

_XOPEN_SOURCE >= 600  _ISOC99_SOURCE 
_POSIX_C_SOURCE >= 200112L;
or
cc std=c99
scalbn(),
scalbnf(),
scalbnl():

_BSD_SOURCE  _SVID_SOURCE  _XOPEN_SOURCE >= 600  _ISOC99_SOURCE 
_POSIX_C_SOURCE >= 200112L;
or
cc std=c99
DESCRIPTION
These functions multiply their first argument
x
by
FLT_RADIX
(probably 2)
to the power of
exp,
that is:
x * FLT_RADIX ** exp
The definition of
FLT_RADIX
can be obtained by including
<float.h>.
RETURN VALUE
On success, these functions return
x
*
FLT_RADIX
**
exp.
If
x
is a NaN, a NaN is returned.
If
x
is positive infinity (negative infinity),
positive infinity (negative infinity) is returned.
If
x
is +0 (0), +0 (0) is returned.
If the result overflows,
a range error occurs,
and the functions return
HUGE_VAL,
HUGE_VALF,
or
HUGE_VALL,
respectively, with a sign the same as
x.
If the result underflows,
a range error occurs,
and the functions return zero, with a sign the same as
x.
ERRORS
See
math_error(7)
for information on how to determine whether an error has occurred
when calling these functions.
The following errors can occur:
 Range error, overflow

An overflow floatingpoint exception
(FE_OVERFLOW)
is raised.
 Range error, underflow

An underflow floatingpoint exception
(FE_UNDERFLOW)
is raised.
These functions do not set
errno.
VERSIONS
These functions first appeared in glibc in version 2.1.
ATTRIBUTES
Multithreading (see pthreads(7))
The
scalbn(),
scalbnf(),
scalbnl(),
scalbln(),
scalblnf(),
and
scalblnl()
functions are threadsafe.
CONFORMING TO
C99, POSIX.12001.
NOTES
These functions differ from the obsolete functions described in
scalb(3)
in the type of their second argument.
The functions described on this page have a second argument
of an integral type, while those in
scalb(3)
have a second argument of type
double.
If
FLT_RADIX
equals 2 (which is usual), then
scalbn()
is equivalent to
ldexp(3).
SEE ALSO
ldexp(3),
scalb(3)
COLOPHON
This page is part of release 3.74 of the Linux
manpages
project.
A description of the project,
information about reporting bugs,
and the latest version of this page,
can be found at
http://www.kernel.org/doc/manpages/.
Index
 NAME

 SYNOPSIS

 DESCRIPTION

 RETURN VALUE

 ERRORS

 VERSIONS

 ATTRIBUTES

 Multithreading (see pthreads(7))

 CONFORMING TO

 NOTES

 SEE ALSO

 COLOPHON
