# scalblnl

```SCALBLN(3)                 Linux Programmer's Manual                SCALBLN(3)

NAME
scalbn, scalbnf, scalbnl, scalbln, scalblnf, scalblnl - multiply float-
ing-point 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);

Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

scalbln(), scalblnf(), scalblnl():
_ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L
|| /* Since glibc 2.19: */ _DEFAULT_SOURCE
scalbn(), scalbnf(), scalbnl():
_ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L
|| /* Since glibc 2.19: */ _DEFAULT_SOURCE
|| /* Glibc versions <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE

DESCRIPTION
These functions multiply their first argument x by FLT_RADIX  (probably
2) to the power of exp, that is:

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 (nega-
tive 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  re-
turn 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 floating-point exception (FE_OVERFLOW) is raised.

Range error, underflow
An underflow floating-point exception (FE_UNDERFLOW) is raised.

These functions do not set errno.

VERSIONS
These functions first appeared in glibc in version 2.1.

ATTRIBUTES
For an  explanation  of  the  terms  used  in  this  section,  see  at-
tributes(7).

+----------------------------------+---------------+---------+
|Interface                         | Attribute     | Value   |
+----------------------------------+---------------+---------+
|scalbn(), scalbnf(), scalbnl(),   | Thread safety | MT-Safe |
|scalbln(), scalblnf(), scalblnl() |               |         |
+----------------------------------+---------------+---------+
CONFORMING TO
C99, POSIX.1-2001, POSIX.1-2008.

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).