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

NAME         top

scalbn,  scalbnf,  scalbnl,  scalbln,  scalblnf,  scalblnl - multiply
floating-point number by integral power of radix

SYNOPSIS         top

#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         top

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         top

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         top

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         top

These functions first appeared in glibc in version 2.1.

ATTRIBUTES         top

For an explanation of the terms used in this section, see
attributes(7).

┌──────────────────────────────────┬───────────────┬─────────┐
│Interface                         Attribute     Value   │
├──────────────────────────────────┼───────────────┼─────────┤
│scalbn(), scalbnf(), scalbnl(),   │ Thread safety │ MT-Safe │
│scalbln(), scalblnf(), scalblnl() │               │         │
└──────────────────────────────────┴───────────────┴─────────┘

CONFORMING TO         top

C99, POSIX.1-2001, POSIX.1-2008.