scalbnf3
Scale by an integer power of radix
Part of scalbln(3).
Usage
double scalbln(double
x,
long
e);
float
scalblnf(float
x,
long
e);
long
double
scalblnl(long
double
x,
long
e);
double scalbn(double
x,
int
e);
float
scalbnf(float
x,
int
e);
long
double
scalbnl(long
double
x,
int
e);
_ISOC99_SOURCE { | | _POSIX_C_SOURCE
>=
200112L}
_ISOC99_SOURCE { | | _POSIX_C_SOURCE
>=
200112L}
Library
Math library (libm, -lm)
Overview
These functions multiply their first argument x by FLT_RADIX (probably 2) to the power of e, that is:
x * FLT_RADIX ** e
The definition of FLT_RADIX can be obtained by including <float.h>.
Return value
On success, these functions return x * FLT_RADIX ** e.
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 floating-point exception (
FE_OVERFLOW) is raised.
- Range error, underflow
-
errno is set to ERANGE. An underflow floating-point exception (
FE_UNDERFLOW) is raised.
Attributes
For an explanation of the terms used in this section, see attributes(7).
| Interface | Attribute | Value |
| scalbn(), scalbnf(), scalbnl(), scalbln(), scalblnf(), scalblnl() | Thread safety | MT-Safe |
Notes
If FLT_RADIX equals 2 (which is usual), then scalbn() is equivalent to ldexp(3).
History
- Arch Linux 2026-11-01: the text shown here
- Debian 13 (Trixie)
- Debian 12 (Bookworm)
- Debian 11 (Bullseye)
- Debian 10 (Buster)
- Debian 9 (Stretch)
- Debian 8 (Jessie)
- Debian 7 (Wheezy)
- Debian 6.0 (Squeeze)
- Debian 5.0 (Lenny)
- Debian 4.0 (Etch)
- Debian 3.1 (Sarge)