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NAME

```       scalbn,  scalbnf, scalbnl, scalbln, scalblnf, scalblnl - multiply floating-point number by

```

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>.

```

RETURNVALUE

```       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 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 attributes(7).

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

CONFORMINGTO

```       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).

```

SEEALSO

```       ldexp(3), scalb(3)

```

COLOPHON

```       This  page  is  part of release 4.15 of the Linux man-pages project.  A description of the