scalb(3) - BetterMan

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Options · 4

Domain error: x is 0, and exp is positive infinity, or x is positive infinity and exp is negative infinity and the other argument is not a NaN	errno is set to EDOM. An invalid floating-point exception (FE_INVALID) is raised.
Range error, overflow	errno is set to ERANGE. 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.
scalb()	4.3BSD. Obsolescent in POSIX.1-2001; Removed in POSIX.1-2008, recommending the use of scalbln(3), scalblnf(3), or scalblnl(3) instead.

NAME

scalb, scalbf, scalbl - multiply floating-point number by integral power of radix (OBSOLETE)

LIBRARY

Math library (libm, -lm)

SYNOPSIS

bash

#include <math.h>

bash

[[deprecated]] double scalb(double \nx\n, double \nexp\n);\n
\n[[deprecated]] float scalbf(float \nx\n, float \nexp\n);\n
\n[[deprecated]] long double scalbl(long double \nx\n, long double \nexp\n);

scalb():

bash


\n
    _XOPEN_SOURCE >= 500
\n
        || /* Since glibc 2.19: */ _DEFAULT_SOURCE
\n
        || /* glibc <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE

scalbf(), scalbl():

bash


\n
    _XOPEN_SOURCE >= 600
\n
        || /* Since glibc 2.19: */ _DEFAULT_SOURCE
\n
        || /* glibc <= 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:

bash


\n
    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 or exp is a NaN, a NaN is returned.

If x is positive infinity (negative infinity), and exp is not negative infinity, positive infinity (negative infinity) is returned.

If x is +0 (-0), and exp is not positive infinity, +0 (-0) is returned.

If x is zero, and exp is positive infinity, a domain error occurs, and a NaN is returned.

If x is an infinity, and exp is negative infinity, a domain error occurs, and a NaN 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:

Domain error: x is 0, and exp is positive infinity, or x is positive infinity and exp is negative infinity and the other argument is not a NaN: errno is set to EDOM. An invalid floating-point exception (FE_INVALID) is raised.
Range error, overflow: errno is set to ERANGE. 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
scalb (), scalbf (), scalbl ()	Thread safety	MT-Safe

STANDARDS

None.

HISTORY

scalb(): 4.3BSD. Obsolescent in POSIX.1-2001; Removed in POSIX.1-2008, recommending the use of scalbln(3), scalblnf(3), or scalblnl(3) instead.

BUGS

Before glibc 2.20, these functions did not set errno for domain and range errors.