NAME

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

LIBRARY

       Math library (libm, -lm)

SYNOPSIS

       #include <math.h>

       [[deprecated]] double scalb(double x, double exp);
       [[deprecated]] float scalbf(float x, float exp);
       [[deprecated]] long double scalbl(long double x, long double exp);

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

       scalb():
           _XOPEN_SOURCE >= 500
               || /* Since glibc 2.19: */ _DEFAULT_SOURCE
               || /* glibc <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE

       scalbf(), scalbl():
           _XOPEN_SOURCE >= 600
               || /* Since glibc 2.19: */ _DEFAULT_SOURCE
               || /* 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:

           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

       scalb()  is  specified  in POSIX.1-2001, but marked obsolescent.  POSIX.1-2008 removes the
       specification of scalb(), recommending the use of scalbln(3), scalblnf(3), or  scalblnl(3)
       instead.  The scalb() function is from 4.3BSD.

       scalbf()  and  scalbl()  are  unstandardized;  scalbf() is nevertheless present on several
       other systems

BUGS

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

SEE ALSO

       ldexp(3), scalbln(3)