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SCALB(3)                   Linux Programmer's Manual                  SCALB(3)
NAME
       scalb,  scalbf,  scalbl  -  multiply  floating-point number by integral
       power of radix (OBSOLETE)
SYNOPSIS
       #include <math.h>
       double scalb(double x, double exp);
       float scalbf(float x, float exp);
       long double scalbl(long double x, long double exp);
       Link with -lm.
   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
       scalb():
           _XOPEN_SOURCE >= 500
               || /* Since glibc 2.19: */ _DEFAULT_SOURCE
               || /* Glibc versions <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE
       scalbf(), scalbl():
           _XOPEN_SOURCE >= 600
               || /* 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:
           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
              An invalid floating-point exception (FE_INVALID) is raised.
       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.
ATTRIBUTES
       For  an  explanation  of  the  terms  used   in   this   section,   see
       attributes(7).
       +-----------------------------+---------------+---------+
       |Interface                    | Attribute     | Value   |
       +-----------------------------+---------------+---------+
       |scalb(), scalbf(), scalbl()  | Thread safety | MT-Safe |
       +-----------------------------+---------------+---------+
CONFORMING TO
       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() func-
       tion is from 4.3BSD.
       scalbf() and scalbl()  are  unstandardized;  scalbf()  is  nevertheless
       present on several other systems
SEE ALSO
       ldexp(3), scalbln(3)
COLOPHON
       This  page  is  part of release 4.15 of the Linux man-pages project.  A
       description of the project, information about reporting bugs,  and  the
       latest     version     of     this    page,    can    be    found    at
       https://www.kernel.org/doc/man-pages/.
                                  2017-09-15                          SCALB(3)