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SCALBLN(3)                 Linux Programmer's Manual                SCALBLN(3)

NAME
       scalbn, scalbnf, scalbnl, scalbln, scalblnf, scalblnl - multiply float-
       ing-point number by integral power of radix
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);
       Link with -lm.
   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
       scalbln(), scalblnf(), scalblnl():
              _XOPEN_SOURCE >= 600 || _ISOC99_SOURCE ||
              _POSIX_C_SOURCE >= 200112L;
              or cc -std=c99
       scalbn(), scalbnf(), scalbnl():
              _BSD_SOURCE || _SVID_SOURCE || _XOPEN_SOURCE >= 600 ||
              _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L;
              or cc -std=c99
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 is a NaN, a NaN is returned.
       If x is positive infinity (negative infinity), positive infinity (nega-
       tive 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
   Multithreading (see pthreads(7))
       The scalbn(), scalbnf(), scalbnl(), scalbln(),  scalblnf(),  and  scal-
       blnl() functions are thread-safe.
CONFORMING TO
       C99, POSIX.1-2001.
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).
SEE ALSO
       ldexp(3), scalb(3)
COLOPHON
       This  page  is  part of release 3.53 of the Linux man-pages project.  A
       description of the project, and information about reporting  bugs,  can
       be found at http://www.kernel.org/doc/man-pages/.

                                  2013-06-21                        SCALBLN(3)