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 

       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 featuretestmacros(7)):

       scalbln(), scalblnf(), scalblnl():
              XOPENSOURCE >= 600 || ISOC99SOURCE ||
              POSIXCSOURCE >= 200112L;
              or cc -std=c99
       scalbn(), scalbnf(), scalbnl():
              BSDSOURCE || SVIDSOURCE || XOPENSOURCE >= 600 ||
              ISOC99SOURCE || POSIXCSOURCE >= 200112L;
              or cc -std=c99

DESCRIPTION
       These functions multiply their first argument x by FLTRADIX  (probably
       2) to the power of exp, that is:

           x * FLTRADIX ** exp

       The definition of FLTRADIX can be obtained by including .

RETURN VALUE
       On success, these functions return x * FLTRADIX ** 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
       HUGEVAL,  HUGEVALF,  or HUGEVALL, 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  matherror(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 (FEOVERFLOW) is raised.

       Range error, underflow
              An underflow floating-point exception (FEUNDERFLOW) 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() │               │         │
       └──────────────────────────────────┴───────────────┴─────────┘
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 FLTRADIX 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)