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<H1>SCALBLN</H1>
Section: Linux Programmer's Manual (3)<BR>Updated: 2017-09-15<BR><A HREF="#index">Index</A>
<A HREF="/cgi-bin/man/man2html">Return to Main Contents</A><HR>
<A NAME="lbAB">&nbsp;</A>
<H2>NAME</H2>
scalbn, scalbnf, scalbnl, scalbln, scalblnf, scalblnl -
multiply floating-point number by integral power of radix
<A NAME="lbAC">&nbsp;</A>
<H2>SYNOPSIS</H2>
<B>#include &lt;<A HREF="file:///usr/include/math.h">math.h</A>&gt;</B>
<P>
<B>double scalbln(double </B><I>x</I><B>, long int </B><I>exp</I><B>);</B>
<BR>
<B>float scalblnf(float </B><I>x</I><B>, long int </B><I>exp</I><B>);</B>
<BR>
<B>long double scalblnl(long double </B><I>x</I><B>, long int </B><I>exp</I><B>);</B>
<P>
<B>double scalbn(double </B><I>x</I><B>, int </B><I>exp</I><B>);</B>
<BR>
<B>float scalbnf(float </B><I>x</I><B>, int </B><I>exp</I><B>);</B>
<BR>
<B>long double scalbnl(long double </B><I>x</I><B>, int </B><I>exp</I><B>);</B>
<P>
Link with <I>-lm</I>.
<P>
Feature Test Macro Requirements for glibc (see
<B><A HREF="/cgi-bin/man/man2html?7+feature_test_macros">feature_test_macros</A></B>(7)):
<P>
<B>scalbln</B>(),
<B>scalblnf</B>(),
<B>scalblnl</B>():
<DL COMPACT><DT id="1"><DD>
_ISOC99_SOURCE || _POSIX_C_SOURCE&nbsp;&gt;=&nbsp;200112L
<BR>&nbsp;&nbsp;&nbsp;&nbsp;||&nbsp;/*&nbsp;Since&nbsp;glibc&nbsp;2.19:&nbsp;*/&nbsp;_DEFAULT_SOURCE
</DL>
<BR>
<B>scalbn</B>(),
<B>scalbnf</B>(),
<B>scalbnl</B>():
<DL COMPACT><DT id="2"><DD>
_ISOC99_SOURCE || _POSIX_C_SOURCE&nbsp;&gt;=&nbsp;200112L
<BR>&nbsp;&nbsp;&nbsp;&nbsp;||&nbsp;/*&nbsp;Since&nbsp;glibc&nbsp;2.19:&nbsp;*/&nbsp;_DEFAULT_SOURCE
<BR>&nbsp;&nbsp;&nbsp;&nbsp;||&nbsp;/*&nbsp;Glibc&nbsp;versions&nbsp;&lt;=&nbsp;2.19:&nbsp;*/&nbsp;_BSD_SOURCE&nbsp;||&nbsp;_SVID_SOURCE
</DL>
<A NAME="lbAD">&nbsp;</A>
<H2>DESCRIPTION</H2>
These functions multiply their first argument
<I>x</I>
by
<B>FLT_RADIX</B>
(probably 2)
to the power of
<I>exp</I>,
that is:
<P>
<PRE>
x * FLT_RADIX ** exp
</PRE>
<P>
The definition of
<B>FLT_RADIX</B>
can be obtained by including
<I>&lt;<A HREF="file:///usr/include/float.h">float.h</A>&gt;</I>.
<A NAME="lbAE">&nbsp;</A>
<H2>RETURN VALUE</H2>
On success, these functions return
<I>x</I>
*
<B>FLT_RADIX</B>
**
<I>exp</I>.
<P>
If
<I>x</I>
is a NaN, a NaN is returned.
<P>
If
<I>x</I>
is positive infinity (negative infinity),
positive infinity (negative infinity) is returned.
<P>
If
<I>x</I>
is +0 (-0), +0 (-0) is returned.
<P>
If the result overflows,
a range error occurs,
and the functions return
<B>HUGE_VAL</B>,
<B>HUGE_VALF</B>,
or
<B>HUGE_VALL</B>,
respectively, with a sign the same as
<I>x</I>.
<P>
If the result underflows,
a range error occurs,
and the functions return zero, with a sign the same as
<I>x</I>.
<A NAME="lbAF">&nbsp;</A>
<H2>ERRORS</H2>
See
<B><A HREF="/cgi-bin/man/man2html?7+math_error">math_error</A></B>(7)
for information on how to determine whether an error has occurred
when calling these functions.
<P>
The following errors can occur:
<DL COMPACT>
<DT id="3">Range error, overflow<DD>
An overflow floating-point exception
(<B>FE_OVERFLOW</B>)
is raised.
<DT id="4">Range error, underflow<DD>
An underflow floating-point exception
(<B>FE_UNDERFLOW</B>)
is raised.
</DL>
<P>
These functions do not set
<I>errno</I>.
<A NAME="lbAG">&nbsp;</A>
<H2>VERSIONS</H2>
These functions first appeared in glibc in version 2.1.
<A NAME="lbAH">&nbsp;</A>
<H2>ATTRIBUTES</H2>
For an explanation of the terms used in this section, see
<B><A HREF="/cgi-bin/man/man2html?7+attributes">attributes</A></B>(7).
<TABLE BORDER>
<TR VALIGN=top><TD><B>Interface</B></TD><TD><B>Attribute</B></TD><TD><B>Value</B><BR></TD></TR>
<TR VALIGN=top><TD>
<B>scalbn</B>(),
<B>scalbnf</B>(),
<B>scalbnl</B>(),
<BR>
<B>scalbln</B>(),
<B>scalblnf</B>(),
<B>scalblnl</B>()
</TD><TD>Thread safety</TD><TD>MT-Safe<BR></TD></TR>
</TABLE>
<A NAME="lbAI">&nbsp;</A>
<H2>CONFORMING TO</H2>
C99, POSIX.1-2001, POSIX.1-2008.
<A NAME="lbAJ">&nbsp;</A>
<H2>NOTES</H2>
These functions differ from the obsolete functions described in
<B><A HREF="/cgi-bin/man/man2html?3+scalb">scalb</A></B>(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
<B><A HREF="/cgi-bin/man/man2html?3+scalb">scalb</A></B>(3)
have a second argument of type
<I>double</I>.
<P>
If
<B>FLT_RADIX</B>
equals 2 (which is usual), then
<B>scalbn</B>()
is equivalent to
<B><A HREF="/cgi-bin/man/man2html?3+ldexp">ldexp</A></B>(3).
<A NAME="lbAK">&nbsp;</A>
<H2>SEE ALSO</H2>
<B><A HREF="/cgi-bin/man/man2html?3+ldexp">ldexp</A></B>(3),
<B><A HREF="/cgi-bin/man/man2html?3+scalb">scalb</A></B>(3)
<A NAME="lbAL">&nbsp;</A>
<H2>COLOPHON</H2>
This page is part of release 5.05 of the Linux
<I>man-pages</I>
project.
A description of the project,
information about reporting bugs,
and the latest version of this page,
can be found at
<A HREF="https://www.kernel.org/doc/man-pages/.">https://www.kernel.org/doc/man-pages/.</A>
<P>
<HR>
<A NAME="index">&nbsp;</A><H2>Index</H2>
<DL>
<DT id="5"><A HREF="#lbAB">NAME</A><DD>
<DT id="6"><A HREF="#lbAC">SYNOPSIS</A><DD>
<DT id="7"><A HREF="#lbAD">DESCRIPTION</A><DD>
<DT id="8"><A HREF="#lbAE">RETURN VALUE</A><DD>
<DT id="9"><A HREF="#lbAF">ERRORS</A><DD>
<DT id="10"><A HREF="#lbAG">VERSIONS</A><DD>
<DT id="11"><A HREF="#lbAH">ATTRIBUTES</A><DD>
<DT id="12"><A HREF="#lbAI">CONFORMING TO</A><DD>
<DT id="13"><A HREF="#lbAJ">NOTES</A><DD>
<DT id="14"><A HREF="#lbAK">SEE ALSO</A><DD>
<DT id="15"><A HREF="#lbAL">COLOPHON</A><DD>
</DL>
<HR>
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Time: 00:05:54 GMT, March 31, 2021
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