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Diffstat (limited to 'man/man3/scalbln.3')
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diff --git a/man/man3/scalbln.3 b/man/man3/scalbln.3 new file mode 100644 index 000000000..bedf5dbf8 --- /dev/null +++ b/man/man3/scalbln.3 @@ -0,0 +1,174 @@ +'\" t +.\" Copyright 2004 Andries Brouwer <aeb@cwi.nl>. +.\" and Copyright 2008, Linux Foundation, written by Michael Kerrisk +.\" <mtk.manpages@gmail.com> +.\" +.\" SPDX-License-Identifier: Linux-man-pages-copyleft +.\" +.TH scalbln 3 (date) "Linux man-pages (unreleased)" +.SH NAME +scalbn, scalbnf, scalbnl, scalbln, scalblnf, scalblnl \- +multiply floating-point number by integral power of radix +.SH LIBRARY +Math library +.RI ( libm ", " \-lm ) +.SH SYNOPSIS +.nf +.B #include <math.h> +.P +.BI "double scalbln(double " x ", long " exp ); +.BI "float scalblnf(float " x ", long " exp ); +.BI "long double scalblnl(long double " x ", long " exp ); +.P +.BI "double scalbn(double " x ", int " exp ); +.BI "float scalbnf(float " x ", int " exp ); +.BI "long double scalbnl(long double " x ", int " exp ); +.fi +.P +.RS -4 +Feature Test Macro Requirements for glibc (see +.BR feature_test_macros (7)): +.RE +.P +.BR scalbln (), +.BR scalblnf (), +.BR scalblnl (): +.nf + _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L + || /* Since glibc 2.19: */ _DEFAULT_SOURCE +.fi +.P +.BR scalbn (), +.BR scalbnf (), +.BR scalbnl (): +.nf + _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L + || /* Since glibc 2.19: */ _DEFAULT_SOURCE + || /* glibc <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE +.fi +.SH DESCRIPTION +These functions multiply their first argument +.I x +by +.B FLT_RADIX +(probably 2) +to the power of +.IR exp , +that is: +.P +.nf + x * FLT_RADIX ** exp +.fi +.P +The definition of +.B FLT_RADIX +can be obtained by including +.IR <float.h> . +.\" not in /usr/include but in a gcc lib +.SH RETURN VALUE +On success, these functions return +.I x +* +.B FLT_RADIX +** +.IR exp . +.P +If +.I x +is a NaN, a NaN is returned. +.P +If +.I x +is positive infinity (negative infinity), +positive infinity (negative infinity) is returned. +.P +If +.I x +is +0 (\-0), +0 (\-0) is returned. +.P +If the result overflows, +a range error occurs, +and the functions return +.BR HUGE_VAL , +.BR HUGE_VALF , +or +.BR HUGE_VALL , +respectively, with a sign the same as +.IR x . +.P +If the result underflows, +a range error occurs, +and the functions return zero, with a sign the same as +.IR x . +.SH ERRORS +See +.BR math_error (7) +for information on how to determine whether an error has occurred +when calling these functions. +.P +The following errors can occur: +.TP +Range error, overflow +.\" .I errno +.\" is set to +.\" .BR ERANGE . +An overflow floating-point exception +.RB ( FE_OVERFLOW ) +is raised. +.TP +Range error, underflow +.I errno +is set to +.BR ERANGE . +An underflow floating-point exception +.RB ( FE_UNDERFLOW ) +is raised. +.SH ATTRIBUTES +For an explanation of the terms used in this section, see +.BR attributes (7). +.TS +allbox; +lbx lb lb +l l l. +Interface Attribute Value +T{ +.na +.nh +.BR scalbn (), +.BR scalbnf (), +.BR scalbnl (), +.BR scalbln (), +.BR scalblnf (), +.BR scalblnl () +T} Thread safety MT-Safe +.TE +.SH STANDARDS +C11, POSIX.1-2008. +.SH HISTORY +glibc 2.1. +C99, POSIX.1-2001. +.SH HISTORY +These functions differ from the obsolete functions described in +.BR 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 +.BR scalb (3) +have a second argument of type +.IR double . +.SH NOTES +If +.B FLT_RADIX +equals 2 (which is usual), then +.BR scalbn () +is equivalent to +.BR ldexp (3). +.SH BUGS +Before glibc 2.20, +.\" https://www.sourceware.org/bugzilla/show_bug.cgi?id=6803 +these functions did not set +.I errno +for range errors. +.SH SEE ALSO +.BR ldexp (3), +.BR scalb (3) |