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Diffstat (limited to 'man/man3/remainder.3')
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diff --git a/man/man3/remainder.3 b/man/man3/remainder.3 new file mode 100644 index 000000000..2a937ee48 --- /dev/null +++ b/man/man3/remainder.3 @@ -0,0 +1,234 @@ +'\" t +.\" Copyright 1993 David Metcalfe (david@prism.demon.co.uk) +.\" and Copyright 2008, Linux Foundation, written by Michael Kerrisk +.\" <mtk.manpages@gmail.com> +.\" +.\" SPDX-License-Identifier: Linux-man-pages-copyleft +.\" +.\" References consulted: +.\" Linux libc source code +.\" Lewine's _POSIX Programmer's Guide_ (O'Reilly & Associates, 1991) +.\" 386BSD man pages +.\" +.\" Modified 1993-07-24 by Rik Faith (faith@cs.unc.edu) +.\" Modified 2002-08-10 Walter Harms +.\" (walter.harms@informatik.uni-oldenburg.de) +.\" Modified 2003-11-18, 2004-10-05 aeb +.\" +.TH remainder 3 (date) "Linux man-pages (unreleased)" +.SH NAME +drem, dremf, dreml, remainder, remainderf, remainderl \- \ +floating-point remainder function +.SH LIBRARY +Math library +.RI ( libm ", " \-lm ) +.SH SYNOPSIS +.nf +.B #include <math.h> +.P +.BI "double remainder(double " x ", double " y ); +.BI "float remainderf(float " x ", float " y ); +.BI "long double remainderl(long double " x ", long double " y ); +.P +/* Obsolete synonyms */ +.BI "[[deprecated]] double drem(double " x ", double " y ); +.BI "[[deprecated]] float dremf(float " x ", float " y ); +.BI "[[deprecated]] long double dreml(long double " x ", long double " y ); +.fi +.P +.RS -4 +Feature Test Macro Requirements for glibc (see +.BR feature_test_macros (7)): +.RE +.P +.BR remainder (): +.nf + _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L + || _XOPEN_SOURCE >= 500 +.\" || _XOPEN_SOURCE && _XOPEN_SOURCE_EXTENDED + || /* Since glibc 2.19: */ _DEFAULT_SOURCE + || /* glibc <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE +.fi +.P +.BR remainderf (), +.BR remainderl (): +.nf + _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L + || /* Since glibc 2.19: */ _DEFAULT_SOURCE + || /* glibc <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE +.fi +.P +.BR drem (), +.BR dremf (), +.BR dreml (): +.nf + /* Since glibc 2.19: */ _DEFAULT_SOURCE + || /* glibc <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE +.fi +.SH DESCRIPTION +These +functions compute the remainder of dividing +.I x +by +.IR y . +The return value is +\fIx\fP\-\fIn\fP*\fIy\fP, +where +.I n +is the value +.IR "x\ /\ y" , +rounded to the nearest integer. +If the absolute value of +\fIx\fP\-\fIn\fP*\fIy\fP +is 0.5, +.I n +is chosen to be even. +.P +These functions are unaffected by the current rounding mode (see +.BR fenv (3)). +.P +The +.BR drem () +function does precisely the same thing. +.SH RETURN VALUE +On success, these +functions return the floating-point remainder, +\fIx\fP\-\fIn\fP*\fIy\fP. +If the return value is 0, it has the sign of +.IR x . +.P +If +.I x +or +.I y +is a NaN, a NaN is returned. +.P +If +.I x +is an infinity, +and +.I y +is not a NaN, +a domain error occurs, and +a NaN is returned. +.P +If +.I y +is zero, +.\" FIXME . Instead, glibc gives a domain error even if x is a NaN +and +.I x +is not a NaN, +.\" Interestingly, remquo(3) does not have the same problem. +a domain error occurs, and +a NaN is returned. +.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 +Domain error: \fIx\fP is an infinity and \fIy\fP is not a NaN +.I errno +is set to +.B EDOM +(but see BUGS). +An invalid floating-point exception +.RB ( FE_INVALID ) +is raised. +.IP +These functions do not set +.I errno +for this case. +.TP +Domain error: \fIy\fP is zero\" [XXX see bug above] and \fIx\fP is not a NaN +.I errno +is set to +.BR EDOM . +An invalid floating-point exception +.RB ( FE_INVALID ) +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 drem (), +.BR dremf (), +.BR dreml (), +.BR remainder (), +.BR remainderf (), +.BR remainderl () +T} Thread safety MT-Safe +.TE +.SH STANDARDS +.\" IEC 60559. +.TP +.BR remainder () +.TQ +.BR remainderf () +.TQ +.BR remainderl () +C11, POSIX.1-2008. +.TP +.BR drem () +.TQ +.BR dremf () +.TQ +.BR dreml () +None. +.SH HISTORY +.\" IEC 60559. +.TP +.BR remainder () +.TQ +.BR remainderf () +.TQ +.BR remainderl () +C99, POSIX.1-2001. +.TP +.BR drem () +4.3BSD. +.TP +.BR dremf () +.TQ +.BR dreml () +Tru64, glibc2. +.SH BUGS +Before glibc 2.15, +.\" https://www.sourceware.org/bugzilla/show_bug.cgi?id=6779 +the call +.P +.in +4n +.EX +remainder(nan(""), 0); +.EE +.in +.P +returned a NaN, as expected, but wrongly caused a domain error. +Since glibc 2.15, a silent NaN (i.e., no domain error) is returned. +.P +Before glibc 2.15, +.\" https://www.sourceware.org/bugzilla/show_bug.cgi?id=6783 +.I errno +was not set to +.B EDOM +for the domain error that occurs when +.I x +is an infinity and +.I y +is not a NaN. +.SH EXAMPLES +The call "remainder(29.0, 3.0)" returns \-1. +.SH SEE ALSO +.BR div (3), +.BR fmod (3), +.BR remquo (3) |