mirror of https://github.com/mkerrisk/man-pages
116 lines
2.3 KiB
Groff
116 lines
2.3 KiB
Groff
.\" Copyright 2002 Walter Harms (walter.harms@informatik.uni-oldenburg.de)
|
|
.\" and Copyright 2008, Linux Foundation, written by Michael Kerrisk
|
|
.\" <mtk.manpages@gmail.com>
|
|
.\"
|
|
.\" %%%LICENSE_START(GPL_NOVERSION_ONELINE)
|
|
.\" Distributed under GPL
|
|
.\" %%%LICENSE_END
|
|
.\"
|
|
.TH SINCOS 3 2020-06-09 "GNU" "Linux Programmer's Manual"
|
|
.SH NAME
|
|
sincos, sincosf, sincosl \- calculate sin and cos simultaneously
|
|
.SH SYNOPSIS
|
|
.nf
|
|
.BR "#define _GNU_SOURCE" " /* See feature_test_macros(7) */"
|
|
.B #include <math.h>
|
|
.PP
|
|
.BI "void sincos(double " x ", double *" sin ", double *" cos );
|
|
.BI "void sincosf(float " x ", float *" sin ", float *" cos );
|
|
.BI "void sincosl(long double " x ", long double *" sin ", long double *" cos );
|
|
.fi
|
|
.PP
|
|
Link with \fI\-lm\fP.
|
|
.SH DESCRIPTION
|
|
Several applications need sine and cosine of the same angle
|
|
.IR x .
|
|
These functions compute both at the same time, and store the results in
|
|
.I *sin
|
|
and
|
|
.IR *cos .
|
|
Using this function can be more efficient than two separate calls to
|
|
.BR sin (3)
|
|
and
|
|
.BR cos (3).
|
|
.PP
|
|
If
|
|
.I x
|
|
is a NaN,
|
|
a NaN is returned in
|
|
.I *sin
|
|
and
|
|
.IR *cos .
|
|
.PP
|
|
If
|
|
.I x
|
|
is positive infinity or negative infinity,
|
|
a domain error occurs, and
|
|
a NaN is returned in
|
|
.I *sin
|
|
and
|
|
.IR *cos .
|
|
.SH RETURN VALUE
|
|
These functions return
|
|
.IR void .
|
|
.SH ERRORS
|
|
See
|
|
.BR math_error (7)
|
|
for information on how to determine whether an error has occurred
|
|
when calling these functions.
|
|
.PP
|
|
The following errors can occur:
|
|
.TP
|
|
Domain error: \fIx\fP is an infinity
|
|
.I errno
|
|
is set to
|
|
.BR EDOM
|
|
(but see BUGS).
|
|
An invalid floating-point exception
|
|
.RB ( FE_INVALID )
|
|
is raised.
|
|
.SH VERSIONS
|
|
These functions first appeared in glibc in version 2.1.
|
|
.SH ATTRIBUTES
|
|
For an explanation of the terms used in this section, see
|
|
.BR attributes (7).
|
|
.ad l
|
|
.nh
|
|
.TS
|
|
allbox;
|
|
lbx lb lb
|
|
l l l.
|
|
Interface Attribute Value
|
|
T{
|
|
.BR sincos (),
|
|
.BR sincosf (),
|
|
.BR sincosl ()
|
|
T} Thread safety MT-Safe
|
|
.TE
|
|
.hy
|
|
.ad
|
|
.sp 1
|
|
.SH CONFORMING TO
|
|
These functions are GNU extensions.
|
|
.SH NOTES
|
|
To see the performance advantage of
|
|
.BR sincos (),
|
|
it may be necessary to disable
|
|
.BR gcc (1)
|
|
built-in optimizations, using flags such as:
|
|
.PP
|
|
.in +4n
|
|
.EX
|
|
cc \-O \-lm \-fno\-builtin prog.c
|
|
.EE
|
|
.in
|
|
.SH BUGS
|
|
Before version 2.22, the glibc implementation did not set
|
|
.\" https://www.sourceware.org/bugzilla/show_bug.cgi?id=15467
|
|
.I errno
|
|
to
|
|
.B EDOM
|
|
when a domain error occurred.
|
|
.SH SEE ALSO
|
|
.BR cos (3),
|
|
.BR sin (3),
|
|
.BR tan (3)
|