man3/sincos.3

.\" Copyright 2002 Walter Harms (walter.harms@informatik.uni-oldenburg.de)
.\" Distributed under GPL, 2002-07-27 Walter Harms
.\" and Copyright 2008, Linux Foundation, written by Michael Kerrisk
.\"     <mtk.manpages@gmail.com>
.\"
.TH SINCOS 3  2008-08-11 "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>
.sp
.BI "void sincos(double " x ", double *" sin ", double *" cos );
.br
.BI "void sincosf(float " x ", float *" sin ", float *" cos );
.br
.BI "void sincosl(long double " x ", long double *" sin ", long double *" cos );
.fi
.sp
Link with \fI\-lm\fP.
.SH DESCRIPTION
Several applications need sine and cosine of the same angle
.IR x .
This function computes both at the same time, and stores the results in
.I *sin
and
.IR *cos .

If
.I x
is a NaN,
a NaN is returned in
.I *sin
and
.IR *cos .

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 .
An invalid floating-point exception
.RB ( FE_INVALID )
is raised.
.PP
These functions do not set
.IR errno .
.\" FIXME . Is it intentional that these functions do not set errno?
.\" sin() and cos() also don't set errno; bugs have been raised for
.\" those functions.
.SH VERSIONS
These functions first appeared in glibc in version 2.1.
.SH "CONFORMING TO"
This function is a GNU extension.
.SH "SEE ALSO"
.BR cos (3),
.BR sin (3),
.BR tan (3)