.\" Copyright (c) 2011 Steven G. Kargl. .\" .\" Redistribution and use in source and binary forms, with or without .\" modification, are permitted provided that the following conditions .\" are met: .\" 1. Redistributions of source code must retain the above copyright .\" notice, this list of conditions and the following disclaimer. .\" 2. Redistributions in binary form must reproduce the above copyright .\" notice, this list of conditions and the following disclaimer in the .\" documentation and/or other materials provided with the distribution. .\" .\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE .\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF .\" SUCH DAMAGE. .\" .\" $FreeBSD$ .\" .Dd March 12, 2011 .Dt SINCOS 3 .Os .Sh NAME .Nm sincos , .Nm sincosf , .Nm sincosl .Nd sine and cosine functions .Sh LIBRARY .Lb libm .Sh SYNOPSIS .In math.h .Ft void .Fn sincos "double x" "double *s" "double *c" .Ft void .Fn sincosf "float x" "float *s" "float *c" .Ft void .Fn sincosl "long double x" "long double *s" "long double *c" .Sh DESCRIPTION The .Fn sincos , .Fn sincosf , and .Fn sincosl functions compute the sine and cosine of .Fa x . Using these functions allows argument reduction to occur only once instead of twice with individual invocations of .Fn sin and .Fn cos . Like .Fn sin and .Fn cos , a large magnitude argument may yield a result with little or no significance. .Sh RETURN VALUES Upon returning from .Fn sincos , .Fn sincosf , and .Fn sincosl , the memory pointed to by .Fa "*s" and .Fa "*c" are assigned the values of sine and cosine, respectively. .Sh SEE ALSO .Xr cos 3 , .Xr sin 3 .Sh HISTORY These functions were added to .Fx 11.2 to aid in writing various complex function contained in .St -isoC-99 .