1.\" Copyright (c) 1991 The Regents of the University of California. 2.\" All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. --- 12 unchanged lines hidden (view full) --- 21.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26.\" SUCH DAMAGE. 27.\" 28.\" from: @(#)atan.3 5.1 (Berkeley) 5/2/91 |
29.\" $FreeBSD: head/lib/msun/man/atan.3 181074 2008-07-31 22:41:26Z das $ |
30.\" |
31.Dd July 31, 2008 |
32.Dt ATAN 3 33.Os 34.Sh NAME 35.Nm atan , |
36.Nm atanf , 37.Nm atanl |
38.Nd arc tangent functions of one variable 39.Sh LIBRARY 40.Lb libm 41.Sh SYNOPSIS 42.In math.h 43.Ft double 44.Fn atan "double x" 45.Ft float 46.Fn atanf "float x" |
47.Ft long double 48.Fn atanl "long double x" |
49.Sh DESCRIPTION 50The |
51.Fn atan , 52.Fn atanf , 53and 54.Fn atanl |
55functions compute the principal value of the arc tangent of 56.Fa x . |
57.Sh RETURN VALUES |
58These functions return the arc tangent in the range |
59.Bk -words 60.Bq -\*(Pi/2 , +\*(Pi/2 61.Ek 62radians. 63.Sh SEE ALSO 64.Xr acos 3 , 65.Xr asin 3 , 66.Xr atan2 3 , 67.Xr cos 3 , 68.Xr cosh 3 , 69.Xr math 3 , 70.Xr sin 3 , 71.Xr sinh 3 , 72.Xr tan 3 , 73.Xr tanh 3 74.Sh STANDARDS 75The |
76.Fn atan , 77.Fn atanf , 78and 79.Fn atanl 80functions conform to 81.St -isoC-99 . |