1*05a0b428SJohn Marino.\" $OpenBSD: atan.3,v 1.13 2013/06/05 03:40:26 tedu Exp $ 2*05a0b428SJohn Marino.\" Copyright (c) 1991 The Regents of the University of California. 3*05a0b428SJohn Marino.\" All rights reserved. 4*05a0b428SJohn Marino.\" 5*05a0b428SJohn Marino.\" Redistribution and use in source and binary forms, with or without 6*05a0b428SJohn Marino.\" modification, are permitted provided that the following conditions 7*05a0b428SJohn Marino.\" are met: 8*05a0b428SJohn Marino.\" 1. Redistributions of source code must retain the above copyright 9*05a0b428SJohn Marino.\" notice, this list of conditions and the following disclaimer. 10*05a0b428SJohn Marino.\" 2. Redistributions in binary form must reproduce the above copyright 11*05a0b428SJohn Marino.\" notice, this list of conditions and the following disclaimer in the 12*05a0b428SJohn Marino.\" documentation and/or other materials provided with the distribution. 13*05a0b428SJohn Marino.\" 3. Neither the name of the University nor the names of its contributors 14*05a0b428SJohn Marino.\" may be used to endorse or promote products derived from this software 15*05a0b428SJohn Marino.\" without specific prior written permission. 16*05a0b428SJohn Marino.\" 17*05a0b428SJohn Marino.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18*05a0b428SJohn Marino.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19*05a0b428SJohn Marino.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20*05a0b428SJohn Marino.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21*05a0b428SJohn Marino.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22*05a0b428SJohn Marino.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23*05a0b428SJohn Marino.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24*05a0b428SJohn Marino.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25*05a0b428SJohn Marino.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26*05a0b428SJohn Marino.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27*05a0b428SJohn Marino.\" SUCH DAMAGE. 28*05a0b428SJohn Marino.\" 29*05a0b428SJohn Marino.\" from: @(#)atan.3 5.1 (Berkeley) 5/2/91 30*05a0b428SJohn Marino.\" 31*05a0b428SJohn Marino.Dd $Mdocdate: June 5 2013 $ 32*05a0b428SJohn Marino.Dt ATAN 3 33*05a0b428SJohn Marino.Os 34*05a0b428SJohn Marino.Sh NAME 35*05a0b428SJohn Marino.Nm atan , 36*05a0b428SJohn Marino.Nm atanf , 37*05a0b428SJohn Marino.Nm atanl 38*05a0b428SJohn Marino.Nd arc tangent functions of one variable 39*05a0b428SJohn Marino.Sh SYNOPSIS 40*05a0b428SJohn Marino.In math.h 41*05a0b428SJohn Marino.Ft double 42*05a0b428SJohn Marino.Fn atan "double x" 43*05a0b428SJohn Marino.Ft float 44*05a0b428SJohn Marino.Fn atanf "float x" 45*05a0b428SJohn Marino.Ft long double 46*05a0b428SJohn Marino.Fn atanl "long double x" 47*05a0b428SJohn Marino.Sh DESCRIPTION 48*05a0b428SJohn MarinoThe 49*05a0b428SJohn Marino.Fn atan 50*05a0b428SJohn Marinofunction computes the principal value of the arc tangent of 51*05a0b428SJohn Marino.Fa x 52*05a0b428SJohn Marinoin the range 53*05a0b428SJohn Marino.Bk -words 54*05a0b428SJohn Marino.Bq -\*(Pi/2 , +\*(Pi/2 . 55*05a0b428SJohn Marino.Ek 56*05a0b428SJohn MarinoThe 57*05a0b428SJohn Marino.Fn atanf 58*05a0b428SJohn Marinofunction is a single precision version of 59*05a0b428SJohn Marino.Fn atan . 60*05a0b428SJohn MarinoThe 61*05a0b428SJohn Marino.Fn atanl 62*05a0b428SJohn Marinofunction is an extended precision version of 63*05a0b428SJohn Marino.Fn atan . 64*05a0b428SJohn Marino.Sh SEE ALSO 65*05a0b428SJohn Marino.Xr acos 3 , 66*05a0b428SJohn Marino.Xr asin 3 , 67*05a0b428SJohn Marino.Xr atan2 3 , 68*05a0b428SJohn Marino.Xr cos 3 , 69*05a0b428SJohn Marino.Xr cosh 3 , 70*05a0b428SJohn Marino.Xr sin 3 , 71*05a0b428SJohn Marino.Xr sinh 3 , 72*05a0b428SJohn Marino.Xr tan 3 , 73*05a0b428SJohn Marino.Xr tanh 3 74