1.\" Copyright (c) 1991, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" %sccs.include.redist.man% 5.\" 6.\" @(#)tanh.3 8.1 (Berkeley) 06/04/93 7.\" 8.Dd 9.Dt TANH 3 10.Os 11.Sh NAME 12.Nm tanh 13.Nd hyperbolic tangent function 14.Sh SYNOPSIS 15.Fd #include <math.h> 16.Ft double 17.Fn tanh "double x" 18.Sh DESCRIPTION 19The 20.Fn tanh 21function computes the hyperbolic tangent of 22.Fa x . 23For a discussion of error due to roundoff, see 24.Xr math 3 . 25.Sh RETURN VALUES 26The 27.Fn tanh 28function returns the hyperbolic tangent value. 29.Sh SEE ALSO 30.Xr acos 3 , 31.Xr asin 3 , 32.Xr atan 3 , 33.Xr atan2 3 , 34.Xr cos 3 , 35.Xr cosh 3 , 36.Xr sin 3 , 37.Xr sinh 3 , 38.Xr tan 3 , 39.Xr math 3 , 40.Sh STANDARDS 41The 42.Fn tanh 43function conforms to 44.St -ansiC . 45