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diff --git a/man3/tanh.3 b/man3/tanh.3 new file mode 100644 index 0000000..dc4d8fc --- /dev/null +++ b/man3/tanh.3 @@ -0,0 +1,106 @@ +'\" t +.\" Copyright 1993 David Metcalfe (david@prism.demon.co.uk) +.\" and Copyright 2008, Linux Foundation, written by Michael Kerrisk +.\" <mtk.manpages@gmail.com> +.\" +.\" SPDX-License-Identifier: Linux-man-pages-copyleft +.\" +.\" References consulted: +.\" Linux libc source code +.\" Lewine's _POSIX Programmer's Guide_ (O'Reilly & Associates, 1991) +.\" 386BSD man pages +.\" Modified 1993-07-24 by Rik Faith (faith@cs.unc.edu) +.\" Modified 2002-07-27 by Walter Harms +.\" (walter.harms@informatik.uni-oldenburg.de) +.\" +.TH tanh 3 2023-07-20 "Linux man-pages 6.05.01" +.SH NAME +tanh, tanhf, tanhl \- hyperbolic tangent function +.SH LIBRARY +Math library +.RI ( libm ", " \-lm ) +.SH SYNOPSIS +.nf +.B #include <math.h> +.PP +.BI "double tanh(double " x ); +.BI "float tanhf(float " x ); +.BI "long double tanhl(long double " x ); +.fi +.PP +.RS -4 +Feature Test Macro Requirements for glibc (see +.BR feature_test_macros (7)): +.RE +.PP +.BR tanhf (), +.BR tanhl (): +.nf + _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L + || /* Since glibc 2.19: */ _DEFAULT_SOURCE + || /* glibc <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE +.fi +.SH DESCRIPTION +These functions return the hyperbolic tangent of +.IR x , +which +is defined mathematically as: +.PP +.nf + tanh(x) = sinh(x) / cosh(x) +.fi +.SH RETURN VALUE +On success, these functions return the hyperbolic tangent of +.IR x . +.PP +If +.I x +is a NaN, a NaN is returned. +.PP +If +.I x +is +0 (\-0), +0 (\-0) is returned. +.PP +If +.I x +is positive infinity (negative infinity), ++1 (\-1) is returned. +.\" +.\" POSIX.1-2001 documents an optional range error (underflow) +.\" for subnormal x; +.\" glibc 2.8 does not do this. +.SH ERRORS +No errors occur. +.SH ATTRIBUTES +For an explanation of the terms used in this section, see +.BR attributes (7). +.TS +allbox; +lbx lb lb +l l l. +Interface Attribute Value +T{ +.na +.nh +.BR tanh (), +.BR tanhf (), +.BR tanhl () +T} Thread safety MT-Safe +.TE +.sp 1 +.SH STANDARDS +C11, POSIX.1-2008. +.SH HISTORY +C99, POSIX.1-2001. +.PP +The variant returning +.I double +also conforms to +SVr4, 4.3BSD, C89. +.SH SEE ALSO +.BR acosh (3), +.BR asinh (3), +.BR atanh (3), +.BR cosh (3), +.BR ctanh (3), +.BR sinh (3) |