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diff --git a/man/man3/atanh.3 b/man/man3/atanh.3 new file mode 100644 index 000000000..136a501b7 --- /dev/null +++ b/man/man3/atanh.3 @@ -0,0 +1,154 @@ +'\" 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 atanh 3 (date) "Linux man-pages (unreleased)" +.SH NAME +atanh, atanhf, atanhl \- inverse hyperbolic tangent function +.SH LIBRARY +Math library +.RI ( libm ", " \-lm ) +.SH SYNOPSIS +.nf +.B #include <math.h> +.P +.BI "double atanh(double " x ); +.BI "float atanhf(float " x ); +.BI "long double atanhl(long double " x ); +.P +.fi +.RS -4 +Feature Test Macro Requirements for glibc (see +.BR feature_test_macros (7)): +.RE +.P +.BR atanh (): +.nf + _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L + || _XOPEN_SOURCE >= 500 +.\" || _XOPEN_SOURCE && _XOPEN_SOURCE_EXTENDED + || /* Since glibc 2.19: */ _DEFAULT_SOURCE + || /* glibc <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE +.fi +.P +.BR atanhf (), +.BR atanhl (): +.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 calculate the inverse hyperbolic tangent of +.IR x ; +that is the value whose hyperbolic tangent is +.IR x . +.SH RETURN VALUE +On success, these functions return the inverse hyperbolic tangent of +.IR x . +.P +If +.I x +is a NaN, a NaN is returned. +.P +If +.I x +is +0 (\-0), +0 (\-0) is returned. +.P +If +.I x +is +1 or \-1, +a pole error occurs, +and the functions return +.BR HUGE_VAL , +.BR HUGE_VALF , +or +.BR HUGE_VALL , +respectively, with the mathematically correct sign. +.P +If the absolute value of +.I x +is greater than 1, +a domain error occurs, +and a NaN is returned. +.\" +.\" POSIX.1-2001 documents an optional range error for subnormal x; +.\" glibc 2.8 does not do this. +.SH ERRORS +See +.BR math_error (7) +for information on how to determine whether an error has occurred +when calling these functions. +.P +The following errors can occur: +.TP +Domain error: \fIx\fP less than \-1 or greater than +1 +.I errno +is set to +.BR EDOM . +An invalid floating-point exception +.RB ( FE_INVALID ) +is raised. +.TP +Pole error: \fIx\fP is +1 or \-1 +.I errno +is set to +.B ERANGE +(but see BUGS). +A divide-by-zero floating-point exception +.RB ( FE_DIVBYZERO ) +is raised. +.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 atanh (), +.BR atanhf (), +.BR atanhl () +T} Thread safety MT-Safe +.TE +.SH STANDARDS +C11, POSIX.1-2008. +.SH HISTORY +C99, POSIX.1-2001. +.P +The variant returning +.I double +also conforms to +SVr4, 4.3BSD. +.SH BUGS +In glibc 2.9 and earlier, +.\" Bug: https://www.sourceware.org/bugzilla/show_bug.cgi?id=6759 +.\" This can be seen in sysdeps/ieee754/k_standard.c +when a pole error occurs, +.I errno +is set to +.B EDOM +instead of the POSIX-mandated +.BR ERANGE . +Since glibc 2.10, glibc does the right thing. +.SH SEE ALSO +.BR acosh (3), +.BR asinh (3), +.BR catanh (3), +.BR cosh (3), +.BR sinh (3), +.BR tanh (3) |