1 .\" Copyright 1993 David Metcalfe (david@prism.demon.co.uk)
2 .\" and Copyright 2008, Linux Foundation, written by Michael Kerrisk
3 .\" <mtk.manpages@gmail.com>
5 .\" %%%LICENSE_START(VERBATIM)
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11 .\" manual under the conditions for verbatim copying, provided that the
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13 .\" permission notice identical to this one.
15 .\" Since the Linux kernel and libraries are constantly changing, this
16 .\" manual page may be incorrect or out-of-date. The author(s) assume no
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27 .\" References consulted:
28 .\" Linux libc source code
29 .\" Lewine's _POSIX Programmer's Guide_ (O'Reilly & Associates, 1991)
31 .\" Modified 1993-07-24 by Rik Faith (faith@cs.unc.edu)
32 .\" Modified 1996-06-08 by aeb
33 .\" Modified 2002-07-27 by Walter Harms
34 .\" (walter.harms@informatik.uni-oldenburg.de)
36 .TH COSH 3 2010-09-20 "" "Linux Programmer's Manual"
38 cosh, coshf, coshl \- hyperbolic cosine function
43 .BI "double cosh(double " x );
45 .BI "float coshf(float " x );
47 .BI "long double coshl(long double " x );
53 Feature Test Macro Requirements for glibc (see
54 .BR feature_test_macros (7)):
61 _BSD_SOURCE || _SVID_SOURCE || _XOPEN_SOURCE\ >=\ 600 || _ISOC99_SOURCE ||
62 _POSIX_C_SOURCE\ >=\ 200112L;
71 function returns the hyperbolic cosine of \fIx\fP, which
72 is defined mathematically as:
75 cosh(x) = (exp(x) + exp(\-x)) / 2
78 On success, these functions return the hyperbolic cosine of
83 is a NaN, a NaN is returned.
87 is +0 or \-0, 1 is returned.
91 is positive infinity or negative infinity,
92 positive infinity is returned.
94 If the result overflows,
96 and the functions return
105 for information on how to determine whether an error has occurred
106 when calling these functions.
108 The following errors can occur:
110 Range error: result overflow
114 An overflow floating-point exception
119 The variant returning
124 In glibc version 2.3.4 and earlier,
125 an overflow floating-point
127 exception is not raised when an overflow occurs.