# NAME

``    Math::Trig - Inverse and hyperbolic trigonemetric Functions``

# SYNOPSIS

``````    use Math::Trig qw(tan sec csc cot asin acos atan asec acsc acot sinh cosh tanh sech csch coth asinh acosh atanh asech acsch acoth);
\$v=tan(\$x);
\$v=sec(\$x);
\$v=csc(\$x);
\$v=cot(\$x);
\$v=asin(\$x);
\$v=acos(\$x);
\$v=atan(\$x);
\$v=asec(\$x);
\$v=acsc(\$x);
\$v=acot(\$x);
\$v=sinh(\$x);
\$v=cosh(\$x);
\$v=tanh(\$x);
\$v=sech(\$x);
\$v=csch(\$x);
\$v=coth(\$x);
\$v=asinh(\$x);
\$v=acosh(\$x);
\$v=atanh(\$x);
\$v=asech(\$x);
\$v=acsch(\$x);
\$v=acoth(\$x);``````

# DESCRIPTION

This module exports the missing inverse and hyperbolic trigonometric functions of real numbers. The inverse functions return values cooresponding to the principal values. Specifying an argument outside of the domain of the function will cause undef to be returned.

tan returns tangent of real argument.
sec returns secant of real argument.
csc returns cosecant of real argument.
cot returns cotangent of real argument.
asin returns inverse sine of real argument.
acos returns inverse cosine of real argument.
atan returns inverse tangent of real argument.
asec returns inverse secant of real argument.
acsc returns inverse cosecant of real argument.
acot returns inverse cotangent of real argument.
sinh returns hyperbolic sine of real argument.
cosh returns hyperbolic cosine of real argument.
tanh returns hyperbolic tangent of real argument.
sech returns hyperbolic secant of real argument.
csch returns hyperbolic cosecant of real argument.
coth returns hyperbolic cotangent of real argument.
asinh returns inverse hyperbolic sine of real argument.
acosh returns inverse hyperbolic cosine of real argument.

(positive value only)

atanh returns inverse hyperbolic tangent of real argument.
asech returns inverse hyperbolic secant of real argument.

(positive value only)

acsch returns inverse hyperbolic cosecant of real argument.
acoth returns inverse hyperbolic cotangent of real argument.

# HISTORY

\$Log: Trig.pm,v \$ Revision 1.4 1997/02/26 17:28:42 willijar Revised verions from Jason Smith fixing error in sinh and cosh which where the wrong way round. jason also provided many new functions to complete the set. Also fixed bug which prevented pod2man correctly creating man page

Revision 1.2 1995/12/28 16:32:37 willijar Moved hyoerbolic functions into here.

Revision 1.1 1995/12/24 16:06:26 willijar Initial revision

# BUGS

Some functions may return undef even within their domain. It will usually only occur very close to a domain boundary or when evaluating a very large or small argument though. This is usually caused by things like internally adding 1 to 1e20 while evaluating the function with the other trigonometric and exponential functions.

Let me know about any others.

I welcome additions such as the inverse trigonemetric functions and the complex versions of the functions to be included in this module.

# AUTHOR

Initial Version John A.R. Williams <J.A.R.Williams@aston.ac.uk> Bug fixes and many additonal functions Jason Smith <smithj4@rpi.edu>

2 POD Errors

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