<HTML>
<HEAD>
<TITLE>Units.pm</TITLE>
<LINK REL="stylesheet" HREF="../html/docs.css" TYPE="text/css">
<LINK REV="made" HREF="mailto:">
</HEAD>
<BODY>
<TABLE BORDER=0 CELLPADDING=0 CELLSPACING=0 WIDTH=100%>
<TR><TD CLASS=block VALIGN=MIDDLE WIDTH=100% BGCOLOR="#cccccc">
<FONT SIZE=+1><STRONG><P CLASS=block> Units.pm</P></STRONG></FONT>
</TD></TR>
</TABLE>
<A NAME="__index__"></A>
<!-- INDEX BEGIN -->
<UL>
<LI><A HREF="#name">NAME</A></LI>
<LI><A HREF="#synopsis">SYNOPSIS</A></LI>
<LI><A HREF="#description">DESCRIPTION</A></LI>
<UL>
<UL>
<LI><A HREF="#units( [units] )">units( [UNITS] )</A></LI>
<LI><A HREF="#dsin">dsin</A></LI>
<LI><A HREF="#dcos">dcos</A></LI>
<LI><A HREF="#tan">tan</A></LI>
<LI><A HREF="#sec">sec</A></LI>
<LI><A HREF="#csc">csc</A></LI>
<LI><A HREF="#cot">cot</A></LI>
<LI><A HREF="#asin">asin</A></LI>
<LI><A HREF="#acos">acos</A></LI>
<LI><A HREF="#atan">atan</A></LI>
<LI><A HREF="#asec">asec</A></LI>
<LI><A HREF="#acsc">acsc</A></LI>
<LI><A HREF="#acot">acot</A></LI>
<LI><A HREF="#sinh">sinh</A></LI>
<LI><A HREF="#cosh">cosh</A></LI>
<LI><A HREF="#tanh">tanh</A></LI>
<LI><A HREF="#sech">sech</A></LI>
<LI><A HREF="#csch">csch</A></LI>
<LI><A HREF="#coth">coth</A></LI>
<LI><A HREF="#asinh">asinh</A></LI>
<LI><A HREF="#acosh">acosh</A></LI>
<LI><A HREF="#atanh">atanh</A></LI>
<LI><A HREF="#asech">asech</A></LI>
<LI><A HREF="#acsch">acsch</A></LI>
<LI><A HREF="#acoth">acoth</A></LI>
</UL>
</UL>
<LI><A HREF="#history">HISTORY</A></LI>
<LI><A HREF="#bugs">BUGS</A></LI>
<LI><A HREF="#author">AUTHOR</A></LI>
</UL>
<!-- INDEX END -->
<HR>
<P>
<H1><A NAME="name">NAME</A></H1>
<PRE>
Math::Trig::Units - Inverse and hyperbolic trigonemetric Functions
in degrees, radians or gradians.</PRE>
<P>
<HR>
<H1><A NAME="synopsis">SYNOPSIS</A></H1>
<PRE>
use Math::Trig::Units qw(dsin dcos tan sec csc cot
asin acos atan asec acsc acot
sinh cosh tanh sech csch coth
asinh acosh atanh asech acsch acoth
deg_to_rad rad_to_deg
grad_to_rad rad_to_grad
deg_to_grad grad_to_deg
units );
$v = dsin($x);
$v = dcos($x);
$v = tan($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);
$degrees = rad_to_deg($radians);
$radians = deg_to_rad($degrees);
$degrees = grad_to_deg($gradians);
$gradians = deg_to_grad($degrees);
$radians = grad_to_rad($gradians);
$gradians = rad_to_grad($radians);</PRE>
<PRE>
# set radians instead of degrees (default)
Math::Trig::Units::units('radians');
# set gradians as units
Math::Trig::Units::units('gradians');
# set degrees as units
Math::Trig::Units::units('degrees');
# return current unit setting
$units = Math::Trig::Units::units();</PRE>
<P>
<HR>
<H1><A NAME="description">DESCRIPTION</A></H1>
<P>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 where an illegal divion by zero would occur
will cause infinity to be returned. Infinity is Perl's version of this.</P>
<P>This module implements the functions in radians by default. You set the
units via the units sub:</P>
<PRE>
# set radians as units (default)
Math::Trig::Units::units('radians');
# set gradians as units
Math::Trig::Units::units('gradians');
# set degrees as units
Math::Trig::Units::units('degrees');
# return current unit setting
$units = Math::Trig::Units::units();</PRE>
<P>To avoid redefining the internal <CODE>sin()</CODE> and <CODE>cos()</CODE> functions this module
calls the functions <CODE>dsin()</CODE> and dcos().</P>
<P>
<H3><A NAME="units( [units] )">units( [UNITS] )</A></H3>
<P>Set or get the units. Options are 'radians', 'degrees', 'gradians' and are
case insensitive. When called without an argument this function returns the
current units setting. Alternatively you can call the subclasses:</P>
<PRE>
Math::Trig::Degree
Math::Trig::Radian
Math::Trig::Gradian</PRE>
<P>
<H3><A NAME="dsin">dsin</A></H3>
<P>returns sin of real argument.</P>
<P>
<H3><A NAME="dcos">dcos</A></H3>
<P>returns cos of real argument.</P>
<P>
<H3><A NAME="tan">tan</A></H3>
<P>returns tangent of real argument.</P>
<P>
<H3><A NAME="sec">sec</A></H3>
<P>returns secant of real argument.</P>
<P>
<H3><A NAME="csc">csc</A></H3>
<P>returns cosecant of real argument.</P>
<P>
<H3><A NAME="cot">cot</A></H3>
<P>returns cotangent of real argument.</P>
<P>
<H3><A NAME="asin">asin</A></H3>
<P>returns inverse sine of real argument.</P>
<P>
<H3><A NAME="acos">acos</A></H3>
<P>returns inverse cosine of real argument.</P>
<P>
<H3><A NAME="atan">atan</A></H3>
<P>returns inverse tangent of real argument.</P>
<P>
<H3><A NAME="asec">asec</A></H3>
<P>returns inverse secant of real argument.</P>
<P>
<H3><A NAME="acsc">acsc</A></H3>
<P>returns inverse cosecant of real argument.</P>
<P>
<H3><A NAME="acot">acot</A></H3>
<P>returns inverse cotangent of real argument.</P>
<P>
<H3><A NAME="sinh">sinh</A></H3>
<P>returns hyperbolic sine of real argument.</P>
<P>
<H3><A NAME="cosh">cosh</A></H3>
<P>returns hyperbolic cosine of real argument.</P>
<P>
<H3><A NAME="tanh">tanh</A></H3>
<P>returns hyperbolic tangent of real argument.</P>
<P>
<H3><A NAME="sech">sech</A></H3>
<P>returns hyperbolic secant of real argument.</P>
<P>
<H3><A NAME="csch">csch</A></H3>
<P>returns hyperbolic cosecant of real argument.</P>
<P>
<H3><A NAME="coth">coth</A></H3>
<P>returns hyperbolic cotangent of real argument.</P>
<P>
<H3><A NAME="asinh">asinh</A></H3>
<P>returns inverse hyperbolic sine of real argument.</P>
<P>
<H3><A NAME="acosh">acosh</A></H3>
<P>returns inverse hyperbolic cosine of real argument.</P>
<P>(positive value only)</P>
<P>
<H3><A NAME="atanh">atanh</A></H3>
<P>returns inverse hyperbolic tangent of real argument.</P>
<P>
<H3><A NAME="asech">asech</A></H3>
<P>returns inverse hyperbolic secant of real argument.</P>
<P>(positive value only)</P>
<P>
<H3><A NAME="acsch">acsch</A></H3>
<P>returns inverse hyperbolic cosecant of real argument.</P>
<P>
<H3><A NAME="acoth">acoth</A></H3>
<P>returns inverse hyperbolic cotangent of real argument.</P>
<P>
<HR>
<H1><A NAME="history">HISTORY</A></H1>
<P>Modification of Math::Trig by request from stefan_k.</P>
<P>
<HR>
<H1><A NAME="bugs">BUGS</A></H1>
<P>All known ones have been fixed (see changes). Let me know if you find one.</P>
<P>
<HR>
<H1><A NAME="author">AUTHOR</A></H1>
<P>Initial Version John A.R. Williams <<A HREF="mailto:J.A.R.Williams@aston.ac.uk">J.A.R.Williams@aston.ac.uk</A>>
Bug fixes and many additonal functions Jason Smith <<A HREF="mailto:smithj4@rpi.edu">smithj4@rpi.edu</A>>
This version James Freeman <<A HREF="mailto:james.freeman@id3.org.uk">james.freeman@id3.org.uk</A>></P>
<TABLE BORDER=0 CELLPADDING=0 CELLSPACING=0 WIDTH=100%>
<TR><TD CLASS=block VALIGN=MIDDLE WIDTH=100% BGCOLOR="#cccccc">
<FONT SIZE=+1><STRONG><P CLASS=block> Units.pm</P></STRONG></FONT>
</TD></TR>
</TABLE>
</BODY>
</HTML>