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<html><head><title>Math::Trig (Perl in a Nutshell, 2nd Edition)</title><link rel="stylesheet" type="text/css" href="../style/style1.css" /><meta name="DC.Creator" content="Stephen Spainhour" /><meta name="DC.Format" content="text/xml" scheme="MIME" /><meta name="DC.Language" content="en-US" /><meta name="DC.Publisher" content="O'Reilly & Associates, Inc." /><meta name="DC.Source" scheme="ISBN" content="0596002416L" /><meta name="DC.Subject.Keyword" content="stuff" /><meta name="DC.Title" content="Perl in a Nutshell, 2nd Edition" /><meta name="DC.Type" content="Text.Monograph" /></head><body bgcolor="#ffffff"><img src="gifs/smbanner.gif" usemap="#banner-map" border="0" alt="Book Home" /><map name="banner-map"><area shape="rect" coords="1,-2,616,66" href="index.htm" alt="Java and XSLT" /><area shape="rect" coords="629,-11,726,25" href="jobjects/fsearch.htm" alt="Search this book" /></map><div class="navbar"><table width="684" border="0"><tr><td align="left" valign="top" width="228"><a href="ch08_146.htm"><img src="../gifs/txtpreva.gif" alt="Previous" border="0" /></a></td><td align="center" valign="top" width="228" /><td align="right" valign="top" width="228"><a href="ch08_148.htm"><img src="../gifs/txtnexta.gif" alt="Next" border="0" /></a></td></tr></table></div><h2 class="sect1">8.147. Math::Trig</h2><p><a name="INDEX-1501" />Defines many trigonometric functionsnot defined by the core Perl, plus the constant <tt class="literal">pi</tt>and some additional functions for converting angles. For example:</p><blockquote><pre class="code">use Math::Trig; $x = tan(0.9);$halfpi = pi/2;</pre></blockquote><p>The following functions are defined. A slash (<tt class="literal">/</tt>)between two functions means the values are aliases.</p><dl><dt><b><tt class="literal">acsc/acosec</tt>, <tt class="literal">asec</tt>, <tt class="literal">acot/acotan</tt></b></dt><dd>Arcus cofunctions of sine, cosine, and tangent</p></dd><dt><b><tt class="literal">acsch/acosech</tt>, <tt class="literal">asech</tt>, <tt class="literal">acoth/acotanh</tt></b></dt><dd>Arcus cofunctions of hyperbolic sine, cosine, and tangent</p></dd><dt><b><tt class="literal">asin</tt>, <tt class="literal">acos</tt>, <tt class="literal">atan</tt></b></dt><dd>Arcus (inverse) functions of sine, cosine, and tangent</p></dd><dt><b><tt class="literal">asinh</tt>, <tt class="literal">acosh</tt>, <tt class="literal">atanh</tt></b></dt><dd>Arcus functions of hyperbolic sine, cosine, and tangent</p></dd><dt><b><tt class="literal">atan2(</tt><em class="replaceable">y</em><tt class="literal">,</tt> <em class="replaceable">x</em><tt class="literal">)</tt></b></dt><dd>Principal value of arc tangent of<em class="replaceable"><tt>y</em>/<em class="replaceable">x</tt></em></p></dd><dt><b><tt class="literal">csc/cosec</tt>, <tt class="literal">sec</tt>, <tt class="literal">cot/cotan</tt></b></dt><dd>Cofunctions of sine, cosine, and tangent</p></dd><dt><b><tt class="literal">csch/cosech</tt>, <tt class="literal">sech</tt>, <tt class="literal">coth/cotanh</tt></b></dt><dd>Cofunctions of hyperbolic sine, cosine, and tangent</p></dd><dt><b><tt class="literal">deg2rad</tt></b></dt><dd>Degrees to radians</p></dd><dt><b><tt class="literal">deg2grad</tt></b></dt><dd>Degrees to gradians</p></dd><dt><b><tt class="literal">grad2deg</tt></b></dt><dd>Gradians to degrees</p></dd><dt><b><tt class="literal">grad2rad</tt></b></dt><dd>Gradians to radians</p></dd><dt><b><tt class="literal">pi</tt></b></dt><dd>The trigonometric constant <img src="figs/U03C0.gif" alt="Figure 8.147" width="10" height="8" /></p></dd><dt><b><tt class="literal">rad2deg</tt></b></dt><dd>Radians to degrees</p></dd><dt><b><tt class="literal">rad2grad</tt></b></dt><dd>Radians to gradians</p></dd><dt><b><tt class="literal">sinh</tt>, <tt class="literal">cosh</tt>, <tt class="literal">tanh</tt></b></dt><dd>Hyperbolic sine, cosine, and tangent</p></dd><dt><b><tt class="literal">tan</tt></b></dt><dd>Tangent<a name="INDEX-1502" /></p></dd></dl><hr width="684" align="left" /><div class="navbar"><table width="684" border="0"><tr><td align="left" valign="top" width="228"><a href="ch08_146.htm"><img src="../gifs/txtpreva.gif" alt="Previous" border="0" /></a></td><td align="center" valign="top" width="228"><a href="index.htm"><img src="../gifs/txthome.gif" alt="Home" border="0" /></a></td><td align="right" valign="top" width="228"><a href="ch08_148.htm"><img src="../gifs/txtnexta.gif" alt="Next" border="0" /></a></td></tr><tr><td align="left" valign="top" width="228">8.146. Math::Complex</td><td align="center" valign="top" width="228"><a href="index/index.htm"><img src="../gifs/index.gif" alt="Book Index" border="0" /></a></td><td align="right" valign="top" width="228">8.148. MIME::Base64</td></tr></table></div><hr width="684" align="left" /><img src="../gifs/navbar.gif" usemap="#library-map" border="0" alt="Library Navigation Links" /><p><p><font size="-1"><a href="copyrght.htm">Copyright © 2002</a> O'Reilly & Associates. 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