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<html><head><title>Mathematics (Learning Perl, 3rd Edition)</title><link rel="stylesheet" type="text/css" href="../style/style1.css" /><meta name="DC.Creator" content="Randal L. Schwartz and Tom Phoenix" /><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="0596001320L" /><meta name="DC.Subject.Keyword" content="stuff" /><meta name="DC.Title" content="Learning Perl, 3rd Edition" /><meta name="DC.Type" content="Text.Monograph" /></head><body bgcolor="#ffffff"><img alt="Book Home" border="0" src="gifs/smbanner.gif" usemap="#banner-map" /><map name="banner-map"><area shape="rect" coords="1,-2,616,66" href="index.htm" alt="Learning Perl, 3rd Edition" /><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="appb_08.htm"><img alt="Previous" border="0" src="../gifs/txtpreva.gif" /></a></td><td align="center" valign="top" width="228"><a href="index.htm"></a></td><td align="right" valign="top" width="228"><a href="appb_10.htm"><img alt="Next" border="0" src="../gifs/txtnexta.gif" /></a></td></tr></table></div><h2 class="sect1">B.9. Mathematics</h2><p>Perl can do just about any kind of<a name="INDEX-1223" />mathematics youcan dream up.</p><a name="lperl3-APP-B-SECT-9.1" /><div class="sect2"><h3 class="sect2">B.9.1. Advanced Math Functions</h3><p>All of the basic <a name="INDEX-1224" />mathematical functions(<a name="INDEX-1225" />square root,<a name="INDEX-1226" />cosine,<a name="INDEX-1227" />logarithm,<a name="INDEX-1228" />absolutevalue, and many others) are available as <a name="INDEX-1229" />built in functions; see the<em class="emphasis">perlfunc</em><a name="INDEX-1230" /> manpage for details. Some others (liketangent or base-10 logarithm) are omitted, but those may be easilycreated from the basic ones, or loaded from a simple module that doesso. (See the <tt class="literal">POSIX</tt><a name="INDEX-1231" />module for many common math functions.)</p></div><a name="lperl3-APP-B-SECT-9.2" /><div class="sect2"><h3 class="sect2">B.9.2. Imaginary and Complex Numbers</h3><p>Although the core of Perl doesn't directly support them, thereare modules available for working with<a name="INDEX-1232" /> <a name="INDEX-1233" /> <a name="INDEX-1234" />complex numbers. These overload thenormal operators and functions, so that you can still multiply with<tt class="literal">*</tt> and get a square root with<tt class="literal">sqrt</tt>, even when using complex numbers. See the<tt class="literal">Math::Complex</tt><a name="INDEX-1235" /> module.</p></div><a name="lperl3-APP-B-SECT-9.3" /><div class="sect2"><h3 class="sect2">B.9.3. Large and High-Precision Numbers</h3><p>You can do math with arbitrarily large<a name="INDEX-1236" /><a name="INDEX-1237" /><a name="INDEX-1238" />numbers with an arbitrary number ofdigits of accuracy. For example, you could calculate the factorial oftwo thousand, or determine <img align="absmiddle" src="figs/U03C0.gif" /> to ten-thousand digits. See the<tt class="literal">Math::BigInt</tt><a name="INDEX-1239" /> and<tt class="literal">Math::BigFloat</tt><a name="INDEX-1240" /> modules.</p></div><hr width="684" align="left" /><div class="navbar"><table width="684" border="0"><tr><td align="left" valign="top" width="228"><a href="appb_08.htm"><img alt="Previous" border="0" src="../gifs/txtpreva.gif" /></a></td><td align="center" valign="top" width="228"><a href="index.htm"><img alt="Home" border="0" src="../gifs/txthome.gif" /></a></td><td align="right" valign="top" width="228"><a href="appb_10.htm"><img alt="Next" border="0" src="../gifs/txtnexta.gif" /></a></td></tr><tr><td align="left" valign="top" width="228">B.8. Other Operators and Functions</td><td align="center" valign="top" width="228"><a href="index/index.htm"><img alt="Book Index" border="0" src="../gifs/index.gif" /></a></td><td align="right" valign="top" width="228">B.10. Lists and Arrays</td></tr></table></div><hr width="684" align="left" /><img alt="Library Navigation Links" border="0" src="../gifs/navbar.gif" usemap="#library-map" /><p><p><font size="-1"><a href="copyrght.htm">Copyright © 2002</a> O'Reilly & Associates. All rights reserved.</font></p><map name="library-map"><area shape="rect" coords="1,0,85,94" href="../index.htm"><area shape="rect" coords="86,1,178,103" href="../lwp/index.htm"><area shape="rect" coords="180,0,265,103" href="../lperl/index.htm"><area shape="rect" coords="267,0,353,105" href="../perlnut/index.htm"><area shape="rect" coords="354,1,446,115" href="../prog/index.htm"><area shape="rect" coords="448,0,526,132" href="../tk/index.htm"><area shape="rect" coords="528,1,615,119" href="../cookbook/index.htm"><area shape="rect" coords="617,0,690,135" href="../pxml/index.htm"></map></body></html>⌨️ 快捷键说明
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