<?xml version="1.0" encoding="utf-8" ?> <!-- for emacs: -*- coding: utf-8 -*- --> <!-- Apache may like this line in the file .htaccess: AddCharset utf-8 .html --> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1 plus MathML 2.0 plus SVG 1.1//EN" "http://www.w3.org/2002/04/xhtml-math-svg/xhtml-math-svg-flat.dtd" > <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en"> <head><title>GroupRevLex</title> <link rel="stylesheet" type="text/css" href="../../../../Macaulay2/Style/doc.css"/> </head> <body> <table class="buttons"> <tr> <td><div><a href="_definition_spof_spproduct_sp_lpblock_rp_sporders.html">next</a> | <a href="___Group__Lex.html">previous</a> | <a href="_definition_spof_spproduct_sp_lpblock_rp_sporders.html">forward</a> | <a href="___Group__Lex.html">backward</a> | <a href="_monomial_sporderings.html">up</a> | <a href="index.html">top</a> | <a href="master.html">index</a> | <a href="toc.html">toc</a> | <a href="http://www.math.uiuc.edu/Macaulay2/">Macaulay2 web site</a></div> </td> </tr> </table> <div><a href="index.html" title="">Macaulay2Doc</a> > <a href="_rings.html" title="">rings</a> > <a href="_monomial_sporderings.html" title="">monomial orderings</a> > <a href="___Group__Rev__Lex.html" title="">GroupRevLex</a></div> <hr/> <div><h1>GroupRevLex</h1> <div class="single"><h2>Description</h2> <div><tt>MonomialOrder => GroupRevLex => n</tt> inverts the first <tt>n</tt> variables in the polynomial ring. In the following example, <tt>a^-1</tt> is in the ring, but <tt>c^-1</tt> is not.<table class="examples"><tr><td><pre>i1 : R = QQ[a..d, MonomialOrder=>GroupRevLex=>2, Global=>false];</pre> </td></tr> <tr><td><pre>i2 : a^-1 -1 o2 = a o2 : R</pre> </td></tr> <tr><td><pre>i3 : try c^(-1) else "failed" o3 = failed</pre> </td></tr> </table> </div> </div> <div class="single"><h2>Caveat</h2> <div>This feature has not been implemented yet.</div> </div> <div class="waystouse"><h2>For the programmer</h2> <p>The object <a href="___Group__Rev__Lex.html" title="">GroupRevLex</a> is <span>a <a href="___Symbol.html">symbol</a></span>.</p> </div> </div> </body> </html>