<?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>SheafOfRings -- the class of sheaves of rings</title> <link rel="stylesheet" type="text/css" href="../../../../Macaulay2/Style/doc.css"/> </head> <body> <table class="buttons"> <tr> <td><div><a href="___Sheaf__Of__Rings_sp^_sp__List.html">next</a> | <a href="_sheaf__Hom_lp__Coherent__Sheaf_cm__Coherent__Sheaf_rp.html">previous</a> | <a href="___Sheaf__Of__Rings_sp^_sp__List.html">forward</a> | <a href="_sheaf__Hom_lp__Coherent__Sheaf_cm__Coherent__Sheaf_rp.html">backward</a> | up | <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> <hr/> <div><h1>SheafOfRings -- the class of sheaves of rings</h1> <div class="single"><h2>Description</h2> <div><table class="examples"><tr><td><pre>i1 : X = Proj(QQ[x..z]) o1 = X o1 : ProjectiveVariety</pre> </td></tr> <tr><td><pre>i2 : OO_X o2 = OO X o2 : SheafOfRings</pre> </td></tr> <tr><td><pre>i3 : OO_X^6 6 o3 = OO X o3 : coherent sheaf on X, free</pre> </td></tr> </table> </div> </div> <div class="single"><h2>See also</h2> <ul><li><span><a href="___Variety.html" title="the class of all algebraic varieties">Variety</a> -- the class of all algebraic varieties</span></li> <li><span><a href="___O__O_sp_us_sp__Variety.html" title="the structure sheaf">OO</a> -- the structure sheaf</span></li> </ul> </div> <div class="waystouse"><h2>Functions and methods returning a sheaf of rings :</h2> <ul><li><span>Ring ~, see <span><a href="_sheaf_lp__Ring_rp.html" title="make a coherent sheaf of rings">sheaf(Ring)</a> -- make a coherent sheaf of rings</span></span></li> <li><span><a href="_sheaf_lp__Ring_rp.html" title="make a coherent sheaf of rings">sheaf(Ring)</a> -- make a coherent sheaf of rings</span></li> <li><span><a href="_sheaf_lp__Variety_cm__Ring_rp.html" title="make a coherent sheaf of rings">sheaf(Variety,Ring)</a> -- make a coherent sheaf of rings</span></li> </ul> <h2>Methods that use a sheaf of rings :</h2> <ul><li><span>SheafOfRings (*), see <span><a href="___Coherent__Sheaf_sp_lp_st_rp.html" title="sum of twists">CoherentSheaf (*)</a> -- sum of twists</span></span></li> <li><span>SheafOfRings ^ ZZ, see <span><a href="___Coherent__Sheaf_sp^_sp__Z__Z.html" title="direct sum">CoherentSheaf ^ ZZ</a> -- direct sum</span></span></li> <li><span>SheafOfRings ZZ, see <span><a href="___Coherent__Sheaf_sp__Z__Z.html" title="canonical twist of a coherent sheaf">CoherentSheaf ZZ</a> -- canonical twist of a coherent sheaf</span></span></li> <li><span>Ext^ZZ(CoherentSheaf,SheafOfRings), see <span><a href="___Ext^__Z__Z_lp__Coherent__Sheaf_cm__Coherent__Sheaf_rp.html" title="global Ext">Ext^ZZ(CoherentSheaf,CoherentSheaf)</a> -- global Ext</span></span></li> <li><span>Ext^ZZ(SheafOfRings,CoherentSheaf), see <span><a href="___Ext^__Z__Z_lp__Coherent__Sheaf_cm__Coherent__Sheaf_rp.html" title="global Ext">Ext^ZZ(CoherentSheaf,CoherentSheaf)</a> -- global Ext</span></span></li> <li><span>Ext^ZZ(SheafOfRings,SheafOfRings), see <span><a href="___Ext^__Z__Z_lp__Coherent__Sheaf_cm__Coherent__Sheaf_rp.html" title="global Ext">Ext^ZZ(CoherentSheaf,CoherentSheaf)</a> -- global Ext</span></span></li> <li><span>Ext^ZZ(SheafOfRings,SumOfTwists), see <span><a href="___Ext^__Z__Z_lp__Coherent__Sheaf_cm__Sum__Of__Twists_rp.html" title="global Ext">Ext^ZZ(CoherentSheaf,SumOfTwists)</a> -- global Ext</span></span></li> <li><span><a href="___H__H^__Z__Z_sp__Sheaf__Of__Rings.html" title="cohomology of a sheaf of rings on a projective variety">HH^ZZ SheafOfRings</a> -- cohomology of a sheaf of rings on a projective variety</span></li> <li><span>Hom(CoherentSheaf,SheafOfRings), see <span><a href="___Hom_lp__Coherent__Sheaf_cm__Coherent__Sheaf_rp.html" title="global Hom">Hom(CoherentSheaf,CoherentSheaf)</a> -- global Hom</span></span></li> <li><span>Hom(SheafOfRings,CoherentSheaf), see <span><a href="___Hom_lp__Coherent__Sheaf_cm__Coherent__Sheaf_rp.html" title="global Hom">Hom(CoherentSheaf,CoherentSheaf)</a> -- global Hom</span></span></li> <li><span>Hom(SheafOfRings,SheafOfRings), see <span><a href="___Hom_lp__Coherent__Sheaf_cm__Coherent__Sheaf_rp.html" title="global Hom">Hom(CoherentSheaf,CoherentSheaf)</a> -- global Hom</span></span></li> <li><span>SheafOfRings LowerBound, see <span><a href="___Lower__Bound.html" title="the class of lower bound objects">LowerBound</a> -- the class of lower bound objects</span></span></li> <li><span><a href="_module_lp__Sheaf__Of__Rings_rp.html" title="make or get a module">module(SheafOfRings)</a> -- make or get a module</span></li> <li><span>ring(SheafOfRings), see <span><a href="_ring.html" title="get the associated ring of an object">ring</a> -- get the associated ring of an object</span></span></li> <li><span>sheafExt^ZZ(CoherentSheaf,SheafOfRings), see <span><a href="_sheaf__Ext^__Z__Z_lp__Coherent__Sheaf_cm__Coherent__Sheaf_rp.html" title="sheaf Ext of coherent sheaves">sheafExt^ZZ(CoherentSheaf,CoherentSheaf)</a> -- sheaf Ext of coherent sheaves</span></span></li> <li><span>sheafExt^ZZ(SheafOfRings,CoherentSheaf), see <span><a href="_sheaf__Ext^__Z__Z_lp__Coherent__Sheaf_cm__Coherent__Sheaf_rp.html" title="sheaf Ext of coherent sheaves">sheafExt^ZZ(CoherentSheaf,CoherentSheaf)</a> -- sheaf Ext of coherent sheaves</span></span></li> <li><span>sheafExt^ZZ(SheafOfRings,SheafOfRings), see <span><a href="_sheaf__Ext^__Z__Z_lp__Coherent__Sheaf_cm__Coherent__Sheaf_rp.html" title="sheaf Ext of coherent sheaves">sheafExt^ZZ(CoherentSheaf,CoherentSheaf)</a> -- sheaf Ext of coherent sheaves</span></span></li> <li><span>sheafHom(CoherentSheaf,SheafOfRings), see <span><a href="_sheaf__Hom_lp__Coherent__Sheaf_cm__Coherent__Sheaf_rp.html" title="sheaf Hom">sheafHom(CoherentSheaf,CoherentSheaf)</a> -- sheaf Hom</span></span></li> <li><span>sheafHom(SheafOfRings,CoherentSheaf), see <span><a href="_sheaf__Hom_lp__Coherent__Sheaf_cm__Coherent__Sheaf_rp.html" title="sheaf Hom">sheafHom(CoherentSheaf,CoherentSheaf)</a> -- sheaf Hom</span></span></li> <li><span>sheafHom(SheafOfRings,SheafOfRings), see <span><a href="_sheaf__Hom_lp__Coherent__Sheaf_cm__Coherent__Sheaf_rp.html" title="sheaf Hom">sheafHom(CoherentSheaf,CoherentSheaf)</a> -- sheaf Hom</span></span></li> <li><span><a href="___Sheaf__Of__Rings_sp^_sp__List.html" title="make a graded free coherent sheaf">SheafOfRings ^ List</a> -- make a graded free coherent sheaf</span></li> <li><span><a href="_variety_lp__Sheaf__Of__Rings_rp.html" title="get the variety">variety(SheafOfRings)</a> -- get the variety</span></li> </ul> </div> <div class="waystouse"><h2>For the programmer</h2> <p>The object <a href="___Sheaf__Of__Rings.html" title="the class of sheaves of rings">SheafOfRings</a> is <span>a <a href="___Type.html">type</a></span>, with ancestor classes <a href="___Hash__Table.html" title="the class of all hash tables">HashTable</a> < <a href="___Thing.html" title="the class of all things">Thing</a>.</p> </div> </div> </body> </html>