<?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>populateCechComplexCC(Ideal,List) -- Cech complex skeleton for the computation of the characteristic cycles of local cohomology modules</title> <link rel="stylesheet" type="text/css" href="../../../../Macaulay2/Style/doc.css"/> </head> <body> <table class="buttons"> <tr> <td><div><a href="___Pre__Cycles.html">next</a> | <a href="___Poly__Sols_lp..._cm_sp__Alg_sp_eq_gt_sp..._rp.html">previous</a> | <a href="___Pre__Cycles.html">forward</a> | <a href="___Poly__Sols_lp..._cm_sp__Alg_sp_eq_gt_sp..._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>populateCechComplexCC(Ideal,List) -- Cech complex skeleton for the computation of the characteristic cycles of local cohomology modules</h1> <div class="single"><h2>Synopsis</h2> <ul><li><div class="list"><dl class="element"><dt class="heading">Usage: </dt><dd class="value"><div><tt>populateCechComplexCC(I,cc)</tt></div> </dd></dl> </div> </li> <li><span>Function: <a href="_populate__Cech__Complex__C__C_lp__Ideal_cm__List_rp.html" title="Cech complex skeleton for the computation of the characteristic cycles of local cohomology modules">populateCechComplexCC</a></span></li> <li><div class="single">Inputs:<ul><li><span><tt>I</tt>, <span>an <a href="../../Macaulay2Doc/html/___Ideal.html">ideal</a></span>, at which the local cohomology modules H<sup>i</sup><sub>I</sub>(M) are computed.</span></li> <li><span><tt>cc</tt>, <span>a <a href="../../Macaulay2Doc/html/___List.html">list</a></span>, the characteristic cycle of a regular holonomic module M</span></li> </ul> </div> </li> <li><div class="single">Outputs:<ul><li><span><span>a <a href="../../Macaulay2Doc/html/___Mutable__Hash__Table.html">mutable hash table</a></span>, with entries corresponding to the direct summands of the chains in the Cech complex</span></li> </ul> </div> </li> </ul> </div> <div class="single"><h2>Description</h2> <div>For the ideal I=(f<sub>1</sub>,...,f<sub>k</sub>) the routine computes the characteristic cycles of the localized modules M<sub>f<sub>i<sub>1</sub></sub>,...,f<sub>i<sub>k</sub></sub></sub> and places them in the corresponding places in the Cech complex.<table class="examples"><tr><td><pre>i1 : W = QQ[x_1..x_6, a_1..a_6];</pre> </td></tr> <tr><td><pre>i2 : I = minors(2, matrix{{x_1, x_2, x_3}, {x_4, 0, 0}}); o2 : Ideal of W</pre> </td></tr> <tr><td><pre>i3 : cc = {ideal W => 1};</pre> </td></tr> </table> </div> </div> <div class="single"><h2>Caveat</h2> <div>The module has to be a regular holonomic complex-analytic module; while the holomicity can be checked by <a href="_is__Holonomic.html" title="determines whether a D-module (or ideal in Weyl algebra) is holonomic">isHolonomic</a> there is no algorithm to check the regularity.</div> </div> <div class="single"><h2>See also</h2> <ul><li><span><a href="___B__M__M.html" title="the characteristic cycle of the localized $D$-module">BMM</a> -- the characteristic cycle of the localized $D$-module</span></li> <li><span><a href="_prune__Cech__Complex__C__C_lp__Mutable__Hash__Table_rp.html" title="reduction of the Cech complex that produces characteristic cycles of local cohomology modules">pruneCechComplexCC</a> -- reduction of the Cech complex that produces characteristic cycles of local cohomology modules</span></li> </ul> </div> </div> </body> </html>