<?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>inducedMap(Module,Module) -- compute the map induced by the identity</title> <link rel="stylesheet" type="text/css" href="../../../../Macaulay2/Style/doc.css"/> </head> <body> <table class="buttons"> <tr> <td><div><a href="_induced__Map_lp__Module_cm__Module_cm__Matrix_rp.html">next</a> | <a href="_induced__Map_lp..._cm_sp__Verify_sp_eq_gt_sp..._rp.html">previous</a> | <a href="_induced__Map_lp__Module_cm__Module_cm__Matrix_rp.html">forward</a> | <a href="_induced__Map_lp..._cm_sp__Verify_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>inducedMap(Module,Module) -- compute the map induced by the identity</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>inducedMap(M,N)</tt></div> </dd></dl> </div> </li> <li><span>Function: <a href="_induced__Map.html" title="compute an induced map">inducedMap</a></span></li> <li><div class="single">Inputs:<ul><li><span><tt>M</tt>, <span>a <a href="___Module.html">module</a></span></span></li> <li><span><tt>N</tt>, <span>a <a href="___Module.html">module</a></span></span></li> </ul> </div> </li> <li><div class="single">Outputs:<ul><li><span><span>a <a href="___Matrix.html">matrix</a></span>, the homomorphism <tt>M <-- N</tt> induced by the identity.</span></li> </ul> </div> </li> <li><div class="single"><a href="_using_spfunctions_spwith_spoptional_spinputs.html">Optional inputs</a>:<ul><li><span><a href="_induced__Map_lp..._cm_sp__Degree_sp_eq_gt_sp..._rp.html">Degree => ...</a>, -- specify the degree of a map</span></li> <li><span><a href="_induced__Map_lp..._cm_sp__Verify_sp_eq_gt_sp..._rp.html">Verify => ...</a>, </span></li> </ul> </div> </li> </ul> </div> <div class="single"><h2>Description</h2> <div>The modules <tt>M</tt> and <tt>N</tt> must both be <a href="_subquotient_spmodules.html" title="the way Macaulay2 represents modules">subquotient modules</a> of the same ambient free module <tt>F</tt>. If <tt>M = M1/M2</tt> and <tt>N = N1/N2</tt>, where <tt>M1</tt>, <tt>M2</tt>, <tt>N1</tt>, <tt>N2</tt> are all submodules of <tt>F</tt>, then return the map induced by <tt>F --> F</tt>. If the optional argument <tt>Verify</tt> is given, check that the result defines a well defined homomorphism.<p/> In this example, we make the inclusion map between two submodules of <tt>R^3</tt>. M is defined by two elements and N is generated by one element in M<table class="examples"><tr><td><pre>i1 : R = ZZ/32003[x,y,z];</pre> </td></tr> <tr><td><pre>i2 : P = R^3;</pre> </td></tr> <tr><td><pre>i3 : M = image(x*P_{1}+y*P_{2} | z*P_{0}) o3 = image | 0 z | | x 0 | | y 0 | 3 o3 : R-module, submodule of R</pre> </td></tr> <tr><td><pre>i4 : N = image(x^4*P_{1} + x^3*y*P_{2} + x*y*z*P_{0}) o4 = image | xyz | | x4 | | x3y | 3 o4 : R-module, submodule of R</pre> </td></tr> <tr><td><pre>i5 : h = inducedMap(M,N) o5 = {1} | x3 | {1} | xy | o5 : Matrix</pre> </td></tr> <tr><td><pre>i6 : source h == N o6 = true</pre> </td></tr> <tr><td><pre>i7 : target h == M o7 = true</pre> </td></tr> <tr><td><pre>i8 : ambient M == ambient N o8 = true</pre> </td></tr> </table> </div> </div> <div class="single"><h2>See also</h2> <ul><li><span><a href="_induces__Well__Defined__Map.html" title="whether a map is well defined">inducesWellDefinedMap</a> -- whether a map is well defined</span></li> <li><span><a href="_subquotient.html" title="make a subquotient module">subquotient</a> -- make a subquotient module</span></li> </ul> </div> </div> </body> </html>