<p>The <strong class="pkg">Kan</strong> package started out as part of Anne Heyworth's thesis <a href="chapBib.html#biBanne-thesis">[Hey99]</a>, and was designed to compute induced actions of categories (see also <a href="chapBib.html#biBBrHe">[BH00]</a>).</p>
<p>This version of <strong class="pkg">Kan</strong> only provides functions for the computation of normal forms of representatives of double cosets of finitely presented groups, and is made available in support of the paper <a href="chapBib.html#biBBrGhHeWe">[BGHW06]</a>. Existing methods for computing double cosets in <strong class="pkg">GAP</strong> are described in <a href="chapBib.html#biBSteveL">[Lin91]</a>.</p>
<p>The package is loaded into <strong class="pkg">GAP</strong> with the command</p>
<p>The package may be obtained as a compressed tar file <code class="file">kan-version.number.tar.gz</code> by ftp from one of the following sites:</p>
</li>
<li><p>any <strong class="pkg">GAP</strong> archive, e.g. <span class="URL"><a href="https://www.gap-system.org/Packages/packages.html">https://www.gap-system.org/Packages/packages.html</a></span>;</p>
</li>
</ul>
<p>The package also has a GitHub repository at: <span class="URL"><a href="https://github.com/gap-packages/kan/">https://github.com/gap-packages/kan/</a></span>.</p>
<p>Some of the functions in the <strong class="pkg">Automata</strong> package are used to compute word acceptors and regular expressions for the languages they accept.</p>
<p>The <strong class="pkg">KBMag</strong> package is also used to compute a word acceptor of a group <code class="code">G</code> when <code class="code">G</code> has no finite rewriting system. If <strong class="pkg">KBMag</strong> is not available (the user is not on a UNIX system, or the C-programs have not been compiled), the file <code class="file">dckbmag.gi</code> will not be read, so methods for the functions detailed in section2.4.1 will not be available.</p>
<p>Once the package is loaded, it is possible to check the installation is correct by running a test file of the manual examples with the following command. (The test file itself is <code class="file">tst/fulltest.tst</code> or <code class="file">tst/parttest.tst</code>, depending whether or not <strong class="pkg">KBMag</strong> is available.)</p>
<div class="example"><pre>
<span class="GAPprompt">gap></span> <span class="GAPinput">ReadPackage( "kan", "tst/testall.g" );</span>
#I Testing /Applications/gap/my-dev/pkg/kan/tst/fulltest.tst
#I No errors detected while testing package kan
true
</pre></div>
<p>The information parameter <code class="code">InfoKan</code> takes default value <code class="code">0</code>. When raised to a higher value, additional information is printed out.</p>
<p>Once the package is loaded, the manual <code class="code">doc/manual.pdf</code> can be found in the documentation folder. The <code class="code">html</code> versions, with or without MathJax, may be rebuilt as follows.</p>
<p>Please send bug reports, suggestions and other comments to the second author, or use the GitHub issue tracker at <span class="URL"><a href="https://github.com/gap-packages/kan/issues/new">https://github.com/gap-packages/kan/issues/new</a></span>.</p>
<p>Additional information can be found on the <em>Computational Higher-dimensional Discrete Algebra</em> website at <span class="URL"><a href="https://github.com/cdwensley">https://github.com/cdwensley</a></span>.</p>
