<p /eadbodyclass=chap2 ="jscontent()"
<p<a ="X823150E97BE77525" name="X823150E97BE77525"></a<pjava.lang.StringIndexOutOfBoundsException: Index 62 out of bounds for length 62
<div class="ChapSects"><a href="chap2.html#X823150E97BE77525">2 <span class="Heading">Extending Gauss Functionalityjava.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0
<div=ContSect">span class="tocline< =nocss>nbsp/spanahrefchap2htmlX84F709227E5EEB55">2. ><span class="tocline"><span class="nocss"> </span><a href="chap2.html#X7F21EDDF81C27747">2.2 <span class="Heading">The applications of the <strong class="pkg">Gauss</strong> package algorithms</span></a>
</span>
</div>
</div>
<h4>2.1 <span class="Heading">The need for extended functionality</span></h4>
<p><strong class="pkg">GAP</strong> has a lot of functionality for row echelon forms of matrices. These can be called by <code class="code">SemiEchelonForm</code> and similar commands. All of these work for the <strong class="pkg">GAP</strong> matrix type over fields. However, these algorithms are not capable of computing a reduced row echelon form (RREF) of a matrix, there is no way to "Gauss upwards". While this is not neccessary for things like Rank or Kernel computations, this was one in a number of< class="ChapSects"><a href="chap2.html#X823150E97BE77525"">2Heading">ExtendingGaussFunctionality/>
p<="X84F709227E5EEB55" ="X84F709227E5EEB55>/>/p>
<p>It< class"GAP/> has lot of unctionalityfor ow echelon matrices. These can be called by SemiEchelonForm and similar commands. All of these work for the GAP matrix type over fields. However, these algorithms are not capable of computing a reduced row echelon form (RREF) of a matrix, there is no way to "Gauss upwards". While
<p>I am proud to tell you that, thanks to optimizing the algorithms for matrices over GF(2), it was possible
<ppIamproud tell that,thanks optimizing algorithms matrices GF,it possibleto the()Rank of matrix above less 20minutes with usage of 3 GB/p>
<h4. <span class="Heading">The of the<trong="pkg"Gauss</strong packagealgorithms/></h4
<p>Please referp> refer <ahref".html#biBhomalg-project>[]<>to outmoreaboutthe">homalgGausspkg>GaussForHomalg</> a =".html#biBGaussForHomalg">[ö]<a , which, as<strong=pkgRingsForHomalg/> < href".html#>BGKL08> doesforexternal Rings, serves astheconnectionbetween< class"">homalg>Gauss/>.By allowing "> to computational to strongclass"">' capabilities andsparsematrices fieldsandrings of / ⟨pn⟩/>./pjava.lang.StringIndexOutOfBoundsException: Index 1016 out of bounds for length 1016
<p>li
<ul>
<li><p>Computing a row basis of a module (<code class="code">BasisOfRowModule</code>).</p>
</li>
<li<> a module a basis < classcode></code)<p>>
</li>In addition these only relativelyeasy tools matrixmanipulation needed from andmultiplication finding zero inamatrix, to the for it behelpful tosupply < class"">homalgstrong>with more procedures<p
<li> therelations between elements< classcode></code>.<p
</li>
</ul
<pIn addition thesetasks relatively toolsfor manipulationareneeded,ranging additionand to thezero in matrix, to theneed communication might helpful supply<strong="pkg>omalg
<the above canbe difficult,for, working noncommutative polynomialrings,in <strong="">Gauss/trongcase they all doneas asyou computea Row Form isclear <codeclass"">asisOfRowModule</> the of the ofthe arealready basis themodule< classfunc"> < class="">42-/></a) used computeRREFsbased thestrong="">GAP/strong> method classcode>SemiEchelonMat</>for EchelonFormsp>
<p>Lets look the second, the functioncodeclass"D<> face of reducingamodule< class"java.lang.StringIndexOutOfBoundsException: Range [163, 162) out of bounds for length 286
<divclasspcenter< classGAPDocTable
<tr>
<td java.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0
<td class="tdcenter">A</td>
</tr>
<
<p>The,< classcode</>, concerned the between ofa , each representing amodule.Overfield relationsare exactly kernel matrixOne can easily see that this can achieved taking matrix<p
<td class="tdcenter">B</java.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0
</tr>
</able<br>
</div>
<Bycomputingthe (notice howimportant span="<> theside single purpose Gaussian into we. Therefore itwaslogical < =func<>(<href.htmlX811A3B547A27A895<java.lang.StringIndexOutOfBoundsException: Range [422, 417) out of bounds for length 523
<p>Note></
<p>The third procedure, <code class="code">SygygiesGeneratorsOfRows</code>, is concerned with the relations between rows of a matrix, each
<div class="pcenter"><table class="GAPDocTable
<tr
<td class="tdcenter">> syzygy < class" / ⟨p^n⟩SimpleMathv (..0h*..,) 0</> existsspan=SimpleMathg≠>such < class=SimpleMathg h </>, thevectorspan="SimpleMath"> ⋅</span as an additionalrow which to reduced can reducedwith After morework for < ="func"KernelMat/>(a=".#java.lang.StringIndexOutOfBoundsException: Range [606, 605) out of bounds for length 713
<td class="tdcenter">Id</td>
</tr>
</table><br />
</div>
<p>and computing its
<p>Approaching this problem led to the method <code class="func">EchelonMatTransformation</java.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0
<p>As you can see, the development of hermite algorithms was not continued for dense matrices. There are two reasons for that: <strong class="pkg">GAP</strong> already has very good algorithms for ℤ, and for small matrices the disadvantage of computing over ℤ, potentially leading to coefficient explosion, is marginal.</p>
Die Informationen auf dieser Webseite wurden
nach bestem Wissen sorgfältig zusammengestellt. Es wird jedoch weder Vollständigkeit, noch Richtigkeit,
noch Qualität der bereit gestellten Informationen zugesichert.
Bemerkung:
Die farbliche Syntaxdarstellung ist noch experimentell.