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<p class="MsoNormal">Hi<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span lang="EN-US">I am currently solving linear systems of equations in the form<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">A x = b,<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">with a preconditioned iterative method in Dune. I would also like to solve linear systems with the same system matrix but transposed<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">A^T x = b.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">As far as I can see, the iterative methods and preconditioners in Dune ISTL don’t have an option to do so, and
<a href="http://lists.dune-project.org/pipermail/dune/2015-August/013856.html">I have read</a> that there isn’t an option to directly transpose a matrix (which is also not exactly what I want).<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">The matrix, A, is of the type BCRSMatrix<FieldMatrix<double, 3, 3>>.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">What is the easiest way to solve such a system in Dune?<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Kind regards<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Tobias Ritschel<o:p></o:p></span></p>
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