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<p class="MsoNormal"><span lang="ES">Package: libarmadillo10 <o:p></o:p></span></p>
<p class="MsoNormal"><span lang="ES">Version: 1:10.1.2+dfsg-6+b1<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="ES"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">After updating to Debian 11, the armadillo library for C++ doesn’t work properly anymore (e.g. matrix inversions deliver obviously wrong results), as can be seen in the example code and results attached.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Short note about the problem: Assume you have a square matrix B, then B*inv(B) should yield the unit matrix. In armadillo this worked without problems until the update to Debian 11. Now I get a completely random result
for B*inv(B). The larger the dimension of B the more severe the problem is. There might be a numerical issue that didn’t exist in older Debian versions.<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">According to the Armadillo-team, this is not a problem of Armadillo itself but might be the problem of the versions of libopenblas, liblapack or libblas used by Debian 11.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">One of these libraries might be corrupt or incompatible with Debian 11.<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" style="font-family:Consolas;color:#4472C4">Operating System: Debian GNU/Linux 11 (bullseye)<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:Consolas;color:#4472C4">Kernel: Linux 5.10.0-14-amd64<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:Consolas;color:#4472C4"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-family:Consolas;color:#4472C4">Library Version Description<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:Consolas;color:#4472C4">------------------------------------------------------------------------------------------------------------------------------------------------------<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:Consolas;color:#4472C4">libarmadillo10 1:10.1.2+dfsg-6+b1 streamlined C++ linear algebra library<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:Consolas;color:#4472C4">libblas3:amd64 3.9.0-3 Basic Linear Algebra Reference implementations, shared library<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:Consolas;color:#4472C4">liblapack3:amd64 3.9.0-3 Library of linear algebra routines 3 - shared version<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-family:Consolas;color:#4472C4">libopenblas0-pthread:amd64 0.3.13+ds-3 Optimized BLAS (linear algebra) library (shared lib, pthread)</span><span lang="EN-US" style="font-family:Consolas"><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">Regards<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">Andreas Schlager<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
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