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Hi everyone,
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<div class="">I am diagonalising a large symmetric real matrix for its null space (highly degenerate eigenstates with zero eigenvalues). I am using <span style="font-family: Menlo; font-size: 11px;" class="">krylovschur which is variational, which is supposed
to start with a set of random initial vectors. They will eventually converge to random vectors in the null space.</span></div>
<div class=""><span style="font-family: Menlo; font-size: 11px;" class=""><br class="">
</span></div>
<div class=""><font face="Menlo" class=""><span style="font-size: 11px;" class="">The problem is that if I run the EPSSOLVE with the same set of parameters (e.g. -eps_ncv and -eps_mpd), I always get the same eigenstates in the null space. This implies that
the solver always start the same set of initial “random” vectors. </span></font></div>
<div class=""><font face="Menlo" class=""><span style="font-size: 11px;" class=""><br class="">
</span></font></div>
<div class=""><font face="Menlo" class=""><span style="font-size: 11px;" class="">How does petsc generate the initial random vectors for krylovschur? Is there a way for me to generate different random initial vectors every time I run the diagonalisation (of
the same matrix)?</span></font></div>
<div class=""><font face="Menlo" class=""><span style="font-size: 11px;" class=""><br class="">
</span></font></div>
<div class=""><font face="Menlo" class=""><span style="font-size: 11px;" class="">Thanks, and stay safe and healthy!</span></font></div>
<div class=""><font face="Menlo" class=""><span style="font-size: 11px;" class=""><br class="">
</span></font></div>
<div class=""><font face="Menlo" class=""><span style="font-size: 11px;" class="">Cheers,</span></font></div>
<div class=""><font face="Menlo" class=""><span style="font-size: 11px;" class=""><br class="">
</span></font></div>
<div class=""><font face="Menlo" class=""><span style="font-size: 11px;" class="">Yang Bo</span></font></div>
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