[petsc-users] Solve for all repeated eigenvalues

[Greg Meyer]

Hi all,

I'm using SLEPc to solve for some eigenvalues. If I ask for the eigenvalues
with the leftmost real part (using SMALLEST_REAL), and there are repeated
eigenvalues, it appears that the solver does not always find all of the
repeated values before jumping up to the next unique eigenvalue. For
example if the lowest eigenvalues of my matrix are [-12, -10, -10, -10,
-8], and I request 4 eigenvalues, I may get [-12, -10, -10, -8]. I'm using
the default solver. Is there any way, or any solver, that ensures that no
eigenvalues are skipped?

Thanks in advance,
Greg
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