Hello,

I need to find the spectrum of the a large linear system (over 100,000 
unknowns). Option -ksp_compute_eigenvalues_explicitly ran out of memory since 
the matrix is too big, then -ksp_compute_eigenvalues only gave a small number 
of eigenvalues (around 30). My questions are:

1. Is the number of computed eigenvalues determined by the number of GMRES 
iterations to converge?
2. Can PETSc give the extreme eigenvalues now that the number of computed 
eigenvalues is limited?

Thanks a lot for your info,
Qin   

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