Hello all,

I am trying to use ex7 to solve series of generalized problem. The running
commands are:

./ex7 -f1 petsc_stiff19.dat -f2 petsc_mass19.dat -mat_type sbaij
-eps_gen_hermitian -eps_type krylovschur -*eps_smallest_magnitude*.
-eps_monitor_conv -st_k    sp_type bcgs -st_pc_type bjacobi -st_sub_pc_type
icc -st_ksp_rtol 1.e-4 -eps_tol 1.e-4 -eps_nev 40 -st_type sinvert

It works fine, but when my problem contains zero eigenvalue, it fails to
converge.

Supposedly, I should use *eps_target -0.1* instead of
*eps_smallest_magnitude*. However if eps_target is used, I run into
a memory issue:

PETSC ERROR: --------------------- Error Message
------------------------------------
PETSC ERROR: Argument out of range!
PETSC ERROR: New nonzero at (0,6) caused a malloc!
PETSC ERROR:
------------------------------------------------------------------------

Does anybody know how to solve this? Thanks!

Jifeng Zhao
PhD candidate at Northwestern University, US
Theoretical and Applied Mechanics Program

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