[petsc-users] Solving Poisson equation with multigrid

[Jed Brown]

Michele Rosso <mrosso at uci.edu> writes:

>>     With petsc-3.4 (which you should upgrade to), use
>>     -mg_coarse_sub_pc_factor_shift_type NONZERO

Actually, use this with petsc-3.3 also (and please upgrade to
petsc-3.4).

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