[petsc-users] QCG and KSPSetPCSide

[Carol.Brickley at awe.co.uk]

All,

I am trying to use KSPSolve for a QCG solver using petsc 3.4.3 and it gives me the error of "PC does not have left symmetric apply!". Further reading on the web pages suggest I need to use KSPSetPCSide to set up a symmetric side for the solver. However, this does not seem to work. I am doing the following in an F90 code:

call KSPSetPCType(ksp_ptr%ksp, 'qcg', petsc_err)
call KSPSetPCSide(ksp_ptr%ksp, PC_SYMMETRIC, petsc_err)

but I still get the same failure message when I call KSPSolve(ksp_ptr%ksp..)  later on.

Any ideas as to why this is not working?

Carol





Dr Carol Brickley
BSc,PhD,ARCS,DIC,MBCS

Senior Software Engineer
Applied Computer Science
DS+T,
AWE
Aldermaston
Reading
Berkshire
RG7 4PR

Direct: 0118 9855035



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