KSPBuildResidual in ex42.c
In src/ksp/ksp/examples/tutorials/ex42.c.html the Stokes system is solved and KSPBuildResidual is used to compute the residuals for the velocity components and pressure individually. Are these the preconditioned residuals or the true residuals? And how to get both? dr. ir. Christiaan Klaij CFD Researcher Research & Development E mailto:[email protected] T +31 317 49 33 44 MARIN 2, Haagsteeg, P.O. Box 28, 6700 AA Wageningen, The Netherlands T +31 317 49 39 11, F +31 317 49 32 45, I www.marin.nl
On Tue, May 22, 2012 at 6:10 AM, Klaij, Christiaan <[email protected]> wrote:
In src/ksp/ksp/examples/tutorials/ex42.c.html the Stokes system is solved and KSPBuildResidual is used to compute the residuals for the velocity components and pressure individually. Are these the preconditioned residuals or the true residuals?
The true residual.
And how to get both?
Precondition it. Note that if you only want norms, GMRES will compute one (preconditioned by default).
participants (2)
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Jed Brown -
Klaij, Christiaan