[petsc-users] Bug when multipling a SBAIJ matrix with a vector

[Andreas Hauffe]

Am Donnerstag 21 Oktober 2010, 14:24:59 schrieb Jed Brown:
> The SBAIJ implementation requires that the diagonal entry exists.  If you
> only have a few rows of all zeros, then just place explicit zeros there,
> otherwise use AIJ or BAIJ both of which work fine with completely empty
> rows (if your system is so sparse that you don't want to store one
> explicit zero per row, then the non-symmetric storage will probably also
> be faster.
> 
> Aren't you getting an error in MatMult_SeqSBAIJ_1?  This is a horrible
> error message, but it comes from trying to log a negative number of flops.
>  I'll put a check into petsc-dev so it gives a better error message.
> 
> Jed

I get no error and this example delivers the right result for PETSC 3.0. What 
did change from 3.0 to 3.1?

So I will but 0 to the diagonal.

best regards,
-- 
Andreas Hauffe

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Technische Universität Dresden
Institut für Luft- und Raumfahrttechnik / Institute of Aerospace Engineering
Lehrstuhl für Luftfahrzeugtechnik / Chair of Aircraft Engineering

D-01062 Dresden
Germany

phone   : (++49)351 463 38496
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mail    : andreas.hauffe at tu-dresden.de
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