dolfin team mailing list archive

["Garth N. Wells" <gnw20@xxxxxxxxx>]

Kent-Andre Mardal wrote:
> BTW: the Assembler code that computes A, b and enforces BC
> simultaneously in a symmetric way, 

Very nice. We can now implement some symmetric linear solvers.

Do you keep the 'Dirichlet' dofs and zero the row and column, or do you 
eliminate them from the global system?

is now faster than the standard
> non-symmetric way of doing it: 
>
> timings:
> new     : 1.55
> standard: 1.94 

Which backend is this using? It could be saying more about the 
efficiency of the function ident(..), which I suspect is slow for 
uBlasMatrix, than the assembly process.

Garth

> check demo/pde/sym-dirichlet-bc/speed-up-test.py
>
> Currently only cell integrals and exterior facet integrals are
> implemented. 
>
> Kent
>
> On on., 2008-08-13 at 11:46 +0200, DOLFIN wrote:
> > One or more new changesets pushed to the primary dolfin repository.
> > A short summary of the last three changesets is included below.
> >
> > changeset:   4563:3fbd8bd0822d1f363521ccd29afc1f694205ecc5
> > tag:         tip
> > parent:      4562:d912b2383bc98f98be1fa61e25cac3dec72df8fb
> > parent:      4554:b3a0c04c85c2231e87bf187b35bcf6e2e27e8247
> > user:        Kent-Andre Mardal <kent-and@xxxxxxxxx>
> > date:        Wed Aug 13 11:41:52 2008 +0200
> > files:       dolfin/fem/Assembler.cpp dolfin/fem/Assembler.h
> > description:
> > merge
> >
> >
> > changeset:   4562:d912b2383bc98f98be1fa61e25cac3dec72df8fb
> > user:        Kent-Andre Mardal <kent-and@xxxxxxxxx>
> > date:        Wed Aug 13 11:41:23 2008 +0200
> > files:       demo/pde/sym-dirichlet-bc/demo.py demo/pde/sym-dirichlet-bc/speed-up-test.py
> > description:
> > update text
> >
> >
> > changeset:   4561:4749e1c883b9e21767a2c1142541badb6461866c
> > parent:      4560:5daf9606ed74d52cb52ccf4e2f3cf20ab7152277
> > parent:      4549:463016a27aadf2d3994d2249b4059feaf264dd5d
> > user:        Kent-Andre Mardal <kent-and@xxxxxxxxx>
> > date:        Wed Aug 13 11:34:33 2008 +0200
> > files:       dolfin/fem/Assembler.cpp dolfin/la/MTL4SparsityPattern.cpp dolfin/la/MTL4SparsityPattern.h dolfin/mesh/ALE.cpp dolfin/mesh/ALE.h dolfin/mesh/ALEType.h dolfin/swig/dolfin_headers.i
> > description:
> > merge
> >
> > ----------------------------------------------------------------------
> > For more details, visit http://www.fenics.org/hg/dolfin
> > _______________________________________________
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> > DOLFIN-dev@xxxxxxxxxx
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>
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