dolfin team mailing list archive

[Johan Jansson <johanjan@xxxxxxxxxxxxxxxx>]

On Fri, Mar 31, 2006 at 01:50:13PM +0200, Garth N. Wells wrote:

...

> > For a full 6x6 matrix which is assembled 1e7 times, the normalised
> > timings were
> > 
> > PETSc*:                   25
> > Boost multi_array class:  8
> > Boost ublas::matrix:      1.7
> > std::vector based matrix: 4.8
> > standard array:           1
> > 
> 
> Small correction:
> Blitz++: 1.7
> ublas:   1.95
> 
> ublas (http://www.boost.org/libs/numeric/ublas/doc/index.htm) looks
> really nice and provides everything I would like to have for a dense
> matrix. It's a template library, we don't have to worry about linking to
> it. If we use it, we could avoid a dependency by including the header
> files in DOLFIN somewhere, something like dolfin/contrib?
> 
> Garth
> 

I evaluated ublas when we were looking at different sparse linear
algebra packages. I also liked the design of ublas, but the sparse
performance was quite poor. But if we only use the dense
representation I guess it would be a great candidate.

A dense linear algebra representation could perhaps also be used for
the affine geometry mapping, which is currently implemented without
abstractions. If there's no significant performance penalty that is.

  Johan