dolfin team mailing list archive

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

On 2 September 2012 11:20, Anders Logg <logg@xxxxxxxxx> wrote:
> On Sat, Sep 01, 2012 at 01:33:38PM +0100, Garth N. Wells wrote:
>> Can someone remind me why we have the two classes SymmetricAssembler
>> and SystemAssembler instead of just one?
>
> SymmetricAssembler adds some extra functionality not provided by
> SystemAssembler (symmetric modification of RSH vector), but I suspect
> it does so at an extra cost, which is why SymmetricAssembler is still
> there.
>
> I used to think it is a problem to have multiple assemblers, but I'm
> not so worried about it now.
>

It's a problem if a bug pops up (like we have now) that 4 versions
need to be fixed.

The purpose of Assembler OpenMPAssembler are clear, but it's not clear
why we have both SymmetricAssembler and SystemAssembler. The extra
functionality is limited and could easily go into SystemAssembler.

Garth

> But even if we have multiple assemblers, it is important that we have
> one really good standard default assembler that tries to provide all
> functionality of the "special-purpose" assemblers, as long as it can
> do so without overhead.
>
> --
> Anders