dolfin team mailing list archive

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

On Thu, Nov 15, 2012 at 6:37 AM, Martin Sandve Alnæs <martinal@xxxxxxxxx> wrote:
> ---------- Videresendt melding ----------
> Fra:
> Dato: 15. nov. 2012 07:35
> Emne: Re: [Dolfin] unsigned int -> std::size_t
> Til: "Garth N. Wells" <gnw20@xxxxxxxxx>
>
>
> A typedef for the chosen linear algebra backend? How is that possible with
> dynamic choice of backend?
>

A 'primary' backend will need to be decided at configure time, and the
index type will match the index type of the primary backend. I don't
see any way to get around this. Templating some functions will not
help because the dof map needs to use a compatible index type, and
this would tie a dof map to a backend (and templates will make the
code more complicated).

At present we just assume that all backends use an index type that is
compatible with unsigned int, but we can't justify this assumption.
Flaws in DOLFIN la handling have shown up with the release of Trilinos
11, which introduces 64-bit ints to its interface. PETSc uses
PetscInt, and we have just assumed that it's compatible with unsigned
int.

Garth


> Martin
>
> Den 14. nov. 2012 18:06 skrev "Garth N. Wells" <gnw20@xxxxxxxxx> følgende:
>
> _______________________________________________
> Mailing list: https://launchpad.net/~dolfin
> Post to     : dolfin@xxxxxxxxxxxxxxxxxxx
> Unsubscribe : https://launchpad.net/~dolfin
> More help   : https://help.launchpad.net/ListHelp
>