ufl team mailing list archive

[Martin Sandve Alnæs <martinal@xxxxxxxxx>]

On Tue, Mar 3, 2009 at 6:29 PM, Kristian Oelgaard
<k.b.oelgaard@xxxxxxxxxx> wrote:
> Quoting Martin Sandve Alnæs <martinal@xxxxxxxxx>:
>
>> On Tue, Mar 3, 2009 at 4:37 PM, Kristian Oelgaard
>> <k.b.oelgaard@xxxxxxxxxx> wrote:
>> > Quoting Martin Sandve Alnæs <martinal@xxxxxxxxx>:
>> >
>> >> Nothing implemented, no.
>> >> I'll have to think about it.
>> >>
>> >> Martin
>> >
>> > Could someone please fill me in on the most important details of
>> ListTensor?
>> > Looking at the sub tree I get a strong urge to just ignoring it, would that
>> be safe?
>> >
>> > Kristian
>>
>> I don't get what you're asking for here. Temporarily you can
>> probably ignore it, but in the end it should be supported.
>
> I had a second look at Indexed vs. ComponentTensor (and ListTensor) and I think
> I managed to make some sense out of it. But why does ListTensor not have indices
> like ComponentTensor?
>
> Kristian

Why should it have indices? It represents a tensor composed of an
explicit list of arbitrary subtensors with no connection whatsoever.
(If its subtensors are scalar expressions, think of it as ListVector,
which it was in the first version)

Example:
  w = as_vector((1.0, 2.0)) # -> ListTensor((FloatValue(1.0), FloatValue(2.0))
  fixed_convection = dot(w, grad(u))

Martin