ufl team mailing list archive

[Johan Hake <hake@xxxxxxxxx>]

On Wednesday 01 April 2009 01:19:14 Anders Logg wrote:
> On Tue, Mar 31, 2009 at 11:38:08PM +0200, Johan Hake wrote:
> > On Tuesday 31 March 2009 23:06:15 Anders Logg wrote:
> > > On Tue, Mar 31, 2009 at 10:09:26PM +0200, Johan Hake wrote:
> > > > On Tuesday 31 March 2009 21:24:21 Martin Sandve Alnæs wrote:
> > > > > 2009/3/31 Anders Logg <logg@xxxxxxxxx>:
> > > > > > On Tue, Mar 31, 2009 at 08:39:42PM +0200, Johan Hake wrote:
> > > > > >> On Tuesday 31 March 2009 17:13:13 Martin Sandve Alnæs wrote:
> > > > > >> > On Tue, Mar 31, 2009 at 3:55 PM, Anders Logg <logg@xxxxxxxxx>
> >
> > wrote:
> > > > > >> > > On Tue, Mar 31, 2009 at 01:06:36PM +0200, Martin Sandve
> > > > > >> > > Alnæs
> >
> > wrote:
> > > > > >> > >> On Mon, Mar 30, 2009 at 7:48 PM,  <logg@xxxxxxxxx> wrote:
> > > > > >> > >> >> I'm ok with the "forms / (a,L,M)" feature, and that
> > > > > >> > >> >> pretty much solves the interpretation problem for (u,v)
> > > > > >> > >> >> in that context. We should also have an optional list
> > > > > >> > >> >> "elements" like "forms". I like
> > > > > >> > >> >>   forms = [a, L]
> > > > > >> > >> >> better, quotes are unnecessary.
> > > > > >> > >> >
> > > > > >> > >> > ok!
> > > > > >> > >> >
> > > > > >> > >> >> In the context of PyDOLFIN, PyDOLFIN can itself check
> > > > > >> > >> >> for tuple or Form, so we don't need to check it
> > > > > >> > >> >> everywhere.
> > > > > >> > >> >
> > > > > >> > >> > I don't think DOLFIN should need to check for this.
> > > > > >> > >> > Wouldn't it be better to let the form compiler handle it?
> > > > > >> > >> >
> > > > > >> > >> > Which interfaces does SFC have? FFC has two interfaces:
> > > > > >> > >> >
> > > > > >> > >> > 1. The compile() command in FFC (takes a single object or
> > > > > >> > >> > list of objects)
> > > > > >> > >>
> > > > > >> > >> compile is a builtin function in Python, so this should be
> > > > > >> > >> renamed.
> > > > > >> > >
> > > > > >> > > Good point. I've been told this before (by Rob). Do you have
> > > > > >> > > a good suggestion for a better name?
> > > > > >> >
> > > > > >> > I have
> > > > > >> > def generate_code(input, options=None):
> > > > > >> > def jit(input, options=None):
> > > > > >>
> > > > > >> Will this be different if we let ufc take care of the jit
> > > > > >> compilation?
> > > > > >>
> > > > > >> I think,
> > > > > >>
> > > > > >>   def generate_code(input, options=None):
> > > > > >
> > > > > > I think it should be made more explicit:
> > > > > >
> > > > > >  def compile_form(form, options=None)
> > > > > >  def compile_forms(forms, options=None)
> > > > > >  def compile_element(element, options=None)
> > > > > >  def compile_elements(elements, options=None)
> > > > >
> > > > > Why? It's convenient to share code between these.
> > > >
> > > > Agree.
> > >
> > > Yes, but that's an implementation issue. It's perfeclty fine to
> > > implement compile form by
> > >
> > >   return compile_forms([form], options)
> > >
> > > or even
> > >
> > >   return _compile_objects([form], options)
> > >
> > > Having separate functions simplifies error checking on input.
> >
> > You meen that ufc provides a jit function. This function check what is
> > provided and call the proper function, you mentioned above, which is
> > provided by the formcompiler?
> >
> > Couldn't we just send the ufl input to generate_code(). Then we compile
> > the extension module and based on the ufl input we try to instantiate the
> > form(s) or finite element(s) and dofmap(s) and return these to the user.
> > Based on the input we type check the instantiated objects and that is
> > enough?
>
> Does the jit function need to know what type of objects it gets? If it
> knows whether an object is a form or element, then it appropriate to
> call either compile_form or compile_element. If not, then I agree it's
> better to let the form compiler resolve the type of object.

I vote for this. The interface between ufc.jit and the formcompiler will then 
be minimal, and that is good.

I added the type check suggestion as a sanity check for what the formcompiler 
returns. But I do not think it is nescessary.

> > > > > >>   def signature(input, options=None):
> > > > > >>
> > > > > >> make sense then.
> > > > > >
> > > > > > This looks like a function that just computes a signature.
> > > > >
> > > > > Because that's what it is? SFC has a similar function. I suggest
> > > > > compute_signature.
> > > >
> > > > Sounds good.
> > >
> > > Aren't we talking about the call to the JIT compiler? What is
> > > signature supposed to do?
> >
> > The jit function will be implemented in ufc. ufc needs to be able to
> > compute a signature to check whether the form(s) or element(s) allready
> > are compiled. This, as I have argued above but still not sure is right,
> > is formcompiler specific.
>
> ok, then I understand. Should it be named something like compute_signature?

I think that sounds good.

Johan