Ok, great :) Is there a better place to report documentation errors than as bugs?

Martin

Den 13. nov. 2012 kl. 19:22 skrev Anders Logg <email address hidden>:

> I agree it may be confusing and I can clarify this in the
> documentation. But I would not call this a bug. It is a well-known
> feature that DirichletBC can be used to set "boundary conditions"
> anywhere. It's been like that for ca 10 years. That's also why we have
> the on_boundary parameter to allow setting conditions on the actual
> boundary.
> 
> --
> Anders
> 
> 
> On Tue, Nov 13, 2012 at 10:40:04AM -0000, Martin Sandve Alnæs wrote:
>> Boundary (topology), the closure minus the interior of a subset of a
>> topological space; an edge in the topology of manifolds, as in the case
>> of a 'manifold with boundary'
>> 
>> As I said above, this is at the very least a documentation bug. The
>> sentence I quote makes no sense when all facets may be considered on the
>> boundary. I.e. "a facet that is entirely on the boundary". An
>> alternative interpretation of what "boundary" means also does not match
>> the on_boundary argument to subdomain.inside. And BoundaryMesh takes the
>> exterior boundary. Right? So some clarification of terms is in order, at
>> least in the DirichletBC documentation.
>> 
>> Martin
>> 
>> Den 13. nov. 2012 kl. 10:12 skrev Anders Logg <email address hidden>:
>> 
>>> This is not a bug. The problem is the interpretation of what boundary
>>> means. The boundary is whatever the user specifies and it can lie in
>>> the interior.
>>> 
>>>> Public bug reported:
>>>> 
>>>> According to
>>>> 
>>>> http://fenicsproject.org/documentation/dolfin/1.0.0/python/programmers-
>>>> reference/fem/bcs/DirichletBC.html#dolfin.fem.bcs.DirichletBC
>>>> 
>>>> "The topological approach is faster, but will only identify degrees of
>>>> freedom that are located on a facet that is entirely on the boundary."
>>>> 
>>>> However, this does not seem to be the case. I will attach here a code
>>>> which changes behaviour when switching between marking all facets or all
>>>> facets on the boundary, look for the lines:
>>>> 
>>>> if enable_bug:
>>>>   boundaries.set_all(walldomain)
>>>> else:
>>>>   Wall().mark(boundaries, walldomain)
>>>> 
>>>> ** Affects: dolfin
>>>>    Importance: Undecided
>>>>        Status: New
>>>> 
>>> 
>> 
> 
> -- 
> You received this bug notification because you are a member of DOLFIN
> Core Team, which is subscribed to DOLFIN.
> https://bugs.launchpad.net/bugs/1077912
> 
> Title:
>  Incorrect DirichletBC behaviour applying to interior facets
> 
> Status in DOLFIN:
>  New
> 
> Bug description:
>  According to
> 
>  http://fenicsproject.org/documentation/dolfin/1.0.0/python
>  /programmers-
>  reference/fem/bcs/DirichletBC.html#dolfin.fem.bcs.DirichletBC
> 
>  "The topological approach is faster, but will only identify degrees of
>  freedom that are located on a facet that is entirely on the boundary."
> 
>  However, this does not seem to be the case. I will attach here a code
>  which changes behaviour when switching between marking all facets or
>  all facets on the boundary, look for the lines:
> 
>  if enable_bug:
>      boundaries.set_all(walldomain)
>  else:
>      Wall().mark(boundaries, walldomain)
> 
> To manage notifications about this bug go to:
> https://bugs.launchpad.net/dolfin/+bug/1077912/+subscriptions