dolfin team mailing list archive

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

Anders Logg wrote:
> On Tue, Sep 29, 2009 at 12:42:54PM +0100, Garth N. Wells wrote:
> > Anders Logg wrote:
> > > On Tue, Sep 29, 2009 at 07:39:01AM +0100, Garth N. Wells wrote:
> > > > Is there a reason why the MeshFunction.get(..) functions return by value
> > > > rather then reference, e.g. it is currently
> > > >
> > > >      inline T get(const MeshEntity& entity) const
> > > >
> > > > rather than
> > > >
> > > >      inline T& get(const MeshEntity& entity) const
> > > >
> > > > Garth
> > > Yes, we have a set() function for setting the values.
> > I know, but I would like to get a reference rather than copying data
> >
> >     unsigned int index = 3;
> >     const std::vector<double>& vec =  mesh_function.get(index)
> >
> > I can do this when I have the MeshEntitiy, but not when using the index.
>
> Does it work if you do
>
>   &vec[0] = mesh_function.values();

Probably, bit it's not what I want. I have a std::vector attached to 
mesh entities (MeshFunction<std::vector<double> >). I want a reference 
to the std::vector attached to a particular entity

  std::vector<double> vec& =  mesh_function(my_entity);

is fine, but

  std::vector<double> vec& =  mesh_function.get(my_index);

is not.

Back to my question: Is there a reason why MeshFunction::get returns by 
value and not by reference?

Garth


> ?
>
>
> --
> Anders
>
>
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