Comment 6 for bug 1010850

On Mon, Jun 11, 2012 at 02:42:51PM +0200, Anders Logg wrote:
> On Sun, Jun 10, 2012 at 01:21:57PM -0000, Marie Rognes wrote:
> > Response to 4/
> >
> > (Caveat: I've never used PointSource)
> >
> > How about adding a new measure: a point measure, corresponding to evaluation at a given point,
> > say
> >
> > dp
> >
> > Could that resolve the issues at hand?
>
> I think that would be neat.
>
> We set (formally)
>
> dp(\bar{x}) = \delta_{\bar{x}} dx
>
> and then the generated code would need to
>
> 1. Check whether point is in the current triangle (easily handled with
> an appropriate code-snippet)
>
> 2. Evaluate the integrand at the point in question and add to the
> local tensor
>
> This would require adding an addition integral to UFC:
>
> cell_integral
> exterior_facet_integral
> interior_facet_integral
> dirac_integral / point_integral / ???

Saved as blueprint:

https://blueprints.launchpad.net/dolfin/+spec/dirac-measure-point-source

--
Anders