dolfin team mailing list archive

[Anders Logg <logg@xxxxxxxxx>]

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 / ???

--
Anders